Search

Introduction: Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) improves bystander CPR rates and survival outcomes. This study aimed to identify barriers to successful DA-CPR in patients with out-of-hospital cardiac arrest (OHCA). Methods: This retrospective observational study used data from a nationwide OHCA database from 2017 to 2021. Adult emergency medical services (EMS)-treated patients with OHCA with a presumed cardiac etiology were enrolled. The main exposure variable was compliance with DA-CPR. The primary outcome was good neurological recovery at hospital discharge. Multivariable logistic regression analysis was conducted to identify the major factors associated with unsuccessful DA-CPR with and without multiple imputations. Causal mediation analysis was conducted using witnessed status as a mediator. Results: In the final analysis, 49,165 patients with OHCA were included. A total of 36,865 (75.0%) patients successfully underwent DA-CPR. A higher proportion of good neurological recovery was observed in the successful DA-CPR group than in the non-successful DA-CPR group (P 65 years, male sex, OHCA occurring in a non-metropolitan area or private place, unwitnessed status, whether the bystander was a non-family member or non-cohabitant, female sex or had not received CPR training, and primary call dispatchers not receiving any first-aid training. Additional analyses after multiple imputations showed similar results. Mediation effect was significant for most risk factors for unsuccessful DA-CPR. Conclusions: Bystander characteristics (non-family member or non-cohabitant, female, and uneducated status for CPR) and primary call dispatchers not receiving first-aid training were identified as risk factors for unsuccessful DA-CPR.

Objectives Given that cardiopulmonary resuscitation (CPR) is an aerosol-generating procedure, it is necessary to use a mechanical ventilator and reduce the number of providers involved in resuscitation for in-hospital cardiac arrest in coronavirus disease (COVID-19) patients or suspected COVID-19 patients. However, no study assessed the effect of changes in inspiratory time on flowrate and airway pressure during CPR. We herein aimed to determine changes in these parameters during CPR and identify appropriate ventilator management for adults during CPR. Methods We measured changes in tidal volume (Vt), peak inspiratory flow rate (PIFR), peak airway pressure (Ppeak), mean airway pressure (Pmean) according to changes in inspiratory time (0.75 s, 1.0 s and 1.5 s) with or without CPR. Vt of 500 mL was supplied (flowrate: 10 times/min) using a mechanical ventilator. Chest compressions were maintained at constant compression depth (53 ± 2 mm) and speed (102 ± 2/min) using a mechanical chest compression device. Results Median levels of respiratory physiological parameters during CPR were significantly different according to the inspiratory time (0.75 s vs. 1.5 s): PIFR (80.8 [73.3 – 87.325] vs. 70.5 [67 – 72.4] L/min, P < 0.001), Ppeak (54 [48 – 59] vs. 47 [45 – 49] cmH2O, P < 0.001), and Pmean (3.9 [3.6 – 4.1] vs. 5.7 [5.6 – 5.8] cmH2O, P < 0.001). Conclusions Changes in PIFR, Ppeak, and Pmean were associated with inspiratory time. PIFR and Ppeak values tended to decrease with increase in inspiratory time, while Pmean showed a contrasting trend. Increased inspiratory time in low-compliance cardiac arrest patients will help in reducing lung injury during adult CPR.