Dispatcher-assisted compression-only cardiopulmonary resuscitation provides best quality cardiopulmonary resuscitation by laypersons: A randomised controlled single-blinded manikin trial

Enhancing the Chain of Survival: The Role of Smartphone Applications in Cardiopulmonary Resuscitation

This review explores the role of smartphone applications in providing real-time guidance for cardiopulmonary resuscitation (CPR) practices and highlights their potential to improve CPR quality among laypersons. A narrative literature review was conducted on the effectiveness of mobile CPR applications for smartphones. Studies published between 2014 and 2024 were included to ensure that new technological advances were examined. Our findings revealed that guided CPR applications significantly improve most critical parameters for efficacious resuscitation. Application users demonstrated that they achieved performance comparable to or even better than CPR-certified individuals. However, these tools have limitations, mostly related to familiarity, which may result in a delay in activating the application and, therefore, in initiating CPR. While smartphone applications are promising tools for enhancing bystander CPR, their integration into emergency medical response requires careful consideration. To fully take advantage of these applications, they should be incorporated into public health campaigns and standard CPR training. This would be even more successful if the application's functionality were standardized across different regions. Our research indicates that a combination of education and technology will likely play a major role in CPR training in the future, improving the efficacy and accessibility of life-saving measures. Smartphone applications could greatly improve the chain of survival in out-of-hospital cardiac arrest (OHCA) events. The design and accessibility of these applications as well as the integration of these applications with current emergency response frameworks should be the main areas of future research.

A randomized controlled simulation trial comparing video-assisted with telephone-assisted and unassisted cardiopulmonary resuscitation performed by non-healthcare university students

Our randomized controlled simulation study aimed to compare the CPR quality, time-related factors, attitude and self-assessment of non-healthcare university students (aged 18-25) compared video-assisted (V-CPR, n = 50) with telephone-assisted (T-CPR, n = 49) and unassisted (U-CPR, n = 48) CPR in a simulation setting. Regarding to chest compression depth, no difference was found between the three groups (p = 0.065): 41.8 mm, SD = 9.9 in the V-CPR; 35.9 mm, SD = 11.6 in the T-CPR; and 39.4 mm, SD = 15.6 in the U-CPR group. The mean chest compression rate was the best in the V-CPR group (100.9 min-1, SD = 17.1) which was superior to the T-CPR (82.4 min-1, SD = 35.4; p = 0.005), and the U-CPR (84.2 min-1, SD = 30.6; p = 0.013) groups. The overall proportion of correct hand position was the highest in the V-CPR group (48, 96%), compared to the T-CPR (28, 57.1%; p = 0.001), and the U-CPR (34, 70.8%; p = 0.001) groups. V-CPR led to a delay in the time to the first chest compression compared with the U-CPR group (77.5 s, SD = 19.2 vs. 31.3 s, SD = 13.3, p < 0.001). Although V-CPR technology holds the potential to improve overall CPR quality, the importance of appropriate chest compression depth should be emphasized in training for laypeople and dispatchers, as well. Our study was registered at ClinicalTrials.gov (NCT05639868, 06/12/2022).

Association of dispatcher-assisted cardiopulmonary resuscitation with initial shockable rhythm and survival after out-of-hospital cardiac arrest

BACKGROUND AND IMPORTANCE

Bystander cardiopulmonary resuscitation (CPR) and initial shockable rhythm are crucial predictors of survival after out-of-hospital cardiac arrest (OHCA). However, the relationship between dispatcher-assisted CPR (DA-CPR) and initial shockable rhythm is not completely elucidated.

OBJECTIVE

To examine the association of DA-CPR with initial shockable rhythm and outcomes.

DESIGN, SETTING AND PARTICIPANTS

This nationwide population-based observational study conducted in Japan included 59 688 patients with witnessed OHCA of cardiac origin after excluding those without bystander CPR. Patients were divided into DA-CPR (n = 42 709) and CPR without dispatcher assistance (unassisted CPR, n = 16 979) groups.

OUTCOME MEASURES AND ANALYSIS

The primary outcome measure was initial shockable rhythm, and secondary outcome measures were 1-month survival and neurologically intact survival. A Cox proportional hazards model adjusted for collapse-to-first-rhythm-analysis time and multivariable logistic regression models were used after propensity score (PS) matching to compare the incidence of initial shockable rhythm and outcomes, respectively.

MAIN RESULTS

Among all patients (mean age 76.7 years), the rates of initial shockable rhythm, 1-month survival and neurologically intact survival were 20.8, 10.7 and 7.0%, respectively. The incidence of initial shockable rhythm in the DA-CPR group (20.4%, 3462/16 979) was significantly higher than that in the unassisted CPR group (18.5%, 3133/16 979) after PS matching (P < 0.0001). However, no significant differences were found between the two groups with respect to the incidence of initial shockable rhythm in the Cox proportional hazards model [adjusted hazard ratio of DA-CPR for initial shockable rhythm compared with unassisted CPR, 0.99; 95% confidence interval (CI), 0.97-1.02, P = 0.56]. No significant differences were observed in the survival rates in the two groups after PS matching [10.8% (1833/16 979) vs. 10.3% (1752/16 979), P = 0.16] and neurologically intact survival rates [7.3% (1233/16 979) vs. 6.8% (1161/16 979), P = 0.13]. The multivariable logistic regression model showed no significant differences between the groups with regard to survival (adjusted odds ratio of DA-CPR compared with unassisted CPR: 1.00; 95% CI, 0.89-1.13, P = 0.97) and neurologically intact survival (adjusted odds ratio: 1.12; 95% CI, 0.98-1.29, P = 0.14).

CONCLUSION

DA-CPR after OHCA had the same independent association with the likelihood of initial shockable rhythm and 1-month meaningful outcome as unassisted CPR.

Effectiveness of a Dispatcher-Assisted Cardiopulmonary Resuscitation Program Developed by the Thailand National Institute of Emergency Medicine (NIEMS)

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is a life-threatening condition with an overall survival rate that generally does not exceed 10%. Several factors play essential roles in increasing survival among patients experiencing cardiac arrest outside the hospital. Previous studies have reported that implementing a dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) program increases bystander CPR, quality of chest compressions, and patient survival. This study aimed to assess the effectiveness of a DA-CPR program developed by the Thailand National Institute for Emergency Medicine (NIEMS).

METHODS

This was an experimental study using a manikin model. The participants comprised both health care providers and non-health care providers aged 18 to 60 years. They were randomly assigned to either the DA-CPR group or the uninstructed CPR (U-CPR) group and performed chest compressions on a manikin model for two minutes. The sequentially numbered, opaque, sealed envelope method was used for randomization in blocks of four with a ratio of 1:1.

RESULTS

There were 100 participants in this study (49 in the DA-CPR group and 51 in the U-CPR group). Time to initiate chest compressions was statistically significantly longer in the DA-CPR group than in the U-CPR group (85.82 [SD = 32.54] seconds versus 23.94 [SD = 16.70] seconds; P <.001). However, the CPR instruction did not translate into better performance or quality of chest compressions for the overall sample or for health care or non-health care providers.

CONCLUSION

Those in the CPR-trained group applied chest compressions (initiated CPR) more quickly than those who initiated CPR based upon dispatch-based CPR instructions.

Quality of dispatcher-assisted vs. automated external defibrillator-guided cardiopulmonary resuscitation: a randomised simulation trial

BACKGROUND

Quality of hands-only cardiopulmonary resuscitation (CPR) is an important determinant of resuscitation outcome for cardiac arrest patients cared for by lay rescuers. We designed a simulation trial to assess and compare the quality of CPR among untrained lay people under two different scenarios: automated external defibrillator (AED)-guided and dispatcher-assisted CPR.

PATIENTS AND METHODS

A simulation study was performed involving 42 volunteers selected by non-probabilistic sampling. Participants were randomized into two CPR simulation scenarios with a manikin: (A) AED-guided CPR and (T) dispatcher-assisted CPR. The quality of CPR was evaluated by metric monitoring of the chest compressions and timing of actions. Content analysis of the telephone instructions was performed by two independent researchers using a checklist.

RESULTS

CPR was started in 20 of the 21 cases in scenario A and in all cases in scenario T. In total, 12 053 chest compressions were applied, 57.6% corresponding to scenario A. The proportion of compressions that were of an adequate depth was low in both cases, 15.3% in scenario A vs. 31.7% in scenario T (P < 0.001), while complete chest recoil was allowed in 66 and 72% (P < 0.001) of compressions, respectively. The AED advised to shock 91 times, and shocks were delivered in all cases.

CONCLUSIONS

Although guided CPR helps untrained people to initiate resuscitation manoeuvres, the quality of CPR was poor in both groups. Telephone guidance improved the proportion of compressions that achieved adequate chest compression and recoil but did not optimise the compression rate.

The inefficiency of ventilation in basic resuscitation. Should we improve mouth-to-mouth ventilation training of nursing students?

OBJECTIVE

To analyse the differences in the quality of the basic cardiopulmonary resuscitation (CPR) between the algorithms of compressions with rescue ventilation (CPR [30:2]) and chest compressions only (CPR [C/O]). In addition, the specific objective was to study the effectiveness of the physical manoeuvre of mouth-to-mouth ventilations performed by nursing students after the completion of a simulation training program in Basic Life Support (BLS) standardized in the study plan approved for the Nursing Degree at a Spanish university.

RESEARCH METHODOLOGY

analytical, quasi-experimental, cross-sectional study with clinical simulation of 114 students enrolled in the third year of the Nursing Degree.

RESULTS

the mean depth of chest compressions was 47.6 mm (SD 9.5) for CPR [30:2] and 45 mm (SD 8.8) when CPR [C/O] was performed (t = 5.39, p < 0.0001, CI95% 1.69-3.65). The compressions with complete chest re-expansion were 106 (SD 55) for CPR [30:2] and 138 (SD 85) for CPR [C/O] [t = -4.75, p < 0.0001, CI95% -44.6 - (-18.4)]. Of the participants, 28.1% correctly ventilated with the head-tilt/chin-lift manoeuvre (Fisher: p < 0.0001).

CONCLUSIONS

As a whole, CPR with only chest compressions offers great advantages with respect to standard CPR, minimizing interruptions in compressions, maintaining coronary and cerebral perfusion and thus increasing the likelihood of return of spontaneous circulation. The problem of rescuers fatigue could be reduced with a greater number of relays between rescuers. We believe that is important to improve the acquisition of competencies in the management of the airway and the ventilation devices (such as the bag-valve mask).

The effect of 10-min dispatch-assisted cardiopulmonary resuscitation training: a randomized simulation pilot study

Background

Immediate bystander cardiopulmonary resuscitation (CPR) is essential for survival from sudden cardiac arrest (CA). Current CPR guidelines recommend that dispatchers assist lay rescuers performing CPR (dispatch-assisted CPR (DACPR)), which can double the frequency of bystander CPR. Laypersons, however, are not familiar with receiving CPR instructions from dispatchers. DACPR training can be beneficial for lay rescuers, but this has not yet been validated. The aim of this study was to determine the effectiveness of simple DACPR training for lay rescuers.

Methods

We conducted a DACPR simulation pilot study. Participants who were non-health care professionals with no CPR training within 1 year prior to this study were recruited from Nara Medical University Hospital. The participants were randomly assigned to one of the two 90-min adult basic life support (BLS) training course groups: DACPR group (standard adult BLS training plus an additional 10-min DACPR training) or Standard group (standard adult BLS training only). In the DACPR group, participants practiced DACPR through role-playing of a dispatcher and an emergency caller. Six months after the training, all subjects were asked to perform a 2-min CPR simulation under instructions given by off-duty dispatchers.

Results

Out of the 66 participants, 59 completed the simulation (30 from the DACPR group and 29 from the Standard group). The CPR quality was similar between the two groups. However, the median time interval between call receipt and the first dispatch-assisted compression was faster in the DACPR group (108 s vs 129 s, p = 0.042).

Conclusions

This brief DACPR training in addition to standard CPR training can result in a modest improvement in the time to initiate CPR. Future studies are now required to examine the effect of DACPR training on survival of sudden CA.

Using a Mobile Phone Application Versus Telephone Assistance During Cardiopulmonary Resuscitation: A Randomized Comparative Study

INTRODUCTION

In recent years, the way CPR instructions are given has changed because of the development of new technology that allows bystanders who witness a cardiac arrest to be guided in performing CPR. This study aimed to compare the effectiveness of using a mobile phone application (app) versus telephone operator assistance in performing cardiopulmonary resuscitation (CPR) techniques in simulated settings.

METHODS

A comparative study was performed with 2 intervention groups: (1) mobile phone app and (2) telephone assistance. A total of 128 students participated and were distributed randomly into each intervention group. A CPR observation checklist and standard CPR quality parameter measurements were used for data collection.

RESULTS

The group that used the app obtained better results than the group that had telephone assistance on 5 items during CPR observation: checking if the area is secure (X²(1) = 26.81; P < 0.05), asking for help (X²(1) = 66.07; P < 0.05), opening of airways (X²(1) = 12.03; P < 0.05), checking for breathing (X²(1) = 6.10; P < 0.05), and contacting emergency services (X²(1) = 12.41; P < 0.05). Regarding the skill level of CPR, no statistically significant differences were found when comparing the 2 intervention groups (X²(1) = 0.91; P = 0.33). As for the parameters measured, there were only statistically significant differences found in the item compression fraction (U = 1,593.00; Z = -2.16; P < 0.05), with the group that used the app obtaining better results.

DISCUSSION

Better outcomes were observed in recognizing if the area was safe, asking for help, opening up the airways, checking for breathing, and calling emergency services in the mobile phone app group. However, the results indicated that there were no differences in the CPR parameters, except compression fraction, when the app was used as opposed to being guided by telephone.

Verbal Motivation vs. Digital Real-Time Feedback during Cardiopulmonary Resuscitation: Comparing Bystander CPR Quality in a Randomized and Controlled Manikin Study of Simulated Cardiac Arrest

OBJECTIVE

The use of smartphone applications increases bystander CPR quality as well as the use of telephone CPR protocols. The present prospective, randomized, controlled manikin trial analyses the effects of a smartphone application (PocketCPR©) on CPR quality in a bystander CPR scenario compared to a dispatcher-assisted telephone CPR with the additional use of a metronome and verbal motivation. Methods: 150 laypersons were included to perform 8-minute CPR on a manikin. Volunteers were randomly assigned to one of three groups: (1) dispatcher-assisted telephone CPR (telephone-group), (2) dispatcher-assisted telephone CPR combined with the smartphone-application (telephone + app-group) and (3) dispatcher-assisted telephone CPR with additional verbal motivation ("push harder, release completely," every 20 seconds, starting after 60 seconds) and a metronome with 100 min^-1 (telephone + motivation-group). Results: Median compression depth did not differ significantly between the study groups (p = 0.051). However, in the post hoc analysis median compression depth in the telephone + motivation-group was significantly elevated compared to the telephone + app-group (59 mm [IQR 47-67 mm] vs. 51 mm [IQR 46-57 mm]; p = 0.025). The median number of superficial compressions was significantly reduced in the telephone + motivation-group compared to the telephone + app-group (70 [IQR 3-362] vs. 349 [IQR 88-538]; p = 0.004), but not compared to the telephone-group (91 [IQR 4-449]; p = 0.707). In contrast to the other study groups, median compression depth of the telephone + motivation-group increased over time. Chest compressions with correct depth were found significantly more often in the telephone + app-group compared to the other study groups (p = 0.011). Median compression rate in the telephone + app-group was significantly elevated (108 min^-1 [IQR 96-119 min^-1]) compared to the telephone-group (78 min^-1 [IQR 56-106 min^-1]; p < 0.001) and the telephone + motivation-group (99 min^-1 [IQR 91-101 min^-1]; p < 0.001). Conclusions: The use of a smartphone application as well as verbal motivation by a dispatcher during telephone CPR leads to higher CPR quality levels compared to standard telephone CPR. Thereby, the use of the smartphone application mainly shows an increase in compression rate, while increased compression rate with simultaneously increased compression depth was only apparent in the telephone + motivation-group.

Effects of dispatcher-initiated telephone cardiopulmonary resuscitation after out-of-hospital cardiac arrest: A nationwide, population-based, cohort study

AIM

This study aimed to investigate the effects of dispatcher-initiated telephone cardiopulmonary resuscitation (TCPR) in Japan using a nationwide population-based registry.

METHODS

Adult Japanese patients with out-of-hospital cardiac arrest (OHCA; n = 582,483, age ≥18 years) were selected from a nationwide Utstein-style database (2010-2016) and divided into 3 groups: no bystander CPR (NCPR) before emergency medical service arrival (n = 448,606), bystander-initiated CPR (BCPR) performed without assistance (n = 46,964), and TCPR (n = 86,913). The primary outcome was a favourable neurological outcome 1 month after OHCA.

RESULTS

After adjusting for potential confounders, and relative to the NCPR group, significantly better 1-month neurological outcomes were observed in the BCPR group (odds ratio: 2.25, 95% confidence interval: 2.15-2.36; P < 0.001) and in the TCPR group (odds ratio: 1.30, 95% confidence interval: 1.24-1.36; P < 0.001). The collapse-to-CPR time was independently associated with the 1-month outcomes, with a rate of <1% for 1-month favourable neurological outcomes if CPR was initiated >5 min after the collapse.

CONCLUSION

Patients who received TCPR had significantly better outcomes than those who did not receive CPR. However, the TCPR outcomes were less favourable than those in the BCPR group. Better protocol development and enhanced education are needed to improve dispatcher instructions in Japan, which may help lessen the gap between the BCPR and TCPR outcomes and further improve the outcomes after OHCA.

Effect of using a home-bed mattress on bystander chest compression during out-of-hospital cardiac arrest

Background:

Bystander cardiopulmonary resuscitation is a key component of life-saving after an out-of-hospital cardiac arrest. In the pre-arrival instructions for out-of-hospital cardiac arrest, it is recommended that the patient be laid on a flat floor. However, the most common reason for not performing cardiopulmonary resuscitation is that the bystander could not move the patient.

Objectives:

This study aim to investigate the effects of using a home-bed mattress on the quality of chest compression.

Methods:

In this prospective, randomized study, chest compression without ventilation was performed for 4 min on a Resusci Anne manikin placed on a flat floor or on three types of home-bed mattresses (hard, medium and soft). Chest compression depth, chest compression rate and chest recoil were measured from the manikin with the Laerdal PC Skill Reporting System, and changes in chest compression quality using the four different surfaces were compared.

Results:

Thirty participants were enrolled to perform chest compression. There was no significant difference in chest compression depth and depth accuracy between the four surfaces. The median chest compression rates were 108.1 ± 8.5, 107.0 ± 8.3, 103.3 ± 8.9 and 98.3 ± 7.9 compressions/min ( p < 0.001) for the flat floor, hard-, medium-, and soft-firmness mattresses, respectively. Moreover, there was no a significant difference in chest recoil accuracy.

Conclusion:

Using a home-bed mattress did not decrease the chest compression quality, except chest compression rate of soft-firmness mattress. Thus, it may be effective to initiate chest compression on a home-bed mattress if the bystander cannot move the patient to the floor.

The use of dispatcher assistance in improving the quality of cardiopulmonary resuscitation: A randomised controlled trial

AIMS

The introduction of dispatcher assistance (DA) services has led to increased bystander cardiopulmonary resuscitation (CPR) participation rates. However, the extent to which DA improves CPR quality remains unclear. This study aimed to evaluate the efficacy of DA in improving CPR quality among healthcare professionals and laypersons within a multi-ethnic Southeast Asian population.

METHODS

A parallel, randomised controlled, open label trial was performed. Four hundred and twelve participants were recruited via convenience sampling in a public location. In a simulated cardiac-arrest scenario, the participants were randomised to perform CPR with DA over the phone (DA+) or CPR without DA (DA-). The ratio of participant assignment to DA+ and DA- was 1:1. The primary outcomes were CPR compression depth, compression rate, no-flow time, complete release of pressure between compressions, and hand location. The assessment involved CPR manikins and human assessors.

RESULTS

A larger proportion of participants in DA + achieved the correct compression rate (34.3% vs 18.1%, p < 0.001). There was no difference in the other primary outcomes. A subgroup analysis revealed that healthcare professionals in DA+ had a higher proportion of correct hand location compared to those in DA- (82.1% vs. 53.5%, p < 0.05). There was no significant difference in CPR quality among laypersons with valid CPR certification regardless of whether they received DA.

CONCLUSION

DA should be provided to laypersons without valid CPR certification, as well as healthcare professionals. The identification of gaps in the current DA protocol highlights areas where specific changes can be made to improve CPR quality.

Using a smartphone application (PocketCPR) to determine CPR quality in a bystander CPR scenario - A manikin trial

PURPOSE OF THE STUDY

Feedback devices and dispatcher assistance increase CPR quality in bystander resuscitation. Yet, there is no data comparing both approaches with uninstructed CPR. The present prospective, randomized, controlled, manikin trial aims to determine the effects of the use of a smartphone application (PocketCPR) on CPR quality in a bystander CPR scenario compared to dispatcher-assisted telephone CPR and uninstructed CPR.

METHODS

100 laypersons were included to perform 8-min CPR on a manikin. Volunteers were randomly assigned to one of four groups: (1) uninstructed CPR (uninstructed group), (2) dispatcher-assisted telephone CPR (telephone-group), (3) guidance and feedback through a smartphone application (app-group) and (4) dispatcher-assisted telephone CPR combined with the smartphone-app (telephone + app-group).

RESULTS AND DISCUSSION

There was no significant difference in the time to first compression between the uninstructed and the app-group (p = 0.052), likewise between the telephone- and the telephone + app-group (p = 0.193). The no-flow-time of the uninstructed group was significantly longer compared to all other groups (p < 0.001). Median compression rate was significantly higher and within the recommended range in the app- and the telephone + app-group. There was no significant difference regarding correct compression depth between the four groups. Correct hand position and complete thorax release was found significantly more frequently in groups with smartphone-app support.

CONCLUSIONS

Feedback by a smartphone application can improve bystander CPR quality in terms of no-flow-time, compression rate, correct hand position, thorax release and does not delay CPR onset. However, the use of a smartphone application does not improve compression depth significantly.

Interventions to improve the quality of bystander cardiopulmonary resuscitation: A systematic review

Background

Performing high-quality bystander cardiopulmonary resuscitation (CPR) improves the clinical outcomes of victims with sudden cardiac arrest. Thus far, no systematic review has been performed to identify interventions associated with improved bystander CPR quality.

Methods

We searched Ovid MEDLINE, Ovid EMBASE, EBSCO CINAHL, Ovid PsycInfo, Thomson Reuters SCI-EXPANDED, and the Cochrane Central Register of Controlled Trials to retrieve studies published from 1 January 1966 to 5 October 2018 associated with interventions that could improve the quality of bystander CPR. Data regarding participant characteristics, interventions, and design and outcomes of included studies were extracted.

Results

Of the initially identified 2,703 studies, 42 were included. Of these, 32 were randomized controlled trials. Participants included adults, high school students, and university students with non-medical professional majors. Interventions improving bystander CPR quality included telephone dispatcher-assisted CPR (DA-CPR) with simplified or more concrete instructions, compression-only CPR, and other on-scene interventions, such as four-hand CPR for elderly rescuers, kneel on opposite sides for two-person CPR, and CPR with heels for a tired rescuer. Devices providing real-time feedback and mobile devices containing CPR applications or software were also found to be beneficial in improving the quality of bystander CPR. However, using mobile devices for improving CPR quality or for assisting DA-CPR might cause rescuers to delay starting CPR.

Conclusions

To further improve the clinical outcomes of victims with cardiac arrest, these effective interventions may be included in the guidelines for bystander CPR.

In-flight cardiac arrest and in-flight cardiopulmonary resuscitation during commercial air travel: consensus statement and supplementary treatment guideline from the German Society of Aerospace Medicine (DGLRM)

By the end of the year 2016, approximately 3 billion people worldwide travelled by commercial air transport. Between 1 out of 14,000 and 1 out of 50,000 passengers will experience acute medical problems/emergencies during a flight (i.e., in-flight medical emergency). Cardiac arrest accounts for 0.3% of all in-flight medical emergencies. So far, no specific guideline exists for the management and treatment of in-flight cardiac arrest (IFCA). A task force with clinical and investigational expertise in aviation, aviation medicine, and emergency medicine was created to develop a consensus based on scientific evidence and compiled a guideline for the management and treatment of in-flight cardiac arrests. Using the GRADE, RAND, and DELPHI methods, a systematic literature search was performed in PubMed. Specific recommendations have been developed for the treatment of IFCA. A total of 29 specific recommendations for the treatment and management of in-flight cardiac arrests were generated. The main recommendations included emergency equipments as well as communication of the emergency. Training of the crew is of utmost importance, and should ideally have a focus on CPR in aircraft. The decision for a diversion should be considered very carefully.