The physiological effect on rescuers of doing 2min of uninterrupted chest compressions.

OBJECTIVES: To analyse how rescuers tolerate the effort derived of giving uninterrupted chest compressions during 2min. MATERIALS AND METHODS: Twenty-three healthy volunteers, nurses and doctors of the Intensive Care Unit (ICU), members of the hospital cardiac arrest team, were enrolled in the study. Using a training manikin, participants were asked to perform chest compressions during 2min at a rate of 100min(-1). The oxygen saturation and cardiac rate of the subjects were monitored using pulse oximetry before and after one and 2min performing chest compressions. The percentage of the maximal heart rate of the rescuer over the theoretical maximum allowed in a conventional stress test was calculated, taking into account age and body mass index (BMI) of the subjects. Fatigue was measured using a visual analogical scale (VAS). RESULTS: The means (+/-S.D.) of chest compressions in the first and second minutes were 103+/-12, and 104+/-11, respectively. The mean percent of the maximum heart rate observed was 61+/-8%. None of the subjects had difficulties to complete the test. All subjects recovered their basal values in less than 2min, and the mean value recorded in the VAS was 3+/-2. CONCLUSIONS: The practice of uninterrupted chest compressions during 2min by the same rescuer is well tolerated by health professionals trained in cardiopulmonary resuscitation (CPR).

Assessing practical skills in cardiopulmonary resuscitation: Discrepancy between standard visual evaluation and a mechanical feedback device.

This paper aims to analyze agreement in the assessment of external chest compressions (ECC) by 3 human raters and dedicated feedback software.While 54 volunteer health workers (medical transport technicians), trained and experienced in cardiopulmonary resuscitation (CPR), performed a complete sequence of basic CPR maneuvers on a manikin incorporating feedback software (Laerdal PC v 4.2.1 Skill Reporting Software) (L), 3 expert CPR instructors (A, B, and C) visually assessed ECC, evaluating hand placement, compression depth, chest decompression, and rate. We analyzed the concordance among the raters (A, B, and C) and between the raters and L with Cohen's kappa coefficient (K), intraclass correlation coefficients (ICC), Bland-Altman plots, and survival-agreement plots.The agreement (expressed as Cohen's K and ICC) was ≥0.54 in only 3 instances and was ≤0.45 in more than half. Bland-Altman plots showed significant dispersion of the data. The survival-agreement plot showed a high degree of discordance between pairs of raters (A-L, B-L, and C-L) when the level of tolerance was set low.In visual assessment of ECC, there is a significant lack of agreement among accredited raters and significant dispersion and inconsistency in data, bringing into question the reliability and validity of this method of measurement.