CPR compression strategy 30:2 is difficult to adhere to, but has better survival than continuous chest compressions when done correctly

Are instructors correctly gauging ventilation competence acquired by course attendees?

Achievement of adequate ventilation skills during training courses is mainly based on instructors' perception of attendees' capability to ventilate with correct rate and chest compression:ventilation ratio, while leading to chest raising, as evidence of adequate tidal volume. Accuracy in evaluating ventilation competence was assessed in 20 ACLS provider course attendees, by comparing course instructors' evaluation with measures from a ventilation feedback device. According to course instructors, all candidates acquired adequate ventilation competence. However, data from the feedback device indicated a ventilation not aligned with current guidelines, with higher tidal volume and lower rate (p < 0.01). Deploying quality ventilation during CPR is a skill whose acquisition starts with effective training. Therefore, course instructors' capability to accurately evaluate attendees' ventilation maneuvers is crucial.

Bag-Valve-Mask Ventilation and Survival From Out-of-Hospital Cardiac Arrest: A Multicenter Study

BACKGROUND

Few studies have measured ventilation during early cardiopulmonary resuscitation (CPR) before advanced airway placement. Resuscitation guidelines recommend pauses after every 30 chest compressions to deliver ventilations. The effectiveness of bag-valve-mask ventilation delivered during the pause in chest compressions is unknown. We sought to determine: (1) the incidence of lung inflation with bag-valve-mask ventilation during 30:2 CPR; and (2) the association of ventilation with outcomes after out-of-hospital cardiac arrest.

METHODS

We studied patients with out-of-hospital cardiac arrest from 6 sites of the Resuscitation Outcomes Consortium CCC study (Trial of Continuous Compressions versus Standard CPR in Patients with Out-of-Hospital Cardiac Arrest). We analyzed patients assigned to the 30:2 CPR arm with ≥2 minutes of thoracic bioimpedance signal recorded with a cardiac defibrillator/monitor. Detectable ventilation waveforms were defined as having a bioimpedance amplitude ≥0.5 Ω (corresponding to ≥250 mL VT) and a duration ≥1 s. We defined a chest compression pause as a 3- to 15-s break in chest compressions. We compared the incidence of ventilation and outcomes in 2 groups: patients with ventilation waveforms in <50% of pauses (group 1) versus those with waveforms in ≥50% of pauses (group 2).

RESULTS

Among 1976 patients, the mean age was 65 years; 66% were male. From the start of chest compressions until advanced airway placement, mean±SD duration of 30:2 CPR was 9.8±4.9 minutes. During this period, we identified 26 861 pauses in chest compressions; 60% of patients had ventilation waveforms in <50% of pauses (group 1, n=1177), and 40% had waveforms in ≥50% of pauses (group 2, n=799). Group 1 had a median of 12 pauses and 2 ventilations per patient versus group 2, which had 12 pauses and 12 ventilations per patient. Group 2 had higher rates of prehospital return of spontaneous circulation (40.7% versus 25.2%; P<0.0001), survival to hospital discharge (13.5% versus 4.1%; P<0.0001), and survival with favorable neurological outcome (10.6% versus 2.4%; P<0.0001). These associations persisted after adjustment for confounders.

CONCLUSIONS

In this study, lung inflation occurred infrequently with bag-valve-mask ventilation during 30:2 CPR. Lung inflation in ≥50% of pauses was associated with improved return of spontaneous circulation, survival, and survival with favorable neurological outcome.

Cardiopulmonary Resuscitation: The Importance of the Basics

Cardiac arrest is the loss of organized cardiac activity. Unfortunately, survival to hospital discharge is poor, despite recent scientific advances. The goals of cardiopulmonary resuscitation (CPR) are to restore circulation and identify and correct an underlying etiology. High-quality compressions remain the foundation of CPR, optimizing coronary and cerebral perfusion pressure. High-quality compressions must be performed at the appropriate rate and depth. Interruptions in compressions are detrimental to management. Mechanical compression devices are not associated with improved outcomes but can assist in several situations.

Continuous compression with asynchronous ventilation improves CPR prognosis? A meta-analysis from human and animal studies

BACKGROUND

The cardiopulmonary resuscitation (CPR) compression to ventilation strategy remains controversial. We conducted a meta-analysis to compare the outcomes between continuous chest compressions CPR with asynchronous ventilation (CCC-CPR) and interrupted chest compressions CPR with synchronous ventilation (ICC-CPR) in cardiac arrest.

METHODS

PubMed, Web of Science, Embase, MEDLINE (Ovid/LWW) and the Cochrane Libraries were searched up from inception to July 31, 2022. Human and animal studies comparing CCC-CPR versus ICC-CPR were included. Outcome variables were return of spontaneous circulation (ROSC), time to ROSC, survival to discharge, 1-month survival, survival at 4 h, good neurological function, mean arterial pressure (MAP) and other clinical parameters. Jadad Scale and Newcastle-Ottawa Scale were used to assess the study quality and risk of bias.

RESULTS

The systematic search identified eight studies on humans and twelve studies on animal trials. There were no significant differences in ROSC (odd ratios [OR] 1.07; 95% confidence interval [CI]: 0.86-1.32; P = 0.55), survival to hospital discharge (OR 1.04; 95%CI 0.77-1.42; P = 0.79), 1-month survival (OR 1.07; 95%CI 0.84-1.36; P = 0.57), and good neurological outcome (OR 0.92; 95%CI 0.84-1.01, P = 0.09) between CCC-CPR and ICC-CPR in human studies. In animal trials, CCC-CPR had significantly higher rate of ROSC (OR = 1.81; 95% CI: 0.94-3.49; P = 0.07), survival at 4 h (OR 2.57; 95% CI: 1.16-5.72; P = 0.02) and MAP (mean difference [MD] 0.79, 95% CI: 0.04-1.53; P = 0.04), even though no significant differences in ROSC time, arterial potential of hydrogen (pH) and partial tension of carbon dioxide (PaCO2).

CONCLUSION

CCC-CPR did not show superiority in human outcomes compared with ICC-CPR, but its effect value was significantly increased in animal experiments. We should take the positive outcomes from animals and apply them to human models, and more physiological mechanisms need to be confirmed in CPR patients with different compression-ventilation strategies to improve the prognosis of cardiac arrest.

The association of race with CPR quality following out-of-hospital cardiac arrest

INTRODUCTION

Previous studies have shown racial disparities in outcomes after out-of-hospital cardiac arrest. Although several treatment factors may account for these differences, there is limited information regarding differences in CPR quality and its effect on survival in underrepresented racial populations.

METHODS

We conducted a secondary analysis of data from patients enrolled in the Pragmatic Airway Resuscitation Trial (PART). We calculated compliance rates with AHA 2015 high quality CPR metrics as well as compliance to intended CPR strategy (30:2 or continuous chest compression) based on the protocol in place for the first responding EMS agency. The primary analysis used general estimating equations logistic regression to examine differences between black and white patients based on EMS-assessed race after adjustment for potential confounders. Sensitivity analyses examined differences using alternate race definitions.

RESULTS

There were 3004 patients enrolled in PART of which 1734 had > 2 minutes of recorded CPR data and an EMS-assessed race (1003 white, 555 black, 176 other). Black patients had higher adjusted odds of compression rate compliance (OR: 1.36, 95% CI: 1.02-1.81) and lower adjusted odds of intended CPR strategy compliance (OR: 0.78, 95% CI: 0.63-0.98) compared to white patients. Of 974 transported to the hospital, there was no difference in compliance metric estimates based on ED-reported race.

CONCLUSION

Compression rate compliance was higher in black patients however compliance with intended strategy was lower based on EMS-assessed race. The remaining metrics showed no difference suggesting that CPR quality differences are not important contributors to the observed outcome disparities by race.

Meta-analysis of chest compression-only versus conventional cardiopulmonary resuscitation by bystanders for adult with out-of-hospital cardiac arrest

BACKGROUND

According to the guidelines of cardiopulmonary resuscitation (CPR) conducted by bystanders, two methods of CPR are feasible: standard CPR (sCPR) with mouth-to-mouth ventilations and continuous chest compression-only CPR (CCC) without rescue breathing. The goal herein, was to evaluate the effect of sCPR (30:2) and CCC on resuscitation outcomes in patients with out-of-hospital cardiac arrest (OHCA) patients.

METHODS

This study was a systematic review and meta-analysis. Using standardized criteria, Pub- Med, Web of Science, Scopus, EMBASE and Cochrane Collaboration were searched for trials assessing the effect of sCPR vs. CCC on resuscitation outcomes after adult OHCA. Random-effects model meta-analysis was applied to calculate the mean deviation (MD), odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Overall, 3 randomized controlled trials and 12 non-randomized trials met the inclusion criteria. Survival to hospital discharge with sCPR was 10.2% compared to 9.3% in the CCC group (OR = 1.04; 95% CI: 0.93-1.16; p = 0.46). Survival to hospital discharge with good neurological outcome measured with the cerebral performance category (CPC 1 or 2) was 6.5% for sCPR vs. 5.8% for CCC (OR = 1.00; 95% CI: 0.84-1.20; p = 0.98). Prehospital return of spontaneous circulation (ROSC) in sCPR and CCC groups was 15.9% and 14.8%, respectively (OR = 1.13; 95% CI: 0.91-1.39; p = 0.26). Survival to hospital admission with ROSC occurred in 29.5% of the sCPR group compared to 28.4% in CCC group (OR = 1.20; 95% CI: 0.89-1.63; p = 0.24).

CONCLUSIONS

This systematic review and meta-analysis concluded that there were no significant differences in the resuscitation outcomes between the use of standard cardiopulmonary resuscitation and chest compression only.