Saudi Board Orthopedics Part 1 Complete Review Guide 2026–2027

4. Pyloric obstruction with vomiting causes hypochloraemic hypokalaemic metabolic alkalosis.
5. Refeeding syndrome: hypophosphataemia is the hallmark; start at 10 kcal/kg/day or less with thiamine.
6. Anion gap is Na minus (Cl plus HCO3), normally 8 to 12; lactic acidosis is a common cause of a high gap.
7. Cardiogenic shock: low output, high wedge pressure and high SVR (cold and wet).
8. Septic shock: noradrenaline is the first-line vasopressor; vasopressors needed for MAP 65 or more with lactate over 2 despite fluids.
9. Lung-protective ventilation: tidal volume 6 mL/kg predicted body weight with plateau pressure under 30.
10. Berlin criteria: moderate ARDS at PaO2/FiO2 100 to 200 with PEEP of 5 or more.
11. Necrotising fasciitis: urgent radical debridement with broad antibiotics; LRINEC 6 or more is suspicious.
12. Steam sterilisation: 134 °C for about 3 minutes, or 121 °C for 15 minutes.
13. Healing phases: haemostasis, inflammation, proliferation, remodelling; maximum tensile strength is about 80% of normal skin.
14. A keloid extends beyond the original wound margin, unlike a hypertrophic scar.
15. Restrictive transfusion threshold: Hb 70 g/L (target 70 to 90), and 80 in acute coronary syndrome.
16. TACO is the commonest cause of transfusion mortality; TRALI is non-cardiogenic pulmonary oedema within 6 hours.
17. Acute haemolytic reaction: stop the transfusion at once, keep IV access, check patient and unit identity.
18. Warfarin reversal in life-threatening bleeding: PCC plus IV vitamin K; dabigatran: idarucizumab; heparin: protamine.
19. Stop apixaban 48 hours before high-bleed-risk surgery with normal renal function.
20. HIT occurs 5 to 10 days after starting heparin: stop all heparin and start a non-heparin agent such as argatroban.
21. ATLS: tension pneumothorax is treated by needle decompression at the 4th or 5th intercostal space anterior to the midaxillary line, then a chest drain.
22. Beck triad of tamponade: hypotension, raised JVP and muffled heart sounds.
23. Parkland formula for burns: 4 mL × kg × %TBSA, half in the first 8 hours from time of burn.
24. Urine output target in adult trauma resuscitation is 0.5 mL/kg/h, and 1 in children.

Common mistakes in this chapter

• ✕ Hyperkalaemia with ECG changes gets insulin and glucose first. IV calcium gluconate comes first to stabilise the membrane.
• ✕ Chronic hyponatraemia is corrected quickly. Keep it to 8 to 10 mmol/L per 24 h to avoid osmotic demyelination.
• ✕ Day 1 to 2 postoperative fever is blamed on pneumonia or infection. It is usually the benign inflammatory response to surgery.
• ✕ Prophylactic antibiotics are extended after surgery. In clean surgery do not extend beyond the end of the operation (WHO).
• ✕ Hair is shaved with a razor before surgery. Avoid removal or clip only; razors raise SSI.
• ✕ Bridging anticoagulation is given for AF without a mechanical valve. It is generally unnecessary and increases bleeding.
• ✕ DAPT is stopped early after a recent drug-eluting stent for elective surgery. Defer surgery; do not stop DAPT prematurely.
• ✕ Metronidazole is first-line for non-severe C. difficile. Oral vancomycin or fidaxomicin is now first-line.