A dexmedetomidine recall, and the weight you should be dosing remimazolam against

The edition in brief

The FDA has classified a recall of Baxter's dexmedetomidine hydrochloride in 0.9% sodium chloride, 400 micrograms per 100 mL in the Galaxy single-dose container, as Class II, for current good manufacturing practice deviations; the recall is recorded as ongoing. Class II means a reasonable probability of temporary or medically reversible harm, and the reason is a process deviation rather than an identified patient injury — but premixed bags are what most units reach for, and the practical problem is supply and substitution rather than toxicity. A population pharmacokinetic study in 44 volunteers, 30 of them with obstructive sleep apnoea, found remimazolam clearance high at 1.09 L/min and strongly dependent on total body weight, with no independent effect of obstructive sleep apnoea severity on drug disposition. Context-sensitive half-time after a four-hour infusion was 4.02 minutes in class 2 and 3 obesity. Dosing on lean or ideal body weight at induction and adjusted body weight for maintenance reproduced the profile seen with total body weight dosing in normal-weight patients. In 31 patients on chronic intrathecal bupivacaine for cancer pain, a mean daily dose of 39.5 mg produced a mean serum concentration of 167.7 micrograms per litre against a toxicity threshold of 2000 — reassuring, though the standard deviation of 266.2 shows a wide spread, and higher infusion flow rate remained independently associated with higher serum levels after adjusting for dose. A randomised trial of esketamine at induction and in patient-controlled analgesia after laparoscopic colorectal resection reported lower anxiety and depression scores on days 1 and 3, but published no effect sizes.