Postoperative Complications

Timing of pathological conditions

All pathologies developing after surgery are traditionally classified by the time of their clinical manifestation. This helps the surgeon maintain vigilance on specific days.

Early period (first 2 days). During this time, the patient is most vulnerable. The following conditions are most frequently diagnosed:

• Internal or external hemorrhage.
• Acute vascular failure (shock) and acute heart failure.
• Asphyxia and pronounced respiratory failure, as well as specific complications from the administered anesthesia.
• Sharp disturbances of the water-electrolyte balance.
• Decrease in diuresis down to complete absence of urine (oliguria and anuria).
• Gastric and intestinal paresis.

Subsequent days (3rd–8th days). At this stage, infectious, inflammatory, and thrombotic processes come to the forefront. There is a risk of developing postoperative pneumonia, suppuration of the surgical wound, thrombophlebitis, and thromboembolism. The probability of progressive cardiovascular dysfunction and the manifestation of acute hepatorenal failure also persists.

Respiratory and circulatory disorders

Respiratory disorders are particularly characteristic of the early postoperative period and are more common in elderly patients.

The main causes of respiratory center depression are anesthetic agents and muscle relaxants that have not been fully eliminated from the body. If the patient has not fully emerged from anesthesia, there is a high risk of vomiting and regurgitation followed by aspiration of vomitus.

The clinical presentation of respiratory impairment includes:

• Hypoventilation (breathing becomes shallow and infrequent).
• Posterior displacement of the tongue, blocking the airways.
• Complete cessation of breathing (apnea).

As emergency care, strict monitoring of the patient is required until they are fully awake. If the tongue falls back, airways must be used immediately. If respiratory arrest or severe respiratory impairment occurs, immediate mechanical ventilation using an Ambu bag is indicated. In case of pronounced drug-induced depression, respiratory analeptics are used (nalorphine, bemegride). Subsequently, bronchitis, pneumonia, or pulmonary atelectasis may develop. Their prevention includes early mobilization, adequate pain management, therapeutic exercises, aerosol inhalations, percussion chest massage, and inflation of rubber chambers to expand collapsed alveoli.

Hemorrhage is considered the most formidable postoperative complication. It can be external (when the dressing is heavily soaked with blood) and internal (hemorrhage occurs into the thoracic or abdominal cavity, as well as into soft tissues). General signs of blood loss include pronounced pallor of the skin, a drop in blood pressure (BP), and tachycardia (frequent but weak pulse). In internal hemorrhage, there is also the release of blood from inserted drains and the increase of specific laboratory signs. Treatment begins with conservative therapy. If it is unsuccessful, emergency wound revision and re-operation (relaparotomy or retoracotomy) are required.

Water-electrolyte imbalance and renal pathologies

Water-electrolyte balance disorders can manifest both in the first days (due to the underlying disease, massive blood loss, or loss of physiological fluids) and in the late period (e.g., during the formation of intestinal fistulas).

Clinical signs of dehydration and electrolyte imbalance are quite specific:

• Pronounced dryness of the skin and tongue.
• Increase in skin temperature against the background of a decrease in its turgor.
• Severe, uncontrolled thirst.
• Palpatory softness of the eyeballs.
• Decrease in central venous pressure (CVP) and hematocrit level.
• Decrease in urine output volume (oliguria).
• Rapid heartbeat (tachycardia).

Correction of the developed deficit is carried out by transfusion of Ringer-Locke solutions, potassium chloride, and combined preparations ("Sodium acetate + Sodium chloride"). In the late period, constant drug correction and transfer of the patient to parenteral nutrition are required. Therapy is carried out under strict control of CVP, diuresis, and blood electrolyte levels.

Urination disorders may be associated with changes in the excretory function of the kidneys, routine urinary retention, or the addition of inflammatory processes (cystitis, urethritis, pyelonephritis).

Intestinal paresis and cardiac complications

After surgical interventions on the gastrointestinal tract, dynamic intestinal obstruction (intestinal paresis) naturally develops within the first 2–3 days. Clinically, this manifests as pronounced abdominal distension and the complete absence of normal peristaltic sounds. The following are used for the treatment and prevention of paresis:

• Gastric and intestinal intubation.
• Mandatory early mobilization of the patient.
• High-quality pain management, including epidural anesthesia methods.
• Paranephric blocks.
• Use of intestinal motility stimulants (e.g., neostigmine methylsulfate) and didynamic currents.

Complications from the cardiovascular system often occur in elderly patients, as well as against the background of uncompensated blood loss and electrolyte disturbances. The main manifestation is acute cardiovascular failure accompanied by rhythm disorders and tachycardia. With the development of left ventricular failure and pulmonary edema, CVP rises sharply. In this case, individual selection of cardiac glycosides, antiarrhythmic, and coronary vasodilator drugs is required. If the patient develops pulmonary edema, ganglionic blockers and diuretics are used emergently, and inhalation of alcohol-moistened oxygen is prescribed.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Technique of relaparotomy and retoracotomy for hemorrhages
• Pharmacological action of respiratory analeptics (nalorphine, bemegride)
• Mechanism of development of dynamic intestinal obstruction
• Features of the use of cardiac glycosides in the postoperative period
• Technique of paranephric block for intestinal stimulation

Other topics in "CHAPTER 8. SURGICAL OPERATION"

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