Study Design

Reduced Quality Factors

0 = no serious, - = serious,

- - = very serious

Positive Quality Factors

0 = none, + = one, ++ = multiple

Dichotomous Outcome Summary

Non-Dichotomous Outcome Summary

Brief description

Overall Quality

High, moderate, low,
very low, none

No of studies

Study Type

RoB

Indirectness

Imprecision

Inconsistency

Large Effect

Dose-Response

Confounder

# Intervention with Outcome

# Control with Outcome

RR (95% CI)

Outcome: Favorable neurologic outcome, Survival to discharge, ROSC, Complications

0

Introduction

Minimizing interruptions in chest compressions (CCs) has been associated with improved outcomes (see BLS-16). A 2-minute CC cycle is recommended to optimize cardiac output but still allow pauses for patient assessment (see BLS-15). If ROSC is suspected during a 2-minute CC cycle the rescuers have the option of pausing CCs to determine if ROSC is present, or to complete the cycle and assess the patient at the scheduled pause. In human CPR guidelines for children and adults, no evidence was identified to assess this question as of 2020 and the treatment recommendation was to minimize interruptions in chest compressions and avoid pausing to evaluate circulation, without strong suspicion of ROSC.1

Consensus on science

For the most critical outcomes of Favorable neurologic outcome, Survival to discharge, and ROSC, we identified no studies addressing the PICO question.

Treatment recommendation

We suggest interrupting a 2-minute CC cycle only when ROSC is suspected based on a combination of 1) a sudden and persistent increase in ETCO2 of great magnitude (e.g., by ≥ 10 mmHg to reach a value that is ≥ 35 mmHg) and 2) evidence of an arterial pulse distinct from chest compressions.(weak recommendation, expert opinion)

In the absence of capnography data, we recommend against interruption of a 2-minute CC cycle even if ROSC is suspected.(strong recommendation, expert opinion)

Justification of treatment recommendation

Harm to patients undergoing CPR when not actually in cardiac arrest has been shown to be minimal,2 and hands-off time has been associated with non-survival. Additionally, a study in adults with nontraumatic OHCA found that a rise in ETCO2 of ≥ 10 mmHg was highly specific (97%, CI95 91% - 99%) though poorly sensitive for ROSC (33%, CI95 22% - 47%); specificity was 100% for people with non-cardiac causes of CPA (i.e., non-shockable rhythms).3 There is evidence in experimental pigs of significant and potentially clinically meaningful impairment of perfusion (arterial pressure, CoPP) when CC are administered to animals with a spontaneous heartbeat.4

Knowledge gaps

There is no evidence regarding the interruption of 2-minute chest compression cycles in dogs and cats when ROSC is suspected.