Indications and contraindications for enemas

The role of enemas in preoperative preparation

The preoperative period lasts from the moment of diagnosis until the patient is transferred to the operating room. The main goal of this stage is to minimize the risk of intraoperative and postoperative complications. Bowel cleansing is an integral part of immediate preparation for elective surgical interventions.

In general surgery, a cleansing enema is administered on the eve of elective surgery. Colon surgeries require special attention, involving special preparation: the patient is prescribed a residue-free diet, antibacterial drugs, and multiple cleansing enemas until "clear water" is obtained.

In obstetric practice, when preparing for an elective cesarean section, a cleansing enema is performed on the morning of the surgery. In an emergency cesarean section, the procedure is permissible, but exclusively in the complete absence of contraindications.

Absolute contraindications

Despite its apparent simplicity, introducing fluid into the rectum increases intraluminal pressure. In the presence of tissue inflammation or ischemia, this can lead to iatrogenic bowel perforation.

Cleansing enemas are strictly contraindicated in:

• Acute abdominal conditions (acute appendicitis, cholecystitis, pancreatitis).
• Perforated gastric or duodenal ulcer.
• Acute intestinal obstruction and strangulated hernias.
• Life-threatening obstetric conditions: massive hemorrhage (e.g., in placental abruption) and impending or completed uterine rupture before an emergency cesarean section.

Enemas in neonatology: Hirschsprung's disease

Normally, meconium is passed in term newborns within the first 24–48 hours. Delayed stool passage can be a sign of Hirschsprung's disease—a neurocristopathy characterized by impaired neuroblast migration, where parasympathetic ganglia are absent in the Auerbach and Meissner plexuses of the distal bowel. This causes functional low intestinal obstruction.

In the neonatal period, the disease manifests with abdominal distension and vomiting. In such cases, regular cleansing enemas are used therapeutically to temporarily relieve symptoms and facilitate the passage of accumulated meconium.

Strict rules for performing a contrast enema

For the radiodiagnosis of Hirschsprung's disease and determining the length of the affected (aganglionic) segment prior to biopsy, a contrast enema is used. Its sensitivity is 70% and specificity is 83%. To avoid complications and obtain a reliable radiograph, a strict protocol is followed:

1. No preparation: the bowel is not pre-cleaned.
2. Time interval: the procedure is performed no earlier than 48 hours after the last cleansing enema or rectal examination.
3. Insertion technique: the catheter tip is inserted shallowly. It is strictly forbidden to inflate the catheter balloon! An inflated balloon can mask diagnostic signs of the transition zone or rupture the rigid wall of the aganglionic bowel.

The most informative image is taken in a lateral (oblique) projection with slow filling of the bowel with contrast. Characteristic signs of short-segment disease include a narrowed rectum, a cone-shaped transition zone, and an inverted rectosigmoid index (becoming <1, whereas normally the rectum is wider than the sigmoid colon).

Important: If the child presents with clinical signs of severe Hirschsprung's enterocolitis (bloody diarrhea, sepsis, shock), performing a contrast enema is absolutely contraindicated.

Class and exam questions

What else to study on this topic

• General and special preoperative preparation
• Premedication: emergency and elective preparation regimens
• Pathogenesis and histology of Hirschsprung's disease
• Differential diagnosis of neonatal intestinal obstruction
• Preparation for emergency cesarean section and prevention of Mendelson's syndrome

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.