General Surgery: Acute Abdomen, Trauma and Hernia Emergencies
General Surgery accounts for the largest share of the Part 1 MCQ. The exam tests applied basic science and safe early management: recognition of the acute abdomen, trauma priorities, hernia complications, and hepatobiliary and colorectal emergencies.
Core rules
- Trauma: follow the ATLS sequence; catastrophic haemorrhage and tension pneumothorax are treated before detailed airway assessment. Shock in trauma is haemorrhagic until proven otherwise.
- Peritonitis: generalised rigidity and rebound tenderness imply surgical pathology; a single normal white cell count does not exclude it.
- Bowel obstruction: plain abdominal X-ray shows dilated loops and air-fluid levels, but CT defines the transition point and detects strangulation. Red flags are constant pain, tachycardia, fever, localised tenderness, raised lactate and a closed-loop pattern.
- Hernia: irreducible, tender and obstructive symptoms indicate incarceration; systemic toxicity or skin change indicates strangulation, which requires emergency operation rather than taxis.
- Hepatobiliary: right upper quadrant pain, fever and jaundice form Charcot triad (cholangitis); hypotension and confusion complete Reynolds pentad. Biliary sepsis needs antibiotics and drainage, usually by ERCP.
- Colorectal: diverticulitis is confirmed by CT; the Hinchey classification guides percutaneous versus operative drainage.
Worked example
A 68-year-old man has 24 hours of colicky central abdominal pain, vomiting and absolute constipation. He had an appendicectomy 30 years ago. Pulse is 105/min, BP 100/60 mmHg, temperature 38.1°C; the abdomen is distended and tender in the right lower quadrant. Abdominal X-ray shows multiple air-fluid levels, and CT shows dilated small bowel with a transition point and a closed loop.
Reasoning: the history is small bowel obstruction, most likely adhesive. Tachycardia, fever, localised tenderness and a closed-loop pattern are red flags for ischaemia. Management is resuscitation, nasogastric decompression, intravenous fluids with potassium, analgesia and urgent laparotomy, not a trial of conservative therapy. CT is preferred because it excludes strangulation and plans the incision.
Traps
- Murphy sign is useful but insensitive; ultrasound is the test of choice for acute cholecystitis.
- Ranson criteria are scored over 48 hours, not at admission.
- A normal amylase does not exclude pancreatitis.
- In pregnancy, appendicitis often causes pain higher than the right iliac fossa; MRI is preferred when ultrasound is non-diagnostic.