Master Surgery & Allied
for PMDC NLE Step 1

What the PMDC NLE Step 1 Tests in Surgery & Allied

The PMDC NLE Step 1 Surgery & Allied section tests clinical decision-making for common surgical presentations: acute abdomen, trauma, burns, hernias, breast lumps, thyroid nodules, and colorectal emergencies. Candidates must differentiate surgical from medical causes, apply the ABCDE approach in trauma, recognise indications for emergency surgery (e.g., perforated viscus, strangulated hernia, acute limb ischaemia), and recall specific scoring systems (e.g., Alvarado for appendicitis, Ranson’s for pancreatitis, Glasgow-Blatchford for upper GI bleed). Knowledge of perioperative care, wound classification (clean/contaminated/dirty), antibiotic prophylaxis timing (within 60 minutes pre-incision), and fluid resuscitation (Parkland formula for burns) is essential. The exam emphasises management algorithms, not rare pathology.

High-Yield Concepts

• Acute Appendicitis – Alvarado Score: Score ≥7 indicates high probability; components: migration of pain (1), anorexia/acetone (1), nausea/vomiting (1), tenderness in RLQ (2), rebound pain (1), fever >37.3°C (1), leukocytosis >10,000 (2). First-line: appendicectomy (open or laparoscopic); antibiotics alone (e.g., co-amoxiclav) only in uncomplicated cases with no faecolith.
• Burns – Parkland Formula: Total fluid in first 24 hours = 4 ml × body weight (kg) × %TBSA (second/third degree). Half given in first 8 hours from time of burn, remainder over next 16 hours. Use Ringer’s lactate. Urine output target: 0.5–1 ml/kg/hour in adults. Do not include first-degree burns in %TBSA.
• Hernias – Strangulation vs Incarceration: Incarcerated hernia: irreducible but no vascular compromise. Strangulated: irreducible + pain + tenderness + signs of obstruction (vomiting, distension) ± gangrene. Emergency surgery required for strangulation; attempt reduction for incarcerated if no peritonitis. Richter’s hernia: only part of bowel wall strangulated, may present without obstruction.
• Breast Lumps – Triple Assessment: Clinical examination, imaging (ultrasound for <35 years, mammogram for ≥35), and core needle biopsy. BIRADS classification: 4 or 5 requires biopsy. First-line for early breast cancer: wide local excision + sentinel lymph node biopsy + radiotherapy (if ER+, add tamoxifen or aromatase inhibitor).
• Acute Pancreatitis – Ranson’s Criteria: At admission: age >55, WBC >16,000, glucose >11 mmol/L, LDH >350 IU/L, AST >250 IU/L. At 48 hours: haematocrit drop >10%, BUN rise >1.8 mmol/L, calcium <2.0 mmol/L, PaO2 <60 mmHg, base deficit >4 mEq/L, fluid sequestration >6 L. ≥3 indicates severe pancreatitis; CT with contrast if severe.
• Upper GI Bleed – Glasgow-Blatchford Score: Score 0: low risk, discharge possible. Components: BUN (mmol/L), Hb (g/L), systolic BP, pulse, melaena, syncope, hepatic disease, cardiac failure. First-line: IV PPI (omeprazole 80 mg bolus then 8 mg/hour), urgent endoscopy within 24 hours for high risk. Variceal bleed: terlipressin + prophylactic antibiotics (ceftriaxone).
• Trauma – ATLS Primary Survey: ABCDE: Airway with C-spine control, Breathing (tension pneumothorax: needle decompression second intercostal space midclavicular line), Circulation (IV access ×2, bolus 1 L crystalloid; if no response, consider haemorrhagic shock and massive transfusion protocol 1:1:1 PRBC:FFP:platelets), Disability (GCS), Exposure. eFAST for haemoperitoneum/pericardial effusion.
• Colorectal – Diverticulitis Management: Uncomplicated (Hinchey Ia): oral antibiotics (metronidazole + ciprofloxacin) and bowel rest. Complicated (abscess >4 cm, perforation, fistula): IV antibiotics, percutaneous drainage if abscess, or Hartmann’s procedure for purulent/faecal peritonitis. Avoid colonoscopy during acute episode.

Common Traps in Surgery & Allied Questions

• Confusing Ranson’s criteria with Glasgow-Imrie criteria for pancreatitis; both exist but Ranson’s is more common in US/PMDC context.
• Applying Parkland formula to first-degree burns – only second and third degree count.
• Assuming all incarcerated hernias need emergency surgery – only strangulated or irreducible with obstruction require immediate operation.
• Using morphine in acute abdomen before surgical review – may mask peritonitis signs; use small doses if needed.
• Forgetting to check pregnancy test in women of childbearing age with RLQ pain – ectopic pregnancy can mimic appendicitis.
• Prescribing antibiotics for simple haemorrhoids – no indication unless thrombosed or infected.

How to Revise Surgery & Allied for the PMDC NLE Step 1

Prioritise acute surgical presentations (appendicitis, cholecystitis, pancreatitis, bowel obstruction, trauma) and their scoring systems. Questions often present a clinical vignette with vitals, labs, and imaging findings; you must decide next step (e.g., CT vs surgery vs observation). Memorise cut-offs: Alvarado ≥7, Ranson ≥3, Parkland formula, Glasgow-Blatchford 0. Practise distinguishing surgical from medical jaundice (obstructive: dilated ducts, raised ALP/GGT) and acute limb ischaemia (6 Ps: pain, pallor, pulselessness, paraesthesia, paralysis, poikilothermia). Review ATLS protocols for trauma, especially tension pneumothorax and haemorrhagic shock. Do not neglect basic perioperative care: wound classification, antibiotic prophylaxis, DVT prophylaxis (LMWH). Focus on common, not rare, conditions.

Practise it: MedLumen has 50 Surgery & Allied questions for the PMDC NLE Step 1, each with a full explanation and references.