Improving patient outcomes with compression-only CPR: will bystander CPR rates improve?

Current evidence of survival benefit between chest-compression only versus standard cardiopulmonary resuscitation in out-of-hospital cardiac arrest : Updated systematic review and meta-analysis of randomized controlled trials with trial sequential analysis

BACKGROUND

Evidence to support a better cardiopulmonary resuscitation method between standard vs. continuous chest compression (STD-CPR vs. CCC-CPR) is lacking.

MATERIALS AND METHODS

Our systematic review followed PRISMA guidelines. We searched PubMed, ScienceDirect, EBSCOhost, and ProQuest database from 1985 to 26 September 2019 restricted to randomized controlled trial, human study, and English articles. Quality assessment of between-study heterogeneity and a trial sequential analysis (TSA) were conducted. We estimated overall significance with 80% power and adjusted Z values thresholds using O'Brien-Fleming α‑spending function. Required information size with 21% relative risk using the estimation between-group incidences provided from the median rate across trials was determined. Inconclusive TSA result will lead to size estimation of future RCT. Quality of evidence was analyzed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) Handbook and TSA.

RESULTS

Based on three trials in OHCA with dispatcher-guided and bystander-initiated CPR, our meta-analysis favors CCC-CPR for survival to hospital discharge, compared to STD-CPR (RR [Risk Ratio] = 1.21[1.01-1.46], 95% CI, p = 0.68, I² = 0). However, current meta-analyses with 3031 patients appeared to be inconclusive. There is a significant risk of type 1 error and therefore, results are potentially false positive. It is estimated that a minimal of 4331 patients needed to deem a conclusive result and a total of 5894 patients with similar risk profile required to stabilize statistic results in future trials. Quality of evidence is downgraded to moderate due to serious imprecision based on TSA.

CONCLUSION

Based on these analyses, evidence is inadequate to conclude the superiority of one CPR method over the other. Further trials with larger numbers of patients are needed to deem a conclusive and stable meta-analysis.

Can the British Heart Foundation PocketCPR application improve the performance of chest compressions during bystander resuscitation: A randomised crossover manikin study

This study aims to determine whether the British Heart Foundation PocketCPR training application can improve the depth and rate of chest compression and therefore be confidently recommended for bystander use. A total of 118 candidates were recruited into a randomised crossover manikin trial. Each candidate performed cardiopulmonary resuscitation for 2 min without instruction or performed chest compressions using the PocketCPR application. Candidates then performed a further 2 min of cardiopulmonary resuscitation within the opposite arm. The number of chest compressions performed improved when PocketCPR was used compared to chest compressions when it was not (44.28% vs 40.57%, p < 0.001). The number of chest compressions performed to the required depth was higher in the PocketCPR group (90.86 vs 66.26). The British Heart Foundation PocketCPR application improved the percentage of chest compressions that were performed to the required depth. Despite this, more work is required in order to develop a feedback device that can improve bystander cardiopulmonary resuscitation without creating delay.

Degree of exercise intensity during continuous chest compression in upper-body-trained individuals

Background

Although chest-compression-only cardiopulmonary resuscitation (CCO-CPR) is recommended for lay bystanders, fatigue is easily produced during CCO-CPR. If CCO-CPR can be performed at a lower intensity of exercise, higher resistance to fatigue is expected. Since chest compression is considered to be a submaximal upper body exercise in a steady rhythm and since the unit of load for chest compression is expressed as work rate, we investigated the possibility that peak work rate of the upper body determines the level of exercise intensity during CCO-CPR.

Methods

Twelve sedentary individuals (group Se), 11 rugby players (group R), and 11 swimmers (group Sw) performed 10-min CCO-CPR, and heart rate (HR) and rating of perceived exertion (RPE) were measured as indices of exercise intensity. Multiple linear regression analysis was carried out to assess potential relationships of upper body weight, peak lumbar extension force, peak work rate, and peak oxygen uptake recorded during arm-crank exercise with HR and RPE during CCO-CPR.

Results

Values of peak work rate during arm-crank exercise (Peak WR_-AC) in group Se, group R, and group Sw were 108 ± 12, 139 ± 27, and 146 ± 24 watts, respectively. Values of the latter two groups were significantly higher than the value of group Se (group R, P < 0.01; group Sw, P < 0.001). HR during CCO-CPR increased with time, reaching 127.8 ± 17.6, 114.8 ± 16.5, and 118.1 ± 14.2 bpm at the 10th minute in group Se, group R, and group Sw, respectively. On the other hand, RPE during CCO-CPR increased with time, reaching 16.4 ± 1.4, 15.4 ± 1.7, and 13.9 ± 2.2 at the 10th minute in group Se, group R, and group Sw, respectively. Multiple linear regression analysis showed that only peak WR_-AC affects both HR and RPE at the 10th minute of CCO-CPR (HR, r = −0.458; P < 0.01; RPE, r = −0.384, P < 0.05).

Conclusions

The degree of exercise intensity during CCO-CPR is lower in individuals who have a higher peak work rate of the upper body.

For how long can two emergency medical technicians perform high-quality cardiopulmonary resuscitation?

OBJECTIVE

To determine the duration and obstacles to prolonged on-scene cardiopulmonary resuscitation (CPR), and establish how long a pair of emergency medical technicians (EMTs) can provide high-quality CPR.

METHOD

Intermediate-level EMTs in Gyeonggi-do Province, Republic of Korea completed a survey regarding on-scene CPR. EMTs undergoing routine training took part in a simulation using mannequins. Parameters including compression depth, total number and rate of compressions; occurrence of incorrect hand position and incomplete chest recoil were collected over 16 2-min cycles of CPR (32 min total), with EMTs working in pairs.

RESULT

The simulation study included 43 EMTs. The median duration of on-scene CPR was 3.7 min. Fear of decrease in performance was the main obstacle to continued CPR (n = 188/254 [74.0%]). Standards for high-quality CPR were met at each of the 16 steps of the simulation. Compression rate increased significantly with time. There were no significant changes in any other parameter.

CONCLUSION

Pairs of EMTs maintained high-quality CPR for 16 cycles (32 min) with no decrease in performance. Our findings could provide evidence to recommend guidelines for duration of on-scene CPR for cardiac arrest, particularly in countries where the level and number of ambulance crews are limited.