Enumerate the principles of management of peritonitis.

Principles of Management of Peritonitis

The management of peritonitis is an emergency and requires a systematic, multidisciplinary approach. The core principles can be broadly categorized into immediate resuscitation and stabilization, definitive source control, targeted antimicrobial therapy, and intensive supportive care.

1. Immediate Resuscitation and Stabilization

The initial phase of management focuses on stabilizing the patient and correcting life-threatening physiological derangements caused by sepsis and fluid shifts.

• Fluid Resuscitation: Aggressive intravenous fluid therapy is crucial to combat hypovolemia resulting from fluid sequestration into the peritoneal cavity and systemic vasodilation due to sepsis. Crystalloids are typically preferred.
• Electrolyte Correction: Peritonitis can lead to significant electrolyte imbalances. Regular monitoring and correction of electrolytes (e.g., sodium, potassium, calcium) are essential.
• Hemodynamic Monitoring: Close monitoring of vital signs (heart rate, blood pressure, respiratory rate), urine output, central venous pressure (CVP), and arterial blood gas analysis is critical to guide fluid therapy and assess organ perfusion.
• Oxygen Supplementation: Patients with peritonitis often develop respiratory compromise. Supplemental oxygen should be provided to maintain adequate tissue oxygenation.
• Analgesia: Adequate pain management is important for patient comfort and to reduce stress responses, though care must be taken not to mask critical clinical signs.
• Gastric Decompression: Insertion of a nasogastric tube helps to decompress the stomach, reduce vomiting, prevent aspiration, and minimize further peritoneal contamination in cases of gastrointestinal perforation.

2. Definitive Source Control

This is the cornerstone of peritonitis management, aiming to eliminate the cause of peritoneal contamination.

• Surgical Intervention: For most cases of secondary peritonitis (e.g., due to perforated appendix, diverticulitis, peptic ulcer, or trauma), emergency surgery is mandatory. The goals of surgery include:
  • Repairing any perforations or leaks in the gastrointestinal tract.
  • Resecting necrotic or severely damaged tissue (e.g., gangrenous bowel).
  • Draining any localized abscesses or purulent collections.
  • Thorough peritoneal lavage to remove pus, fibrin, and contaminants, though its routine benefit is debated in certain contexts.
• Non-operative Drainage: In some localized collections or abscesses, percutaneous drainage guided by ultrasound or CT scan may be an alternative to surgery, especially in stable patients without generalized peritonitis.

3. Targeted Antimicrobial Therapy

Antibiotics play a vital role in controlling infection, both locally and systemically.

• Empiric Broad-Spectrum Antibiotics: Administration of broad-spectrum antibiotics should begin immediately after diagnosis, even before culture results are available. The choice of antibiotics should cover common pathogens found in abdominal infections, typically gram-negative bacilli and anaerobes (e.g., metronidazole, third-generation cephalosporins, carbapenems).
• Culture-Guided Therapy: Once culture and sensitivity results are available from peritoneal fluid or blood, antibiotic therapy should be de-escalated and tailored to the specific microorganisms identified.
• Duration of Therapy: The duration of antibiotic therapy depends on the severity of infection, the effectiveness of source control, and the patient's clinical response.
• Antifungal Prophylaxis: In certain high-risk patients or those with specific risk factors, antifungal agents may be considered.

4. Intensive Supportive Care

Ongoing care is essential to support organ function and prevent complications.

• Nutritional Support: Early nutritional support, ideally enteral (via nasogastric or jejunal tube) or parenteral (intravenous), is crucial to maintain gut integrity, support immune function, and prevent malnutrition in critically ill patients.
• Prophylaxis for Complications:
  • Deep Vein Thrombosis (DVT) Prophylaxis: Heparin or low-molecular-weight heparin is used to prevent blood clots.
  • Stress Ulcer Prophylaxis: Proton pump inhibitors (PPIs) or H2 blockers are given to prevent gastric stress ulcers.
• Monitoring for Abdominal Compartment Syndrome (ACS): Elevated intra-abdominal pressure is a serious complication, particularly in severe peritonitis. Regular monitoring of intra-abdominal pressure (e.g., via bladder pressure measurement) and appropriate interventions (e.g., decompressive laparotomy) may be required.
• Intensive Care Unit (ICU) Management: Patients with severe peritonitis, sepsis, or septic shock often require admission to an ICU for continuous monitoring, ventilatory support, vasopressors, and advanced organ support.
• Management of Organ Dysfunction: Specific interventions for renal failure (dialysis), respiratory failure (mechanical ventilation), or other organ dysfunctions must be initiated promptly.

The success of peritonitis management relies on early recognition, rapid initiation of resuscitation, timely and effective source control, appropriate antimicrobial use, and comprehensive supportive care. Adherence to established guidelines, such as those from the International Society for Peritoneal Dialysis (ISPD) for dialysis-associated peritonitis, is vital to improve patient outcomes.

Type of Peritonitis	Primary Cause/Mechanism	Key Management Principle
Primary (Spontaneous Bacterial Peritonitis - SBP)	Bacterial translocation, often in patients with liver cirrhosis and ascites, without an evident intra-abdominal source.	Empiric broad-spectrum antibiotics (e.g., third-generation cephalosporins), often followed by culture-guided therapy. Surgical intervention is usually NOT required.
Secondary Peritonitis	Perforation or leakage from an intra-abdominal organ (e.g., ruptured appendix, diverticulitis, perforated ulcer, trauma).	Emergency surgical source control (repair, resection, drainage) combined with broad-spectrum antibiotics and supportive care.
Tertiary Peritonitis	Persistent or recurrent peritonitis after initial surgical and antibiotic treatment, often due to immunocompromise or resistant organisms.	Aggressive re-evaluation for missed source, repeat surgical exploration, advanced microbiology (fungal, resistant bacteria), and prolonged intensive care.
Peritoneal Dialysis-Associated Peritonitis	Contamination of the peritoneal catheter in patients undergoing peritoneal dialysis.	Intraperitoneal antibiotics (empiric, then targeted), meticulous catheter care, and in some cases, catheter removal.