# CALL TO ECLS—Acronym for Reporting Patients for Extracorporeal Cardiopulmonary Resuscitation Procedure from Prehospital Setting to Destination Centers

## TL;DR

The acronym CALL TO ECLS is evaluated as a communication tool for qualifying patients for ECPR, and it is found to be accurate and useful for prehospital communication.

## Contribution

The study validates the CALL TO ECLS acronym as a reliable and clear communication tool for ECPR patient qualification.

## Key findings

- The acronym CALL TO ECLS was rated as highly valid and useful by experts.
- All criteria in the acronym were deemed significant and important for ECPR patient qualification.
- A revised version of the acronym was developed based on expert feedback.

## Abstract

The acronym CALL TO ECLS has been proposed as a potential tool to support decision-making in critical communication moments when qualifying a patient for the ECPR procedure. The aim of this study is to assess the accuracy of the acronym and validate its content. Validation is crucial to ensure that the acronym is theoretically correct and includes the necessary information that must be conveyed by EMS during the qualification of a patient with out-of-hospital cardiac arrest for ECMO. A survey was conducted using the LimeSurvey platform through the Survey Research System of the Jagiellonian University Medical College over a 6-month period (from December 2022 to May 2023). Usefulness, importance, clarity, and unambiguity were rated on a 4-point Likert scale, from 1 (not useful, not important, unclear, ambiguous) to 4 (useful, important, clear, unambiguous). On the 4-point scale, the Content Validity Index (I-CVI) was calculated as the percentage of subject matter experts who rated the criterion as having a level of importance/clarity/validity/uniqueness of 3 or 4. The Scale-level Content Validity Index (S-CVI) based on the average method was computed as the average of I-CVI scores (S-CVI-AVE) for all considered criteria (protocol). The number of fully completed surveys by experts was 35, and partial completion was obtained in 63 cases. All criteria were deemed significant/useful, with I-CVI coefficients ranging from 0.87 to 0.97. Similarly, the importance of all criteria was confirmed, as all I-CVI coefficients were greater than 0.78 (ranging from 0.83 to 0.97). The average I-CVI score for the ten considered criteria in terms of usefulness/significance and importance exceeded 0.9, indicating high validity of the tool/protocol/acronym. Based on the survey results and analysis of responses provided by experts, a second version was created, incorporating additional explanations. In Criterion 10, an explanation was added—“Signs of life”—during conventional cardiopulmonary resuscitation (ROSC, motor response during CPR). It has been shown that the acronym CALL TO ECLS, according to experts, is accurate and contains the necessary content, and can serve as a system to facilitate communication between the pre-hospital environment and specialized units responsible for qualifying patients for the ECPR.