ABSTRACT
Pre-cordial thump (PT) relies on cardiac mechano-electric transduction to transform mechanically-delivered energy into an electrophysiologically relevant stimulus. Its use for emergency resuscitation has declined recent years, amidst concerns about effectiveness and side-effects. In addition, there is insufficient knowledge about bio-mechanical properties and mechanisms of PT. Using a PT-mechanics recorder, we measured PT off-patient among healthcare professionals (n = 58) in North-East Italy, and related this to retrospective information on self-reported PT outcomes. Impact-speed and peak-force were 4.7 ± 1.3 m s⻹ (2.2-7.8 m s⻹) and 394 ± 110 N (202-648 N), respectively. Average self-reported cardioversion rate by PT was 35%. No adverse events were stated. All but 3 of PT providers with self-reported cardioversion rates ≥50% had pre-impact fist-speeds of ≥3.7 m s⻹. In comparison with previously-reported data from UK and US (n = 22 each), self-reported success-rates and pre-impact fist-speeds were more similar to US (PT-induced cardioversion rate 27.7%; fist-speed 4.17 ± 1.68 m s⻹) than to UK participants (PT-induced cardioversion rate 13.3%; fist-speed 1.55 ± 0.68 m s⻹). Small cohort-size, retrospective nature of data-gathering, and 'self-selection bias' (participants who have used PT on patients) limits the extent to which firm conclusions can be drawn. Observations are compatible, though, with the possibility that pre-impact fist-speed may affect success-rate of PT. Thus, where PT is used for acute resuscitation, it is delivered because it is immediately 'at hand'. Negative side effects are rare or absent in witnessed cardiac arrest cases. Pre-impact fist-speed may be a determinant of outcome, and this could be trained using devices suitable for self-assessment.
