Mechanical Cardiopulmonary Resuscitation Devices: Evidence Synthesis with an Umbrella Review.

AIM: Sudden cardiac arrest is a significant cause of death worldwide. Good quality cardiopulmonary resuscitation increases patients' survival. Manual cardiopulmonary resuscitation is often ineffective as rescuers may experience physical and mental fatigue. Mechanical cardiopulmonary resuscitation devices are designed to address this issue, providing an automated approach for high-quality resuscitation. In the present comprehensive umbrella review we summarize current evidence on mechanical devices. METHODS: We searched systematic reviews on mechanical devices in MEDLINE/PubMed. Effect estimates were obtained from original reports, including 95% confidence intervals and p values, when applicable and available, focusing on return of spontaneous circulation, survival to discharge or 30 days, survival with good neurological outcome, and resuscitation-related injuries. RESULTS: From 21 potentially pertinent publications, we shortlisted 10 reviews, each including between 5 and 22 studies. AutoPulse, LUCAS, and LUCAS-2 were among the investigated devices. Most reviews concluded toward mechanical devices being similar or better than manual resuscitation for return of spontaneous circulation and 30-days survival. Regarding survival with good neurological function, some reviews lacked data, while the remaining ones reported similar results or worse outcomes in patients undergoing mechanical resuscitation. Focusing on resuscitation-related injuries, data were limited or conflicting with one review reporting higher rates of injuries with mechanical devices, and two others suggesting similar outcomes. CONCLUSIONS: Manual and mechanical cardiopulmonary resuscitation appear to be similar in terms of return of spontaneous circulation and short-term survival. Mechanical devices appear to be associated with higher resuscitation-related injuries, while there are conflicting data in terms of survival with good neurological outcomes. A comprehensive and large dedicated randomized trial is urgently needed.

The effect of standalone audio-visual feedback devices on the quality of chest compressions during laypersons' cardiopulmonary resuscitation training: a systematic review and meta-analysis.

AIMS: Individual studies that investigated the effect of standalone audio-visual feedback (AVF) devices during laypersons' cardiopulmonary resuscitation (CPR) training have yielded conflicting results. This review aimed to evaluate the effect of standalone AVF devices on the quality of chest compressions during laypersons' CPR training. METHOD AND RESULT: Randomized controlled trials of simulation studies recruiting participants without actual patient CPR experience were included. The intervention evaluated was the quality of chest compressions with standalone AVF devices vs. without AVF devices. Databases, such as PubMed, Cochrane Central, Embase, Cumulative Index to Nursing & Allied Health Literature (CINAHL), Web of Science, and PsycINFO, were searched from January 2010 to January 2022. The risk of bias was assessed using the Cochrane risk of bias tool. A meta-analysis alongside a narrative synthesis was used for examining the effect of standalone AVF devices.Sixteen studies were selected for this systematic review. A meta-analysis revealed an increased compression depth of 2.22 mm [95% CI (Confidence Interval), 0.88-3.55, P = 0.001] when participants performed CPR using the feedback devices. Besides, AVF devices enabled laypersons to deliver compression rates closer to the recommended range of 100-120 per min. No improvement was noted in chest recoil and hand positioning when participants used standalone AVF devices. CONCLUSION: The quality of the included studies was variable, and different standalone AVF devices were used. Standalone AVF devices were instrumental in guiding laypersons to deliver deeper compressions without compromising the quality of compression rates. However, the devices did not improve the quality of chest recoil and placement of the hands. REGISTRATION: PROSPERO: CRD42020205754.

Optimal chest compression position for cardiopulmonary resuscitation determined by computed tomography image: retrospective cross-sectional analysis.

The objective of this study was to determine the height of optimal hand position for chest compression during adult cardiopulmonary resuscitation (CPR) from the tip of the sternal xiphoid process (TOX) along with the relative heights of the left ventricular outflow tract (LVOT) and abdominal organs among the Thai population. The retrospective cross-sectional study was conducted through a review of medical records and contrast-enhanced chest computed tomography. The total of 204 Thai patients without obvious chest deformity at Ramathibodi Hospital from January to June 2018 was included as part of a multi-regional study. The heights of the level of maximal LV width (LVmax), LOVT, top of liver and stomach with respect to TOX were measured on midline sagittal image. Mean age and body mass index (BMI) were 59.5 years and 23.9 kg/m2, respectively. One hundred and one subjects (49.5%) had pulmonary diseases. Mean height of the LVmax from TOX was 37.7 mm, corresponding to 20% of the sternal length (SL) in the inspiration arm raised position (IAR). The adjusted height of LVmax from TOX in the expiration arm-down position (EAD) was 89.7 mm (48% of SL). The inter-nipple line was at 84.5 mm (45.1% of SL) from TOX on IAR. Among 178 and 109 subjects whose uppermost part of the liver and stomach were above TOX, 80.4% and 94.5% were located within the lower half of the sternum, respectively. The adjusted optimal hand position for chest compression during CPR was at approximately 89.7 mm from TOX in EAD (48% of SL). The hand position at the upper part of the lower half of the sternum is closest to the adjusted LVmax and has a better chance to avoid compression of intraabdominal organs.Trial registration This trial was retrospectively registered on 2 February 2023 in the Thai Clinical Trial Registry, identification number TCTR 20230202006.

Association of Real-Time Feedback and Cardiopulmonary-Resuscitation Quality Delivered by Ambulance Personnel for Out-of-Hospital Cardiac Arrest.

Background High-quality cardiopulmonary resuscitation (CPR) is associated with improved survival from out-of-hospital cardiac arrest and includes chest compression depth, chest compression rate, and chest compression fraction within international guideline recommendations. Previous studies have demonstrated divergent results of real-time feedback on CPR performance and patient outcomes. This study investigated the association between emergency medical service CPR quality and real-time CPR feedback for out-of-hospital cardiac arrest. Methods and Results This study collected out-of-hospital cardiac arrest data within the Capital Region of Denmark and compared CPR quality delivered by ambulance personnel. Data were collected in 2 consecutive phases from October 2018 to February 2020. Median chest compression depth was 6.0 cm (no feedback) and 5.9 cm (real-time feedback) (P=0.852). Corresponding proportion of guideline-compliant chest compressions for depth was 16.6% and 28.7%, respectively (P<0.001). Median chest compression rate per minute was 111 and 109 (P<0.001), respectively. Corresponding guideline adherence proportion for compression rate was 65.4% compared with 80.4% (P<0.001), respectively. Chest compression fraction was 78.9% compared with 81.9% (P<0.001), respectively. The combination of guideline-compliant chest compression depth and chest compression rate simultaneously was 8.5% (no feedback) versus 18.8% (feedback) (P<0.001). Improvements were not significant for return of spontaneous circulation (odds ratio [OR], 1.08 [95% CI, 0.84-1.39]), sustained return of spontaneous circulation (OR, 1.00 [95% CI, 0.77-1.31]), or survival to hospital discharge (OR, 0.91 [95% CI, 0.64-1.30]). Conclusions Real-time feedback was associated with improved guideline compliance for chest compression depth, rate, and fraction but not return of spontaneous circulation, sustained return of spontaneous circulation, or survival to hospital discharge. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04152252.

Using computed tomography to evaluate proper chest compression depth for cardiopulmonary resuscitation in Thai population: A retrospective cross-sectional study.

INTRODUCTION: The effectiveness of cardiopulmonary resuscitation is determined by appropriate chest compression depth and rate. The American Heart Association recommended CC depth at 5-6 cm to indicate proper cardiac output during cardiac arrest. However, many studies showed the differences in the body builds between Caucasians and Asians. Therefore, this study aimed to determine heart compression fraction (HCF) in the Thai population by using contrast-enhanced computed tomography (CT) scan of the chest and a mathematical model. MATERIALS AND METHODS: Consecutive contrast-enhanced CT scans of the chest performed at Ramathibodi Hospital were retrospectively reviewed from January to March 2018 by two independent radiologists. Patients' characteristics, including gender, age, weight, height, and pre-existing diseases, were recorded, and the chest parameters were measured from a CT scan. The heart compression fraction (HCF) was subsequently calculated. RESULTS: Of 306 subjects, there were 139 (45.4%) males, 148 (47.4%) lung diseases and 10 (3.3%) heart diseases. Mean age and BMI were 60.4 years old and 23.8 kg/m2, respectively. Chest diameter, heart diameter, and non-cardiac soft tissue were significantly smaller in females compared to males. Mean (SD) HCF proportional with 50 mm and 60 mm depth were 38.3% (13.3%) and 50% (14.3%), respectively. There were significant differences of HCF proportional by 50 mm and 60 mm depth between men and women (33.2% vs 42.6% and 44% vs 54.9%, respectively (P<0.001)). In addition, a decrease in HCF was significantly observed among higher BMI groups. CONCLUSION: The CT scan and mathematical model showed that 38% and 50% HCF proportions were generated by 50 mm and 60 mm CC depth. HCF proportions were significantly different between genders and among BMI groups. The recommended depth of 5-6 cm is likely to provide sufficient CC depth in the population of Thailand.

Haemodynamic changes with varying chest compression rates in asphyxiated piglets.

BACKGROUND: Current neonatal resuscitation guidelines recommend that chest compressions (CCs) be delivered at a rate of 90/min. The aim of the study was to investigate the haemodynamic effects of different CC rates in a neonatal piglet model. METHODS: Six asphyxiated piglets were randomised to CC with rates of 60/min, 90/min, 120/min, 150/min and 180/min for 1 min at each rate. CCs superimposed with sustained inflations were performed with an automated CC machine. RESULTS: Six newborn piglets (age 0-3 days, weight 2.0-2.3 kg) were included in the study. Overall, there was a gradual increase in stroke volume, minimum and maximum rate of left ventricle pressure change (dp/dtmin and dp/dtmax), and carotid blood flow until CC rate of 150/min, with a level-off effect at a CC rate of 180/min. However, cardiac output continued to increase with the highest being at a CC rate of 180/min. CONCLUSION: Rate of CC was associated with changes in haemodynamic parameters during cardiopulmonary resuscitation. CC rate of 150-180/min during CC resulted in the highest cardiac output and arterial blood pressure. TRIAL REGISTRATION NUMBER: Preclincialtrials.eu PCTE0000249.

Comparison of two infant cardiopulmonary resuscitation techniques explained by phone in a non-health professionals' population: Two-thumbs encircling hand technique vs. two-fingers technique, a randomised crossover study in a simulation environment.

BACKGROUND: Paediatric out-of-hospital cardiac arrest (OHCA) is the reason for an emergency call in approximately 8/100,000 person-years. Improvement of OHCA resuscitation needs a quality chain of survival and a rapid start of resuscitation. The aim of this study was to compare the efficacy of two resuscitation techniques provided on a mannequin, the two-fingers technique (TFT) and the two-thumbs encircling hand technique (TTHT), explained by a trained emergency call responder on the phone in a population of non-health professionals. METHODS: We conducted a randomised crossover study in the simulation lab of a University Hospital. The participants included in the study were non-health professional volunteers of legal age. The participants were assigned (1:1 ratio) to two groups: group A: TFT then TTHT, group B: TTHT then TFT. Scenario and techniques were discovered during the evaluation. RESULTS: Thirty-five volunteers were randomised before the sessions and 33 ultimately came to the simulation lab. We found a better median QCPR global score during TTHT sessions than during TFT sessions (74 vs. 59, P = 0.046). Linear mixed models showed that the TTHT method was the only variable associated with a better QCPR global score [model 1: ß = 14.3; 95% confidence interval (CI), 2.4-26.2; model 2: ß = 14.5; 95% CI, 2.5-26.6]. CONCLUSION: Our study showed the superiority of TTHT for infant CPR performed by non-health professionals when an emergency call responder advised them over the phone. It seemed to be the best technique for a solo rescuer regardless of previous training.

Severe Vertebral Body Fracture-Dislocation as a Result of Chest Compressions: A Case Report.

BACKGROUND: Although high-quality chest compressions are an essential, lifesaving component of cardiopulmonary resuscitation, injuries are common with both manual and mechanical chest compressions. CASE REPORT: We discuss the case of a 77-year-old woman who sustained thoracic vertebral fractures after cardiopulmonary resuscitation involving both manual and mechanical chest compressions. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Routine post-cardiac arrest care should include evaluation for chest compression-related injury. If a patient has back pain, focal vertebral tenderness, or paraplegia after chest compressions, imaging to evaluate for vertebral fracture should be performed. If unable to assess for back pain or tenderness, consider imaging to evaluate for vertebral fracture in patients with kyphosis or osteopenia, as these patients are at higher risk for chest compression vertebral injury.

Open chest selective aortic arch perfusion vs open cardiac massage as a means of perfusion during in exsanguination cardiac arrest: a comparison of coronary hemodynamics in swine.

AIM: To describe and compare the aortic-right atrial pressure (AoP-RAP) gradients and mean coronary perfusion pressures (CPPs) generated during open chest selective aortic arch perfusion (OCSAAP) with those generated during open cardiac massage (OCM) in hypovolemic swine. METHODS: Ten male Hanford swine utilized in a prior poly-trauma study were included in the study. Animals were rendered hypovolemic via a 30% volume bleed. Upon confirmation of death, animals underwent immediate clamshell thoracotomy and aortic cross-clamping followed by 5 min of OCM. A catheter suitable for OCSAAP was then inserted into the aorta and animals underwent 1 min of OCSAAP at a rate of 10 mL/kg/min. Aortic and right atrial pressures were recorded continuously using solid-state blood pressure catheters. Representative 10-s intervals from each resuscitation method were extracted. Hemodynamic parameters including AoP-RAP gradients and CPPs were calculated and compared. RESULTS: At baseline, time from death to intervention was significantly shorter for OCM. However, mean CPPs and AoP-RAP gradients were significantly higher in animals undergoing OCSAAP. 98% of OCSAAP segments had a mean CPP > 15, compared to 35% of OCM intervals. While OCM had a significant negative correlation between time to intervention and maximum CPP, this correlation was not significant for OCSAAP. CONCLUSION: OCSAAP generates favorable and potentially time-resistant pressure gradients when compared to those generated by OCM. Further investigation of the technique of OCSAAP is warranted, as it may have potential utility as a therapy during resuscitative thoracotomy (RT).

Chest compression fraction calculation: A new, automated, robust method to identify periods of chest compressions from defibrillator data - Tested in Zoll X Series.

AIM: To introduce and evaluate a new, open-source algorithm to detect chest compression periods automatically by the rhythmic, high amplitude signals from an accelerometer, without processing single chest compression events, and to consecutively calculate the chest compression fraction (CCF). METHODS: A consecutive sample of defibrillator records from the German Resuscitation Registry was obtained and manually annotated in consensus as ground truth. Chest compression periods were determined by different automatic approaches, including the new algorithm. The diagnostic performance of these approaches was assessed. Further, using the different approaches in conjunction with different granularities of manual annotation, several CCF versions were calculated and compared by intraclass correlation coefficient (ICC). RESULTS: 131 defibrillator recordings with a total duration of 5755 minutes were analysed. The new algorithm had a sensitivity of 99.39 (95% CI 99.38, 99.41)% and specificity of 99.17 (95% CI 99.15; 99.18)% to detect chest compressions at any given timepoint. The ICC compared to ground truth was 0.998 for the new algorithm and 0.999 for manual annotation, while the ICC of the proposed algorithm compared to the proprietary software was 0.978. The time required for manual annotation to calculate CCF was reduced by 70.48 (22.55, [94.35, 14.45])%. CONCLUSION: The proposed algorithm reliably detects chest compressions in defibrillator recordings. It can markedly reduce the workload for manual annotation, which may facilitate uniform reporting of measured quality of cardiopulmonary resuscitation. The algorithm is made freely available and may be used in big data analysis and machine learning approaches.

Hands-on defibrillation with safety drapes: Analysis of compressions and an alternate current pathway.

BACKGROUND: Hands-on defibrillation (HOD) could theoretically improve the efficacy of cardiopulmonary resuscitation (CPR) though a few mechanisms. Polyethylene drapes could potentially facilitate safe HOD, but questions remain about the effects of CPR on polyethylene's conductance and the magnitude of current looping through rescuers' arms in contact with patients. METHODS: This study measured the leakage current through 2 mil (0.002 in.) polyethylene through two different current pathways before and after 30 min of continuous compressions on a CPR mannequin. The two pathways analyzed were the standardized IEC (International Electrotechnical Commission) leakage current analysis and a setup analyzing a current pathway looping through a rescuer's arms and returning to the patient. First, ten measurements involving the two pathways were obtained on a single polyethylene drape. 30 min of continuous compressions were applied to the drape on a CPR mannequin after which the ten measurements were repeated. RESULTS: Twenty patients undergoing elective cardioversion for atrial fibrillation (18/20) or atrial flutter (2/20) at Emory University Hospital underwent analysis all receiving 200 J shocks (age 38-101, 35% female). Through the IEC measurement method the peak leakage current mean was 0.70 +/- 0.02 mA before compressions and 0.59 +/- 0.19 mA after compressions. Only three of the ten measurements assessing current passing through a rescuer's arms had detectable current and each was of low magnitude. All measurements were well below the maximum IEC recommendations of 3.5 mA RMS and 5.0 mA peak. CONCLUSIONS: Polyethylene may facilitate safe HOD even after long durations of compressions. Current looping through a rescuer's arms is likely of insignificant magnitude.

Efficacy of cardiopulmonary resuscitation performance while wearing a powered air-purifying respirator.

BACKGROUND: The use of personal protective equipment for respiratory infection control during cardiopulmonary resuscitation (CPR) is a physical burden to healthcare providers. The duration for which CPR quality according to recommended guidelines can be maintained under these circumstances is important. We investigated whether a 2-min shift was appropriate for chest compression and determined the duration for which chest compression was maintained in accordance with the recommended guidelines while wearing personal protective equipment. METHODS: This prospective crossover simulation study was performed at a single center from September 2020 to October 2020. Five indicators of CPR quality were measured during the first and second sessions of the study period. All participants wore a Level D powered air-purifying respirator (PAPR), and the experiment was conducted using a Resusci Anne manikin, which can measure the quality of chest compressions. Each participant conducted two sessions. In Session 1, the sequence of 2 min of chest compressions, followed by a 2-min rest, was repeated twice; in Session 2, the sequence of 1-min chest compressions followed by a 1-min rest was repeated four times. RESULTS: All 34 participants completed the study. The sufficiently deep compression rate was 65.9 ± 31.1% in the 1-min shift group and 61.5 ± 30.5% in the 2-min shift group. The mean compression depth was 52.8 ± 4.3 mm in the 1-min shift group and 51.0 ± 6.1 mm in the 2-min shift group. These two parameters were significantly different between the two groups. There was no significant difference in the other values related to CPR quality. CONCLUSIONS: Our findings indicated that 1 min of chest compressions with a 1-min rest maintained a better quality of CPR while wearing a PAPR.

Chest compressions during ventilation in out-of-hospital cardiopulmonary resuscitation cause fragmentation of the airflow.

INTRODUCTION: When a patient suffers an out-of-hospital cardiac arrest, ventilation and chest compressions are often given simultaneously during cardiopulmonary resuscitation. These simultaneous chest compressions may cause a fragmentation of the airflow, which may lead to an ineffective ventilation. This study focusses on the occurrence and quantification of this fragmentation and its effect on ventilation. MATERIALS AND METHODS: This study is a single-center observational study, held at Ghent University Hospital. A custom-built bidirectional flow sensor was used to quantify the volumes of ventilation. Adult cardiac arrest patients who were prehospitally intubated and resuscitated by the medical emergency team were eligible for inclusion. Data of the patients who were ventilated and received simultaneous chest compressions, was used to calculate the volumes of ventilation and the amount and volumes of fragmentation. All data in this study is reported as mean (standard deviation; range). RESULTS: Data of 10 patients (7 male) with a mean age of 71 years (14;51-87) was used in this study. The mean ventilation frequency was 12/min (2;9-16), the mean minute volume and tidal volume were respectively 6.21 L (1.51;3.79-8.15) and 514 mL (99;422-682). Fragmentation of the airflow was observed in all patients, with an average of 3 (1;2-5) fragments per inspiration and a mean volume of 214 mL (65;112-341) per fragment. DISCUSSION AND CONCLUSION: Chest compressions during ventilation caused fragmentation of the airflow in all patients. There was wide variation in the number and volume of the fragments between patients. The importance of quantification of airflow volumes and the effect fragmentation of the airflow on the efficacy of ventilation can be essential in improving cardiopulmonary resuscitation techniques and therefore needs further investigation.

Leg-heel chest compression as an alternative for medical professionals in times of COVID-19.

OBJECTIVE: To evaluate leg-heel chest compression without previous training as an alternative for medical professionals and its effects on distance to potential aerosol spread during chest compression. METHODS: 20 medical professionals performed standard manual chest compression followed by leg-heel chest compression after a brief instruction on a manikin. We compared percentage of correct chest compression position, percentage of full chest recoil, percentage of correct compression depth, average compression depth, percentage of correct compression rate and average compression rate between both methods. In a second approach, potential aerosol spread during chest compression was visualized. RESULTS: Our data indicate no credible difference between manual and leg-heel compression. The distance to potential aerosol spread could have been increased by leg-heel method. CONCLUSION: Under special circumstances like COVID-19-pandemic, leg-heel chest compression may be an effective alternative without previous training compared to manual chest compression while markedly increasing the distance to the patient.

How does the side of approach impact the force delivered during external chest compression?

BACKGROUND: We investigated the biomechanics of four external chest compression (ECC) approaches involving different sides of approach and hand placement during cardiopulmonary resuscitation (CPR). METHODS: A total of 60 participants (30 women and 30 men) with CPR certification performed standard continuous 2-min ECC on a Resusci Anne manikin with real-time feedback in four scenarios: rescuer at the manikin's right side with right hand chest contact (RsRc), rescuer at the manikin's right side with left hand chest contact (RsLc), rescuer at the manikin's left side with left hand chest contact (LsLc), and rescuer at the manikin's left side with right hand chest contact (LsRc). Pressure distribution maps of the palm, peak compression pressure, and compression forces were analysed. RESULTS: The participants' mean age, height, and weight was 24.8 ± 4.8 years, 165.8 ± 8.7 cm, and 62.7 ± 13.5 kg, respectively. Of the participants, 58 and 2 were right- and left-handed, respectively. Significant between-scenario differences were observed in ulnar-side palm pressure. Ulnar-radial pressure differences were higher in the LsLc and RsRc groups than in the LsRc and RsLc groups (0.69 ± 0.62 and 0.73 ± 050 kg/cm2 vs. 0.49 ± 0.49 and 0.50 ± 0.59 kg/cm2; respectively; p < 0.05). Ulnar-radial force differences were higher in the LsLc and RsRs groups than in the sLsLc and RsRs groups. CONCLUSIONS: The higher differences in pressure and force under the LsLc and RsRc approaches may lead to higher risks of potential injury. When performing standard-quality ECC, the LsRc and RsLc approaches, in which compression pressure and force are better distributed, may be more suitable than RsRc or LsLc.

Randomised trial of epinephrine dose and flush volume in term newborn lambs.

OBJECTIVES: Neonatal resuscitation guidelines recommend 0.5-1 mL saline flush following 0.01-0.03 mg/kg of epinephrine via low umbilical venous catheter for persistent bradycardia despite effective positive pressure ventilation (PPV) and chest compressions (CC). We evaluated the effects of 1 mL vs 3 mL/kg flush volumes and 0.01 vs 0.03 mg/kg doses on return of spontaneous circulation (ROSC) and epinephrine pharmacokinetics in lambs with cardiac arrest. DESIGN: Forty term lambs in cardiac arrest were randomised to receive 0.01 or 0.03 mg/kg epinephrine followed by 1 mL or 3 mL/kg flush after effective PPV and CC. Epinephrine (with 1 mL flush) was repeated every 3 min until ROSC or until 20 min. Haemodynamics, blood gases and plasma epinephrine concentrations were monitored. RESULTS: Ten lambs had ROSC before epinephrine administration and 2 died during instrumentation. Among 28 lambs that received epinephrine, 2/6 in 0.01 mg/kg-1 mL flush, 3/6 in 0.01 mg/kg-3 mL/kg flush, 5/7 in 0.03 mg/kg-1 mL flush and 9/9 in 0.03 mg/kg-3 mL/kg flush achieved ROSC (p=0.02). ROSC was five times faster with 0.03 mg/kg epinephrine compared with 0.01 mg/kg (adjusted HR (95% CI) 5.08 (1.7 to 15.25)) and three times faster with 3 mL/kg flush compared with 1 mL flush (3.5 (1.27 to 9.71)). Plasma epinephrine concentrations were higher with 0.01 mg/kg-3 mL/kg flush (adjusted geometric mean ratio 6.0 (1.4 to 25.7)), 0.03 mg/kg-1 mL flush (11.3 (2.1 to 60.3)) and 0.03 mg/kg-3 mL/kg flush (11.0 (2.2 to 55.3)) compared with 0.01 mg/kg-1 mL flush. CONCLUSIONS: 0.03 mg/kg epinephrine dose with 3 mL/kg flush volume is associated with the highest ROSC rate, increases peak plasma epinephrine concentrations and hastens time to ROSC. Clinical trials evaluating optimal epinephrine dose and flush volume are warranted.

CPR by foot. An alternative in special circumstances? A randomized simulation study.

OBJECTIVE: To assess the differences in the quality and self-perception of CPR performed with foot technique compared to the standard technique with the hands in nursing students. METHODS: 65 university nursing students participated in a randomized simulation crossover design study. The participants randomly performed two CPR tests: CPR by foot and CPR by hands techniques. The compression-only protocol with a 2-min test was used with the Resusci Anne QCPR® manikin and Wireless Skill Reporter® software, both from Laerdal. RESULTS: Participants had lower quality when doing CPR by foot (72%) than when doing standard CPR (91%) (p = 0.006). 95% of the participants indicated standard CPR as the technique of choice, while 92% indicated that they would use CPR by foot if it was not possible to perform standard technique. CONCLUSIONS: CPR quality was lower when performing foot technique, although with positive results. It would be advisable for people with acquired CPR skills to know that they can do foot compressions in situations where they cannot use their hands.

Optimal Combination of Chest Compression Depth and Rate in Virtual Reality Resuscitation Training: A Post Hoc Analysis of the Randomized Lowlands Saves Lives Trial.

Background Dissemination of cardiopulmonary resuscitation (CPR) skills is essential for cardiac arrest survival. Virtual reality (VR)-training methods are low cost and easily available, but to meet depth requirements adaptations are required, as confirmed in a recent randomized study on currently prevailing CPR quality criteria. Recently, the promising clinical performance of new CPR quality criteria was demonstrated, based on the optimal combination of compression depth and rate. We now study compliance with these newly proposed CPR quality criteria. Methods and Results Post hoc analysis of a randomized trial compared standardized 20-minute face-to-face CPR training with VR training using the Lifesaver VR smartphone application. During a posttraining test, compression depth and rate were measured using CPR mannequins. We assessed compliance with the newly proposed CPR criteria, that is, compression rate within ±20% of 107/minute and depth within ±20% of 47 mm. We studied 352 participants, age 26 (22-31) years, 56% female, and 15% with CPR training ≤2 years. Among VR-trained participants, there was a statistically significant difference between the proportions complying with newly proposed versus the currently prevailing quality criteria (52% versus 23%, P<0.001). The difference in proportions complying with rate requirements was statistically significant (96% for the new versus 50% for current criteria, P<0.001), whereas there was no significant difference with regard to the depth requirements (55% versus 51%, P=0.45). Conclusions Lifesaver VR training, although previously found to be inferior to face-to-face training, may lead to CPR quality compliant with recently proposed, new quality criteria. If the prognostic importance of these new criteria is confirmed in additional studies, Lifesaver VR in its current form would be an easily available vector to disseminate CPR skills.