Application of focused echocardiographic evaluation in life support (FEEL) in pre-hospital care is feasible, and alters diagnosis and management in a significant number of patients, according to a study in the November issue of Resuscitation.
Emergency echocardiography has been proposed as a basic diagnostic tool for the hemodynamically unstable critically ill patient, for acute severe dyspnea and during cardiopulmonary resuscitation (CPR). Furthermore, early echocardiography is now recommended in guidelines relating to the diagnosis of suspected pulmonary embolism or pericardial effusion.
The aim is to use FEEL to diagnose or exclude some of the potentially treatable causes of cardiac arrest, including tamponade, massive pulmonary embolism, severe ventricular dysfunction and hypo-volemia, as well as fine ventricular fibrillation missed by surface ECGs, thereby optimizing peri-resuscitation care, according to the study.
"Hence the use of FEEL is to improve resuscitative efforts but not to terminate resuscitation," the authors wrote.
FEEL has been developed to be used by cardiologists and non-cardiologists alike, as an adjunct to resuscitation in an advanced life support (ALS)-compliant manner.
Raoul Breitkreutz, MD, from JohannWolfgang-Goethe University Hospital in Frankfurt am Main, Germany, and colleagues included 230 patients, with 204 undergoing a FEEL exam during ongoing cardiac arrest (100) and in a shock state (104).
Peri-resuscitation echocardiography was implemented during an ALS-conformed interruption of CPR of fewer than 10 seconds. Echocardiographic findings were documented from images taken from one of three standard echocardiography views (subcostal, parasternal or apical). Features noted were cardiac motion (present or absent), ventricular function (normal, moderately impaired, severely impaired or absent), right ventricular dilatation or peri-cardial collection.
They obtained images of diagnostic quality in 96 percent of cases. In 35 percent of those with an ECG diagnosis of asystole, and 58 percent of those with pulseless electrical activity (PEA), coordinated cardiac motion was detected, and associated with increased survival. Echocardiographic findings altered management in 78 percent of cases.
The researchers suggested that echocardiography in the peri-resuscitation setting "may have a further role in determining whether the patient has 'pseudo-PEA' (coordinated electrical activity, no palpable pulse, but with coordinated cardiac activity) or 'true-PEA' (electrical activity but no detectable cardiac motion and no palpable pulse.
"The latter could now with accuracy be labeled electromechanical dissociation and the former PEA," they concluded. "The findings of this study call into question some of the peri-arrest diagnoses that are made, and demonstrate that echocardiography can be used in the pre-hospital setting to diagnose many of the potentially reversible causes of cardiac arrest, not identifiable by any other means."