Initial capnography values and resuscitation outcomes of patients assisted by basic life support units in first instance; descriptive prospective study

Abstract

Introduction: Understanding the key factors which affect out hospital cardiac arrest (OHCA) outcomes is essential in order to promote patient treatment. The main objective of this research was to describe the correlations between the capnographic values obtained during the first minute of monitoring on cardiopulmonary resuscitation, assisted by basic life-support units, with the results as return of spontaneous circulation (ROSC) and alive hospital admission. The secondary objectives were to describe the sociodemographic characteristics of the patients assisted, and to analyze any correlations between receiving basic life-support units and/or defibrillation prior to the arrival of basic life-support units, and the results of the cardiopulmonary resuscitation maneuvers. Methods: A prospective, descriptive, observational study of adult non-traumatic out hospital cardiac arrest patients was conducted. The patients were initially assisted by basic life-support units on the island of Mallorca, with one minute of initial capnography monitoring. Results: From July 2018 to March 2020, fifty-nine patients meeting the inclusion criteria were assisted, 76% were men and their mean age was 64.45 (±15.07) years old. The number of emergency lifesaving technicians who participated in the study was 58, they had a mean work experience of 14.05 (±6.7) years. Thirty-seven (63.7%) patients underwent basic life-support by bystanders and in 91.5% of cases the semi-automatic external defibrillator was used. Capnometry values during the first minute were obtained in 34 (58.6%) patients, their mean values were 22 (±19.07) mmHg, 35.5% of patients had values <10 mmHg. In 25.4% of the patients, spontaneous circulation returned during cardiopulmonary resuscitation, and 18.6% were admitted to hospital alive. Conclusion: No correlations were found between initial capnography values scoring above or below 10 mmHg and survival, however, basic life-support maneuvers, and defibrillation by bystanders and first responders, did correlate with survival rates. The average patient assisted in out of hospital cardiac arrest by the basic life-support units sampled was an adult male aged over 65 years.