Congenital diaphragmatic hernia: clinical guidelines

List of Abbreviations

CDH – congenital diaphragmatic hernia

HFOV – high-frequency oscillatory ventilation

HH – hiatal hernia

GER – gastroesophageal reflux

GERD – gastroesophageal reflux disease

GI – gastrointestinal tract

IMV – invasive mechanical ventilation

ABDS – acid-base balance status

MSCT – multislice computed tomography

NIBP – non-invasive blood pressure

NSG – neurosonography

ICU – intensive care unit

ADH – anterior diaphragmatic hernia

PCR – polymerase chain reaction

SBP – systolic blood pressure

MAP – mean arterial pressure

CDU – color duplex ultrasonography

US – ultrasound examination

CNS – central nervous system

HR – heart rate

EGD – esophagogastroduodenoscopy

ETT – endotracheal tube

EchoCG – echocardiography

ECG – electrocardiography

C – lung compliance

CDP (Paw) – continuous distending pressure

ETCO₂ – end-tidal carbon dioxide

Fr – ventilation frequency

FiO₂ – fraction of inspired oxygen

IO – oxygenation index

Hz – frequency in HFOV

MAP – mean airway pressure

PIP – peak inspiratory pressure

PEEP – positive end-expiratory pressure

PaCO₂ – partial pressure of carbon dioxide in arterial blood

PaO₂ – partial pressure of oxygen in arterial blood

ΔP – oscillatory pressure amplitude

R – chest wall resistance

SpO₂ – oxygen saturation of hemoglobin in mixed venous blood

Tin – inspiratory time

Vt – tidal volume

Terms and Definitions

Diaphragmatic hernias refer to the displacement of abdominal organs into the thoracic cavity through a defect in the diaphragm.

Congenital diaphragmatic hernia of the diaphragmatic dome is a pleuroperitoneal hernia, the cause of which may be the absence of diaphragmatic muscle attachment in the costovertebral region (Bochdalek hernia on the left; Morgagni hernia on the right); most commonly, the defect is localized on the left, and such a hernia is called false. Another cause of congenital diaphragmatic hernia is muscular hypoplasia in certain areas of the pleuroperitoneal membrane, leading to the formation of hernias with a sac whose walls consist of serous membranes – the peritoneal and pleural layers. Such hernias are called true.

Hiatal hernia is the displacement of abdominal contents through the esophageal hiatus of the diaphragm due to its widening.

Anterior diaphragmatic hernias are a condition characterized by a defect in the sternocostal part of the diaphragm through which herniation of abdominal organs into the thoracic cavity occurs.

1. Brief information on the disease or condition

1.1 Definition of the disease or condition

Congenital diaphragmatic hernia (CDH) is a developmental anomaly of the diaphragm resulting from impaired obliteration of the pleuroperitoneal canal or diaphragmatic insufficiency, which leads to impaired separation of the abdominal and thoracic cavities and displacement of the stomach, spleen, intestines and/or liver, and kidney into the thoracic cavity [1–3].

Hiatal hernia is a condition associated with the displacement of the abdominal esophagus, cardia, upper stomach, and sometimes intestinal loops through the esophageal hiatus into the thoracic cavity. Hiatal hernias are true hernias and are divided into two large groups: sliding (axial) and paraesophageal. Sliding hernias are the most common (approximately 80-90% of cases). In sliding hernias, the gastroesophageal junction along with the stomach is displaced through the esophageal hiatus above the level of the diaphragm. The esophagus is usually of normal length, but due to upward displacement, it may be deformed and tortuous. Paraesophageal hernias are characterized by the displacement of a portion of the stomach and/or other abdominal organs (greater omentum and intestines) upward alongside the esophagus. In this case, the gastroesophageal junction remains in its normal anatomical position. Hiatal hernias are not always fixed. The degree of upward displacement and the shape of the stomach may vary depending on the patient's position, the degree of filling, and the composition of the gastric contents (solid or liquid food, gas). The displacement of the stomach in hiatal hernias can be partial or complete.

Diaphragmatic eventration is a persistent high elevation of the diaphragm while it maintains its continuity and normal attachments. The underlying cause of this condition is impaired innervation of the diaphragm due to injury or involvement of the phrenic nerve in a pathological process, followed by neurogenic dystrophy of the diaphragmatic muscle elements. The weakened diaphragmatic dome is elevated and displaced into the thoracic cavity, which can lead to respiratory impairment. During eventration, the diaphragm retains its anatomical integrity, but may appear thin and membranous. This is precisely what distinguishes it from a congenital diaphragmatic hernia. Diaphragmatic eventration results in the abnormal elevation of a single diaphragmatic dome as a result of varying degrees of paralysis, aplasia, or atrophy of muscle fibers. Unlike true diaphragmatic eventration, diaphragmatic paresis or paralysis is a more common acquired condition that usually occurs as a result of phrenic nerve injury associated with a tumor or trauma.

1.2 Etiology and pathogenesis of the disease or condition (group of diseases or conditions)

Congenital diaphragmatic hernia

The exact causes and mechanisms of CDH development have not been fully established. The anomaly begins to form in the embryo at 4 weeks of gestation, when the septum primum between the pericardial cavity and the embryonic trunk is formed. At 8–10 weeks of gestation, a diaphragmatic defect occurs as a result of impaired closure of the pleuroperitoneal canal, most commonly in the posterolateral region (Bochdalek hernia). Abdominal organs may herniate through the defect into the pleural cavity throughout the period following the return of the intestines into the abdominal cavity (9–10 weeks of gestation). Muscular hypoplasia in certain areas of the pleuroperitoneal membrane leads to the formation of hernias with a sac whose walls consist of serous membranes – the peritoneal and pleural layers. The sac protrudes into the thoracic cavity, and its lumen contains the displaced abdominal organs (intestines, stomach, spleen) [1–3].

Significant pulmonary hypoplasia is observed on the side of the hernia; however, the contralateral lung typically also has an abnormal structure and reduced mass compared to normal. Pulmonary hypoplasia is characterized by a reduction in the number of bronchioles and alveoli, and surfactant system dysfunction. A reduction in the number of arterioles and their diameter, along with thickening of the muscular layer, leads to the development of pulmonary hypertension. The displacement of a significant number of abdominal organs into the thoracic cavity leads to decreased left ventricular contractility, left ventricular hypoplasia, and increased pulmonary artery pressure [4,5].

No single gene mutation has been identified as a factor leading to CDH formation. It is believed that CDH may be associated with chromosomal abnormalities and syndromes: trisomy 18, Turner syndrome (45,XO), Fryns syndrome, deletion of the short arm of chromosome 27, Goldenhar syndrome [1,2,4].

Hiatal hernia

The development of a sliding hiatal hernia is promoted by structural alterations in the components forming the esophageal hiatus, elevated intra-abdominal pressure, and obesity. When the configuration of the crura of the diaphragm forming the esophageal hiatus changes, weak areas develop within it, predominantly along the posterior semicircle. Tissues or organs protruding into them encounter insufficient resistance, resulting in the progressive widening of the esophageal hiatus and its muscular and connective tissue structures. Fixation structures (phrenoesophageal membrane, hepatogastric and gastrophrenic ligaments) may be congenitally weakened or undergo age-related involutional changes, making them prone to stretching and tearing. Such changes in connective tissue structures occur as a result of malnutrition and severe diseases.

A certain role in the formation of a hiatal hernia is played by increased intra-abdominal pressure, observed in obesity, ascites, prolonged coughing, chronic lung diseases, vomiting, and heavy lifting. In addition to increasing intra-abdominal pressure, obesity promotes fat deposition in the retroperitoneal space behind the esophagogastric junction, which leads to the dilation of this area. Great importance is also attached to the weakening and stretching of the phrenoesophageal membrane, which in a healthy person prevents the cardia from shifting upward. When intra-abdominal pressure increases, the size of the esophageal hiatus increases, through which the cardia shifts into the thoracic cavity, the abdominal part of the esophagus shortens, and the angle of His straightens. The displacement of the cardia is facilitated by negative pressure in the thoracic cavity, the phrenoesophageal ligament stretches, lateral traction on the esophageal wall increases, and the function of the lower esophageal sphincter changes. As a result, the closing function of the cardia is drastically impaired, creating favorable conditions for the reflux of gastric contents into the esophagus and the development of reflux esophagitis. At the same time, spastic contractions of the esophagus resulting from peptic esophagitis or its cicatricial shortening contribute to increased fixation of the hiatal hernia. Thus, a hiatal hernia and reflux esophagitis mutually aggravate each other.

Paraesophageal hernia is a rarer pathology than sliding hernia. According to several authors, it accounts for 15% of all hiatal hernia cases. In this case, the esophagogastric junction is located below the diaphragm, and the phrenoesophageal ligament is well-defined and not stretched. The gastric fundus and greater curvature of the stomach shift into the thoracic cavity through the widened esophageal hiatus. The contents of the paraesophageal hernia are covered by the peritoneum on all sides, i.e., a hernia sac is present. Sometimes the hernial protrusion is not located next to the esophagus, but is separated from it by fibrous-muscular fibers. With an increase in the size of the hernia, the cardia may shift into the mediastinum. In such cases, it is referred to as a combined hernia. In addition to the stomach, the contents of the hernia sac can include the small and large intestine, greater omentum, and spleen.

Anterior diaphragmatic hernia

Diaphragmatic hernias that form near the sternum in the area of the sternal muscular part of the diaphragm (retrosternal) or Larrey's triangle (costosternal) are conventionally called "parasternal" hernias, or Morgagni hernias. In adults, diaphragmatic hernias account for 2-3% of all diaphragmatic hernias, and they occur much more frequently on the right side than on the left. Morgagni hernias have a hernia sac located in the anterior mediastinum, and the hernia contents are usually the transverse colon, greater omentum, and less frequently the stomach.

Anatomically, a retrosternal hernia represents a developmental defect of the diaphragm with the formation of a "weak spot" in the area of the sternocostal triangle, which lacks muscle fibers [6]. This type of hernia is often referred to as a Morgagni hernia in honor of the Italian anatomist Giovanni Battista Morgagni, who first described this pathology, and also as a Larrey hernia in honor of the French surgeon Dominique Jean Larrey, who described the access to the pericardium through the left sternocostal cleft [7,8].

In the literature, anterior diaphragmatic hernias have various names: Morgagni hernia, Larrey hernia, Morgagni-Larrey hernia, retrocostoxiphoid, parasternal, retrochondrosternal, retrosternal, subcostal, substernal, and subcostosternal hernia [9–11]. There is also confusion in the descriptions of Morgagni and Larrey hernias. Dapri et al. describe a Morgagni hernia on the left side [12], while other authors describe a Morgagni hernia on the right and a Larrey hernia on the left side [13]. Some accept both the right and left sides for Morgagni or Larrey hernias [14,15].

The hernial protrusion from the abdominal cavity into the anterior mediastinum occurs through a diaphragmatic defect behind the sternum (Larrey's cleft) with the formation of a Morgagni hernia [16]. The hernia sac is formed by the parietal peritoneum. Some authors call a left-sided hernia a Larrey hernia, and a right-sided one a Morgagni hernia. Their contents usually include a part of the liver, the small and large intestine, and less commonly the spleen.

Frenopericardial hernias are false hernias; the defect is located in the tendinous part of the diaphragm and the adjacent part of the pericardium. Through this defect, abdominal organs can directly shift into the pericardial cavity, and, conversely, the heart is partially dislocated through the defect in the diaphragm into the abdominal cavity (retrograde hernia). A retrosternal defect in the pericardium and diaphragm may be combined with epigastric diastasis or an epigastric umbilical cord hernia (Cantrell's pentad).

Diaphragmatic relaxation (eventration)

Diaphragmatic relaxation can be congenital or acquired. Congenital relaxation arises as a result of impaired development of the diaphragmatic muscles or the absence of the phrenic nerves. According to some sources, during embryogenesis, abnormal or delayed migration of myoblasts from the upper cervical somites into the septum transversum and pleuroperitoneal membrane occurs, leading to a structural deficit of the diaphragmatic muscle. Macroscopically, the affected part of the diaphragm becomes thinned, membranous, and lacks a muscle layer. Microscopic examination reveals a scarcity or complete absence of muscle fibers, as well as diffuse fibroelastic changes.

Acquired relaxation arises due to several causes: damage to the phrenic nerve as a result of birth trauma or thoracic surgery associated with congenital heart disease, transection of the phrenic nerve by a neoplasm or surgical resection; the loss of contractile ability leads to muscle atrophy with high standing of the diaphragmatic dome.

1.3 Epidemiology of the Disease or Condition

Congenital diaphragmatic hernia

1 in 2000-4000 newborns.

Sex ratio 1:1 [1,2,17].

Hiatal hernia

Hiatal hernia is a relatively common condition: it occurs in 5% of the entire adult population, and in 50% of patients it causes no clinical manifestations and is therefore undiagnosed. According to some authors, the incidence is 2-16% in individuals suffering from gastrointestinal disorders, and 5-15% in patients undergoing radiological examination for digestive tract diseases.

The true incidence of this condition is difficult to determine because in most cases hiatal hernias are clinically silent. At the same time, it is believed that in individuals younger than 30 years, such anatomical changes are noted in 10-15% of cases, while in individuals older than 50 years – in 60% [18–21]. Pediatric statistics differ somewhat from these data. Congenital diaphragmatic hernias occur in one of 1,700 newborns. According to N. G. Zernov et al. (1988), hiatal hernias are detected in 5.3% of children with reflux esophagitis [22,23]. According to literature from the last decade, the frequency of sliding hiatal hernias in children with esophageal diseases ranges from 4.5-7.2%. At the same time, gender differences are insignificant [24].

Anterior diaphragmatic hernia

Anterior diaphragmatic hernia (ADH) is a rare congenital pathology occurring in children with an incidence of 1:4800 and accounting for 1-6% of all congenital diaphragmatic hernias [25–29].

In the majority of patients, anterior diaphragmatic hernias are diagnosed and treated in childhood. However, in 5% of cases, they can also manifest in adults [30]. As a rule, Morgagni-Larrey hernias in adults develop due to increased intra-abdominal pressure and are associated with various acquired conditions (pregnancy, obesity, constipation, trauma, etc.) [31,32].

Diaphragmatic relaxation (eventration)

According to the literature, diaphragmatic relaxation is a rare pathology that occurs in 0.05/1000 newborns, affecting predominantly boys in 60-80% of cases, most frequently affecting the left dome of the diaphragm. It accounts for 5-7% of all diaphragmatic diseases.

1.4 Features of Coding the Disease or Condition

K44.0 Diaphragmatic hernia with obstruction, without gangrene

Diaphragmatic hernia: causing obstruction; incarcerated; irreducible; without gangrene; strangulated.

K44.1 Diaphragmatic hernia with gangrene

Gangrenous diaphragmatic hernia.

K44.9 Diaphragmatic hernia without obstruction or gangrene

Q40.1 Congenital hiatal hernia

Q79.0 Congenital diaphragmatic hernia

Q79.1 Other congenital malformations of diaphragm

Agenesis of diaphragm

Congenital malformation of diaphragm, NOS

Eventration of diaphragm

1.5 Classification of the disease or condition

1. Anatomical classification of congenital diaphragmatic hernias in children:

a) Posterior diaphragmatic hernias

- false (Bochdalek hernia)

b) Diaphragmatic dome hernias

- true (partial, subtotal, total)

- false (partial, subtotal, total)

c) Anterior diaphragmatic hernias

- false (frenopericardial)

- true (retrosternal)

2. By side of lesion:

Left-sided

Right-sided

Bilateral

3. By hernia shape:

• False, posterolateral (in the absence of a hernia sac), Bochdalek hernia (in left-sided localization), Morgagni hernia (in right-sided localization)

• True, diaphragmatic eventration, diaphragmatic evisceration (with the presence of a hernia sac)

4. Intraoperative classification:

• type A – defect in the muscular part of the diaphragm, occupies no more than 10% of the dome circumference, lateral edges of the defect come together

• type B – defect in the muscular part, occupies no more than 50% of the dome circumference, lateral edges of the defect do not come together and are located at a distance from each other

• type C – part of the diaphragmatic dome is present, the defect occupies more than 50% of the diaphragm circumference, lateral edges of the defect are located at a considerable distance from each other

• type D – interpreted as agenesis of the diaphragmatic dome, up to 90% of the dome tissue is absent

Hiatal hernia

Attempts to classify hiatal hernias into subtypes began at the beginning of the last century [33]. The most commonly used classification in Russia is the anatomical and radiologic classification of hiatal hernias [34,35]. B.V. Petrovsky et al. proposed the following classification of hiatal hernias:

I. Sliding (axial) hiatal hernias:

1. Esophageal hiatal hernia;

2. Cardia hiatal hernia;

3. Cardiofundal hiatal hernia.

II. Paraesophageal hiatal hernias:

1. Fundal hiatal hernia;

2. Antral hiatal hernia;

3. Intestinal hiatal hernia (small and large bowel);

4. Combined intestinogastric hiatal hernia;

5. Omental hiatal hernia.

III. Giant hiatal hernias:

1. Subtotal gastric hiatal hernia;

2. Total gastric hiatal hernia.

IV. Grade 1 and 2 short esophagus:

1. Acquired short esophagus;

2. Congenital short esophagus.

The modern anatomical classification adopted by consensus statements in most European countries and the USA distinguishes types I-IV hiatal hernias [36]:

Type I – sliding hiatal hernias, where the gastroesophageal junction is displaced above the diaphragm, the stomach remains in its usual longitudinal position, and the fundus remains below the gastroesophageal junction.

Type II – these are classic paraesophageal hernias; the gastroesophageal junction remains in its normal anatomical position, but part of the fundus adjacent to the esophagus herniates through the diaphragmatic hiatus.

Type III – represents a combination of types I and II, with both the gastroesophageal junction and the fundus herniating through the esophageal hiatus of the diaphragm. The fundus lies above the gastroesophageal junction.

Type IV – characterized by the presence of another structure in the hernial sac other than the stomach, such as the omentum, large or small intestine, or spleen.

Anterior diaphragmatic hernia [16]

I. Retrosternal hernias (true):

1. Retrocostoxiphoid (substernal);

2. Parasternal (costosternal)

II. Frenopericardial hernias (false)

Diaphragmatic eventration can be divided into the following types:

1. Unilateral or bilateral

2. Partial (anterior, posterolateral, medial) or complete.

Complete eventration of the diaphragm invariably occurs on the left side, whereas partial eventration of the diaphragm is almost always observed on the right side.

1. Congenital or acquired.

In congenital eventration, the diaphragm consists of a thin membrane attached peripherally to healthy muscle. In acquired eventration, the tendinous center is in a normal state, and the diaphragm consists of normally developed muscle that is atrophic.

According to the clinical course of diaphragmatic eventration, B.V. Petrovsky et al. distinguish 4 forms [37]:

1. Asymptomatic;

2. With mild clinical manifestations;

3. With pronounced clinical symptoms;

4. Complicated (gastric volvulus, gastric ulcer, bleeding, etc.).

1.6 Clinical presentation of the disease or condition

Congenital diaphragmatic hernia

The clinical presentation of congenital diaphragmatic hernia is manifested by respiratory distress syndrome. Clinical scenarios after birth range from immediate severe respiratory distress with concomitant respiratory acidosis and hemodynamic instability to a stable period with delayed distress. Acute respiratory failure progresses rapidly. On examination, besides cyanosis, attention is drawn to chest asymmetry with bulging on the affected side and absence of excursion of this affected half. A characteristic symptom is a scaphoid, sunken abdomen. Heart sounds (in left-sided hernia) are auscultated to the right of the sternum, and in right-sided hernia along the left anterior axillary line, indicating displacement of the heart to the healthy side.

In true diaphragmatic hernias, with bulging of a limited part of the diaphragm on the right, when the contents consist of an herniated portion of the liver, clinical symptoms are absent. With such hernias localized on the left, despite the absence of visible clinical manifestations, there is some displacement of the heart with its rotation, which can cause latent cardiovascular disorders. To detect them, additional diagnostic methods should be performed [1–3,38].

Hiatal hernias

The clinical presentation of an esophageal hernia is mainly due to gastroesophageal reflux (GER) resulting from impaired function of the cardiac part of the esophagus. In cases where the child retains normal lower esophageal sphincter function, the disease may be asymptomatic.

Symptoms of the disease in most cases appear early, in almost half of the cases during infancy. As with gastroesophageal reflux disease (GERD) without an esophageal hernia, three main clinical syndromes can be distinguished in children: vomiting, esophagitis, and respiratory complications, which often occur in the same patient [39–45]. It should be noted that in esophageal hernias, the clinical signs of the disease are more pronounced and respond poorly to conservative and medical treatment. Therefore, the presence of GER symptoms in children with esophageal hernias is usually an indication for corrective and antireflux surgery. Restlessness and vomiting are the leading symptoms of the disease in young children. Vomiting is most often associated with feeding, has a very varied character, and can be profuse or in the form of regurgitation. Gastric contents, sometimes mixed with bile, are most often found in the vomitus. Due to constant and persistent vomiting, children gain weight poorly. During certain periods, especially in the first months of life, they even lose weight and become wasted. Older children are often physically less developed. Signs of esophagitis (abdominal pain and heartburn) are mainly complained about by older children. Pain typically occurs after eating, in the supine position, or when bending the torso, which is associated with the reflux of gastric contents into the esophagus and its aggressive effect on the mucosa. Erosive and ulcerative esophagitis can cause occult gastrointestinal bleeding in approximately 50% of children. As a result, chronic iron-deficiency anemia develops, the causes of which are sometimes difficult to establish. Massive esophageal bleeding in the form of hematemesis or melena is not characteristic of esophageal hernias. A severe complication of esophagitis is peptic esophageal strictures, usually resulting from ulcer scarring. These strictures are most often short and located in the lower esophagus. Frequently, in approximately 30–40% of cases, especially in infants, recurrent aspiration pneumonia occurs. Other respiratory pathologies are also common, such as tracheobronchitis, nocturnal cough, and bronchial asthma. In approximately 15% of patients, otorhinolaryngological pathology develops, including laryngitis, pharyngitis, otitis media, sinusitis, etc.

Anterior diaphragmatic hernia

The clinical picture of Morgagni hernia is characterized by a slow development. Even with significant sizes, they can remain pauci-symptomatic for a long time and occur under the "mask" of other diseases. Symptoms of gastrointestinal tract dysfunction are more characteristic of retrosternal (parasternal) hernias. Compression of the lung or heart in this pathology is usually insignificant. The child periodically experiences pain and discomfort in the epigastric region, sometimes vomiting. Dyspnea, cough, and cyanosis are rare. In almost 50% of cases, this anomaly may be clinically silent. On examination, bulging of the anteroinferior chest wall is noted. By percussion and auscultation, tympanitic note, muffled heart sounds, and absence of absolute cardiac dullness can be determined. If the hernial sac is filled with omentum or a partially detached portion of the liver, along with muffled heart sounds, there will be shortening of the percussion note. Associated anomalies, especially congenital heart defects and trisomy 21, are frequently found in retrosternal hernias.

In phrenicopericardial hernias, the leading symptoms are cyanosis, dyspnea, anxiety, and less commonly vomiting, resulting from the displacement of intestinal loops into the pericardial cavity. Symptoms of the disease often appear in the first weeks and months of life. Strangulation of intestinal loops herniated into the pericardial cavity is possible. Inspection reveals chest bulging. Abdominal asymmetry with retraction in the left hypochondrium is possible. Percussion reveals the disappearance of absolute cardiac dullness. Heart sounds are muffled. In retrograde phrenicopericardial hernias, when prolapse of the heart through the defect is observed, cardiovascular disorders come to the fore. This type of diaphragmatic hernia is most frequently accompanied by multiple malformations (congenital heart defects, transposition of the great vessels, polycystic kidney disease).

Diaphragmatic relaxation (eventration)

Diaphragmatic relaxation is usually asymptomatic and discovered incidentally during routine chest X-ray screening, which is especially characteristic in cases where the relaxation is partial. Symptoms may appear at an older age, which may be associated with weight gain and chest wall compliance; this situation is more typical of total diaphragmatic relaxation.

Total relaxation leads to elevation of the diaphragm with reduced lung volumes and ventilation impairment. This leads to compression of the lung base, causing atelectasis and poor drainage, which can lead to the development of pneumonia. Some children exhibit recurrent respiratory tract infections.

The most severe clinical picture develops with diaphragmatic relaxation in newborns: severe respiratory failure with dyspnea and cyanosis is pronounced, breathing is often arrhythmic, with retraction of the compliant areas of the chest wall, cardiac borders are displaced to the unaffected side, and breath sounds are diminished on the affected side. Most children show symptoms of cardiovascular disorders.

In older children with unilateral lesions, the clinical picture is not pronounced, although dyspnea may occur upon moderate physical exertion.

Despite the fact that respiratory signs are the most common, some patients with diaphragmatic relaxation may develop gastrointestinal abnormalities. These include feeding difficulties, abdominal pain, nausea, vomiting, regurgitation, constipation, and failure to thrive. These are associated with gastric volvulus, which is a known complication of left-sided diaphragmatic eventration. In this condition, the stomach, colon, spleen, and less commonly the small intestine are displaced high up from the abdominal cavity. The displaced stomach undergoes the same positional changes as in a diaphragmatic hernia—its greater curvature turns upward and lies against the diaphragm.

2. Diagnostics, medical indications and contraindications for diagnostic methods

Congenital diaphragmatic hernia

Criteria for establishing the diagnosis/condition:

Diagnosis of congenital diaphragmatic hernia can be made on the basis of:

- prenatal fetal ultrasound data

- physical examination findings

- instrumental examination methods

Differential diagnosis is carried out with:

- lung malformations,

- chest wall masses,

- hydro/chylothorax

- pneumothorax

Principles of diagnosis formulation:

When formulating the diagnosis, the localization, form, and type of diaphragmatic hernia should be indicated. Examples of diagnosis formulations are given below:

1. Left-sided false diaphragmatic hernia type A

2. Right-sided true diaphragmatic hernia type C

2.1 Complaints and Anamnesis

The newborn presents no complaints independently. The medical history is gathered based on prenatal diagnostic data.

In the absence of prenatal data on a congenital anomaly, as well as upon the appearance of signs of respiratory failure at any age, a diaphragmatic hernia must first be ruled out.

2.2 Physical Examination

• Patients with suspected congenital diaphragmatic hernia are recommended to undergo a physical examination in order to establish the diagnosis and determine the severity of the condition in the following scope [1,2,17,46–48]:

- Assessment of skin color;

- Assessment of chest asymmetry;

- Assessment of respiratory function;

- Assessment of cardiac activity;

- Assessment of the abdominal condition

Level CLevel 5Level of recommendation evidence C (reliability level of evidence – 5).

Comment: The general condition of patients with diaphragmatic hernia is usually very severe. Initial signs associated with respiratory distress include tachypnea, chest wall retractions, grunting, cyanosis, and/or pallor. Acute respiratory failure progresses very rapidly. For differential diagnosis with cardiac cyanosis, an oxygen test (breathing 100% oxygen for 5 minutes) must be performed. Upon examination, besides cyanosis, attention is drawn to chest asymmetry with bulging of the affected side and absence of excursion of this hemithorax. A very characteristic symptom is the scaphoid, sunken abdomen. Percussion over the corresponding area of the chest reveals tympanitic note (due to eventration of intestinal loops and stomach into the hemithorax) or dullness (when the liver is located in the right hemithorax). Auscultation reveals absent or sharply diminished breath sounds. Heart sounds (in left-sided hernia) are auscultated to the right of the sternum on the left, and along the left anterior axillary line on the right, indicating a shift of the heart to the healthy side. Sometimes peristalsis of the displaced intestinal loops and a splashing sound can be auscultated through the chest wall. In true diaphragmatic hernias, with bulging of a localized part of the diaphragm on the right, when the content consists of an encroached portion of the liver, clinical symptoms may be absent. In such hernias localized on the left, despite the absence of visible clinical manifestations, there is some displacement of the heart with its rotation, which can cause latent cardiovascular disorders [1,2].

2.3 Laboratory Diagnostics

Specific laboratory diagnostics for diaphragmatic hernia do not exist. Laboratory diagnostic tests should be performed in patients during the diagnosis and treatment of diaphragmatic hernia in the preoperative and postoperative periods. Non-specific diagnostics can be performed by studying blood parameters: a decrease in hydrogen ion concentration (pH), a decrease in buffer substances, and an increase in blood carbon dioxide levels.

2.4 Instrumental Diagnostics

In all cases, instrumental diagnostics is required to diagnose a diaphragmatic hernia.

• Patients with congenital diaphragmatic hernia are recommended to undergo a chest X-ray in order to diagnose the disease and the affected side [1,2].

GDR CLE 5Grade of recommendation C (level of evidence – 5)

Comment: The diagnosis of diaphragmatic hernia is confirmed by chest X-ray: displacement of the stomach/orogastric tube and mediastinal shift toward the contralateral hemithorax. A minimal amount of gas or its absence may be present in the abdominal cavity, especially initially. In left-sided hernia, shadows of varying caliber are visualized in the projection of the left hemithorax. Variability in the position and shapes of areas of radiolucency and opacity is characteristic, which can be seen when comparing two radiographs taken at different times. In right-sided hernia with liver eventration into the right hemithorax, total opacification of the right half of the chest is revealed. The dome of the diaphragm on the affected side is not visualized. Distinguishing a false diaphragmatic hernia from a true one is difficult, especially if the pleural cavity is filled with invaginated abdominal organs. In true left-sided hernias, it is sometimes possible to radiologically trace the upper contour of the hernia sac limiting the intestinal loops that have migrated into the thoracic cavity. When a true hernia is located on the right, its content is usually part of the liver, so radiologically the shadow of the hernia protrusion will have a dense intensity, merging in the lower sections with the main liver shadow, and the upper contour of the hernia will be spherical.

• Patients with congenital diaphragmatic hernia are recommended to undergo electrocardiography, tracing, description, and interpretation of electrocardiographic data in order to assess the condition of the heart muscle, record heart rhythm, and heart rate [17,46].

GDR CLE 5Grade of recommendation C (level of evidence – 5)

Comment: ECG is performed to determine right atrial overload: P-pulmonale in lead II greater than 0.3 mV, right ventricular overload, increase in the R wave in I, V1, V2 greater than 2.1 mV, myocardial changes

• Patients with congenital diaphragmatic hernia are recommended to undergo echocardiography to assess cardiac function and determine the degree of pulmonary hypertension [49,50].

GCR BLEL 3Grade of Recommendation B (Level of Evidence – 3)

Comment: Echocardiography procedure:

1. Assessment of the heart position and the orientation of its apex, taking into account that the heart is always displaced in the opposite direction from the hernia.

2. Anatomical characterization of all heart chambers; for determining the prognosis of the disease, it is important to determine the left ventricular myocardial mass and the ejection fraction of the left and right ventricles.

3. Assessment of the condition of the atrioventricular and semilunar valves. It is important to assess the development of the pulmonary arteries using the Nakata index or the modified index — McGoon index (the ratio of the sum of the diameters of both pulmonary artery branches to the diameter of the descending aorta at the diaphragmatic level), since it has been noted that with an index of less than 1.3, mortality can reach 100%

4. Determination of the localization and size of ventricular and atrial septal defects

5. Determination of the magnitude and direction of blood shunting through fetal communications. In most cases, during the first days after birth, a patent foramen ovale and a patent ductus arteriosus are present with right-to-left or bidirectional blood shunting. Pulmonary hypertension in congenital diaphragmatic hernias is associated with hypertrophy of the pulmonary arteriole wall combined with a decrease in the total cross-sectional area of the pulmonary vessels

6. Analysis of the systolic and diastolic myocardial function of the left and right ventricles (intracardiac pressures, stroke volume and cardiac output, left ventricular fractional shortening, transmitral and transtricuspid diastolic blood flow, pulmonary and systemic blood flow)

7. Precise assessment of the severity of pulmonary hypertension. As a result of increased pressure in the pulmonary circulation, the right heart chambers dilate, and the right ventricle and right atrium acquire a spherical shape. Systolic pulmonary artery pressure is measured from the velocity of the tricuspid regurgitation jet.

8. The diagnosis of pulmonary hypertension is established if the pulmonary artery pressure exceeds 2/3 of the systemic arterial pressure.

Echocardiographic classification of pulmonary hypertension

1. Subsystemic (moderate) – Pulmonary artery pressure is greater than 2/3 of systemic blood pressure

In absolute terms – greater than 50 mm Hg

1. Systemic (severe) – Pulmonary artery pressure equals systemic blood pressure

Bidirectional blood flow through fetal communications is possible

1. Suprasystemic (severe or high) – Pulmonary artery pressure is higher than systemic blood pressure

Right-to-left shunt is possible through fetal communications

2.5 Other Procedures

• In doubtful cases and for differential diagnosis with other chest diseases, it is recommended to perform MSCT (multislice computed tomography of the chest and abdominal cavity) or MRI (magnetic resonance imaging of the chest) [1].

GRC CLEL 4Grade of Recommendation C (Level of Evidence – 4)

Comment: If the patient's condition permits and there are difficulties in differential diagnosis, computed tomography of the chest with intravenous bolus contrast enhancement should be performed. This makes it possible to determine which abdominal organs are located within the thoracic cavity.

Hiatal hernia

Criteria for diagnosis/condition establishment

• anamnestic data indicating the time of symptom onset;

• physical examination findings (see section 1.6);

• instrumental examination data

The diagnostic algorithm for sliding hiatal hernias is identical to that for gastroesophageal reflux disease. Currently, diagnosis of hiatal hernias involves X-ray examination, esophagogastroduodenoscopy (EGD), 24-hour esophageal pH monitoring, manometry, and esophageal scintigraphy. The presence of GER in patients with hiatal hernias can be confirmed using 24-hour pH monitoring, manometry, and esophageal scintigraphy [39,40].

X-ray imaging

• Patients with suspected hiatal hernia are recommended to undergo oral contrast-enhanced X-ray examination to assess the displacement of the stomach above the diaphragm, determine the boundaries of the hernia, and evaluate gastroesophageal reflux [1].

GCR CLEL 5Grade of Recommendation C (Level of Evidence – 5)

Comments: Plain chest radiography can reveal soft tissue opacity with or without a fluid level in the chest. A retrocardiac fluid level on a chest radiograph is a pathognomonic sign of a paraesophageal hiatal hernia. Intraluminal gas may be observed when the hernia contents include bowel loops. In addition, bowel loops may be visualized in an unusual vertical orientation relative to the sac, and a characteristic displacement or upward deformation of the transverse colon may also be observed when the sac contents include the large intestine.

Contrast-enhanced X-ray examination of the upper gastrointestinal tract is the primary diagnostic method for hiatal hernias. Being the most accessible among diagnostic modalities, fluoroscopy during a targeted patient examination using standardized methodological techniques accurately detects hiatal hernia in 95.5% of cases. At the same time, information about the condition of the chest and abdominal organs can be obtained. The radiological sign of a hiatal hernia is the displacement of the stomach, along with its cardia, above the diaphragm. Unlike the esophageal ampulla, which has a smooth-contoured cystoid shape, a hiatal hernia is characterized by irregular contours and typically a larger transverse dimension. Furthermore, a hiatal hernia is detectable in any body position, whereas the esophageal ampulla is formed only in the supine position. Other radiological signs of a hiatal hernia include a tortuous course of the esophagus due to its upward displacement, an obtuse angle of the esophagogastric junction, a high-riding esophagogastric junction, and prominent longitudinal mucosal folds in the supradiaphragmatic portion that appear as a continuation of the gastric folds. Incompetence of the cardia in hiatal hernia is indicated by fluoroscopically detected spontaneous gastroesophageal reflux, as well as positive provocative, loading, or water-siphon tests.

Endoscopic research method

• Patients with suspected hiatal hernia are recommended to undergo esophagogastroduodenoscopy (EGD) to assess inflammatory changes, the presence of a hiatal hernia, and to detect Barrett's esophagus [51–55].

GCR BLEL 3Grade of Recommendation B (Level of Evidence – 3)

Comments: Esophageal hernias are characterized by the displacement of the esophagogastric junction (proximal edge of gastric folds or distal edge of palisade vessels) and the Z-line (squamocolumnar junction) above the diaphragmatic narrowing. There are endoscopic classifications (scales) for hiatal hernias during direct endoscopic examination (Makuuchi classification) [51,52] and retroflexion (Hill grade system) [53]. Attention should also be paid to signs of cardiac incompetence—gaping, widening of the esophageal lumen, and reflux of gastric contents into the esophagus.

EGD plays an important role in diagnosing complications such as GER-esophagitis, peptic esophageal strictures, and Barrett's esophagus. In the majority of patients with a hiatal hernia and GER, peptic esophagitis of varying severity affects the lower third of the esophagus over a length of several centimeters or is confined to the cardiac zone. The mucosa in this area may be brightly hyperemic and easily bleed. In severe cases, an erosive surface covered in places with fibrinous membranes can be observed. Currently, the Los Angeles classification adopted in 1994 is used to describe esophageal erosions [54]. However, mucosal changes due to GER in children with hiatal hernias are often minor or absent. In such cases, the diagnosis of esophagitis can be confirmed by biopsy and histological examination. When endoscopic signs of intestinal metaplasia in the esophagus (Barrett's esophagus) are detected, targeted biopsy is indicated to verify the diagnosis and rule out dysplasia. To detect areas of dysplasia endoscopically, chromoendoscopy with acetic acid solution (up to 3%) and narrow-band imaging are used [55].

Computed tomography

• Patients with suspected complicated hiatal hernia are recommended to undergo computed tomography of the chest and abdomen with intravenous bolus contrast enhancement to identify volvulus and perform preoperative three-dimensional modeling [56].

LeRR CLoE 4Level of recommendation confidence C (level of evidence – 4)

Comments: Computed tomography can be useful in emergency situations for patients with suspected complications in the form of a paraesophageal hernia volvulus. In most cases, parts of the hernia and any organs contained within the hernial sac are clearly visualized in the thoracic cavity.

Multislice CT with sagittal, coronal views, and 3D image modeling has increased the sensitivity of CT in detecting hiatal hernias [56]. In the event of intestinal obstruction and strangulation, dilated bowel segments with fluid levels will be identified in the thoracic and abdominal cavities. Cranial displacement of the gastroesophageal junction or the gastric fundus through the esophageal hiatus can be clearly visualized on contrast-enhanced CT images. In addition, tomography plays a specific role in verifying hiatal hernia recurrence.

Esophageal manometry

• Patients with suspected paraesophageal hiatal hernia are not recommended to undergo esophageal manometry due to anatomical difficulties and unreliable results [57,58].

LeRR CLoE 4Level of recommendation confidence C (level of evidence – 4)

Comments: Esophageal manometry can demonstrate the level of the crura of the diaphragm, the point of respiratory inversion, and the location of the lower esophageal hernia component. In patients with a paraesophageal hernia, positioning the manometric catheter across the lower esophageal sphincter and below the diaphragm can be difficult. Experts suggest that a contrast study demonstrating normal patency may replace the need for manometric examination in patients with paraesophageal hernia [57,58]. However, esophageal motility testing is crucial to ensure correct probe placement during pHmetry — above the lower esophageal sphincter in patients with sliding hernia and symptoms of gastroesophageal reflux. This study aids in the differential diagnosis of systemic diseases of the esophageal musculature.

pHmetry

• Patients with suspected hiatal hernia are not recommended to undergo esophageal and gastric pHmetry due to anatomical difficulties and unreliable results [57,58].

LeRR CLoE 4Level of recommendation confidence C (level of evidence – 4)

Comments: pHmetry is of limited value in the diagnosis of hiatal hernias due to unreliable results associated with anatomical features, but it is essential for detecting reflux disease in patients with type I sliding hernias. To establish indications for surgical intervention in patients with sliding hiatal hernia, it is necessary to confirm pathologic gastroesophageal reflux either by detecting erosive esophagitis or Barrett's esophagus on EGD, or by demonstrating a De Meester score on pHmetry (normal value 14.72).

The basis of patient evaluation for hiatal hernia, especially prior to surgery, is EGD and barium swallow radiography. Contrast studies are more sensitive than endoscopy for detecting sliding hiatal hernia. The significance of various diagnostic methods may depend on clinical manifestations. Incidentally discovered hiatal hernias or those causing minimal symptoms can be evaluated using EGD and radiography. CT may be performed if additional information is needed to guide further decision-making. In situations where the stomach is found in an unusually high position or with an abnormal axis in a patient with acute abdominal pain and vomiting, gastric volvulus must be ruled out.

Anterior diaphragmatic hernia

• Patients with suspected anterior diaphragmatic hernia are recommended to undergo plain targeted chest X-ray in two projections to assess X-ray anatomy [1].

GCR CLEL 5Grade of Recommendation C (Level of Evidence – 5)

Comments: Radiological methods play a primary role in the diagnosis of anterior diaphragmatic hernias. On plain chest radiographs in two projections, a Morgagni hernia is characterized by a rounded, mesh-like shadow with discrete areas of radiolucency in the right cardiophrenic angle, the intensity of which is lower than the shadow of the adjacent liver and heart. In the lateral projection, the "opacity with areas of radiolucency" is located immediately posterior to the sternum and is superimposed on the cardiac shadow. Sometimes, "gas accumulations" above the diaphragm and haustration typical of the transverse colon are visualized. If the hernia sac contains only the greater omentum, its shadow is homogeneous, without areas of radiolucency.

• Patients with suspected anterior diaphragmatic hernia are recommended to undergo double-contrast upper gastrointestinal series to assess the displacement of gastrointestinal organs above the diaphragm [1].

GCR CLEL 5Grade of Recommendation C (Level of Evidence – 5)

Comments: Contrast imaging of the stomach makes it possible to establish the displacement of a part of it into the hernia sac, which, unlike a paraesophageal hernia, is located in the anterior mediastinum.

Additionally, verification of a Morgagni hernia is performed by filling the displaced transverse colon with a barium suspension 24 hours after contrast administration. In Morgagni hernia complicated by strangulation of the transverse colon, characteristic radiological signs of large bowel obstruction are detected, while in gastric strangulation, there is a delayed evacuation of the barium suspension after 24 hours.

• Patients with suspected anterior diaphragmatic hernia are recommended to undergo lower gastrointestinal series (irrigography) to detect compression of the afferent and efferent segments of the transverse colon in the area of the hernial ring [1].

GCR CLEL 5Grade of Recommendation C (Level of Evidence – 5)

• Patients with suspected anterior diaphragmatic hernia are recommended to undergo computed tomography of the chest cavity to visualize organs displaced into the mediastinum and determine changes in the lungs [1].

GCR CLEL 5Grade of Recommendation C (Level of Evidence – 5)

Diaphragmatic relaxation (eventration)

Diaphragmatic eventration is quite often asymptomatic; therefore, instrumental methods are the only diagnostic modalities.

Physical examination reveals Hoover's sign — a more pronounced inward and upward movement of one of the costal margins during inspiration. Percussion reveals an enlargement and upward displacement of Traube's space. The anterior lower border of the lungs is located at the level of the II–IV ribs, and the border of cardiac dullness is shifted in the opposite direction. Auscultation reveals muffled heart sounds, weakened breath sounds, intestinal sounds and rumbling, or a splashing sound over the chest.

Radiological examination is decisive in the diagnosis of diaphragmatic eventration.

• Patients with suspected diaphragmatic eventration are recommended to undergo plain targeted chest X-ray (fluoroscopy) in two projections to assess X-ray anatomy [1].

GCR CLEL 5Grade of Recommendation C (Level of Evidence – 5)

Comments: Diaphragmatic eventration can be diagnosed using standard radiographs in the posteroanterior and lateral projections. On the affected side, one of the domes of the diaphragm appears elevated. At the same time, there is a persistent rise in the position of the corresponding diaphragmatic dome up to the 2nd–5th ribs; in the supine position, the diaphragm and adjacent abdominal organs are displaced upward; the contour of the diaphragm is a smooth, continuous arched line. In some cases, the diaphragm is so thin that it can be confused with a diaphragmatic hernia. Other observed radiological signs may include mediastinal shift, atelectasis, and high standing of the stomach.

Fluoroscopy is considered the most reliable and informative method for diagnosing diaphragmatic eventration. A characteristic radiological sign is the Alyshevsky-Winbeck sign — paradoxical movements of the diaphragm: elevation during deep inspiration and descent during expiration. Paradoxical movements of the diaphragm are better detected by performing the Müller maneuver — performing a respiratory effort against a closed glottis. In this case, Wellman's sign is observed — multidirectional movement of the diaphragmatic domes on the healthy and affected sides. Breath-holding at the peak of inspiration causes upward displacement of the altered half of the diaphragm due to the retraction force of the lung tissue — the Dillon sign.

• Patients with diaphragmatic eventration are recommended to undergo computed tomography of the chest cavity to visualize changes in the lungs and identify the cause of eventration [35,59–65].

GCR CLEL 5Grade of Recommendation C (Level of Evidence – 5)

Comments: This X-ray imaging method provides complete information about the degree of eventration and the nature of changes in the thoracic and abdominal organs. It should be noted that in all cases of eventration, even with mild severity, atelectasis and inflammatory changes in the basal segments of the lung are observed. Also, CT scanning can reveal a cervical or intrathoracic tumor as a cause of phrenic nerve paralysis or assist in evaluating a subdiaphragmatic process as a cause of diaphragmatic dome elevation [35,59–65].

• Patients with diaphragmatic eventration are recommended to undergo pulmonary perfusion radioisotope scintigraphy to assess the functional state of the lung on the affected side [66,67].

GCR CLEL 5Grade of Recommendation C (Level of Evidence – 5)

Comments: Pulmonary radioisotope scintigraphy (perfusion scintigraphy) in patients with diaphragmatic eventration makes it possible to assess the functional state of the lung on the affected side. This method is based on visualizing the pulmonary arteriocapillary bed using Tc-99m macroaggregated albumin, which, when administered intravenously, temporarily embolizes a small portion of pulmonary precapillaries and arterioles, distributing in proportion to blood flow. A decrease in radiopharmaceutical uptake indicates impaired blood flow in the lung, and the degree of decreased uptake can be used to quantitatively assess perfusion impairment of the lung parenchyma [66,67].

3. Treatment, including drug and non-drug therapies, diet therapy, and pain management

3.1 Congenital diaphragmatic hernia

General principles of treatment include prenatal care, postnatal medical treatment, and surgical correction [1,2,47,48].

3.1.1 Prenatal care

• If a diaphragmatic hernia is detected in the fetus, the pregnant woman is recommended to undergo genetic counseling. Prenatal diagnostics allow for informed counseling of the mother and family, including treatment options and prognosis [2,68–70].

GRC CLEL 4Grade of Recommendation C (Level of Evidence – 4)

Comments: As part of prenatal care, fetal procedures may be used: placement of an occlusive balloon in the fetal trachea using fetoscopy. These balloons are inserted under ultrasound guidance between 24 and 28 weeks of gestation and removed at 34 weeks. Fetal tracheal occlusion for CDH remains an unproven therapy and should only be performed as part of an ongoing randomized trial [69,70]. There are also reports of using medications to reduce pulmonary hypertension in the infant in the postnatal period. Despite promising milestones in research on prenatal medical and pharmacological interventions for CDH, the use of these treatments remains unclear. Currently, there are no indications for any prenatal pharmacotherapy in CDH [2,68].

3.1.2 Conservative Treatment

Conservative treatment includes all types of treatment aimed at stabilizing the patient after birth, preoperative preparation, and the postoperative period. Antibiotic therapy, infusion therapy, and parenteral nutrition are prescribed according to standard methodology [3].

3.1.2.1 Delivery room management

• After birth, a newborn with congenital diaphragmatic hernia is recommended to [3,47,48]:

- undergo endotracheal intubation,

- connect to a mechanical ventilator,

- be warmed,

- undergo peripheral/central venous catheterization,

- gastric tube insertion.

GDR CLE 5Grade of recommendation C (level of evidence – 5)

Comments: In most cases, the presence of CDH in a newborn is already known in advance; therefore, the delivery room team must be prepared to provide specialized care to the newborn. Mask ventilation and non-invasive mechanical ventilation are contraindicated.

It is permissible to use for a short time a catheter placed in the umbilical vein (Umbilical vessel catheterization in newborns). If necessary, resuscitation measures are carried out [27] :

^” This is an off-label drug in newborns. When prescribing, it is necessary to draw up a medical commission conclusion of the healthcare facility in the medical history and obtain the consent of the child's legal representatives for its use.

Further stabilization of the patient is carried out in the ICU setting.

3.1.2.2 Preoperative stabilization and postoperative treatment in the ICU

Further stabilization of each patient with congenital diaphragmatic hernia is carried out in the ICU setting.

• Patients with congenital diaphragmatic hernia are recommended to undergo comprehensive examinations during mechanical ventilation (cardiac monitoring, respiratory monitoring, and analysis of acid-base balance and blood gases) [2,3,47,71].

GDR CLE 5Grade of recommendation C (level of evidence – 5)

Comments:

1. Cardiac monitoring includes:

• Heart rate measurement

• Registration of the electrocardiogram in three standard leads, interpretation, description, and analysis of electrocardiographic data

• Blood pressure measurement on peripheral arteries

2. Respiratory monitoring includes:

• Pulse oximetry (using a skin sensor and recording indicators on the bedside monitor). Pulse oximetry (blood oxygen level testing is performed preductal (right hand) and postductal (left hand, feet).

• Assessment of respiratory function parameters via the ventilator monitor:

  a. Vt (tidal volume),

  b. C (lung compliance),

  c. R (airway resistance),

  d. MAP (mean airway pressure)

• Capnometry ETCO2 (end-tidal carbon dioxide concentration)

3. Analysis of acid-base balance and blood gases (performed on an arterial sample) at least twice a day

• Blood hydrogen ion (pH) testing

• Blood buffer systems testing

• Blood carbon dioxide testing

• Blood oxygen level testing

• Blood lactate level testing

• Blood glucose level testing

4. General thermometry

• Patients with congenital diaphragmatic hernia are recommended to have vascular access established [27].

GRC CLEL 4Grade of Recommendation C (Level of Evidence – 4)

Comments: It is recommended to secure central venous access in every patient for infusion therapy, parenteral nutrition, administration of adrenergic and dopaminergic agents, analgesia, sedation, and antibacterial therapy [3, 47].

• Patients with congenital diaphragmatic hernia are recommended to undergo respiratory support to ensure adequate gas exchange [2,3,47,48,72,73].

GRC CLEL 4Grade of Recommendation C (Level of Evidence – 4)

Comments: Currently, guidelines for mechanical ventilation in CDH patients in the early neonatal period endorse a lung-protective strategy (minimizing barotrauma and volutrauma) using mild permissive hypercapnia and hypoxemia, also known as "gentle ventilation" [4, 5]. Both conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation (HFOV) can be effectively used to provide gentle ventilation in CDH. The goal of respiratory support is to maintain preductal oxygen saturation at 80–95%, postductal above 70%, with PaCO2 ranging from 50 to 70 mmHg.

Recommended ventilation parameters for CMV mode:

Ppeak not exceeding 25 mmHg; PEEP 3–5 mmHg; RR 40–60/min; Vt 6–8 ml/kg. If a Ppeak above 28 mmHg is required to achieve a PaCO2 level of 50–70 mmHg, alternative respiratory strategies such as HFOV or ECMO must be considered [4, 5].

Recommended ventilation parameters for HFOV mode:

1. Frequency (Hz)

= 15 Hz (weight <1000 g)

= 11–14 Hz (weight 1000–2000 g)

= 8–10 Hz (weight >2000 g)

2. Power (ΔP) / amplitude of oscillatory pressure:

Amplitude is calculated by the formula: ΔP = 4 × weight (kg) + 25.

Adequacy of HFOV is monitored radiologically. The appropriateness of the selected parameters can also be assessed by the position of the diaphragm (8th–9th rib).

• Hemodynamic support and treatment of pulmonary hypertension are recommended for all patients with diaphragmatic hernia in whom they are documented [2,3,47,48,71,74,75].

GRC CLEL 4Grade of Recommendation C (Level of Evidence – 4)

Comments: the general condition of a newborn with CDH after birth may remain extremely critical, requiring resuscitation (antishock) measures aimed primarily at maintaining stable hemodynamics [27]

To maintain hemodynamics, adrenergic and dopaminergic agents are used

First-line drugs for maintaining adequate blood pressure are dopamine** and dobutamine**. In case of an inadequate response, as well as in the presence of metabolic acidosis, dopamine** must be replaced with epinephrine**. If there is no response to an increase in the epinephrine** dose, systemic corticosteroids are prescribed: #hydrocortisone** (ATC - H02A). Dosage: 1–2 mg/kg single dose, administered intravenously as a bolus every 6 hours, maximum dose 2–2.5 mg/kg every 4 hours.

If the described therapy is ineffective and normal myocardial contractility is confirmed, norepinephrine** may be used. Dosage: 0.1–0.3 mcg/kg/min, continuous intravenous infusion over 24 hours.

In case of initial (at birth) decompensated acidosis (of any type), the first-line adrenergic and dopaminergic agent will be epinephrine**. Dosage: 0.1–0.5 mcg/kg/min, continuous intravenous infusion over 24 hours.

Resistant hypotension, including cases requiring infusion of high doses of adrenergic and dopaminergic agents, is an indication for venoarterial ECMO (VA-ECMO).

Pulmonary hypertension is a common and severe complication in infants with CDH.

The first-line drug for the treatment of pulmonary hypertension is nitric oxide**.

Inhalation of nitric oxide** is performed during conventional mechanical ventilation or HFOV by delivering the gas mixture directly into the patient circuit (via an additional port in the endotracheal tube connector or breathing circuit).

Monitoring of inhaled gases is mandatory to continuously measure the concentrations of NO and NO₂, with automatic gas shutoff if NO or NO₂ concentrations exceed permissible limits.

Prostaglandin E₁ (#Alprostadil**)^” (Prostaglandins (C01EA)) [27]

The purpose of administration is to maintain patent ductus arteriosus to facilitate right-to-left shunting, reduce pulmonary hypertension, and alleviate right ventricular heart failure. Dosage: 0.005–0.01 mcg/kg/min continuous intravenous infusion over 24 hours.

Duration of therapy is determined by the dynamics of pulmonary hypertension.

Phosphodiesterase-5 (PDE5) inhibitors – #Sildenafil” (Phosphodiesterase inhibitors, C01CE) [27]

Phosphodiesterase inhibitors are cyclic guanosine monophosphate (cGMP) modulators that target vascular remodeling by limiting smooth muscle cell proliferation. #Sildenafil is most active against visceral and vascular smooth muscles and is used alone or with nitric oxide to treat PH. Dosage: 1 mg/kg/day divided into 4 doses via a gastric tube (orally), maximum dose 3 mg/kg/day.

Antihypertensive agents for the treatment of pulmonary arterial hypertension C02KX – #Bosentan** [27]

#Bosentan** acts on endothelin-1 by reducing its concentration and decreases PH; dosage is 4 mg/kg/day divided into 2 doses via a gastric tube (orally)

Cardiotonic agents excluding cardiac glycosides C01C – #Levosimendan**”[27]

It opens ATP-sensitive K+ channels in vascular smooth muscle, thereby causing relaxation of systemic and coronary arteries and veins. It is a selective phosphodiesterase 3 inhibitor (C01CE). #Levosimendan**” continuous intravenous infusion over 24 hours at 0.1 mcg/kg/min.

#” Classified as an off-label drug in neonates. When prescribing, it is necessary to issue a medical commission report of the healthcare institution and obtain informed consent from the child's legal representatives for its use.

Extracorporeal membrane oxygenation (ECMO)

• ECMO is recommended for patients with congenital diaphragmatic hernia with progressive respiratory and cardiac failure when conservative therapy fails [47,48,76–78].

GDR CLE 5Grade of recommendation C (level of evidence – 5)

Comments: ECMO is a complex of devices that allows blood oxygenation bypassing the lungs. Indications for ECMO initiation are determined by the severity of respiratory and hemodynamic disorders, concomitant pathology, and the duration of prior respiratory support [27]:

The oxygenation index is used to determine indications for ECMO.

The oxygenation index is calculated using the following formula:

OI = (MAP × FiO₂ / PaO₂) × 100, where

MAP is the mean airway pressure if the child is on conventional ventilation, or CDP during HFOV.

FiO₂ – fractional concentration of inspired oxygen

PaO₂ – partial pressure of oxygen in the patient's arterial blood.

An oxygenation index greater than 25 is an indication for ECMO

Contraindications to ECMO:

- significant associated congenital anomalies (complex congenital heart defects or CNS malformations)

- lethal chromosomal anomalies (trisomy 18) or other lethal congenital malformations

- grade III-IV intracranial hemorrhage

- body weight less than 1800 g

- gestational age less than 32–34 weeks

- prolonged (more than 7 days) mechanical ventilation with high pressures (MAP >15–18 mmHg).

• Patients with congenital diaphragmatic hernia are recommended to undergo evaluation of readiness for surgical treatment every 24 hours [3,47,48].

GDR CLE 5Grade of recommendation C (level of evidence – 5)

Comments: The timing of preoperative preparation is determined by the child's condition. Surgery in children with CDH is performed on an emergency basis if stable parameters are maintained for 24 hours:

- stable oxygenation: SpO₂ >94% at FiO₂ 0.5–0.6

- heart rate within age-appropriate normal limits; mean arterial pressure within age-appropriate normal limits and higher than right ventricular pressure;

- degree of pulmonary hypertension with decreased or systemic arterial pressure levels according to echocardiography, without pulmonary hypertensive crises;

- diuresis ≥2 ml/kg/h;

- acid-base balance values: pH not lower than 7.2, pCO₂ not higher than 65 mmHg, lactate not higher than 3 mmol/L).

• Patients with congenital diaphragmatic hernia are recommended to undergo surgical treatment using balanced general anesthesia [48,79].

GDR CLE 5Grade of recommendation C (level of evidence – 5)

Comments: If the child is on "rigid" mechanical ventilation settings, high-frequency oscillatory ventilation (HFOV), receives inhalation of nitrous oxide** or high doses of adrenergic and dopaminergic agents, the issue of performing the surgery in the resuscitation room – "at the bedside" – should be considered.

Total intravenous anesthesia or its combination with inhalation anesthesia is most commonly used. Inhalation of nitrous oxide** is contraindicated

During surgery, the infusion of adrenergic and dopaminergic agents that were administered prior to surgery is continued.

• Patients with congenital diaphragmatic hernia in the absence of contraindications may undergo epidural block [27]

GRC CLEL 4Grade of Recommendation C (Level of Evidence – 4)

Comments: Epidural block is performed for postoperative analgesia. For pain management, a 0.2% ropivacaine** solution is used at a dose of 0.2 mg/kg/h continuous infusion into the epidural space for up to 72 hours.

Prevention and treatment of infectious complications are carried out in accordance with the antibiotic therapy protocol for newborns in the NICU and surgery department. Correction and prescription of antibacterial drugs are recommended for all patients with diaphragmatic hernia based on laboratory test results.

3.1.3 Surgical treatment

• Patients with congenital diaphragmatic hernia are recommended to undergo surgical treatment to restore the integrity of the diaphragm and demarcate the thoracic and abdominal cavities once a stable condition is achieved. The surgery can be performed via an endoscopic or open approach. If there is a deficiency of native diaphragmatic tissues, implant material must be used [1,2,27,38,80–87].

GRC BLEL 2Grade of Recommendation B (Level of Evidence – 2)

Comment: There are two general approaches to surgical repair of the diaphragmatic defect in CDH: open or minimally invasive. Within these broad categories, there are several subcategories.

Open CDH repair can be performed using a thoracic or abdominal approach. The advantages of laparotomy include easier relocation of internal organs from the thoracic cavity into the abdominal cavity, the ability to mobilize the posterior edge of the diaphragm, easier management of intestinal rotational anomalies (if necessary), and prevention of musculoskeletal complications associated with thoracotomy. The vast majority of open neonatal CDH interventions are performed through a subcostal incision, but laparotomy is also possible. For right-sided CDH, thoracotomy is more frequently used. The true hernia sac should be excised. The thoracic and abdominal cavities should be inspected for associated pulmonary sequestration. Special attention should be paid to peak inspiratory pressure when closing the abdominal fascia. In the event of respiratory failure, the surgeon should consider temporary closure of the abdominal cavity with the formation of a ventral hernia or closing the surgical wound with a skin flap only. Leaving a drain in the pleural cavity is not mandatory.

The endoscopic approach can be used in patients with stable hemodynamics. In questionable cases, the test to determine the feasibility of endoscopic correction is to turn the child onto the healthy side and observe the change in saturation levels for 5–10 minutes. If the child's condition is unstable, the patient is placed in the supine position and a laparotomy is performed. Thoracoscopic correction is the most frequent approach used for both left- and right-sided hernia localization. Laparoscopy is currently very rarely used for primary repair.

In any case, the principle of surgical intervention consists of two stages: relocation of organs from the thoracic cavity into the abdominal cavity and closure of the diaphragmatic defect. For type A and B defects, closure can be achieved by placing sutures on the edges of the defect; for type B, it is recommended to perform a through lateral suture. For type C and D defects, native tissues are insufficient for closure. Therefore, it is recommended to use an implant (porous and non-porous perforated polytetrafluoroethylene film for the surgical treatment of hernias of various locations by laparoscopic and traditional methods, sterile). To close the defect and prevent recurrence, complete mobilization of the posterior lip of the diaphragmatic defect must be performed, and if absent, the implant should be fixed to the rib.

3.1.4 Postoperative period

• Patients with congenital diaphragmatic hernia in the postoperative period are recommended to receive pain management [27]

GRC CLEL 4Grade of Recommendation C (Level of Evidence – 4)

Comments: For postoperative pain management, epidural analgesia (see above) or intravenous opioid analgesia is used. For intravenous analgesia, #Fentanyl**” 0.005% solution is used. Dosage: 5 mcg/kg intravenous continuous infusion over 24 hours, #Morphine hydrochloride**” 1% solution. Dosage: 10–15 mcg/kg/h intravenous continuous infusion over 24 hours. The duration of postoperative pain management is 5 days.

• Patients with congenital diaphragmatic hernia in the postoperative period are recommended to undergo monitoring for complications [1–3,71]:

- chylothorax;

- wound infection;

- gastroesophageal reflux;

- recurrence of CDH.

GDR CLE 5Grade of recommendation C (level of evidence – 5)

Comments: The peak of fluid accumulation in the pleural cavity occurs on days 2–5 after surgery. Subsequent resorption of the fluid takes place on days 5–10 after surgery [27].

Postoperative chylothorax occurs in approximately 20% of newborns in the postoperative period following diaphragmatic repair and may serve as an indication for pleural cavity drainage. To diagnose chylothorax, pleural effusion is analyzed (lymphocytes predominate at over 80%, protein content corresponds to blood plasma, and the levels of triglycerides and beta-lipoproteins are elevated). The main principles of conservative therapy for chylothorax include continuous intravenous infusion of #octreotide** at a starting dose of 5 mcg/kg/h with a dose escalation of 5 mcg/kg/h every 24–48 hours [27] in the absence of a decrease in pleural drain output, and switching to a specialized dietary medical nutrition product for children from birth and adults with long-chain fatty acid oxidation defects, chylothorax, and lymphangiectasia "Monogen" (in case of fatty acid metabolism disorders)****.

Enteral feeding is initiated after the complete restoration of gastrointestinal tract passage. Breast milk is preferred, administered continuously via a gastric tube, gradually increasing the feeding volume. Following extubation and stabilization of the patient's general status, a gradual transition to breastfeeding or formula feeding is made. Specialized nutrition is generally not required for patients with DH.

3.1.5 Other treatment

No other treatment is provided

3.2 Hiatal hernia

3.2.1 Conservative Treatment

• Patients with a diagnosed hiatal hernia are not recommended to receive conservative therapy as the primary treatment method [1].

GCR CLEL 5Grade of Recommendation C (Level of Evidence – 5)

Comments: Conservative and drug therapy for diagnosed hiatal hernia is not indicated because these methods aim to prevent and treat GERD rather than eliminate the hiatal hernia itself. If there are contraindications to surgical treatment of hiatal hernia, conservative and medical management includes elevating the child's position immediately after feeding and during sleep, diet and frequent small meals, administration of drugs that increase the tone of the lower esophageal sphincter (prokinetics), and agents that reduce the aggressiveness of gastric contents (antacids, H2-blockers, proton pump inhibitors). Conservative therapy is recommended in the preoperative period to treat GERD complications.

3.2.2 Surgical treatment

• Patients with a diagnosed hiatal hernia are recommended surgical treatment: laparoscopic hiatal hernia repair and fundoplication [39, 58, 88–91].

GRC CLEL 4Grade of Recommendation C (Level of Evidence – 4)

Comment: The indication for surgical treatment is all forms of hiatal hernia presenting with a severe clinical picture and peptic complications. In peptic esophageal stenosis, surgery is advisable after complete elimination of the stenosis by bougienage combined with medical therapy. Preoperative preparation aims to eliminate the consequences of pathological gastroesophageal reflux: malnutrition, pneumonia, anemia.

In endosurgical treatment of hiatal hernias in children, Nissen fundoplication, first described in 1956, has gained the greatest popularity. Currently, this operation is used in children of any age. According to many authors, Nissen fundoplication yields positive results in 85–90% of children. The operation consists of laparoscopic correction of the hiatal hernia, excision of the hernia sac, and gastrofundoplication. The main advantage of laparoscopic operations for hiatal hernia correction is the possibility of re-interventions without particular technical difficulties associated with adhesions in the abdominal cavity. Laparoscopic hiatal hernia repair is feasible in children regardless of age and body weight, for any malformations, and in case of disease recurrence. The possibility of laparoscopic hiatal hernia correction after previously performed open surgeries is particularly important, ensuring minimal invasiveness and good outcomes.

Surgical technique:

Laparoscopic correction of hiatal hernia must adhere to the principles of traditional (open) surgery. The main stages of the operation are:

• reduction of the stomach and the abdominal esophagus;

• excision of the hernia sac;

• suturing of the crura of the diaphragm (hiatoplasty) and suturing of the esophagus to the diaphragm along the perimeter;

• mobilization of the gastric fundus and cardia;

• creation of a 1.5–2 cm Nissen wrap.

On the operating table, the child is placed with the foot of the table tilted down by 10–15°. Five trocars are inserted into the abdominal cavity (similar to laparoscopic Nissen fundoplication): the 1st trocar is placed through the umbilicus (endoscope); the 2nd trocar is in the right hypochondrium; the 3rd trocar is below the xiphoid process; the 4th trocar is in the left hypochondrium; the 5th trocar is in the left iliac region.

Depending on the patient's age and weight, 3.5 and 5 mm trocars are used. The first trocar (diameter 4.7 mm) is inserted transumbilically using the open laparoscopy method. Carbon dioxide is insufflated through it into the abdominal cavity (pressure 10–14 mm Hg). An endoscope with 30° forward-oblique optics (diameter 4 mm) is inserted through the same trocar. After establishing the capnoperitoneum, the remaining 4 trocars for 3 or 5 mm endo-instruments are inserted into the abdominal cavity. After inspecting the abdominal cavity, the stomach and the abdominal esophagus are reduced into the abdominal cavity. In paraesophageal hiatal hernia, the hernia sac must be completely excised.

Laparoscopic correction of hiatal hernia must always adhere to the following rules:

• minimal mobilization of the abdominal esophagus and cardia;

• preservation of the hepatoesophageal ligament and vagus nerve branches supplying the liver to prevent postoperative biliary dyskinesia;

• complete excision of the hernia sac;

• fixation of the esophagus to the diaphragm with interrupted sutures;

• mobilization of the gastric fundus with division of short gastric vessels over a short distance (1–3 short gastric vessels);

• creation of a 1.5–2 cm antireflux wrap.

3.2.3 Postoperative management

The postoperative period after laparoscopic hiatal hernia repair does not differ from that after other laparoscopic procedures. Discharge from the hospital can be planned when the single feeding volume reaches the age norm and the general condition is satisfactory. Follow-up examinations (contrast radiography, EGD) are not performed in the absence of complaints and dysphagia during feeding. The results of surgical treatment are evaluated 6 months after surgery [92].

3.3 Anterior diaphragmatic hernia

3.3.1 Surgical treatment

• Patients with an anterior diaphragmatic hernia are recommended surgical treatment: laparoscopic hernia repair with excision of the hernia sac [93–95].

GCR ALEL 3Grade of Recommendation A (Level of Evidence – 3)

Comment: Treatment of anterior diaphragmatic hernias is exclusively surgical. In the global surgical community, the most controversial aspect of anterior diaphragmatic hernia repair is the choice of surgical approach. Currently, there is a trend toward using minimally invasive methods.

Most colleagues prefer the laparoscopic approach, noting its advantages:

• relative simplicity and safety

• good visualization of both diaphragmatic domes

• ability to dissect adhesions between the omentum and organs

• low rate of conversions and complications [95–97].

The laparoscopic technique additionally helps reduce tissue trauma, the need for postoperative analgesia, and shorten hospital stay and rehabilitation periods [93].

The thoracoscopic approach, which provides the ability to more precisely dissect intrathoracic adhesions, has several disadvantages: the existing risk of missing a bilateral hernia, as well as less optimal working conditions during the excision of the hernia sac. All this limits the use of this approach in the treatment of patients with anterior diaphragmatic hernias [94].

Open techniques for anterior diaphragmatic hernia repair are currently becoming less relevant, although it is worth noting the optimality of the transsternal approach in cases of simultaneous repair of an anterior diaphragmatic hernia and associated congenital heart disease [98].

Excision of the hernia sac is a mandatory step of the operation to avoid cyst formation in the remaining cavity and to prevent disease recurrence. Concerns related to the excision of the hernia sac are due to the possibility of intraoperative complications such as pneumothorax and pneumomediastinum with respiratory or circulatory disorders, damage to the pericardium and mediastinal structures [95]. However, some surgeons prefer to leave the hernia sac in situ, citing a lack of evidence regarding a correlation between recurrence rates and leaving the sac [94]. Proponents of leaving the hernia sac also note reduced operative time and a lower risk of intraoperative complications, such as bleeding from adhesions, damage to the phrenic nerve, pericardium, and pleura [26, 99].

The most optimal method of diaphragmatic plication consists of placing buried U-shaped interrupted sutures that pass through the anterior abdominal wall (chest wall in the case of thoracoscopy) and fix the diaphragm to it. In some cases, additional fixation of the diaphragm to the rib can be used. Along with U-shaped sutures [27, 28, 100], some prefer horizontal mattress sutures, considering them more reliable [98, 101].

Mesh grafts in diaphragmatic repair for children with anterior diaphragmatic hernias are rarely used [96, 102]. However, Y.W. Tan et al. associate the use of meshes with a reduced risk of recurrence [94]. Postoperative complications associated with autologous diaphragmatic repair are known: pulmonary hypertension and respiratory failure, development of hemopneumothorax [103]. Several researchers have noted recurrence after closure of Morgagni-Larrey hernia in 2.8–5.7% of cases regardless of open and minimally invasive interventions, with a reduction in complications when using mesh [29, 102].

3.4 Diaphragmatic eventration

3.4.1 Conservative treatment

Treatment of diaphragmatic eventration depends on the severity of respiratory distress syndrome. It usually begins with conservative therapy aimed at supporting cardiac function and adequate pulmonary ventilation. In addition to continuous oxygenation, positive end-expiratory pressure breathing is periodically performed. If ineffective, assisted or mechanical ventilation is initiated. If no effect is observed after 2–3 weeks, surgical treatment is performed.

3.4.2 Surgical treatment

• Patients with diaphragmatic relaxation are recommended surgical treatment – thoracoscopic diaphragmatic plication [1,104–110].

GOP ALOE 3Grade of recommendation A (level of evidence – 3)

Comments: The objective of the surgical intervention is to restore the initial standing level of the diaphragm, as a result of which the thoracic and abdominal organs should assume their normal position. The operation consists of diaphragmatic plasty using native tissues. Among various methods of diaphragmatic plasty with native tissues, phrenoplication is the most widely used – the formation of a duplication from a fold of the diaphragm or from its two fragments after resection of the thinned area of the diaphragm. In this method, the dome of the diaphragm is pulled out enough to ensure the normal position of the diaphragm. Then, the resulting flap is fixed with several rows of sutures to the chest wall and the diaphragm. However, such an operation can be effective only if the trophic properties of the diaphragmatic muscle are preserved, as a rule, in the early stage of relaxation or in its limited form. In cases of pronounced relaxation and thinning of the entire dome of the diaphragm, the duplicative method of diaphragmentoplasty does not guarantee the absence of disease recurrence.

A modern and promising direction in diaphragmatic surgery is thoracoscopic surgery for diaphragmatic relaxation. The well-known advantages of endoscopic operations – primarily minimal damage to the respiratory muscles of the chest wall – acquire special significance here, since any of the previously described types of diaphragmatic plasty cannot restore the function of this main respiratory muscle, but only creates a motionless cardiophrenic partition. Even after a successfully performed and effective operation, respiratory movements are carried out by the auxiliary respiratory muscles, and therefore the maximum possible preservation of the intercostal muscles, which is provided by the thoracoscopic approach, is extremely important.

4. Medical Rehabilitation and Sanatorium-Resort Treatment

In the postoperative period, all patients who have undergone surgery for congenital diaphragmatic hernia require rehabilitation therapy aimed at restoring respiratory function. After discharge from the hospital, follow-up by a pediatrician, surgeon, and pulmonologist is necessary. In the presence of concomitant diseases, follow-up by a subspecialist is required.

5. Prevention and Dispensary Observation

There is no specific prophylaxis for CDH. Prophylaxis of disease recurrence consists of a protective regimen after discharge from the hospital for 3 months.

Comment: patient examination includes:

- prescription of chest radiography in direct and lateral (pathological) projections at the age of 3 months, 6 months, 12 months regardless of the patient's condition

- prescription of chest radiography for prolonged cough, during an acute respiratory viral infection (ARVI), as well as for any conditions suspected of causing recurrence (shortness of breath, impaired intestinal transit, fatigue, etc.) at any age

- prescription of computed tomography of the chest cavity with intravenous bolus contrast enhancement in case of a doubtful radiological picture

Dispensary follow-up by a pulmonologist for patients with severe pulmonary hypertension, bronchopulmonary dysplasia, and bronchial obstruction.

Respiratory infections have a higher prevalence in children with CDH. Respiratory syncytial virus (RSV) is the most common pathogen observed in children aged <3 years, suggesting the need for RSV prophylaxis.

Obstructive pulmonary disease is frequently reported in CDH survivors. Although symptoms appear to improve with age, most CDH children will experience some combination of obstructive and restrictive lung function, as well as increased reactivity to pharmacological agents, even by self-report. This decline in lung function is most likely due to lower functional volumes rather than primary airway obstruction.

Long-term neurodevelopmental outcomes in CDH survivors make up a significant portion of overall morbidity data. Although harder to detect, residual neurological disorders are increasingly identified in long-term studies. Poorer neurodevelopmental outcomes have also been associated with greater CDH severity, need for ECMO, and associated chromosomal abnormalities.

6. Organization of Medical Care

Treatment of patients with congenital diaphragmatic hernia is carried out in a multidisciplinary children's hospital or in a perinatal center that has significant positive experience and all the listed methods of diagnosis, treatment, and rehabilitation of patients. Care for patients with CDH is provided by pediatric surgeons and anesthesiologists-resuscitators experienced in treating children. Hospitalization of patients is carried out on an emergency basis in a stable condition.

Indication for hospitalization:

• confirmed diagnosis of congenital diaphragmatic hernia

Indications for patient discharge:

• with steady improvement, when the patient can stay outside the hospital without detriment to health

• if there is a need to transfer the patient to another medical institution;

• at the request of the patient or their legal representative;

7. Additional Information

Negative factors affecting treatment outcomes include:

1. Development of infectious complications;

2. Malignant pulmonary hypertension;

3. Associated congenital heart defects;

4. Chromosomal abnormalities and genetic pathology;

5. Premature labor.

Criteria for Evaluating the Quality of Medical Care

Congenital diaphragmatic hernia

Hiatal hernia

References

Appendix A1. Working Group Composition

1. Razumovsky Alexander Yuryevich – Corresponding Member of the RAS, Doctor of Medical Sciences, Professor, Head of the Department of Pediatric Surgery named after Yu.F. Isakov, Pirogov Russian National Research Medical University (RNRMU), Chief Pediatric Surgeon of the Moscow Healthcare Department, Chief Pediatric Surgeon of the Central Federal District of the Russian Federation, Head of the Department of Thoracic Surgery and Surgical Gastroenterology, Filatov Children's City Clinical Hospital (Moscow). Chairman of the Presidium of the Russian Association of Pediatric Surgeons, Board Member of the Moscow Society of Surgeons, Board Member of the Russian Society of Endoscopic Surgeons, Board Member of the Russian Society of Surgical Gastroenterologists, Member of the European Association of Pediatric Surgeons and the Russian Association of Hepatobiliary Surgeons.

2. Mitupov Zorikto Batoevich – Doctor of Medical Sciences, Professor at the Department of Pediatric Surgery named after Yu.F. Isakov, Institute of Maternity and Childhood, Pirogov Russian National Research Medical University (RNRMU), Thoracic Surgeon, Filatov Children's City Clinical Hospital (Moscow). Chairman of the Problem Commission on Thoracic Surgery of the Russian Association of Pediatric Surgeons.

3. Afukov Ivan Igorevich – Candidate of Medical Sciences, Chief Freelance Pediatric Specialist Anesthesiologist-Resuscitator of the City of Moscow, Chief Physician of Speransky Children's City Clinical Hospital No. 9 (Moscow), Associate Professor at the Department of Pediatric Surgery, Pirogov Russian National Research Medical University of the Russian Ministry of Health.

4. Burov Artem Alexandrovich – Candidate of Medical Sciences, Anesthesiologist-Resuscitator, Neonatologist, Head of Clinical Work at the Department of Neonatal Surgery, Kulakov National Medical Research Center for Obstetrics, Gynecology and Perinatology of the Russian Ministry of Health (Moscow).

5. Gorelik Konstantin Davydovich – Head of the Neonatal Intensive Care Unit No. 39, Children's City Multidisciplinary Clinical Specialized Center for High Medical Technologies (Saint Petersburg), Assistant Professor at the Department of Pediatric Surgery with a Course in Resuscitation, Pavlov First Saint Petersburg State Medical University of the Russian Ministry of Health.

6. Zilbert Elena Vitalievna – Candidate of Medical Sciences, Head of the Intensive Care Unit, Anesthesiologist-Resuscitator, Filatov Children's City Clinical Hospital (Moscow).

7. Ivanov Sergey Lvovich – Head of the Neonatal Intensive Care Unit No. 39A, Children's City Multidisciplinary Clinical Specialized Center for High Medical Technologies (Saint Petersburg).

8. Karavaeva Svetlana Alexandrovna – Doctor of Medical Sciences, Professor, Head of the Department of Pediatric Surgery, Saint Petersburg Medical Academy of Postgraduate Studies (SPbMAPO), Lead Operating Surgeon, Children's City Multidisciplinary Clinical Specialized Center for High Medical Technologies (Saint Petersburg). Chairman of the Problem Commission on Neonatal Surgery of the Russian Association of Pediatric Surgeons.

9. Kotin Alexey Nikolaevich – Candidate of Medical Sciences, Associate Professor at the Department of Pediatric Surgery with a Course in Anesthesiology and Resuscitation, Pavlov First Saint Petersburg State Medical University, Lead Operating Surgeon of the Neonatal Surgery Service, Children's City Multidisciplinary Clinical Specialized Center for High Medical Technologies (Saint Petersburg). Member of the Russian Association of Pediatric Surgeons.

10. Olga G. Mokrushina – Doctor of Medical Sciences, Professor at the Department of Pediatric Surgery named after Yu.F. Isakov, Institute of Maternity and Childhood, Pirogov Russian National Research Medical University; Deputy Chief Physician for Surgery, Filatov Children's City Clinical Hospital of the Moscow Healthcare Department (Moscow). Member of the Russian Association of Pediatric Surgeons.

11. Sergey M. Stepanenko – Doctor of Medical Sciences, Professor at the Department of Pediatric Surgery named after Yu.F. Isakov, Institute of Maternity and Childhood, Pirogov Russian National Research Medical University; Chief Freelance Pediatric Anesthesiologist-Resuscitator of the Ministry of Health of the Russian Federation.

12. Vadim O. Teplov – Candidate of Medical Sciences, Pediatric Surgeon, Endoscopist at the Pediatric Endoscopic Center, Filatov Children's City Clinical Hospital of the Moscow Healthcare Department (Moscow). Member of the Russian Association of Pediatric Surgeons.

There is no conflict of interest.

Appendix A2. Methodology for Developing Clinical Guidelines

Target audience of the clinical guidelines:

1. Pediatric surgeons

2. Anesthesiologists-resuscitators

3. Neonatologists

4. Pediatricians

5. Obstetricians-gynecologists

6. Functional diagnostics physicians

7. Geneticists

8. Mid-level medical personnel

9. Healthcare organizers

11. Medical university students, residents, postgraduate students.

In these clinical guidelines, all data are ranked by level of reliability (evidence) depending on the quantity and quality of studies on the issue.

Table 1. Scale for grading levels of evidence (LE) for diagnostic methods (diagnostic interventions)

Table 2. Scale for grading levels of evidence (LE) for prevention, treatment, and rehabilitation methods (preventive, therapeutic, and rehabilitative interventions)

Table 3. Scale for grading the levels of evidence for prevention, treatment, and rehabilitation methods (preventive, diagnostic, therapeutic, and rehabilitative interventions)

Procedure for updating clinical guidelines

The clinical guideline update mechanism provides for systematic revision at least once every three years, as well as upon the emergence of new evidence-based data regarding the diagnosis, treatment, prevention, and rehabilitation of specific diseases, or when justified additions/comments to previously approved clinical guidelines arise, but no more frequently than once every 6 months.

Appendix A3. Reference Materials

Related documents

These clinical guidelines were developed taking into account the following regulatory legal documents:

1. Article 76 of Federal Law No. 323-FZ of the Russian Federation dated November 21, 2011, "On the Fundamentals of Public Health Protection in the Russian Federation", regarding the development and approval of clinical guidelines (treatment protocols) for the provision of medical care by medical professional non-profit organizations;

2. Federal Law of the Russian Federation No. 326-FZ dated November 29, 2010, "On Compulsory Medical Insurance in the Russian Federation";

3. Order of the Russian Ministry of Health No. 203n dated May 10, 2017, "On Approval of Criteria for Assessing the Quality of Medical Care";

4. Order of the Ministry of Health and Social Development of the Russian Federation No. 585n dated August 27, 2019, "On Classifications and Criteria Used in Medical and Social Expertise of Citizens by Federal State Institutions of Medical and Social Expertise";

5. Federal Law No. 178-FZ dated July 17, 1999, "On State Social Assistance".

Appendix B. Physician Action Algorithms

Appendix C. Patient Information

Congenital diaphragmatic hernia is a malformation that develops in early pregnancy. The diaphragm develops from the fusion of four embryonic components: anteriorly – the septum transversum; posterolaterally – the pleuroperitoneal folds; centrally – the crura of the esophageal mesentery; and posteriorly – the body wall mesoderm. After the fusion of all parts, a septum forms between the thoracic and abdominal cavities. In some cases, a communication between the thoracic and abdominal cavities persists along the lower border of the posterior part of the ribs. Most frequently, this communication forms on the left side. Inadequate closure of the pleuroperitoneal canal allows abdominal organs located beneath the defective dome to protrude into the thoracic cavity. On the left side, these are intestinal loops, stomach, spleen, and the left lobe of the liver. On the right side, the right lobe of the liver and intestines. Organs displaced into the thoracic cavity cause compression of the lungs and cardiac chambers. This leads to impaired development of lung tissue and also causes dysfunction of the cardiac chambers. The most unfavorable situation occurs when solid (parenchymatous) organs, such as the liver and spleen, are displaced. However, due to its small size, displacement of the spleen does not play a significant role. Under compression, lung tissue does not develop fully. Blood vessels are primarily affected; under adverse conditions of lung development, they are unable to change their diameter. Therefore, pulmonary capillaries on the affected side have a very narrow lumen and a very thick wall. This structure leads to impaired blood flow in the capillaries, and as a consequence, blood oxygen saturation decreases. This pathological condition is called pulmonary hypertension. Combating pulmonary hypertension is a complex challenge in the treatment of patients with a diaphragmatic hernia. Another pathological process that develops with this malformation is a reduction in the size of the cardiac chambers, as they cannot achieve sufficient volume due to cardiac compression by organs displaced from the abdomen into the chest. The small volume of the cardiac chambers leads to impaired blood circulation in the child's organs and tissues. This pathological condition is called heart failure. The treatment of heart failure, as well as combating pulmonary hypertension, is the basis of treatment for patients with a diaphragmatic hernia. Given that about 30% of patients with a diaphragmatic hernia may have chromosomal abnormalities and genetic syndromes, a mother must undergo genetic screening. The birth of a child with a diaphragmatic hernia should take place in a specialized maternity hospital where staff can provide correct first aid to the patient after birth. The child must also be treated and operated on in a specialized medical institution with significant positive experience in treating such patients. Surgical interventions are performed after the child's condition is stable. An unstable child must not be operated on. Currently, surgical interventions can be performed in 2 ways: open and endoscopic. The choice of surgical approach depends both on the patient's condition and on the experience of the surgeon performing the procedure. For uncomplicated hernias, when the patient's condition permits, endoscopic surgery is the preferred treatment method. In any case, surgical interventions are aimed at restoring the integrity of the diaphragm and separating the thoracic and abdominal cavities. However, treatment for children with a diaphragmatic hernia does not end there, as pulmonary hypertension can also develop in the postoperative period. Today, survival rates for patients with a diaphragmatic hernia in specialized centers are 70–80%. The survival prognosis worsens if the liver is located in the pleural cavity, if the child has a congenital heart defect, if the child was born premature, or if there are other comorbid conditions that independently worsen the patient's general condition. After surgery, the child is placed in the intensive care unit, where care and treatment for cardiopulmonary failure are continued. Once the child is able to breathe independently, they are transferred to the surgical department, where the child stays with their mother. Gradually, enteral feeding is initiated and increased, and the child is eventually discharged home. The child is discharged home when they can safely stay outside the hospital environment. Among complications in the postoperative period, the most dangerous is recurrence of the diaphragmatic hernia; therefore, children who have undergone diaphragmatic hernia repair must be monitored by a local pediatrician and surgeon and periodically undergo chest X-rays so that a recurrence can be detected even in the absence of clinical symptoms. Recurrence of a diaphragmatic hernia must also be treated surgically. As a rule, children tolerate repeat surgery much better than the initial reconstruction.

Appendix G. Assessment Scales, Questionnaires, and Other Evaluation Tools

None provided.