Seven new papers today — here are the top four. Paper one — impedance threshold devices linked to better prehospital ROSC but worse survival to discharge. Paper two — the first Aus-ROC report on paediatric cardiac arrest in Australia and New Zealand. Paper three — unwitnessed arrests are most consistently linked to female sex and arrest at home. Paper four — redirecting non-urgent ED patients to primary care looks safe.

Paper one — Resuscitation. A retrospective analysis of a national United States EMS registry, ninety-seven thousand four hundred and thirty-nine adults with non-traumatic out-of-hospital cardiac arrest. The question: does an impedance threshold device change outcomes? Patients treated with the device alone had higher rates of return of spontaneous circulation — twenty-six point seven per cent versus twenty-three point eight. But survival to hospital discharge was lower — twenty-three point nine per cent versus thirty-two per cent — and neurological outcomes were worse too. Adding active compression-decompression pushed both trends further. The number that jumps out at me is that gap between early and late outcomes — more hearts restarted, fewer patients leaving hospital. Caveats: device use wasn't randomised, and disposition outcomes were only available for about a quarter of patients. Worth watching rather than acting on — and impedance threshold devices aren't in standard kit across Australian services anyway.

Paper two — also Resuscitation. The Australasian Resuscitation Outcomes Consortium has published the first epidemiology report on paediatric out-of-hospital cardiac arrest across Australia and New Zealand, drawn from the Epistry registry. The abstract isn't out yet, so there are no numbers to quote — but this is our own population data, and paediatric arrest is rare enough that Australasian figures have been thin on the ground. One for the dashboard, with the detail to follow.

Paper three — Heart and Lung. A systematic review of twenty-two studies covering two hundred and ten thousand and twenty-eight people, asking what predicts an unwitnessed cardiac arrest. Two factors came out most consistently: female sex, and arrest at home. Weaker, mostly unadjusted evidence pointed to arrests at night or during sleep, low socioeconomic status, type one diabetes and psychiatric illness. Unwitnessed arrests have survival rates below five per cent, so recognising who's at risk of being found late matters for community awareness and bystander CPR campaigns. The caveat: much of the underlying evidence was unadjusted, and definitions of witnessed status varied between studies.

Paper four — Emergency Medicine Australasia. A scoping review of nine studies — eight observational, one randomised trial — on redirecting non-urgent emergency department patients to primary care. The safety numbers hold up: a nine point seven per cent return rate, one point seven per cent hospitalisation, and mortality of just zero point zero seven per cent. The programs reporting zero hospitalisations and deaths shared the richest set of safeguards — structured triage, vital signs, documentation of chief complaints and patient registration. As Australian ambulance services expand referral and alternate-pathway models, this is reassuring background — though the studies were mostly observational with varied models and short follow-up.

Quick recap. One — impedance threshold devices: better prehospital ROSC, worse survival to discharge. Two — the first Aus-ROC report on paediatric cardiac arrest in Australia and New Zealand. Three — unwitnessed arrests are most consistently linked to female sex and home location. Four — redirecting non-urgent patients to primary care looks safe.

Also on the dashboard today — paramedic confidence in neonatal and paediatric mental health, building a prehospital suicidal-ideation policy, and priority transport in multi-patient crashes.

That's the roundup for Saturday the tenth of October. Back tomorrow.