The ATLS classification of haemorrhagic shock divides blood loss into four classes. A 70 kg patient with Class III haemorrhage would show approximate blood loss of:
- A 750–1,500 mL
- B 1,400–2,000 mL ✓
- C >2,000 mL
- D <750 mL
Correct answer: B. 1,400–2,000 mL
Explanation
ATLS haemorrhagic shock classes (based on percentage of circulating blood volume, approximately 70 mL/kg in adults): Class I <15% (<750 mL); Class II 15–30% (750–1,500 mL); Class III 30–40% (1,500–2,000 mL); Class IV >40% (>2,000 mL). Class III is marked by significant tachycardia (>120 bpm), tachypnoea (30–40 breaths/min), decreased pulse pressure, altered mental status, and decreased urine output requiring blood product transfusion. For a 70 kg patient with ~5L total blood volume, 30–40% = 1,500–2,000 mL.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.