On the ward, patients on oxygen spent nearly a third of their time above target

The edition in brief

SAVE-O2 AI (JAMA Internal Medicine, 1 October) randomised 300 acutely ill adults on supplemental oxygen at four US hospitals to automated closed-loop titration or usual manual adjustment for 72 hours. Automation raised time within the SpO2 target of 90 to 96% from 63% to 85%, and cut time above 96% from 29% to 9%. A network meta-analysis of 27 trials (Arquivos Brasileiros de Cardiologia, 26 October) found candesartan and telmisartan, but not other ARBs, reduced major cardiovascular events against placebo in people without heart failure, though comparisons between ARBs were mostly indirect. A systematic review (American Journal of Medicine, 4 October) found shingles is associated with a transient rise in stroke risk peaking three to four weeks after onset, strongest after ophthalmic zoster; the link to myocardial infarction is weaker. A benchmark of six commercial large language models on Choosing Wisely scenarios (Annals, 20 October) found overuse concentrated in two places: thyroid ultrasound for small incidental nodules and routine ECGs in low-risk adults. The pearl covers oxygen targets. The edition closes on Canada's Using Labs Wisely collaborative of 157 hospitals: urea, AST and coagulation profiles were the commonest low-value inpatient tests, and multimodal changes to order sets drove most reduction efforts.