Serotonin Syndrome & Neuroleptic Malignant Syndrome

Meet the patient

A 40-year-old man arrives on ICU with a temperature of 41.5 degrees C, heart rate 130, blood pressure swinging between 180 over 100 and 80 over 40, and generalized muscle rigidity. His creatine kinase is 18,000, lactate 7.2, INR 2.1. Three diagnoses are in play: he was started on an SSRI two weeks ago and linezolid yesterday, he had a haloperidol depot injection last week, and he had an anaesthetic with sevoflurane and suxamethonium four hours ago for an unrelated procedure.^[1]

The Fellowship candidate must hold four facts simultaneously: the onset discriminates (minutes for MH, hours for serotonin, days for NMS); the neuromuscular sign discriminates (clonus for serotonin, lead-pipe for NMS, masseter for MH, dry for anticholinergic); the antipyretics are useless in all four; and the specific antidote differs.^[1][4][21]

References24ShowHide

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