Use of Transthoracic Impedance Data to Evaluate Intra-arrest Chest Compression Quality

Jonathan W Kamrud

doi:10.23937/2474-3674/1510014

Abstract

Mechanical compression devices purportedly improve the quality of chest compressions by minimizing interruptions and maintaining optimal rate and depth, but this claim has not been objectively substantiated using transthoracic impedance (TTI) recordings from applied setting cardiac arrests. In this study, we use TTI data to compare chest compression quality metrics from the manual versus mechanical compression phases of out-of-hospital cardiac arrests (OHCA) treated with the LUCAS mechanical compression device.

Highlights

An estimated 350,000 people suffer out-of-hospital cardiac arrests (OHCA) annually in the United States
According to the most recent cardiopulmonary resuscitation (CPR) guidelines from the American Heart Association (AHA), an essential component of high quality CPR is the delivery of chest compressions at the proper rate and depth with minimal interruption [2], and transthoracic impedance (TTI) data captured by electrocardiogram (EKG) defibrillator/monitors can be used to retrospectively assess certain aspects of chest compression quality [3]
149 incidents were excluded from analysis because the mechanical compression device was not used (n = 4) or was placed prior to ambulance arrival (n = 65), TTI data were of poor quality (n = 25) or unavailable (n = 36), or the patient received < 5 minutes of compressions in the presence of ambulance personnel (n = 19)

Summary

Introduction

An estimated 350,000 people suffer out-of-hospital cardiac arrests (OHCA) annually in the United States. In 2013, only 9.5% of OHCA victims survived to hospital discharge [1], and it is well known that a key determinant of survival is the rapid delivery of high quality cardiopulmonary resuscitation (CPR) [2]. According to the most recent CPR guidelines from the American Heart Association (AHA), an essential component of high quality CPR is the delivery of chest compressions at the proper rate and depth with minimal interruption [2], and transthoracic impedance (TTI) data captured by electrocardiogram (EKG) defibrillator/monitors can be used to retrospectively assess certain aspects of chest compression quality [3]. In late 2012, we acquired the necessary tools and training to institute a cardiac arrest post-event TTI review process in our ambulance service. Routine use of a mechanical compression device, coupled with the practice of conducting post-arrest TTI data reviews in our system provides a unique opportunity to explore CPR quality under

Methods

Results

Discussion

Conclusion