Hemodynamic effects of TEE-guided adjustment of the area of the maximal compressions during cardiopulmonary resuscitation.

Abstract

Real-time evidence on left ventricular (LV) parameters during cardiopulmonary resuscitation (CPR), especially before and after adjusting the area of maximal compression (AMC), is limited. This study used three-dimensional transesophageal echocardiography (3D-TEE) to assess LV parameters during resuscitation with and without AMC adjustment. Adult patients with non-traumatic out-of-hospital cardiac arrest (OHCA) were prospectively enrolled. The AMC was identified by two-dimensional (2D)-TEE and LV end-diastolic volume (EDV), and end-systolic volume (ESV) were measured by 3D-TEE to derive stroke volume (SV) and ejection fraction (EF). If AMC aligned with the LV (AMC-LV group), chest compressions were continued; otherwise, the site was adjusted (AMC-non-LV group) for optimal LV alignment and measurements repeated. End-tidal carbon dioxide (EtCO₂₎ data were collected at the time of AMC identification and 1 min after AMC adjustment. Nineteen patients were included. The AMC was located over the LV in 4 patients (21%), while 15 patients (79%) required TEE-guided AMC adjustment. In the AMC-non-LV group, SV (9 vs. 28.6 mL, p = 0.004), EF (20.4 vs. 60.8%, p < 0.0001) and EtCO2 (19 vs. 42 mmHg, p < 0.0001) increased significantly post-adjustment, reaching values comparable to the AMC-LV group. ROSC rates did not differ between the AMC-LV and AMC-non-LV groups (75% vs. 53%, p = 0.603). 2D-TEE-guided identification and adjustment of AMC allowed targeted optimization of chest compressions. Approximately 80% of patients required AMC adjustment. 3D-TEE was used to quantify LV parameters. In patients undergoing AMC adjustment, significant improvements in SV and EF were observed, reaching levels comparable to those without adjustment.