ABSTRACT
OBJECTIVE: Researchers have assumed that compressing the point beneath which the left ventricle (LV) diameter is maximum (P_max.LV) would improve cardiopulmonary resuscitation outcomes. Defining the midsternum, the currently recommended location for chest compression, as the reference (xâ¯=â¯0), the lateral deviation (x_max.LV) of personalized P_max.LV has become estimable using posteroanterior chest radiography. The authors investigated whether out-of-hospital cardiac arrest (OHCA) patients, whose x_max.LV was closer to the midsternum and thus had their P_max.LV compressed closer during cardiopulmonary resuscitation, showed better chances of return of spontaneous circulation (ROSC) and survival to discharge. DESIGN: Retrospective, cross-sectional study. SETTING: A university hospital. PARTICIPANTS: Adult OHCA patients with available previous posteroanterior chest radiography. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: For each clinical outcome, multivariable logistic regression was performed, grouping x_max.LV into tertiles and adjusting the variables selected among the core elements of the Utstein template showing possible differences (p > 0.10) in univariate analysis. Odds ratios were presented as OR (95% confidence interval). Among 268 cases (age 64.4 ± 15.8 y, female 89 [33.2%]), 123 (45.9%) achieved ROSC and 40 (14.9%) survival to discharge. Compared with the third tertile of x_max.LV (59 to â¼101 mm), the first (31 to â¼48 mm) and second (48 to â¼59 mm) tertiles, which had a P_max.LV closer to the midsternum, were negatively associated with ROSC (OR 0.502 [0.262-0.960]; pâ¯=â¯0.037 and OR 0.442 [0.233-0.837]; pâ¯=â¯0.012, respectively) and survival to discharge (OR 0.286 [0.080-1.03]; pâ¯=â¯0.055 and OR 0.046 [0.007-0.308]; pâ¯=â¯0.002, respectively). CONCLUSIONS: OHCA patients with a P_max.LV located closer to the midsternum showed worse chances of ROSC and survival to discharge, which challenges the traditional assumption of identifying P_max.LV as the optimum compression point.
