Special Circumstances

CPR in Obese Adults and Children

Last Full Review: ILCOR 2025

Obesity is a chronic condition that increases the risk of coronary heart disease, hypertension, type 2 diabetes and other diseases. In the United States (U.S.), the prevalence estimates of obesity during August 2021 to August 2023 was 39.2% in men and 41.3% in women, while the prevalence of severe obesity (Class II, Body Mass Index of 35.0 to 39.9) in adults was 9.4% (Emmerich et al. 2024). The prevalence of obesity among U.S. children and adolescents (ages 2 to 19 years) was 19.7%, or about 14.7 million youths. Providing cardiopulmonary resuscitation (CPR) on severely or morbidly obese individuals presents challenges due to anatomical and physiological differences. The increased adipose tissue in obese persons can impede the delivery of effective chest compressions. A recent scoping review explored the research evidence related to CPR in obese patients.

 

Evidence Summary

A 2024 scoping review by the International Liaison Committee on Resuscitation (ILCOR) (Considine et al. 2024, 100820; Considine et al. 2024; Bray et al. 2025, S34) sought evidence for the use of CPR, including mechanical and extracorporeal cardiopulmonary resuscitation (ECPR), in obese adults and children in any setting with cardiac arrest, compared with no CPR, non-obese patients, or modified CPR for obese patients. Outcomes sought included survival to discharge with good neurological outcome, survival to hospital discharge, return of spontaneous circulation (ROSC), CPR quality measures, CPR timing, techniques and provider outcomes.

Pediatric Patients

Two studies of children and one study in which the age was not reported were included in the evidence analysis. The two pediatric studies (Meert et al. 2016, e543; Srinivasan et al. 2010, e481) reported worse neurological outcomes in obese children than normal weight children at discharge and at 12 months. One study (Srinivasan et al. 2010, e481) reported that ROSC and survival to hospital discharge were less likely in obese children than normal weight children after cardiac arrest. The pediatric evidence was limited but the ILCOR review authors noted that the overall results do not suggest a requirement to deviate from standard CPR protocols. A good practice statement was made that standard CPR protocols should be used in obese pediatric patients.

Adult Patients

There were 15 adult studies in the evidence reviewed that reported neurological outcomes with conflicting findings (e.g., favorable neurological outcome was less likely, more likely, or no difference between obese and normal weight patients) (Considine et al. 2024, 100820; Considine et al. 2024; Bray et al. 2025, S34). Similarly conflicting findings were reported for short-term survival, survival to hospital discharge, survival from 1 to 5 years, and ROSC.

For studies reporting on CPR quality or techniques, there was no difference between obese and normal weight patients for shock success, percentage of shocks given in less than 2 minutes, and termination of ventricular fibrillation (VF) or ventricular tachycardia (VT), but one study (Jain et al. 2010, 490) reported longer CPR duration in obese patients with VF or VT when ROSC was not achieved.

The review summary noted the variability in clinical outcomes for adults and suggested worse outcomes in obese children, however the results do not suggest an urgent need to deviate from standard CPR protocols.

A good practice statement was made by ILCOR that standard CPR protocols should be used in obese patients (Considine et al. 2024; Bray et al. 2025,S24).

Insights and Implications

Despite the prevalence of obesity and severe obesity in the U.S., the studies identified for this review were limited, particularly for pediatric patients, and the impact of obesity on cardiac arrest patient outcomes were conflicting. There was no universal definition of obesity at the time of the scoping review, and “obese” was defined by each study, with wide variability across the studies. There was some evidence that CPR duration may be longer in obese adults, which may have implications for staffing and resources. Further research is needed to determine if the degree of obesity impacts CPR techniques, the use of mechanical CPR devices, extracorporeal membrane oxygenation, provider fatigue and other outcomes.

The Red Cross guideline is informed by this ILCOR review and good practice statement. Although there are no studies that address whether obesity influences CPR performance, when administering chest compressions to an obese individual, achieving the recommended depth of at least 2 inches (5 centimeters) may necessitate applying greater force than with individuals of normal weight. This increased exertion can lead to quicker fatigue for the person providing chest compressions, underscoring the importance of more frequent personnel rotations during CPR. These considerations should be integrated into CPR training programs to ensure healthcare professionals are prepared for such scenarios.

 

Firefighter-Down CPR

Last Full Review: American Red Cross Scientific Advisory Council 2023

Among firefighters, nearly half of all deaths are due to sudden cardiac events (Smith et al. 2013, 6). Most events occur while the firefighters are responding to calls and are associated with physical exertion during fire suppression activities (Smith et al. 2013, 6; Sen et al. 2016, 191; Soteriades et al. 2011, 202; Smith et al. 2016, 90). When responding to a structural fire or other hazard, firefighters wear full turnout gear. A self-contained breathing apparatus (SCBA) must also be worn when entering an immediately dangerous-to-life or dangerous-to-health atmosphere. This gear, with SCBA, can weigh up to 75 pounds or more, contributing to the physical stress and strain on the cardiovascular system.

With training, donning turnout gear and SCBA should take a total of 2 minutes, while doffing of gear may take significantly longer. When a firefighter wearing full turnout gear and SCBA loses consciousness, rescuers cannot readily assess for breathing and a pulse. In addition, because the oxygen cylinder is worn on the back, the firefighter cannot be placed in a full supine position for delivery of chest compressions. The turnout gear includes a helmet, faceplate, hood, jacket, harness, backplate, and SCBA tank and regulator—and all must be removed to perform high-quality cardiopulmonary resuscitation (CPR). However, attempts to remove turnout gear and SCBA can result in significant delays to providing CPR. This has led to suggested processes to rapidly extricate a firefighter who has collapsed and become unresponsive (“firefighter down”) followed by simultaneous compression-only CPR (CO-CPR) and expedited removal of turnout gear. This allows for the assessment of the collapsed firefighter and initiation of compression-ventilation CPR (CV-CPR) with automated external defibrillator (AED) use.

 

Evidence Summary

A 2023 American Red Cross Scientific Advisory Council scoping review sought to examine the evidence for the use of Firefighter Down-CPR (FD-CPR) or any other technique intended to expedite the early delivery of CPR to firefighters who, during strenuous firefighting activities, become unresponsive. Outcomes of interest included any clinical or physiological outcomes as well as evidence of harm. The literature search included both peer-reviewed and gray literature sources. Seven articles were identified, as well as multiple online videos. All videos demonstrated training in FD-CPR, Rapid Intervention Team CPR (RIT-CPR) or variations of CPR processes (Herbert 2014a; Herbert 2014b; Firefighters Support Foundation; DC Fire and EMS; Miami-Dade Fire Rescue). In general, these techniques begin following the extrication of an unresponsive firefighter to a safe location, followed by the initial delivery of chest compressions while using a coordinated and practiced team approach to remove turnout gear in under 30 seconds, as follows:

• For FD-CPR, the initial chest compressions begin after a first firefighter-rescuer pulls the unresponsive firefighter from behind to a safe position, then assumes a seated position with the unresponsive firefighter semi-reclined with their SCBA tank cradled between the outstretched legs of the seated rescuer. This provides a stable platform for chest compressions.
• Compression-only CPR is provided by a second rescuer after opening the chest clip of the SCBA while the firefighter supporting the unresponsive firefighter opens the SCBA bypass valve and removes the helmet, face mask, hood and gloves.
• A third rescuer unbuckles or unzips the turnout jacket, loosens the shoulder straps of the SCBA, and positions the arms of the unresponsive firefighter above their head.
• While the first (seated) firefighter-rescuer grasps the jacket and SCBA shoulder straps, the third and fourth rescuers grab the legs of the unresponsive firefighter and pull the firefighter down and out of their turnout jacket and SCBA.
• Assessment and initiation of conventional CV-CPR and AED use follows the removal of turnout gear. The entire process requires a well-practiced, coordinated team effort with at least three firefighter-rescuers.

 

The articles included in the scoping review provide the rationale for the use of FD-CPR as well as step-by-step instructions.

A single proof-of-concept simulation study (Beasley 2017) was identified and performed by the Bushfire & National Hazards Cooperative Research Centers program in Australia, which used high-fidelity manikins with video recording and time stamping capabilities, a biometric shirt, pre- and post- confidence and encoding surveys and decibel readings. Data collected with video time stamping included time-to-first compression, time-to-gear removal, time-to-first ventilation and time-to-AED placement. Manikin data included a compression score, ventilation score, hand placement, ventilation volume, hands-off-chest time, compression depth, chest recoil and total CPR score. Data was collected for single trials of a normal cardiac arrest CPR drill, a fire and rescue cardiac arrest CPR drill and a Firefighter-Down cardiac arrest drill. The study reported 15 seconds as the time-to-first compression for the FD-CPR drill, compared to 37 seconds as the time-to-first compression for the (standard) fire and rescue cardiac arrest drill, which equated to a 59% decrease in time to start CPR. Time-to-gear removal for the FD-CPR cardiac arrest drill was 21 seconds versus 45 seconds for the fire and rescue cardiac arrest drill. Other outcomes, such as time-to-AED placement and time-to-ventilation, were improved with the FD-CPR drill compared with the fire and rescue cardiac arrest drill. The CPR score, with higher scores reflecting higher-quality CPR, were higher in the FD-CPR drill than for the fire and rescue cardiac arrest drill, but still lower than for a normal cardiac arrest drill. Other CPR parameters reported for the FD-CPR cardiac arrest drill included 100% correct hand placement, compression depth over 5 centimeters, compression rate over 100 per minute and a 34% to 68% chest recoil.

One online article (Schwalbe 2017) was identified describing difficulties with the FD-CPR process in practice. Concerns included the difficulty with working around the rescuer providing CO-CPR while attempting to rapidly remove turnout gear, and the potential for not having three rescuers immediately available. It was also noted that there is uncertainty if the unresponsive firefighter is in cardiac arrest, or if they have had a syncopal episode due to heat exposure and dehydration. It is not possible to assess for ventilations in a firefighter wearing full turnout gear, and the assumption with FD-CPR is that an unresponsive firefighter in a strenuous firefighting event has suffered a cardiac arrest. A proposed variation on the process of providing early CPR is to remove the gear in 20 to 30 seconds with two rescuers, perform a rapid assessment and then render appropriate care, including CV-CPR, as indicated.

No case reports of successful use of FD-CPR or RIT-CPR (resuscitation following a search and rescue for a missing, injured or unaccounted for firefighter by a designated rapid intervention team) were identified in the scoping review, and no reports of harm from the delivery of CO-CPR to a person wearing a SCBA with or without back plate were identified. No reports were identified of CO-CPR use in an unresponsive firefighter who was subsequently found to not be in cardiac arrest. A previous International Liaison Committee on Resuscitation review (Olasveengen et al. 2020, S41) of harm from providing chest compressions to an unresponsive person subsequently found not to be in cardiac arrest reported a low incidence of injuries and concluded that the potential survival benefit of providing CPR to a person believed to be in cardiac arrest outweighs the risk of injury.

The review concludes that, to perform high-quality CV-CPR, the unresponsive firefighter must be extricated from the turnout gear and SCBA. Any technique that allows for the rapid and safe removal of this gear will allow for earlier delivery of CV-CPR. If that technique also incorporates early delivery of chest compressions (CO-CPR), this will further decrease any delay in starting CPR and the circulatory “no flow” time.

Insights and Implications

Firefighter-Down and RIT-CPR are intended to improve the odds of survival from cardiac arrest in firefighters wearing full turnout gear. The early provision of CPR is key to survival in cardiac arrest, but the need to extricate a downed firefighter from a dangerous environment inherently creates a delay in starting CPR. Beginning CO-CPR immediately after extrication to a safe location and simultaneously removing turnout gear in a rapid, coordinated fashion, allows earlier access to the downed firefighter for further assessment and delivery of CV-CPR and AED or defibrillator use.

Over the past decade, sudden cardiac arrest has accounted for 42% of all firefighter duty-related fatalities. A retrospective review of autopsy findings in one study of 285 firefighter cardiac fatalities reported that 80% had evidence at autopsy of coronary heart disease and increased heart size. The increased risk of cardiac arrest in firefighters is leading to efforts to manage individual cardiovascular risk factors and to limit body temperature and duty-related risks, such as limiting duration of exposure, initiating cooling to mitigate heat stress and ensuring adequate hydration. Novel methods of wireless monitoring of physiological parameters using noncontact electrodes embedded in fire suits are an area of research that in the future may allow earlier recognition of cardiac abnormalities requiring preemptive interventions.