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2022 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

      ABSTRACT

      This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimising pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.
      This is the sixth in a series of annual International Liaison Committee on Resuscitation (ILCOR) International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations (CoSTR) publications summarising the ILCOR task force analyses of published resuscitation evidence. The 2022 review includes 21 topics addressed with systematic reviews (SysRevs) by the 6 task forces. Although only a SysRev can generate a full CoSTR and updated treatment recommendations, many other topics were reviewed through more streamlined approaches, detailed later.
      Draft CoSTRs for all topics evaluated with SysRevs were posted on a rolling basis from June 2021 through March 2022 on the ILCOR website. These draft CoSTRs include a summary of all data included in the review, as well as draft treatment recommendations. Each CoSTR posting is followed by a 2-week period, during which public comments are accepted. Task forces consider these comments and provide responses. The 21 draft CoSTR statements were viewed ≈27 818 times, and 238 comments were provided as feedback. These CoSTRs are now available online, adding to the existing CoSTR statements.
      This summary contains the final wording of the treatment recommendations and good practice statements as approved by the task forces and by the ILCOR member councils but differs in several respects from the online CoSTRs: The language used to describe the evidence in this summary is not restricted to standard Grading of Recommendations Assessment, Development, and Evaluation (GRADE) terminology, thereby making it more transparent to a wider audience; in some cases, only the high-priority outcomes are reported; and results are presented in tables when possible for improved clarity. The Justification and Evidence-to-Decision Framework Highlights sections are in some cases shortened but aim to provide insight into the rationale behind the treatment recommendations. Complete evidence-to-decision tables are included in Supplemental Appendix A. Last, the task forces have prioritized knowledge gaps requiring future research. Links to the published reviews and full online CoSTRs are provided in the individual sections.
      The CoSTRs are based on task force analysis of the data through the GRADE approach. Each analysis has been detailed in either a SysRev conducted by an expert systematic reviewer or as a task force–led SysRev, and always with input from ILCOR content experts. This GRADE approach rates the certainty of evidence supporting the intervention (predefined by the population, intervention, comparator, and outcome [PICO] question) as high, moderate, low, or very low. Randomised controlled trials (RCTs) begin the analysis as high-certainty evidence, and observational studies begin as low-certainty evidence. Certainty of evidence can be downgraded for risk of bias, inconsistency, indirectness, imprecision, or publication bias; it can be upgraded for a large effect, for a dose-response effect, or if any residual confounding would be thought to decrease the detected effect.
      In addition to the certainty of evidence, each statement includes the pertinent outcome data. The format for the data varies by what is available but ideally includes both relative risk with 95% CI and risk difference with 95% CI. The risk difference is the absolute difference between the risks and is calculated by subtracting the risk in the control group from the risk in the intervention group. This absolute effect enables a more clinically useful assessment of the magnitude of the effect of an intervention and enables calculation of the number needed to treat (number needed to treat=1/risk difference). In cases when the data do not enable absolute effect estimates to be determined, alternative measures of effect such as odds ratios are reported.
      In some cases, a previously published SysRev that meets specific methodological criteria can be used to generate a CoSTR using the GRADE-adolopment process.
      • Schünemann H.J.
      • Wiercioch W.
      • Brozek J.
      • Etxeandia-Ikobaltzeta I.
      • Mustafa R.A.
      • Manja V.
      • Brignardello-Petersen R.
      • Neumann I.
      • Falavigna M.
      • Alhazzani W.
      GRADE Evidence to Decision (EtD) frameworks for adoption, adaptation, and de novo development of trustworthy recommendations: GRADE-ADOLOPMENT..
      Adolopment combines adoption, adaptation, and development and avoids the unnecessary repetition of the SysRev process. It includes the same process of bias assessment and data extraction, with the existing SysRev used as a starting point. Searches are updated if needed, and studies published since the SysRev are added.
      The task forces generate treatment recommendations after weighing the evidence and after discussion. The strength of a recommendation is determined by the task force and is not necessarily tied to the certainty of evidence. Although ILCOR generally has not produced any guidance when the evidence is insufficient to support a recommendation, in some cases, good practice statements have been provided for topics thought to be of particular interest to the resuscitation community. Good practice statements are not recommendations but represent expert opinion in light of very limited data.
      ILCOR’s goal is to review at least 20% of all PICO questions each year so that the CoSTRs reflect current and emerging science. To facilitate this goal, and acknowledging that many PICO topics will not have sufficient new evidence to warrant a SysRev, ILCOR implemented 2 additional levels of evidence review in 2020, which were also used for 2022. Scoping reviews (ScopRevs) are undertaken when there is a lack of clarity on the amount and type of evidence on a broader topic. ScopRevs are broad searches done in multiple databases with a rigor similar to that of a SysRev, but they do not include bias assessments or meta-analyses. The third and least rigorous form of evidence evaluation is the evidence update (EvUp), in which a less comprehensive search is carried out to screen for significant new data and to assess whether there has been sufficient new science to warrant a new ScopRev or SysRev. Both ScopRevs and EvUps can inform a decision about whether a SysRev should be undertaken but are not used to generate a new or updated CoSTR because they do not include bias assessment, GRADE evaluation, or meta-analyses. In this document, the results of ScopRevs are included in a more concise form than in the online version, similar to the SysRevs. EvUps are tabulated by topic at the end of each task force section, with the associated documents provided in Supplemental Appendix B.
      The following topics are addressed in this CoSTR summary:

      Basic Life Support

      • Passive ventilation techniques (SysRev)
      • Minimising pauses in chest compressions (SysRev)
      • Cardiopulmonary resuscitation (CPR) during transport (SysRev)
      • Compressions-airway-breaths (C-A-B) or airway-breaths-compressions (A-B-C) in drowning (new topic; SysRev)
      • Paddle size and placement for defibrillation (EvUp)
      • Barrier devices (EvUp)
      • Chest compression rate (EvUp)
      • Rhythm check timing (EvUp)
      • Timing of CPR cycles (2 minutes versus other; EvUp)
      • Public-access automated external defibrillator (AED) programs (EvUp)
      • Checking for circulation during basic life support (BLS; EvUp)
      • Rescuer fatigue in compression-only CPR (EvUp)
      • Harm from CPR to subjects not in cardiac arrest (EvUp)
      • Harm to rescuers from CPR (EvUp)
      • Hand positioning during compressions (EvUp)
      • Dispatch-assisted compression-only versus conventional CPR (EvUp)
      • Emergency medical services chest compression–only versus conventional CPR (EvUp)
      • Compression-to-ventilation ratio (EvUp)
      • CPR before defibrillation (EvUp)
      • Chest compression depth (EvUp)
      • Chest wall recoil (EvUp)
      • Foreign body airway obstruction (EvUp)
      • Firm surface for CPR (EvUp)
      • In-hospital chest compression–only CPR versus conventional CPR (EvUp)
      • Analysis of rhythm during chest compressions (EvUp)
      • Alternative compression techniques (cough, precordial thump, fist pacing; EvUp)
      • Tidal volumes and ventilation rates (EvUp)
      • Lay rescuer chest compression–only versus conventional CPR (EvUp)
      • Starting CPR (C-A-B versus A-C-B; EvUp)
      • Dispatcher recognition of cardiac arrest (EvUp)
      • Resuscitation care for suspected opioid-associated emergencies (EvUp)
      • CPR before call for help (EvUp)
      • Video-based dispatch (EvUp)
      • Head-up CPR (EvUp)

      Advanced Life Support

      • Targeted temperature management (TTM) after cardiac arrest (SysRev)
      • Point-of-care ultrasound (POCUS) as a diagnostic tool during cardiac arrest (SysRev)
      • Vasopressin and corticosteroids for cardiac arrest (SysRev)
      • Post–cardiac arrest coronary angiography (CAG; SysRev Update)
      • Vasopressors during cardiac arrest (EvUp)
      • Cardiac arrest from pulmonary embolism (EvUp)

      Pediatric Life Support

      • Public-access devices (SysRev)
      • Pediatric early warning systems (PEWSs; SysRev)
      • Sequence of compression and ventilation (EvUp)
      • Chest compression–only versus conventional CPR (EvUp)
      • Drugs for the treatment of bradycardia (EvUp)
      • Emergency transcutaneous pacing for bradycardia (EvUp)
      • Extracorporeal CPR for pediatric cardiac arrest (EvUp)
      • Intraosseous versus intravenous route of drug administration (EvUp)
      • Sodium bicarbonate administration for children in cardiac arrest (EvUp)
      • TTM (EvUp)

      Neonatal Life Support

      • Maintaining normal temperature immediately after birth in late preterm and term infants (SysRev)
      • Suctioning clear amniotic fluid at birth (SysRev)
      • Tactile stimulation for resuscitation immediately after birth (SysRev)
      • Delivery room heart rate monitoring to improve outcomes for newborn infants (SysRev)
      • Continuous positive airway pressure (CPAP) versus no CPAP for term respiratory distress in the delivery room (SysRev)
      • Supraglottic airways (SGAs) for neonatal resuscitation (SysRev)
      • Respiratory function monitoring during neonatal resuscitation at birth (SysRev)

      Education, Implementation, and Teams

      • Prearrest prediction of survival after in-hospital cardiac arrest (IHCA; SysRev)
      • BLS training for likely rescuers of high-risk populations (SysRev)
      • Patient outcome and resuscitation team members attending advanced life support (ALS) courses (SysRev with EvUp)
      • Blended learning for life support education (SysRev)
      • Faculty development approaches for life support courses (ScopRev)
      • Willingness to provide CPR (EvUp)
      • Team and leadership training (EvUp)
      • Medical emergency teams for adults (EvUp)
      • Community initiatives to promote BLS (EvUp)
      • Debriefing of CPR performance (EvUp)
      • Spaced learning (EvUp)

      First Aid

      • The recovery position for maintenance of adequate ventilation and the prevention of cardiac arrest (SysRev)
      • Oral dilution for caustic substance ingestion (EvUp)
      • Recognition of anaphylaxis (EvUp)
      • Compression wraps for acute closed ankle joint injury (EvUp)
      • Open chest wound dressings (EvUp)
      • Bronchodilators for acute asthma exacerbation (EvUp)
      • Optimal duration of cooling of burns with water (EvUp)
      • Preventive interventions for presyncope (EvUp)
      • Single-stage scoring systems for concussion (EvUp)
      • Cooling techniques for exertional hyperthermia and heatstroke (EvUp)
      • First aid use of supplemental oxygen for acute stroke (EvUp)
      • Methods of glucose administration for hypoglycemia in the first aid setting (EvUp)
      • Pediatric tourniquet types for life-threatening extremity bleeding (EvUp)
      Readers are encouraged to monitor the ILCOR website

      International Liaison Committee on Resuscitation . Consensus on Science With Treatment Recommendations (CoSTR) home page.Accessed February 14, 2022. https://www.ilcor.org/home

      to provide feedback on planned SysRevs and to provide comments when additional draft reviews are posted.

      Basic Life Support

      Passive Ventilation Techniques (SysRev)

      Rationale for Review

      This topic was prioritized by the BLS Task Force because the topic had not been reviewed since the 2015 CoSTR recommendations. This SysRev was registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42021293309). The full text of this CoSTR can be found on the ILCOR website.
      • Ristagno G.
      • Nishiyama C.
      • Ikeyama T.
      • Bray J.
      • Smyth M.
      • Kudenchuk P.
      • Johnson N.
      • Masterson S.
      • Nehme Z.
      • Norii T.

      PICO, Study Design, and Time Frame

      • Population: Adults and children with presumed cardiac arrest in any setting
      • Intervention: Any passive ventilation technique (eg, positioning the body, opening the airway, passive oxygen administration, Boussignac tube, constant flow insufflation of oxygen) in addition to chest compressions
      • Comparator: Standard CPR
      • Outcome:
      • A. Critical: Survival to hospital discharge with good neurological outcome, survival to hospital discharge
      • B. Important: Return of spontaneous circulation (ROSC)
      • Study design: RCTs and nonrandomized studies (non-RCTs, interrupted time series, controlled before-and-after studies, cohort studies) were eligible for inclusion. Unpublished studies (eg, conference abstracts, trial protocols) were excluded.
      • Time frame: All years and all languages were included if there was an English abstract. The literature search was updated to October 16, 2021.

      Consensus on Science

      Two RCTs, 1 observational study, and a very small pilot RCT were identified.
      • Saïssy J.M.
      • Boussignac G.
      • Cheptel E.
      • Rouvin B.
      • Fontaine D.
      • Bargues L.
      • Levecque J.P.
      • Michel A.
      • Brochard L.
      Efficacy of continuous insufflation of oxygen combined with active cardiac compression-decompression during out-of-hospital cardiorespiratory arrest..
      • Bertrand C.
      • Hemery F.
      • Carli P.
      • Goldstein P.
      • Espesson C.
      • Rüttimann M.
      • Macher J.M.
      • Raffy B.
      • Fuster P.
      • Dolveck F.
      • Boussignac Study Group
      Constant flow insufflation of oxygen as the sole mode of ventilation during out-of-hospital cardiac arrest..
      • Bobrow B.J.
      • Ewy G.A.
      • Clark L.
      • Chikani V.
      • Berg R.A.
      • Sanders A.B.
      • Vadeboncoeur T.F.
      • Hilwig R.W.
      • Kern K.B.
      Passive oxygen insufflation is superior to bag-valve-mask ventilation for witnessed ventricular fibrillation out-of-hospital cardiac arrest..
      • Fuest K.
      • Dorfhuber F.
      • Lorenz M.
      • von Dincklage F.
      • Mörgeli R.
      • Kuhn K.F.
      • Jungwirth B.
      • Kanz K.G.
      • Blobner M.
      • Schaller S.J.
      Comparison of volume-controlled, pressure-controlled, and chest compression-induced ventilation during cardiopulmonary resuscitation with an automated mechanical chest compression device: a randomized clinical pilot study..
      The overall certainty of evidence was rated as very low. All the individual studies were at a critical risk of bias and indirectness. Because of a high degree of heterogeneity, the meta-analyses included only 2 RCTs in which passive ventilation through constant-flow insufflation of oxygen with the aid of a modified tracheal tube was compared with mechanical ventilation.
      • Saïssy J.M.
      • Boussignac G.
      • Cheptel E.
      • Rouvin B.
      • Fontaine D.
      • Bargues L.
      • Levecque J.P.
      • Michel A.
      • Brochard L.
      Efficacy of continuous insufflation of oxygen combined with active cardiac compression-decompression during out-of-hospital cardiorespiratory arrest..
      ,
      • Bertrand C.
      • Hemery F.
      • Carli P.
      • Goldstein P.
      • Espesson C.
      • Rüttimann M.
      • Macher J.M.
      • Raffy B.
      • Fuster P.
      • Dolveck F.
      • Boussignac Study Group
      Constant flow insufflation of oxygen as the sole mode of ventilation during out-of-hospital cardiac arrest..
      The observational study evaluated passive oxygen insufflation as part of a minimally interrupted CPR bundle (also including uninterrupted preshock and postshock chest compressions and early epinephrine administration).
      • Bobrow B.J.
      • Ewy G.A.
      • Clark L.
      • Chikani V.
      • Berg R.A.
      • Sanders A.B.
      • Vadeboncoeur T.F.
      • Hilwig R.W.
      • Kern K.B.
      Passive oxygen insufflation is superior to bag-valve-mask ventilation for witnessed ventricular fibrillation out-of-hospital cardiac arrest..
      The pilot RCT compared 9 patients who received chest compression–induced ventilation that included CPAP with 11 patients who received volume-controlled ventilation during CPR.
      • Fuest K.
      • Dorfhuber F.
      • Lorenz M.
      • von Dincklage F.
      • Mörgeli R.
      • Kuhn K.F.
      • Jungwirth B.
      • Kanz K.G.
      • Blobner M.
      • Schaller S.J.
      Comparison of volume-controlled, pressure-controlled, and chest compression-induced ventilation during cardiopulmonary resuscitation with an automated mechanical chest compression device: a randomized clinical pilot study..
      Key results are presented in Table 1.
      Table 1Overview of Key Outcomes for Passive Ventilation During CPR Compared With Standard CPR
      Outcomes (importance)Participants, studies, nCertainty of evidence (GRADE)RR (95% CI)Anticipated absolute effects
      Discharge with favourable outcome (critical)1019 patients, 1 observational study
      • Bobrow B.J.
      • Ewy G.A.
      • Clark L.
      • Chikani V.
      • Berg R.A.
      • Sanders A.B.
      • Vadeboncoeur T.F.
      • Hilwig R.W.
      • Kern K.B.
      Passive oxygen insufflation is superior to bag-valve-mask ventilation for witnessed ventricular fibrillation out-of-hospital cardiac arrest..
      Very low1.03 (0.84–1.26)3 patients more/1000 (15 fewer–25 more)
      Survival to ICU discharge (critical)791 patients, 2 RCTs
      • Saïssy J.M.
      • Boussignac G.
      • Cheptel E.
      • Rouvin B.
      • Fontaine D.
      • Bargues L.
      • Levecque J.P.
      • Michel A.
      • Brochard L.
      Efficacy of continuous insufflation of oxygen combined with active cardiac compression-decompression during out-of-hospital cardiorespiratory arrest..
      ,
      • Bertrand C.
      • Hemery F.
      • Carli P.
      • Goldstein P.
      • Espesson C.
      • Rüttimann M.
      • Macher J.M.
      • Raffy B.
      • Fuster P.
      • Dolveck F.
      • Boussignac Study Group
      Constant flow insufflation of oxygen as the sole mode of ventilation during out-of-hospital cardiac arrest..
      Low0.96 (0.31–2.85)1 patient fewer/1000 (14 fewer–38 more)
      Survival to admission (important)791 patients, 2 RCTs
      • Saïssy J.M.
      • Boussignac G.
      • Cheptel E.
      • Rouvin B.
      • Fontaine D.
      • Bargues L.
      • Levecque J.P.
      • Michel A.
      • Brochard L.
      Efficacy of continuous insufflation of oxygen combined with active cardiac compression-decompression during out-of-hospital cardiorespiratory arrest..
      ,
      • Bertrand C.
      • Hemery F.
      • Carli P.
      • Goldstein P.
      • Espesson C.
      • Rüttimann M.
      • Macher J.M.
      • Raffy B.
      • Fuster P.
      • Dolveck F.
      • Boussignac Study Group
      Constant flow insufflation of oxygen as the sole mode of ventilation during out-of-hospital cardiac arrest..
      Low0.92 (0.64–1.24)14 patients fewer/1000 (61 fewer–41 more)
      ROSC (important)791 patients, 2 RCTs
      • Saïssy J.M.
      • Boussignac G.
      • Cheptel E.
      • Rouvin B.
      • Fontaine D.
      • Bargues L.
      • Levecque J.P.
      • Michel A.
      • Brochard L.
      Efficacy of continuous insufflation of oxygen combined with active cardiac compression-decompression during out-of-hospital cardiorespiratory arrest..
      ,
      • Bertrand C.
      • Hemery F.
      • Carli P.
      • Goldstein P.
      • Espesson C.
      • Rüttimann M.
      • Macher J.M.
      • Raffy B.
      • Fuster P.
      • Dolveck F.
      • Boussignac Study Group
      Constant flow insufflation of oxygen as the sole mode of ventilation during out-of-hospital cardiac arrest..
      Low0.98 (0.85–1.12)4 patients fewer/1000 (31 fewer–25 more)
      ROSC (important)1019 patients, 1 observational study
      • Bobrow B.J.
      • Ewy G.A.
      • Clark L.
      • Chikani V.
      • Berg R.A.
      • Sanders A.B.
      • Vadeboncoeur T.F.
      • Hilwig R.W.
      • Kern K.B.
      Passive oxygen insufflation is superior to bag-valve-mask ventilation for witnessed ventricular fibrillation out-of-hospital cardiac arrest..
      Very low0.85 (0.77–1.00)45 patients fewer/1000 (69 fewer–0 more)
      ROSC (important)20 patients, 1 pilot RCT study
      • Fuest K.
      • Dorfhuber F.
      • Lorenz M.
      • von Dincklage F.
      • Mörgeli R.
      • Kuhn K.F.
      • Jungwirth B.
      • Kanz K.G.
      • Blobner M.
      • Schaller S.J.
      Comparison of volume-controlled, pressure-controlled, and chest compression-induced ventilation during cardiopulmonary resuscitation with an automated mechanical chest compression device: a randomized clinical pilot study..
      Very low0.85 (0.77–1.00)45 patients fewer/1000 (69 fewer–0 more)
      CPR indicates cardiopulmonary resuscitation; GRADE, Grading of Recommendations, Assessment, Development, and Evaluation; ICU, intensive care unit; RCT, randomized controlled trial; ROSC, return of spontaneous circulation; and RR, risk ratio.

      Treatment Recommendations

      We suggest against the routine use of passive ventilation techniques during conventional CPR (weak recommendation, very low–certainty evidence).

      Justification and Evidence-to-Decision Framework Highlights

      The complete evidence-to-decision table is included in Supplemental Appendix A.
      Passive ventilation may represent an alternative to intermittent positive-pressure ventilation (PPV). It may shorten interruptions in chest compressions for advanced airway management and may overcome the potential harm from PPV (increased intrathoracic pressure leading to reduced venous return to the heart and reduced coronary perfusion pressure, then increased pulmonary vascular resistance).
      The 2 larger RCTs
      • Saïssy J.M.
      • Boussignac G.
      • Cheptel E.
      • Rouvin B.
      • Fontaine D.
      • Bargues L.
      • Levecque J.P.
      • Michel A.
      • Brochard L.
      Efficacy of continuous insufflation of oxygen combined with active cardiac compression-decompression during out-of-hospital cardiorespiratory arrest..
      ,
      • Bertrand C.
      • Hemery F.
      • Carli P.
      • Goldstein P.
      • Espesson C.
      • Rüttimann M.
      • Macher J.M.
      • Raffy B.
      • Fuster P.
      • Dolveck F.
      • Boussignac Study Group
      Constant flow insufflation of oxygen as the sole mode of ventilation during out-of-hospital cardiac arrest..
      that were included compared intermittent PPV through a tracheal tube with continuous insufflation of oxygen through a modified tracheal tube, that is, a Boussignac tube. The Boussignac tube used in these studies generates a constant tracheal pressure of ≈10 cm H2O. When available, the active compression-decompression device was used to perform CPR. These adjuncts may have played a role in the generation and magnitude of passive ventilation. The included observational study
      • Bobrow B.J.
      • Ewy G.A.
      • Clark L.
      • Chikani V.
      • Berg R.A.
      • Sanders A.B.
      • Vadeboncoeur T.F.
      • Hilwig R.W.
      • Kern K.B.
      Passive oxygen insufflation is superior to bag-valve-mask ventilation for witnessed ventricular fibrillation out-of-hospital cardiac arrest..
      was highly confounded because multiple aspects of the CPR protocols compared were different, including the ventilation strategies, rhythm check timing, compression-to-ventilation ratios, and compression intervals between shocks. Overall, the certainty of evidence was rated as very low primarily because of the risk of bias attributable to indirectness.
      We acknowledge that when emergency medical services systems have adopted a bundle of care that includes minimally interrupted cardiac resuscitation with passive ventilation, it is reasonable to continue with that strategy in the absence of compelling evidence to the contrary.

      Task Force Knowledge Gaps

      • The efficacy of passive ventilation in the lay rescuer setting
      • The optimal method for ensuring a patent airway
      • Whether there is a critical volume of air movement required to maintain ventilation/oxygenation
      • The effectiveness of passive insufflation in children

      Minimising Pauses in Chest Compressions (SysRev)

      Rationale for Review

      This topic was prioritized by the BLS Task Force because the topic had not been reviewed since the 2015 CoSTR. This SysRev was registered in PROSPERO (CRD42019154784). The full text of this CoSTR can be found on the ILCOR website.
      • Olasveengen T.M.
      • Semeraro F.
      • Bray J.
      • Smyth M.
      • Vaillancourt C.
      • Kudenchuk P.
      • Masterson S.
      • Johnson N.
      • Norii T.
      • Nehme Z.

      PICO, Study Design, and Time Frame

      • Population: Adults in cardiac arrest in any setting
      • Intervention: Minimising of pauses in chest compressions (higher CPR or chest compression fraction or shorter perishock pauses compared with control)
      • Comparator: Standard CPR (lower CPR fraction or longer perishock pauses compared with intervention)
      • Outcome:
      • A. Critical: Survival to hospital discharge with good neurological outcome and survival to hospital discharge
      • B. Important: ROSC
      • Study design: RCTs and nonrandomized studies (non-RCTs, interrupted time series, controlled before-and-after studies, cohort studies) were eligible for inclusion. Unpublished studies (eg, conference abstracts, trial protocols) were excluded.
      • Time frame: All years and all languages were included if there was an English abstract. The literature search was updated to December 17, 2021.

      Consensus on Science

      Three RCTs
      • Jost D.
      • Degrange H.
      • Verret C.
      • Hersan O.
      • Banville I.L.
      • Chapman F.W.
      • Lank P.
      • Petit J.L.
      • Fuilla C.
      • Migliani R.
      • DEFI 2005 Work Group
      DEFI 2005: a randomized controlled trial of the effect of automated external defibrillator cardiopulmonary resuscitation protocol on outcome from out-of-hospital cardiac arrest..
      • Beesems S.G.
      • Berdowski J.
      • Hulleman M.
      • Blom M.T.
      • Tijssen J.G.
      • Koster R.W.
      Minimizing pre- and post-shock pauses during the use of an automatic external defibrillator by two different voice prompt protocols : a randomized controlled trial of a bundle of measures..
      • Nichol G.
      • Leroux B.
      • Wang H.
      • Callaway C.W.
      • Sopko G.
      • Weisfeldt M.
      • Stiell I.
      • Morrison L.J.
      • Aufderheide T.P.
      • Cheskes S.
      • ROC Investigators
      Trial of continuous or interrupted chest compressions during CPR..
      and 21 observational studies
      • Bleijenberg E.
      • Koster R.W.
      • de Vries H.
      • Beesems S.G.
      The impact of post-resuscitation feedback for paramedics on the quality of cardiopulmonary resuscitation..
      • Grunau B.
      • Kawano T.
      • Dick W.
      • Straight R.
      • Connolly H.
      • Schlamp R.
      • Scheuermeyer F.X.
      • Fordyce C.B.
      • Barbic D.
      • Tallon J.
      Trends in care processes and survival following prehospital resuscitation improvement initiatives for out-of-hospital cardiac arrest in British Columbia, 2006-2016..
      • Hostler D.
      • Rittenberger J.C.
      • Roth R.
      • Callaway C.W.
      Increased chest compression to ventilation ratio improves delivery of CPR..
      • Lakomek F.
      • Lukas R.P.
      • Brinkrolf P.
      • Mennewisch A.
      • Steinsiek N.
      • Gutendorf P.
      • Sudowe H.
      • Heller M.
      • Kwiecien R.
      • Zarbock A.
      Real-time feedback improves chest compression quality in out-of-hospital cardiac arrest: a prospective cohort study..
      • Lyon R.M.
      • Clarke S.
      • Milligan D.
      • Clegg G.R.
      Resuscitation feedback and targeted education improves quality of pre-hospital resuscitation in Scotland..
      • Olasveengen T.M.
      • Lund-Kordahl I.
      • Steen P.A.
      • Sunde K.
      Out-of hospital advanced life support with or without a physician: effects on quality of CPR and outcome..
      • Christenson J.
      • Andrusiek D.
      • Everson-Stewart S.
      • Kudenchuk P.
      • Hostler D.
      • Powell J.
      • Callaway C.W.
      • Bishop D.
      • Vaillancourt C.
      • Davis D.
      • Resuscitation Outcomes Consortium Investigators.
      Chest compression fraction determines survival in patients with out-of-hospital ventricular fibrillation..
      • Wik L.
      • Olsen J.A.
      • Persse D.
      • Sterz F.
      • Lozano Jr, M.
      • Brouwer M.A.
      • Westfall M.
      • Souders C.M.
      • Travis D.T.
      • Herken U.R.
      Why do some studies find that CPR fraction is not a predictor of survival?.
      • Brouwer T.F.
      • Walker R.G.
      • Chapman F.W.
      • Koster R.W.
      Association between chest compression interruptions and clinical outcomes of ventricular fibrillation out-of-hospital cardiac arrest..
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Morrison L.J.
      • Grunau B.
      • Drennan I.R.
      • Leroux B.
      • Vaillancourt C.
      • Schmidt T.A.
      • Koller A.C.
      • ROC Investigators
      The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest..
      • Vaillancourt C.
      • Everson-Stewart S.
      • Christenson J.
      • Andrusiek D.
      • Powell J.
      • Nichol G.
      • Cheskes S.
      • Aufderheide T.P.
      • Berg R.
      • Stiell I.G.
      • Resuscitation Outcomes Consortium Investigators
      The impact of increased chest compression fraction on return of spontaneous circulation for out-of-hospital cardiac arrest patients not in ventricular fibrillation..
      • Rea T.
      • Olsufka M.
      • Yin L.
      • Maynard C.
      • Cobb L.
      The relationship between chest compression fraction and outcome from ventricular fibrillation arrests in prolonged resuscitations..
      • Vaillancourt C.
      • Petersen A.
      • Meier E.N.
      • Christenson J.
      • Menegazzi J.J.
      • Aufderheide T.P.
      • Nichol G.
      • Berg R.
      • Callaway C.W.
      • Idris A.H.
      • Resuscitation Outcomes Consortium Investigators.
      The impact of increased chest compression fraction on survival for out-of-hospital cardiac arrest patients with a non-shockable initial rhythm..
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Powell J.
      • Drennan I.R.
      • Kudenchuk P.
      • Vaillancourt C.
      • Conway W.
      • Stiell I.
      • Stub D.
      • Resuscitation Outcomes Consortium Investigators
      Chest compression fraction: a time dependent variable of survival in shockable out-of-hospital cardiac arrest..
      • Talikowska M.
      • Tohira H.
      • Inoue M.
      • Bailey P.
      • Brink D.
      • Finn J.
      Lower chest compression fraction associated with ROSC in OHCA patients with longer downtimes..
      • Uppiretla A.K.
      • Gangalal G.M.
      • Rao S.
      • Don Bosco D.
      • Sareef S.M.
      • Sampath V.
      Effects of chest compression fraction on return of spontaneous circulation in patients with cardiac arrest; a brief report..
      • Cheskes S.
      • Schmicker R.H.
      • Christenson J.
      • Salcido D.D.
      • Rea T.
      • Powell J.
      • Edelson D.P.
      • Sell R.
      • May S.
      • Menegazzi J.J.
      • Resuscitation Outcomes Consortium (ROC) Investigators
      Perishock pause: an independent predictor of survival from out-of-hospital shockable cardiac arrest..
      • Cheskes S.
      • Schmicker R.H.
      • Verbeek P.R.
      • Salcido D.D.
      • Brown S.P.
      • Brooks S.
      • Menegazzi J.J.
      • Vaillancourt C.
      • Powell J.
      • May S.
      • Resuscitation Outcomes Consortium (ROC) investigators
      The impact of peri-shock pause on survival from out-of-hospital shockable cardiac arrest during the Resuscitation Outcomes Consortium PRIMED trial..
      • Wik L.
      • Kramer-Johansen J.
      • Myklebust H.
      • Sørebø H.
      • Svensson L.
      • Fellows B.
      • Steen P.A.
      Quality of cardiopulmonary resuscitation during out-of-hospital cardiac arrest..
      • Abella B.S.
      • Alvarado J.P.
      • Myklebust H.
      • Edelson D.P.
      • Barry A.
      • O’Hearn N.
      • Vanden Hoek T.L.
      • Becker L.B.
      Quality of cardiopulmonary resuscitation during in-hospital cardiac arrest..
      • Valenzuela T.D.
      • Kern K.B.
      • Clark L.L.
      • Berg R.A.
      • Berg M.D.
      • Berg D.D.
      • Hilwig R.W.
      • Otto C.W.
      • Newburn D.
      • Ewy G.A.
      Interruptions of chest compressions during emergency medical systems resuscitation..
      were identified. The evidence identified was divided into 5 categories, and results are summarised in Table 2:
      Table 2Minimising Pauses in Chest Compressions
      CategoryStudiesCertainty of evidence (GRADE)Main findings
      1. RCTs on interventions that affect pauses3 RCTs
      • Jost D.
      • Degrange H.
      • Verret C.
      • Hersan O.
      • Banville I.L.
      • Chapman F.W.
      • Lank P.
      • Petit J.L.
      • Fuilla C.
      • Migliani R.
      • DEFI 2005 Work Group
      DEFI 2005: a randomized controlled trial of the effect of automated external defibrillator cardiopulmonary resuscitation protocol on outcome from out-of-hospital cardiac arrest..
      • Beesems S.G.
      • Berdowski J.
      • Hulleman M.
      • Blom M.T.
      • Tijssen J.G.
      • Koster R.W.
      Minimizing pre- and post-shock pauses during the use of an automatic external defibrillator by two different voice prompt protocols : a randomized controlled trial of a bundle of measures..
      • Nichol G.
      • Leroux B.
      • Wang H.
      • Callaway C.W.
      • Sopko G.
      • Weisfeldt M.
      • Stiell I.
      • Morrison L.J.
      • Aufderheide T.P.
      • Cheskes S.
      • ROC Investigators
      Trial of continuous or interrupted chest compressions during CPR..
      Very lowNew AED strategies resulted in higher CPR fractions and shorter preshock and postshock pauses but no differences in survival.
      • Jost D.
      • Degrange H.
      • Verret C.
      • Hersan O.
      • Banville I.L.
      • Chapman F.W.
      • Lank P.
      • Petit J.L.
      • Fuilla C.
      • Migliani R.
      • DEFI 2005 Work Group
      DEFI 2005: a randomized controlled trial of the effect of automated external defibrillator cardiopulmonary resuscitation protocol on outcome from out-of-hospital cardiac arrest..
      ,
      • Beesems S.G.
      • Berdowski J.
      • Hulleman M.
      • Blom M.T.
      • Tijssen J.G.
      • Koster R.W.
      Minimizing pre- and post-shock pauses during the use of an automatic external defibrillator by two different voice prompt protocols : a randomized controlled trial of a bundle of measures..
      Continuous chest compression strategy resulted in higher CPR fractions and lower survival to hospital admission; there were no difference in survival to discharge.
      • Nichol G.
      • Leroux B.
      • Wang H.
      • Callaway C.W.
      • Sopko G.
      • Weisfeldt M.
      • Stiell I.
      • Morrison L.J.
      • Aufderheide T.P.
      • Cheskes S.
      • ROC Investigators
      Trial of continuous or interrupted chest compressions during CPR..
      2. Studies comparing before and after or different systems’ CPR fraction6 observational studies
      • Bleijenberg E.
      • Koster R.W.
      • de Vries H.
      • Beesems S.G.
      The impact of post-resuscitation feedback for paramedics on the quality of cardiopulmonary resuscitation..
      • Grunau B.
      • Kawano T.
      • Dick W.
      • Straight R.
      • Connolly H.
      • Schlamp R.
      • Scheuermeyer F.X.
      • Fordyce C.B.
      • Barbic D.
      • Tallon J.
      Trends in care processes and survival following prehospital resuscitation improvement initiatives for out-of-hospital cardiac arrest in British Columbia, 2006-2016..
      • Hostler D.
      • Rittenberger J.C.
      • Roth R.
      • Callaway C.W.
      Increased chest compression to ventilation ratio improves delivery of CPR..
      • Lakomek F.
      • Lukas R.P.
      • Brinkrolf P.
      • Mennewisch A.
      • Steinsiek N.
      • Gutendorf P.
      • Sudowe H.
      • Heller M.
      • Kwiecien R.
      • Zarbock A.
      Real-time feedback improves chest compression quality in out-of-hospital cardiac arrest: a prospective cohort study..
      • Lyon R.M.
      • Clarke S.
      • Milligan D.
      • Clegg G.R.
      Resuscitation feedback and targeted education improves quality of pre-hospital resuscitation in Scotland..
      • Olasveengen T.M.
      • Lund-Kordahl I.
      • Steen P.A.
      • Sunde K.
      Out-of hospital advanced life support with or without a physician: effects on quality of CPR and outcome..
      Very lowOne study evaluated incremental changes in various CPR quality metrics and outcomes over time and found that from 2006–2016 both CPR fraction and the proportion of survivors with favourable survival increased.
      • Grunau B.
      • Kawano T.
      • Dick W.
      • Straight R.
      • Connolly H.
      • Schlamp R.
      • Scheuermeyer F.X.
      • Fordyce C.B.
      • Barbic D.
      • Tallon J.
      Trends in care processes and survival following prehospital resuscitation improvement initiatives for out-of-hospital cardiac arrest in British Columbia, 2006-2016..
      The other studies observing improved CPR fractions and perishock pauses did not observe significant improvements in survival.
      • Bleijenberg E.
      • Koster R.W.
      • de Vries H.
      • Beesems S.G.
      The impact of post-resuscitation feedback for paramedics on the quality of cardiopulmonary resuscitation..
      ,
      • Hostler D.
      • Rittenberger J.C.
      • Roth R.
      • Callaway C.W.
      Increased chest compression to ventilation ratio improves delivery of CPR..
      • Lakomek F.
      • Lukas R.P.
      • Brinkrolf P.
      • Mennewisch A.
      • Steinsiek N.
      • Gutendorf P.
      • Sudowe H.
      • Heller M.
      • Kwiecien R.
      • Zarbock A.
      Real-time feedback improves chest compression quality in out-of-hospital cardiac arrest: a prospective cohort study..
      • Lyon R.M.
      • Clarke S.
      • Milligan D.
      • Clegg G.R.
      Resuscitation feedback and targeted education improves quality of pre-hospital resuscitation in Scotland..
      • Olasveengen T.M.
      • Lund-Kordahl I.
      • Steen P.A.
      • Sunde K.
      Out-of hospital advanced life support with or without a physician: effects on quality of CPR and outcome..
      3. Associations between chest compression pauses and outcomes5 observational studies
      • Christenson J.
      • Andrusiek D.
      • Everson-Stewart S.
      • Kudenchuk P.
      • Hostler D.
      • Powell J.
      • Callaway C.W.
      • Bishop D.
      • Vaillancourt C.
      • Davis D.
      • Resuscitation Outcomes Consortium Investigators.
      Chest compression fraction determines survival in patients with out-of-hospital ventricular fibrillation..
      • Wik L.
      • Olsen J.A.
      • Persse D.
      • Sterz F.
      • Lozano Jr, M.
      • Brouwer M.A.
      • Westfall M.
      • Souders C.M.
      • Travis D.T.
      • Herken U.R.
      Why do some studies find that CPR fraction is not a predictor of survival?.
      • Brouwer T.F.
      • Walker R.G.
      • Chapman F.W.
      • Koster R.W.
      Association between chest compression interruptions and clinical outcomes of ventricular fibrillation out-of-hospital cardiac arrest..
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Morrison L.J.
      • Grunau B.
      • Drennan I.R.
      • Leroux B.
      • Vaillancourt C.
      • Schmidt T.A.
      • Koller A.C.
      • ROC Investigators
      The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest..
      • Vaillancourt C.
      • Everson-Stewart S.
      • Christenson J.
      • Andrusiek D.
      • Powell J.
      • Nichol G.
      • Cheskes S.
      • Aufderheide T.P.
      • Berg R.
      • Stiell I.G.
      • Resuscitation Outcomes Consortium Investigators
      The impact of increased chest compression fraction on return of spontaneous circulation for out-of-hospital cardiac arrest patients not in ventricular fibrillation..
      Very lowTwo studies found increased CPR fraction to be associated with improved survival,
      • Christenson J.
      • Andrusiek D.
      • Everson-Stewart S.
      • Kudenchuk P.
      • Hostler D.
      • Powell J.
      • Callaway C.W.
      • Bishop D.
      • Vaillancourt C.
      • Davis D.
      • Resuscitation Outcomes Consortium Investigators.
      Chest compression fraction determines survival in patients with out-of-hospital ventricular fibrillation..
      ,
      • Wik L.
      • Olsen J.A.
      • Persse D.
      • Sterz F.
      • Lozano Jr, M.
      • Brouwer M.A.
      • Westfall M.
      • Souders C.M.
      • Travis D.T.
      • Herken U.R.
      Why do some studies find that CPR fraction is not a predictor of survival?.
      whereas 2 did not.
      • Brouwer T.F.
      • Walker R.G.
      • Chapman F.W.
      • Koster R.W.
      Association between chest compression interruptions and clinical outcomes of ventricular fibrillation out-of-hospital cardiac arrest..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Morrison L.J.
      • Grunau B.
      • Drennan I.R.
      • Leroux B.
      • Vaillancourt C.
      • Schmidt T.A.
      • Koller A.C.
      • ROC Investigators
      The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest..
      The fifth study found increasing CPR fraction to be associated with improved ROSC.
      • Vaillancourt C.
      • Everson-Stewart S.
      • Christenson J.
      • Andrusiek D.
      • Powell J.
      • Nichol G.
      • Cheskes S.
      • Aufderheide T.P.
      • Berg R.
      • Stiell I.G.
      • Resuscitation Outcomes Consortium Investigators
      The impact of increased chest compression fraction on return of spontaneous circulation for out-of-hospital cardiac arrest patients not in ventricular fibrillation..
      One study found increasing peri shock pause to be associated with lower survival,
      • Brouwer T.F.
      • Walker R.G.
      • Chapman F.W.
      • Koster R.W.
      Association between chest compression interruptions and clinical outcomes of ventricular fibrillation out-of-hospital cardiac arrest..
      whereas another did not.
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Morrison L.J.
      • Grunau B.
      • Drennan I.R.
      • Leroux B.
      • Vaillancourt C.
      • Schmidt T.A.
      • Koller A.C.
      • ROC Investigators
      The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest..
      4a. Outcomes compared for chest compression pause categories: CPR fraction7 observational studies
      • Christenson J.
      • Andrusiek D.
      • Everson-Stewart S.
      • Kudenchuk P.
      • Hostler D.
      • Powell J.
      • Callaway C.W.
      • Bishop D.
      • Vaillancourt C.
      • Davis D.
      • Resuscitation Outcomes Consortium Investigators.
      Chest compression fraction determines survival in patients with out-of-hospital ventricular fibrillation..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Morrison L.J.
      • Grunau B.
      • Drennan I.R.
      • Leroux B.
      • Vaillancourt C.
      • Schmidt T.A.
      • Koller A.C.
      • ROC Investigators
      The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest..
      • Vaillancourt C.
      • Everson-Stewart S.
      • Christenson J.
      • Andrusiek D.
      • Powell J.
      • Nichol G.
      • Cheskes S.
      • Aufderheide T.P.
      • Berg R.
      • Stiell I.G.
      • Resuscitation Outcomes Consortium Investigators
      The impact of increased chest compression fraction on return of spontaneous circulation for out-of-hospital cardiac arrest patients not in ventricular fibrillation..
      • Rea T.
      • Olsufka M.
      • Yin L.
      • Maynard C.
      • Cobb L.
      The relationship between chest compression fraction and outcome from ventricular fibrillation arrests in prolonged resuscitations..
      • Vaillancourt C.
      • Petersen A.
      • Meier E.N.
      • Christenson J.
      • Menegazzi J.J.
      • Aufderheide T.P.
      • Nichol G.
      • Berg R.
      • Callaway C.W.
      • Idris A.H.
      • Resuscitation Outcomes Consortium Investigators.
      The impact of increased chest compression fraction on survival for out-of-hospital cardiac arrest patients with a non-shockable initial rhythm..
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Powell J.
      • Drennan I.R.
      • Kudenchuk P.
      • Vaillancourt C.
      • Conway W.
      • Stiell I.
      • Stub D.
      • Resuscitation Outcomes Consortium Investigators
      Chest compression fraction: a time dependent variable of survival in shockable out-of-hospital cardiac arrest..
      • Talikowska M.
      • Tohira H.
      • Inoue M.
      • Bailey P.
      • Brink D.
      • Finn J.
      Lower chest compression fraction associated with ROSC in OHCA patients with longer downtimes..
      Very lowOne study showed higher favourable neurological outcome and survival to discharge in arrests with CPR fraction >80% compared with ≤80% in the subgroup with >20-min CPR duration but no differences in survival in the corresponding patient subgroups with 5- or 10-min CPR durations.
      • Rea T.
      • Olsufka M.
      • Yin L.
      • Maynard C.
      • Cobb L.
      The relationship between chest compression fraction and outcome from ventricular fibrillation arrests in prolonged resuscitations..
      Two studies observed higher survival to discharge in arrests with lower CPR fractions (≤40% vs >80%) and lower survival with higher CPR fractions (≤60% vs ≤80% and 60%–79%).
      • Vaillancourt C.
      • Petersen A.
      • Meier E.N.
      • Christenson J.
      • Menegazzi J.J.
      • Aufderheide T.P.
      • Nichol G.
      • Berg R.
      • Callaway C.W.
      • Idris A.H.
      • Resuscitation Outcomes Consortium Investigators.
      The impact of increased chest compression fraction on survival for out-of-hospital cardiac arrest patients with a non-shockable initial rhythm..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Powell J.
      • Drennan I.R.
      • Kudenchuk P.
      • Vaillancourt C.
      • Conway W.
      • Stiell I.
      • Stub D.
      • Resuscitation Outcomes Consortium Investigators
      Chest compression fraction: a time dependent variable of survival in shockable out-of-hospital cardiac arrest..
      One study observed lower ROSC with CPR fraction >80% compared with ≤80%.
      • Talikowska M.
      • Tohira H.
      • Inoue M.
      • Bailey P.
      • Brink D.
      • Finn J.
      Lower chest compression fraction associated with ROSC in OHCA patients with longer downtimes..
      There were no significant differences in outcomes in the remaining 3 studies.
      • Christenson J.
      • Andrusiek D.
      • Everson-Stewart S.
      • Kudenchuk P.
      • Hostler D.
      • Powell J.
      • Callaway C.W.
      • Bishop D.
      • Vaillancourt C.
      • Davis D.
      • Resuscitation Outcomes Consortium Investigators.
      Chest compression fraction determines survival in patients with out-of-hospital ventricular fibrillation..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Morrison L.J.
      • Grunau B.
      • Drennan I.R.
      • Leroux B.
      • Vaillancourt C.
      • Schmidt T.A.
      • Koller A.C.
      • ROC Investigators
      The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest..
      ,
      • Vaillancourt C.
      • Everson-Stewart S.
      • Christenson J.
      • Andrusiek D.
      • Powell J.
      • Nichol G.
      • Cheskes S.
      • Aufderheide T.P.
      • Berg R.
      • Stiell I.G.
      • Resuscitation Outcomes Consortium Investigators
      The impact of increased chest compression fraction on return of spontaneous circulation for out-of-hospital cardiac arrest patients not in ventricular fibrillation..
      4b. Outcomes compared for chest compression pause categories: perishock pauses4 observational studies
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Morrison L.J.
      • Grunau B.
      • Drennan I.R.
      • Leroux B.
      • Vaillancourt C.
      • Schmidt T.A.
      • Koller A.C.
      • ROC Investigators
      The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Powell J.
      • Drennan I.R.
      • Kudenchuk P.
      • Vaillancourt C.
      • Conway W.
      • Stiell I.
      • Stub D.
      • Resuscitation Outcomes Consortium Investigators
      Chest compression fraction: a time dependent variable of survival in shockable out-of-hospital cardiac arrest..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Christenson J.
      • Salcido D.D.
      • Rea T.
      • Powell J.
      • Edelson D.P.
      • Sell R.
      • May S.
      • Menegazzi J.J.
      • Resuscitation Outcomes Consortium (ROC) Investigators
      Perishock pause: an independent predictor of survival from out-of-hospital shockable cardiac arrest..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Verbeek P.R.
      • Salcido D.D.
      • Brown S.P.
      • Brooks S.
      • Menegazzi J.J.
      • Vaillancourt C.
      • Powell J.
      • May S.
      • Resuscitation Outcomes Consortium (ROC) investigators
      The impact of peri-shock pause on survival from out-of-hospital shockable cardiac arrest during the Resuscitation Outcomes Consortium PRIMED trial..
      Three studies observed higher survival in patients with shorter preshock pauses (≤10 s) compared with longer preshock pauses (>10–20 s),
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Morrison L.J.
      • Grunau B.
      • Drennan I.R.
      • Leroux B.
      • Vaillancourt C.
      • Schmidt T.A.
      • Koller A.C.
      • ROC Investigators
      The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Powell J.
      • Drennan I.R.
      • Kudenchuk P.
      • Vaillancourt C.
      • Conway W.
      • Stiell I.
      • Stub D.
      • Resuscitation Outcomes Consortium Investigators
      Chest compression fraction: a time dependent variable of survival in shockable out-of-hospital cardiac arrest..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Christenson J.
      • Salcido D.D.
      • Rea T.
      • Powell J.
      • Edelson D.P.
      • Sell R.
      • May S.
      • Menegazzi J.J.
      • Resuscitation Outcomes Consortium (ROC) Investigators
      Perishock pause: an independent predictor of survival from out-of-hospital shockable cardiac arrest..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Verbeek P.R.
      • Salcido D.D.
      • Brown S.P.
      • Brooks S.
      • Menegazzi J.J.
      • Vaillancourt C.
      • Powell J.
      • May S.
      • Resuscitation Outcomes Consortium (ROC) investigators
      The impact of peri-shock pause on survival from out-of-hospital shockable cardiac arrest during the Resuscitation Outcomes Consortium PRIMED trial..
      and 2 studies observed higher survival in patients with shorter perishock pauses (≤20 s) compared with longer perishock pauses (>20–40 s).
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Powell J.
      • Drennan I.R.
      • Kudenchuk P.
      • Vaillancourt C.
      • Conway W.
      • Stiell I.
      • Stub D.
      • Resuscitation Outcomes Consortium Investigators
      Chest compression fraction: a time dependent variable of survival in shockable out-of-hospital cardiac arrest..
      ,
      • Cheskes S.
      • Schmicker R.H.
      • Christenson J.
      • Salcido D.D.
      • Rea T.
      • Powell J.
      • Edelson D.P.
      • Sell R.
      • May S.
      • Menegazzi J.J.
      • Resuscitation Outcomes Consortium (ROC) Investigators
      Perishock pause: an independent predictor of survival from out-of-hospital shockable cardiac arrest..
      One study did not find improved survival with preshock pause ≤10 s compared with >10 s.
      • Cheskes S.
      • Schmicker R.H.
      • Rea T.
      • Morrison L.J.
      • Grunau B.
      • Drennan I.R.
      • Leroux B.
      • Vaillancourt C.
      • Schmidt T.A.
      • Koller A.C.
      • ROC Investigators
      The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest..
      5. Pauses compared between survivors and nonsurvivors8 observational studies
      • Brouwer T.F.
      • Walker R.G.
      • Chapman F.W.
      • Koster R.W.
      Association between chest compression interruptions and clinical outcomes of ventricular fibrillation out-of-hospital cardiac arrest..
      ,
      • Talikowska M.
      • Tohira H.
      • Inoue M.
      • Bailey P.
      • Brink D.
      • Finn J.
      Lower chest compression fraction associated with ROSC in OHCA patients with longer downtimes..
      • Uppiretla A.K.
      • Gangalal G.M.
      • Rao S.
      • Don Bosco D.
      • Sareef S.M.
      • Sampath V.
      Effects of chest compression fraction on return of spontaneous circulation in patients with cardiac arrest; a brief report..
      • Cheskes S.
      • Schmicker R.H.
      • Christenson J.
      • Salcido D.D.
      • Rea T.
      • Powell J.
      • Edelson D.P.
      • Sell R.
      • May S.
      • Menegazzi J.J.
      • Resuscitation Outcomes Consortium (ROC) Investigators
      Perishock pause: an independent predictor of survival from out-of-hospital shockable cardiac arrest..
      • Cheskes S.
      • Schmicker R.H.
      • Verbeek P.R.
      • Salcido D.D.
      • Brown S.P.
      • Brooks S.
      • Menegazzi J.J.
      • Vaillancourt C.
      • Powell J.
      • May S.
      • Resuscitation Outcomes Consortium (ROC) investigators
      The impact of peri-shock pause on survival from out-of-hospital shockable cardiac arrest during the Resuscitation Outcomes Consortium PRIMED trial..
      • Wik L.
      • Kramer-Johansen J.
      • Myklebust H.
      • Sørebø H.
      • Svensson L.
      • Fellows B.
      • Steen P.A.
      Quality of cardiopulmonary resuscitation during out-of-hospital cardiac arrest..
      • Abella B.S.
      • Alvarado J.P.
      • Myklebust H.
      • Edelson D.P.
      • Barry A.
      • O’Hearn N.
      • Vanden Hoek T.L.
      • Becker L.B.
      Quality of cardiopulmonary resuscitation during in-hospital cardiac arrest..
      • Valenzuela T.D.
      • Kern K.B.
      • Clark L.L.
      • Berg R.A.
      • Berg M.D.
      • Berg D.D.
      • Hilwig R.W.
      • Otto C.W.
      • Newburn D.
      • Ewy G.A.
      Interruptions of chest compressions during emergency medical systems resuscitation..
      Very lowOne study observed higher CPR fractions during the first 5 min in nonsurvivors compared with survivors
      • Brouwer T.F.
      • Walker R.G.
      • Chapman F.W.
      • Koster R.W.
      Association between chest compression interruptions and clinical outcomes of ventricular fibrillation out-of-hospital cardiac arrest..
      ; 1 study observed higher CPR fractions in patients with downtimes >15 min without ROSC
      • Talikowska M.
      • Tohira H.
      • Inoue M.
      • Bailey P.
      • Brink D.
      • Finn J.
      Lower chest compression fraction associated with ROSC in OHCA patients with longer downtimes..
      ; 1 observed higher CPR fractions in patients with ROSC.
      • Uppiretla A.K.
      • Gangalal G.M.
      • Rao S.
      • Don Bosco D.
      • Sareef S.M.
      • Sampath V.
      Effects of chest compression fraction on return of spontaneous circulation in patients with cardiac arrest; a brief report..
      In the remaining 5 studies, no difference was observed.
      • Cheskes S.
      • Schmicker R.H.
      • Christenson J.
      • Salcido D.D.
      • Rea T.
      • Powell J.
      • Edelson D.P.
      • Sell R.
      • May S.
      • Menegazzi J.J.
      • Resuscitation Outcomes Consortium (ROC) Investigators
      Perishock pause: an independent predictor of survival from out-of-hospital shockable cardiac arrest..
      • Cheskes S.
      • Schmicker R.H.
      • Verbeek P.R.
      • Salcido D.D.
      • Brown S.P.
      • Brooks S.
      • Menegazzi J.J.
      • Vaillancourt C.
      • Powell J.
      • May S.
      • Resuscitation Outcomes Consortium (ROC) investigators
      The impact of peri-shock pause on survival from out-of-hospital shockable cardiac arrest during the Resuscitation Outcomes Consortium PRIMED trial..
      • Wik L.
      • Kramer-Johansen J.
      • Myklebust H.
      • Sørebø H.
      • Svensson L.
      • Fellows B.
      • Steen P.A.
      Quality of cardiopulmonary resuscitation during out-of-hospital cardiac arrest..
      • Abella B.S.
      • Alvarado J.P.
      • Myklebust H.
      • Edelson D.P.
      • Barry A.
      • O’Hearn N.
      • Vanden Hoek T.L.
      • Becker L.B.
      Quality of cardiopulmonary resuscitation during in-hospital cardiac arrest..
      • Valenzuela T.D.
      • Kern K.B.
      • Clark L.L.
      • Berg R.A.
      • Berg M.D.
      • Berg D.D.
      • Hilwig R.W.
      • Otto C.W.
      • Newburn D.
      • Ewy G.A.
      Interruptions of chest compressions during emergency medical systems resuscitation..
      AED indicates automated external defibrillator; CPR, cardiopulmonary resuscitation; GRADE, Grading of Recommendations, Assessment, Development, and Evaluation; RCT, randomized controlled trial; and ROSC, return of spontaneous circulation.
      • 1.
        RCTs designed to evaluate interventions affecting quality of CPR
      • 2.
        Observational studies comparing outcomes before and after interventions designed to improve quality of care (including pauses in chest compressions) or between different systems that had differences in CPR fraction
      • 3.
        Observational studies exploring associations between pauses in chest compressions and outcomes
      • 4.
        Observational studies in which outcomes were compared between groups in different chest compression pause categories
      • 5.
        Observational studies in which pauses in compressions were compared between survivors and nonsurvivors
      The overall certainty of evidence was rated as very low for all outcomes, primarily because of a very serious risk of bias. All the individual studies were at a critical risk of bias attributable to confounding. Because of this and a high degree of heterogeneity, no meta-analyses could be performed, and the individual studies are difficult to interpret.

      Treatment Recommendations

      We suggest that CPR fraction and perishock pauses in clinical practice be monitored as part of a comprehensive quality improvement program for cardiac arrest designed to ensure high-quality CPR delivery and resuscitation care across resuscitation systems (weak recommendation, very low–certainty evidence).
      We suggest that preshock and postshock pauses in chest compressions be as short as possible (weak recommendation, very low–certainty evidence).
      We suggest that the CPR fraction during cardiac arrest (CPR time devoted to compressions) should be as high as possible and be at least 60% (weak recommendation, very low–certainty evidence).

      Justification and Evidence-to-Decision Framework Highlights

      The complete evidence-to-decision table is included in Supplemental Appendix A.
      In making these recommendations, the BLS Task Force considered that low CPR fractions may not necessarily reflect lower quality of CPR, but we felt that it was important to provide a minimum value to aid guideline creators. The consensus within the resuscitation community is that high-quality CPR is important for patient outcomes and that high-quality CPR includes high CPR or chest compression fraction and short peri shock pauses. Although the exact targets of these CPR metrics are uncertain, the strong belief in the benefit of minimising pauses in compressions (along with the physiological rationale for the detrimental effect of no compressions) makes prospective clinical trials of long versus short compression pauses unlikely. The evidence identified in this review was either indirect (in that the interventional studies were developed for related purposes) or observational. Observational studies are challenged by the association between pauses in compressions and good outcome because resuscitation attempts of short duration in patients with shockable rhythms tend to have better outcomes than resuscitation attempts of long duration in patients with nonshockable rhythms. The number and proportion of pauses will depend on both cardiac rhythm and the duration of the resuscitation attempt; therefore, an optimal target will depend on the cardiac arrest characteristics. These factors make interpreting observational data and providing guidance for CPR metrics particularly challenging.
      Experimental animal data indicate possible positive effects of postconditioning (improved cardiac and neurological function in animals treated with short, controlled pauses during initial CPR).
      • Matsuura T.R.
      • Bartos J.A.
      • Tsangaris A.
      • Shekar K.C.
      • Olson M.D.
      • Riess M.L.
      • Bienengraeber M.
      • Aufderheide T.P.
      • Neumar R.W.
      • Rees J.N.
      Early effects of prolonged cardiac arrest and ischemic postconditioning during cardiopulmonary resuscitation on cardiac and brain mitochondrial function in pigs..
      ,
      • Segal N.
      • Matsuura T.
      • Caldwell E.
      • Sarraf M.
      • McKnite S.
      • Zviman M.
      • Aufderheide T.P.
      • Halperin H.R.
      • Lurie K.G.
      • Yannopoulos D.
      Ischemic postconditioning at the initiation of cardiopulmonary resuscitation facilitates functional cardiac and cerebral recovery after prolonged untreated ventricular fibrillation..
      There are no human data to inform postconditioning during cardiac arrest. Weighing a theoretical possibility of positive effects from limited pauses in chest compressions against a certain detrimental effect of lack of chest compressions, we believe that it is reasonable to assume that there is a low risk of harm from a lack of chest compression pauses and that the possibility for desirable effects from fewer pauses outweighs this.

      Task Force Knowledge Gaps

      • Effect of a strategy of minimising pauses in compressions compared with longer pauses in compressions
      • Evaluation of limited pauses in compressions as part of a postconditioning strategy in humans
      • Optimal pauses and CPR metrics for various subgroups (shockable versus nonshockable, short versus longer resuscitations, etc)

      CPR During Transport (SysRev)

      Rationale for Review

      A ScopRev was completed for the 2020 CoSTR, and this topic was subsequently prioritized by the BLS Task Force. This SysRev was registered in PROSPERO (CRD42021240615). The full text of these CoSTRs can be found on the ILCOR website.
      • Smyth M.
      • Smith C.
      • Ristagno G.
      • Bray J.
      • Chung S.
      • Dainty K.
      • Folke F.
      • Ikeyama T.
      • Johnsen N.
      • Kudenchuk P.

      PICO, Study Design, and Time Frame

      • Population: Adults and children receiving CPR after out-of-hospital cardiac arrest (OHCA)
      • Intervention: Transport with ongoing CPR
      • Comparator: Completing CPR on scene (until ROSC or termination of resuscitation)
      • Outcome:
      • Critical: Survival to hospital discharge with good neurological outcome and survival to hospital discharge
      • Important: Quality of CPR metrics on scene versus during transport (reported outcomes may include rate of chest compressions, depth of chest compressions, chest compression fraction, interruptions to chest compressions, leaning on chest/incomplete release, rate of ventilation, volume of ventilation, duration of ventilation, pressure of ventilation), ROSC
      • Study design: RCTs and nonrandomized studies (non-RCTs, interrupted time series, controlled before-and-after studies, cohort studies) were eligible for inclusion. Unpublished studies (eg, conference abstracts, trial protocols) were excluded.
      • Time frame: All years and all languages were included if there was an English abstract. The literature search was updated to June 15, 2021.

      Consensus on Science

      The identified studies were divided into those evaluating the effect of transport with ongoing CPR on CPR quality and those evaluating the effect of transport with ongoing CPR on patient outcomes (survival). These results are reported in separate tables (Tables 3 and 4). The studies evaluating the effect of transport with ongoing CPR on CPR quality included a wide range of quality outcomes, including the impact of transport on the following:
      Table 3Effect of Transport on CPR Quality
      CategoryStudiesCertainty of evidence (GRADE)Main findings
      Correct hand positioning2 manikin studies
      • Havel C.
      • Schreiber W.
      • Riedmuller E.
      • Haugk M.
      • Richling N.
      • Trimmel H.
      • Malzer R.
      • Sterz F.
      • Herkner H.
      Quality of closed chest compression in ambulance vehicles, flying helicopters and at the scene..
      ,
      • Putzer G.
      • Braun P.
      • Zimmermann A.
      • Pedross F.
      • Strapazzon G.
      • Brugger H.
      • Paal P.
      LUCAS compared to manual cardiopulmonary resuscitation is more effective during helicopter rescue-a prospective, randomized, cross-over manikin study..
      Very lowSimulated helicopter rescue; 1 study with fewer correct compressions in flight,
      • Putzer G.
      • Braun P.
      • Zimmermann A.
      • Pedross F.
      • Strapazzon G.
      • Brugger H.
      • Paal P.
      LUCAS compared to manual cardiopulmonary resuscitation is more effective during helicopter rescue-a prospective, randomized, cross-over manikin study..
      1 study with no difference
      • Havel C.
      • Schreiber W.
      • Riedmuller E.
      • Haugk M.
      • Richling N.
      • Trimmel H.
      • Malzer R.
      • Sterz F.
      • Herkner H.
      Quality of closed chest compression in ambulance vehicles, flying helicopters and at the scene..
      Chest compression rate5 observational studies
      • Olasveengen T.M.
      • Wik L.
      • Steen P.A.
      Quality of cardiopulmonary resuscitation before and during transport in out-of-hospital cardiac arrest..
      • Ødegaard S.
      • Olasveengen T.
      • Steen P.A.
      • Kramer-Johansen J.
      The effect of transport on quality of cardiopulmonary resuscitation in out-of-hospital cardiac arrest..
      • Roosa J.R.
      • Vadeboncoeur T.F.
      • Dommer P.B.
      • Panchal A.R.
      • Venuti M.
      • Smith G.
      • Silver A.
      • Mullins M.
      • Spaite D.
      • Bobrow B.J.
      CPR variability during ground ambulance transport of patients in cardiac arrest..
      • Russi C.S.
      • Myers L.A.
      • Kolb L.J.
      • Lohse C.M.
      • Hess E.P.
      • White R.D.
      A comparison of chest compression quality delivered during on-scene and ground transport cardiopulmonary resuscitation..
      • Cheskes S.
      • Byers A.
      • Zhan C.
      • Verbeek P.R.
      • Ko D.
      • Drennan I.R.
      • Buick J.E.
      • Brooks S.C.
      • Lin S.
      • Taher A.
      • Rescu Epistry Investigators
      CPR quality during out-of-hospital cardiac arrest transport..


      4 manikin studies
      • Havel C.
      • Schreiber W.
      • Riedmuller E.
      • Haugk M.
      • Richling N.
      • Trimmel H.
      • Malzer R.
      • Sterz F.
      • Herkner H.
      Quality of closed chest compression in ambulance vehicles, flying helicopters and at the scene..
      ,
      • Sunde K.
      • Wik L.
      • Steen P.A.
      Quality of mechanical, manual standard and active compression-decompression CPR on the arrest site and during transport in a manikin model..
      • Thomassen O.
      • Skaiaa S.C.
      • Assmuss J.
      • Østerås Ø
      • Heltne J.K.
      • Wik L.
      • Brattebo G.
      Mountain rescue cardiopulmonary resuscitation: a comparison between manual and mechanical chest compressions during manikin cardio resuscitation..
      • Abrams T.
      • Torfason L.
      Evaluation of the quality of manual, compression-only cardiopulmonary resuscitation in a moving ski patrol toboggan..
      Very lowOne study with slightly faster compressions during transport,
      • Cheskes S.
      • Byers A.
      • Zhan C.
      • Verbeek P.R.
      • Ko D.
      • Drennan I.R.
      • Buick J.E.
      • Brooks S.C.
      • Lin S.
      • Taher A.
      • Rescu Epistry Investigators
      CPR quality during out-of-hospital cardiac arrest transport..
      2 showed increased variation,
      • Roosa J.R.
      • Vadeboncoeur T.F.
      • Dommer P.B.
      • Panchal A.R.
      • Venuti M.
      • Smith G.
      • Silver A.
      • Mullins M.
      • Spaite D.
      • Bobrow B.J.
      CPR variability during ground ambulance transport of patients in cardiac arrest..
      ,
      • Cheskes S.
      • Byers A.
      • Zhan C.
      • Verbeek P.R.
      • Ko D.
      • Drennan I.R.
      • Buick J.E.
      • Brooks S.C.
      • Lin S.
      • Taher A.
      • Rescu Epistry Investigators
      CPR quality during out-of-hospital cardiac arrest transport..
      3 showed no difference.
      • Olasveengen T.M.
      • Wik L.
      • Steen P.A.
      Quality of cardiopulmonary resuscitation before and during transport in out-of-hospital cardiac arrest..
      ,
      • Ødegaard S.
      • Olasveengen T.
      • Steen P.A.
      • Kramer-Johansen J.
      The effect of transport on quality of cardiopulmonary resuscitation in out-of-hospital cardiac arrest..
      ,
      • Russi C.S.
      • Myers L.A.
      • Kolb L.J.
      • Lohse C.M.
      • Hess E.P.
      • White R.D.
      A comparison of chest compression quality delivered during on-scene and ground transport cardiopulmonary resuscitation..
      Manikin studies had divergent results.
      • Havel C.
      • Schreiber W.
      • Riedmuller E.
      • Haugk M.
      • Richling N.
      • Trimmel H.
      • Malzer R.
      • Sterz F.
      • Herkner H.
      Quality of closed chest compression in ambulance vehicles, flying helicopters and at the scene..
      ,
      • Sunde K.
      • Wik L.
      • Steen P.A.
      Quality of mechanical, manual standard and active compression-decompression CPR on the arrest site and during transport in a manikin model..
      • Thomassen O.
      • Skaiaa S.C.
      • Assmuss J.
      • Østerås Ø
      • Heltne J.K.
      • Wik L.
      • Brattebo G.
      Mountain rescue cardiopulmonary resuscitation: a comparison between manual and mechanical chest compressions during manikin cardio resuscitation..
      • Abrams T.
      • Torfason L.
      Evaluation of the quality of manual, compression-only cardiopulmonary resuscitation in a moving ski patrol toboggan..
      Chest compression depth4 observational studies
      • Ødegaard S.
      • Olasveengen T.
      • Steen P.A.
      • Kramer-Johansen J.
      The effect of transport on quality of cardiopulmonary resuscitation in out-of-hospital cardiac arrest..
      • Roosa J.R.
      • Vadeboncoeur T.F.
      • Dommer P.B.
      • Panchal A.R.
      • Venuti M.
      • Smith G.
      • Silver A.
      • Mullins M.
      • Spaite D.
      • Bobrow B.J.
      CPR variability during ground ambulance transport of patients in cardiac arrest..
      • Russi C.S.
      • Myers L.A.
      • Kolb L.J.
      • Lohse C.M.
      • Hess E.P.
      • White R.D.
      A comparison of chest compression quality delivered during on-scene and ground transport cardiopulmonary resuscitation..
      • Cheskes S.
      • Byers A.
      • Zhan C.
      • Verbeek P.R.
      • Ko D.
      • Drennan I.R.
      • Buick J.E.
      • Brooks S.C.
      • Lin S.
      • Taher A.
      • Rescu Epistry Investigators
      CPR quality during out-of-hospital cardiac arrest transport..


      4 manikin studies
      • Havel C.
      • Schreiber W.
      • Riedmuller E.
      • Haugk M.
      • Richling N.
      • Trimmel H.
      • Malzer R.
      • Sterz F.
      • Herkner H.
      Quality of closed chest compression in ambulance vehicles, flying helicopters and at the scene..
      ,
      • Sunde K.
      • Wik L.
      • Steen P.A.
      Quality of mechanical, manual standard and active compression-decompression CPR on the arrest site and during transport in a manikin model..
      • Thomassen O.
      • Skaiaa S.C.
      • Assmuss J.
      • Østerås Ø
      • Heltne J.K.
      • Wik L.
      • Brattebo G.
      Mountain rescue cardiopulmonary resuscitation: a comparison between manual and mechanical chest compressions during manikin cardio resuscitation..
      • Abrams T.
      • Torfason L.
      Evaluation of the quality of manual, compression-only cardiopulmonary resuscitation in a moving ski patrol toboggan..
      Very lowOne study with deeper compressions
      • Cheskes S.
      • Byers A.
      • Zhan C.
      • Verbeek P.R.
      • Ko D.
      • Drennan I.R.
      • Buick J.E.
      • Brooks S.C.
      • Lin S.
      • Taher A.
      • Rescu Epistry Investigators
      CPR quality during out-of-hospital cardiac arrest transport..
      and 1 with more correct depth
      • Russi C.S.
      • Myers L.A.
      • Kolb L.J.
      • Lohse C.M.
      • Hess E.P.
      • White R.D.
      A comparison of chest compression quality delivered during on-scene and ground transport cardiopulmonary resuscitation..
      during transport, 2 with no difference.
      • Ødegaard S.
      • Olasveengen T.
      • Steen P.A.
      • Kramer-Johansen J.
      The effect of transport on quality of cardiopulmonary resuscitation in out-of-hospital cardiac arrest..
      ,
      • Roosa J.R.
      • Vadeboncoeur T.F.
      • Dommer P.B.
      • Panchal A.R.
      • Venuti M.
      • Smith G.
      • Silver A.
      • Mullins M.
      • Spaite D.
      • Bobrow B.J.
      CPR variability during ground ambulance transport of patients in cardiac arrest..
      Manikin studies had divergent results.
      • Havel C.
      • Schreiber W.
      • Riedmuller E.
      • Haugk M.
      • Richling N.
      • Trimmel H.
      • Malzer R.
      • Sterz F.
      • Herkner H.
      Quality of closed chest compression in ambulance vehicles, flying helicopters and at the scene..
      ,
      • Sunde K.
      • Wik L.
      • Steen P.A.
      Quality of mechanical, manual standard and active compression-decompression CPR on the arrest site and during transport in a manikin model..
      • Thomassen O.
      • Skaiaa S.C.
      • Assmuss J.
      • Østerås Ø
      • Heltne J.K.
      • Wik L.
      • Brattebo G.
      Mountain rescue cardiopulmonary resuscitation: a comparison between manual and mechanical chest compressions during manikin cardio resuscitation..
      • Abrams T.
      • Torfason L.
      Evaluation of the quality of manual, compression-only cardiopulmonary resuscitation in a moving ski patrol toboggan..
      Pauses1 manikin study
      • Abrams T.
      • Torfason L.
      Evaluation of the quality of manual, compression-only cardiopulmonary resuscitation in a moving ski patrol toboggan..
      Very lowPauses during transport within guidelines
      • Abrams T.
      • Torfason L.
      Evaluation of the quality of manual, compression-only cardiopulmonary resuscitation in a moving ski patrol toboggan..
      Leaning on the chest/incomplete release2 manikin studies
      • Putzer G.
      • Braun P.
      • Zimmermann A.
      • Pedross F.
      • Strapazzon G.
      • Brugger H.
      • Paal P.
      LUCAS compared to manual cardiopulmonary resuscitation is more effective during helicopter rescue-a prospective, randomized, cross-over manikin study..
      ,
      • Abrams T.
      • Torfason L.
      Evaluation of the quality of manual, compression-only cardiopulmonary resuscitation in a moving ski patrol toboggan..
      Very lowManikin studies with divergent results
      • Putzer G.
      • Braun P.
      • Zimmermann A.
      • Pedross F.
      • Strapazzon G.
      • Brugger H.
      • Paal P.
      LUCAS compared to manual cardiopulmonary resuscitation is more effective during helicopter rescue-a prospective, randomized, cross-over manikin study..
      ,
      • Abrams T.
      • Torfason L.
      Evaluation of the quality of manual, compression-only cardiopulmonary resuscitation in a moving ski patrol toboggan..