Shock after trauma laparotomy — classify the category, defend the fluids, start the right pressor

Model answer

(A) Hypovolaemic (haemorrhagic) shock — with obstructive and cardiogenic causes still to exclude (3 marks). Four categories share one mismatch — oxygen supply versus demand — and this is the blood-and-fluids compartment: intravascular volume loss from bleeding, treated by fluid replacement with balanced crystalloids and blood.^[1] Cold peripheries, tachycardia, hypotension, oliguria and lactate 4.2 with Hb 82 after laparotomy fit absolute loss, not relative redistribution. Still exclude tamponade/tension physiology (distended veins, muffled sounds, unilateral silence — obstructive shock needs immediate life-saving intervention, never fluids-and-wait) and pump failure before attributing everything to blood loss.^[1]

(B) Fluids as tested challenges, norepinephrine first, blood by ratio (4 marks). Continue balanced crystalloid as reassessed challenges with dynamic responsiveness testing — static preload markers are repeatedly unreliable, fluids often give no benefit, and excess harms lungs and kidneys; use cardiac-output/stroke-volume changes from postural manoeuvres or mini-challenges before each bolus.^[10][15] Do not chase protocolised venous numbers: PRISM individual data (3,723 patients) found EGDT no better than usual care (24.9% versus 25.4%, odds ratio 0.97) with more ICU days and higher costs.^[14] Start norepinephrine early to MAP 65+ rather than dopamine: SOAP II arrhythmia 24.1% versus 12.4% with dopamine, and meta-analysis gives mortality relative risk 0.89 with number needed to treat 9.^[22][23] Transfuse 1:1:1 plasma:platelets:red cells — PROPPR showed no 24-hour mortality difference (12.7% versus 17.0%) but less exsanguination death (9.2% versus 14.6%) with more haemostasis and no extra complications.^[29]

(C) TXA now, and saline if a head injury coexists (3 marks). Give tranexamic acid 1 g over 10 minutes then 1 g over 8 hours immediately — CRASH-2 (20,211 patients) cut all-cause death (14.5% versus 16.0%, relative risk 0.91) and bleeding death (4.9% versus 5.7%).^[30] Timing decides direction: ≤1 hour relative risk 0.68, 1-to-3 hours 0.79, after 3 hours 1.44 harm — at 4 hours post-injury he is outside benefit, so document why TXA is withheld rather than giving it late.^[31] If he also had traumatic brain injury, resuscitate with saline not balanced: BEST-Living TBI deaths 19.1% versus 14.7% (odds ratio 1.424) with ESICM conditionally recommending saline over balanced in TBI.^[18][19]