SU28.3 | Peritonitis — Summary & Reflection

KEY TAKEAWAYS

Peritonitis is inflammation of the peritoneum, recognised clinically by the patient who lies still with a tender, guarded, rigid abdomen and rebound tenderness, absent bowel sounds and features of systemic sepsis. It is classified into primary (spontaneous bacterial peritonitis, SBP — no surgical source, monomicrobial, classically in cirrhotic ascites, treated with antibiotics alone), secondary (the common surgical type from perforation/ischaemia/leak of a viscus, polymicrobial, needing source control) and tertiary (persistent/recurrent in the critically ill); and into localised vs generalised. Common causes are perforated peptic ulcer, appendix, typhoid ileal perforation and diverticular disease. Investigations include bloods, an erect chest X-ray for free gas under the diaphragm, USG/CT, and an ascitic tap (PMN >=250/mm3 confirms SBP). Complications are septic shock, paralytic ileus, intra-abdominal abscess and multi-organ failure. Management of secondary peritonitis rests on three parallel pillars — resuscitation, broad-spectrum antibiotics and source control — with source control being decisive; SBP is the antibiotic-only exception.

REFLECT

Picture the next patient you will see with severe abdominal pain. Would you recognise the difference between the patient who lies dead still with a rigid abdomen and the one who writhes with colic, and would you act on it? Reflect on the first hour: could you confidently start large-volume fluids, pass a nasogastric tube and catheter, take cultures and start antibiotics, and arrange an erect chest X-ray and an urgent surgical review — all in parallel — rather than waiting for one test before doing the next? And consider the trap in reverse: faced with a deteriorating cirrhotic patient with ascites, would you remember to tap the fluid and look for spontaneous bacterial peritonitis before reaching for the operating theatre? Choose one part of this resuscitation sequence you will rehearse until it is automatic.