Sedation, Analgesia and Paralysis in the ICU

Meet the patient

A 58-year-old man is intubated for severe ARDS (PaO2 over FiO2 95). He is on propofol 5 mg/kg/h, fentanyl 150 mcg/h, fighting the ventilator with a driving pressure of 22. BP is 88 over 50 on noradrenaline 0.4. CK is 1200, lactate 3.2, pH 7.28, triglycerides 3.5. The registrar asks whether to add a muscle relaxant.^[18][21]

This is the patient where sedation, analgesia and paralysis collide. Three problems demand attention before the paralytic: the propofol dose (5 mg/kg/h — PRIS is associated with infusions above 4 mg/kg/h for more than 48 hours, and his rising CK and lactate fit the metabolic acidosis and rhabdomyolysis of the syndrome), the untreated pain driving the agitation (pain is assessed and treated before any sedative is escalated), and the hypotension — propofol infusion syndrome includes acute refractory bradycardia and cardiovascular failure, so the drug itself may be contributing. Fix those, then decide whether paralysis is genuinely indicated — the 2026 SCCM guideline conditionally recommends NMBAs in ARDS with a PaO2 over FiO2 below 150.^[18][19][21]

References24ShowHide

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