Effect of Timing of Mechanical Chest Compression Device Applied on Adrenaline Time: A Single-Center Prospective...

 The relationship between the timing of mechanical chest compression device (MCD) application and adrenaline administration in out-of-hospital cardiac arrest (OHCA) remains unclear. This study aimed to examine the association between the time from patient contact to MCD chest compression initiation (MCD time) and that from patient contact to adrenaline administration (adrenaline time) in OHCA, in order to assess whether early MCD application facilitates early adrenaline administration.

 This single-center prospective cohort study used emergency transport data from the Yokosuka City Fire Bureau. Cases where adrenaline was administered by emergency life-saving technicians after MCD application in prehospital settings were included. Patients were categorized into the early (1-5 min) and late (≥ 6 min) MCD groups based on the median MCD time. The primary outcome was adrenaline time, and the secondary outcome was scene time interval (STI), defined as the time from patient contact to departure from the scene. Based on a median STI of 16 min, cases were categorized into short (1-16 min) and long (≥ 17 min) groups. Multivariable logistic regression analysis was conducted using propensity scores to adjust for confounders.

Overall, 174 patients were analyzed, with 92 (52.9%) and 82 (47.1%) in the early and late MCD groups, respectively. The early MCD group had a significantly shorter median adrenaline time than the late MCD group (14.0 vs. 18.0 min). Early MCD application was significantly associated with earlier adrenaline administration (adjusted odds ratio (AOR): 3.47; 95% confidence interval (CI): 1.61-7.49) but not with reduced STI (AOR: 1.71; 95% CI: 0.80-3.68).

Early MCD application in OHCA was associated with earlier adrenaline administration without extending STI. Regional Medical Control Councils should establish protocols and conduct simulation training to optimize early MCD application and early adrenaline administration.