Evaluation of out-of-hospital cardiac arrest using transesophageal echocardiography in the emergency department

Background: Transesophageal echocardiography (TEE) has been proposed as a modality to assess patients in the setting of cardiac arrest, both during resuscitation care and following return of spontaneous circulation (ROSC). In this study we aimed to assess the feasibility and clinical impact of TEE during the emergency department (ED) evaluation during out-of-hospital cardiac arrest (OHCA).

Materials and methods: We conducted a prospective observational study consisting of a convenience sample of adult patients presenting to the ED of an urban university medical center with non-traumatic OHCA. TEE was performed by emergency physicians following intubation. Images and clinical data were analyzed. TEE was used intra-arrest in order to assist in diagnosis, assess cardiac activity and determine CPR quality by assessing area of maximal compression (AMC), using a 4 view protocol.

Results: A total of 33 OHCA patients were enrolled over a one-year period, 21 patients (64%) presented with ongoing CPR and 12 (36%) presented with ROSC. The 4-view protocol was completed in 100% of the cases, with an average time from ED arrival to TEE of 12 min (min 3 max 30 SD 8.16). Fine ventricular fibrillation (VF) was recognized in 4 (12%) cases thought to be in asystole, leading to defibrillation, and 2 cases of pseudo-PEA were identified. Right ventricular (RV) dilation, was seen in 12 (57%) intraarrest cases. Intra-cardiac thrombus was found in one case, leading to thrombolysis. The AMC was identified over the aortic root or LVOT in 53% of cases. TEE was found to have diagnostic, therapeutic or prognostic clinical impact in 32 of the 33 cases (97%).

Conclusions: TEE is feasible and clinically impactful during OHCA management. Resuscitative TEE may allow for characterization of cardiac activity, including identification of pseudo-PEA and fine VF, determination of reversible pathology, and optimization of CPR quality.