Outcomes Following Impedance Threshold Device Use During Out-of-Hospital Cardiac Arrest

Existing work is equivocal regarding the benefit of impedance threshold device (ITD) use among patients experiencing out-of-hospital cardiac arrest (OHCA). We examined the association of ITD use with prehospital outcomes and longer-term dispositions in a nationally representative sample of OHCA patients.

We included adult, non-traumatic, OHCA scene runs from the 2024 ESO Data Collaborative. We compared patients treated with (a) ITD only; (b) ITD and active compression-decompression device (ITD+ACD); and (c) neither device (no ITD). Prehospital outcomes included return of spontaneous circulation (ROSC) and survival to hospital arrival (SHA); disposition outcomes included survival to hospital discharge and favorable neurologic outcome (i.e., discharge to home). We used multivariate logistic regression to examine the association of treatment group with outcomes, adjusting for demographics and several potential confounders.

We included 97,439 patient records (85.3% no ITD; 13.1% ITD only; 1.6% ITD+ACD). Disposition outcomes were available for 13,026 patients (23.3%). ROSC was higher for patients treated with ITD only (26.7%) than those treated with no ITD (23.8%; aOR=1.09 [1.04, 1.14]); a similar pattern emerged for SHA. Conversely, survival to discharge was lower for patients treated with ITD only (23.9%) than those treated with no ITD (32.0%; aOR=0.68, [.61, .76]); a similar pattern emerged for favorable neurologic outcome. The ITD+ACD group showed more extreme versions of the trends observed for ITD only.

ITD use was associated with improved prehospital outcomes but worsened dispositional outcomes among patients experiencing OHCA, suggesting this device may prove beneficial early in resuscitation of OHCA patients.