Chest Compressions (chest + compression)

Distribution by Scientific Domains


Selected Abstracts


Two-thumb vs Two-finger Chest Compression in an Infant Model of Prolonged Cardiopulmonary Resuscitation

ACADEMIC EMERGENCY MEDICINE, Issue 10 2000
Michele L. Dorfsman MD
Abstract. Objective: Previous experiments in the authors swine lab have shown that cardiopulmonary resuscitation (CPR) using two-thumb chest compression with a thoracic squeeze (TT) produces higher blood and perfusion pressures when compared with the American Heart Association (AHA)-recommended two-finger (TF) technique. Previous studies were of short duration (1-2 minutes). The hypothesis was that TT would be superior to TF during prolonged CPR in an infant model. Methods: This was a prospective, randomized crossover experiment in a laboratory setting. Twenty-one AHA-certified rescuers performed basic CPR for two 10-minute periods, one with TT and the other with TF. Trials were separated by 2-14 days, and the order was randomly assigned. The experimental circuit consisted of a modified manikin with a fixed-volume arterial system attached to a neonatal monitor via an arterial pressure transducer. The arterial circuit was composed of a 50-mL bag of normal saline solution (air removed) attached to the manikin chest plate and connected to the transducer with a 20-gauge intravenous catheter and tubing. Rescuers were blinded to the arterial pressure tracing. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were recorded in mm Hg, and pulse pressures (PPs) were calculated. Data were analyzed with two-way repeated-measures analysis of variance. Sphericity assumed modeling, with Greenhouse-Geisser and Huynh-Feldt adjustments, was applied. Results: Marginal means for TT SBP (68.9), DBP (17.6), MAP (35.3), and PP (51.4) were higher than for TF SBP (44.8), DBP (12.5), MAP (23.3), and PP (32.2). All four pressures were significantly different between the two techniques (p , 0.001). Conclusion: In this infant CPR model, TT chest compression produced higher MAP, SBP, DBP, and PP when compared with TF chest compression during a clinically relevant duration of prolonged CPR. [source]


Use of an Automated Device for External Chest Compressions by First-aid Workers Unfamiliar With the Device: A Step Toward Public Access?

ACADEMIC EMERGENCY MEDICINE, Issue 12 2009
Frédéric Lapostolle MD
Abstract Objective:, The objective was to establish the feasibility of using an automated external chest compression (ECC) device among first-aid workers unfamiliar with the device. Methods:, Eighty first-aid workers unfamiliar with the Autopulse ECC device were randomized into three groups. Group 1 was given two explanatory illustrations on device use. Group 2 was given four explanatory illustrations. Group 3 was shown a 5-minute video on the placement and use of the device and allowed to handle the device for 5 minutes. The time taken to place and start the device on a mannequin was recorded. Results:, There was no significant difference among the three groups with regard to age, sex ratio, experience, and time elapsed since their last training session. No mistakes in device placement were made by any of the groups. All 80 participants started ECC in less than 160 seconds. There was no significant difference between Groups 1 and 2 in time taken to place or start the device (medians and 25,75 percentiles = 72 [54,112] vs. 86 [46,130] seconds and 154 [103,183] vs. 156 [120,197] seconds, respectively). However, Group 3 first-aid workers obtained significantly better results (19 [16,26] seconds to place and 48 [40,65] seconds to start; p<0.0001). Conclusions:, An automated ECC device can be rapidly placed and used by first-aid workers unfamiliar with the device. In the light of these results, use of the device by the general public can be envisaged. [source]


Chest compressions during resuscitation

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2009
D. L. ISBYE
No abstract is available for this article. [source]


Two-thumb vs Two-finger Chest Compression in an Infant Model of Prolonged Cardiopulmonary Resuscitation

ACADEMIC EMERGENCY MEDICINE, Issue 10 2000
Michele L. Dorfsman MD
Abstract. Objective: Previous experiments in the authors swine lab have shown that cardiopulmonary resuscitation (CPR) using two-thumb chest compression with a thoracic squeeze (TT) produces higher blood and perfusion pressures when compared with the American Heart Association (AHA)-recommended two-finger (TF) technique. Previous studies were of short duration (1-2 minutes). The hypothesis was that TT would be superior to TF during prolonged CPR in an infant model. Methods: This was a prospective, randomized crossover experiment in a laboratory setting. Twenty-one AHA-certified rescuers performed basic CPR for two 10-minute periods, one with TT and the other with TF. Trials were separated by 2-14 days, and the order was randomly assigned. The experimental circuit consisted of a modified manikin with a fixed-volume arterial system attached to a neonatal monitor via an arterial pressure transducer. The arterial circuit was composed of a 50-mL bag of normal saline solution (air removed) attached to the manikin chest plate and connected to the transducer with a 20-gauge intravenous catheter and tubing. Rescuers were blinded to the arterial pressure tracing. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were recorded in mm Hg, and pulse pressures (PPs) were calculated. Data were analyzed with two-way repeated-measures analysis of variance. Sphericity assumed modeling, with Greenhouse-Geisser and Huynh-Feldt adjustments, was applied. Results: Marginal means for TT SBP (68.9), DBP (17.6), MAP (35.3), and PP (51.4) were higher than for TF SBP (44.8), DBP (12.5), MAP (23.3), and PP (32.2). All four pressures were significantly different between the two techniques (p , 0.001). Conclusion: In this infant CPR model, TT chest compression produced higher MAP, SBP, DBP, and PP when compared with TF chest compression during a clinically relevant duration of prolonged CPR. [source]


Quality of cardiopulmonary resuscitation on manikins: on the floor and in the bed

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2009
H. JÄNTTI
Background: In general, in-hospital resuscitation is performed in a bed and out-of-hospital resuscitation on the floor. The surface under the patient may affect the cardiopulmonary resuscitation (CPR) quality; therefore, we evaluated CPR quality (the percentage of chest compressions of correct depth) and rescuer's fatigue (the mean compression depth minute by minute) when CPR is performed on a manikin on the floor or in the bed. Methods: Forty-four simulated cardiac arrest scenarios of 10 min were treated by intensive care unit (ICU) nurses in pairs using a 30 : 2 chest compression-to-ventilation ratio. The rescuer who performed the compressions was changed every 2 min. CPR was randomly performed either on the floor or in the bed without a backboard; in both settings, participants kneeled beside the manikin. Results: A total number of 1060 chest compressions, 44% with correct depth, were performed on the floor; 1068 chest compressions were performed in the bed, and 58% of these were the correct depth. These differences were not significant between groups. The mean compression depth during the scenario was 44.9±6.2 mm (mean±SD) on the floor and 43.0±5.9 mm in the bed (P=0.3). The mean chest compression depth decreased over time on both surfaces (P<0.001), indicating rescuer fatigue, but this change was not different between the groups (P=0.305). Conclusions: ICU nurses perform chest compression as effectively on the floor as in the bed. The mean chest compression depth decreases over time, but the surface had no significant effect. [source]


Can video mobile phones improve CPR quality when used for dispatcher assistance during simulated cardiac arrest?

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2009
S. R. BOLLE
Background: Because mobile telephones may support video calls, emergency medical dispatchers may now connect visually with bystanders during pre-hospital cardio-pulmonary resuscitation (CPR). We studied the quality of simulated dispatcher-assisted CPR when guidance was delivered to rescuers by video calls or audio calls from mobile phones. Methods: One hundred and eighty high school students were randomly assigned in groups of three to communicate via video calls or audio calls with experienced nurse dispatchers at a Hospital Emergency Medical Dispatch Center. CPR was performed on a recording resuscitation manikin during simulated cardiac arrest. Quality of CPR and time factors were compared depending on the type of communication used. Results: The median CPR time without chest compression (,hands-off time') was shorter in the video-call group vs. the audio-call group (303 vs. 331 s; P=0.048), but the median time to first compression was not shorter (104 vs. 102 s; P=0.29). The median time to first ventilation was insignificantly shorter in the video-call group (176 vs. 205 s; P=0.16). This group also had a slightly higher proportion of ventiliations without error (0.11 vs. 0.06; P=0.30). Conclusion: Video communication is unlikely to improve telephone CPR (t-CPR) significantly without proper training of dispatchers and when using dispatch protocols written for audio-only calls. Improved dispatch procedures and training for handling video calls require further investigation. [source]


High frequency chest compression and PEP

PEDIATRIC PULMONOLOGY, Issue S26 2004
Marlyn S. Woo MD
No abstract is available for this article. [source]


Use of an Automated Device for External Chest Compressions by First-aid Workers Unfamiliar With the Device: A Step Toward Public Access?

ACADEMIC EMERGENCY MEDICINE, Issue 12 2009
Frédéric Lapostolle MD
Abstract Objective:, The objective was to establish the feasibility of using an automated external chest compression (ECC) device among first-aid workers unfamiliar with the device. Methods:, Eighty first-aid workers unfamiliar with the Autopulse ECC device were randomized into three groups. Group 1 was given two explanatory illustrations on device use. Group 2 was given four explanatory illustrations. Group 3 was shown a 5-minute video on the placement and use of the device and allowed to handle the device for 5 minutes. The time taken to place and start the device on a mannequin was recorded. Results:, There was no significant difference among the three groups with regard to age, sex ratio, experience, and time elapsed since their last training session. No mistakes in device placement were made by any of the groups. All 80 participants started ECC in less than 160 seconds. There was no significant difference between Groups 1 and 2 in time taken to place or start the device (medians and 25,75 percentiles = 72 [54,112] vs. 86 [46,130] seconds and 154 [103,183] vs. 156 [120,197] seconds, respectively). However, Group 3 first-aid workers obtained significantly better results (19 [16,26] seconds to place and 48 [40,65] seconds to start; p<0.0001). Conclusions:, An automated ECC device can be rapidly placed and used by first-aid workers unfamiliar with the device. In the light of these results, use of the device by the general public can be envisaged. [source]


Prospective Clinical Trial, DEFI 2005: Does an AED Algorithm with More CPR Impact Out-of-Hospital Cardiac Arrest Prognosis?

ACADEMIC EMERGENCY MEDICINE, Issue 2008
Herve Degrange
Background:, Level 1 evidence is lacking for the Guidelines 2005 recommended changes in CPR and automated external defibrillator (AED) protocols. Objectives:, We conducted a block-randomized controlled trial to evaluate if changes to CPR during AED use could improve return of spontaneous circulation (ROSC) and hospital admission rates. Methods:, From September 2005 to March 2007, 200 biphasic LIFEPAKs, 500 AEDs, used by firefighters, were randomized every 2 months by fire station (clinicaltrials.gov NCT00139542). The 100 CONTROL AEDs conformed to Guidelines 2000. The 100 STUDY AEDs added pre-shock CPR and removed stacked shocks and post-shock pulse checks. In both groups, firefighters received weekly CPR training. ECG and impedance signals recorded by AEDs were reviewed to quantify CPR delivery. Median [interquartile range], *p < 0.05. Results:, Informed consent was obtained for 840 defibrillated patients (420 CONTROL vs. 420 STUDY). There were no differences in patient characteristics (age, sex, location, etiology, witnessed, bystander CPR, chest compression (CC) rate) and time from call to AED power on. The STUDY AEDs prompted for more CPR during AED use (81% [80, 83] vs. 62% [55, 67]*), resulting in more hands-on time (62% [54, 69] vs 49% [39, 57]*), more patients receiving only one shock (40 vs 33%*), and shorter pauses in CC before (9s [7, 13] vs 19s [16, 21]*) and after (11s [8, 14] vs 32s [26, 38]*) the shock. There was no difference in the rates of ROSC (48% [44, 53] vs 50% [45, 55], p = 0.63) and hospital admission (44% [40, 49] vs 45% [40, 49], p = 0.94) for the STUDY vs CONTROL groups. Conclusions:, Increasing CPR, shortening CC pauses and delivering fewer shocks resulted in no observed difference in ROSC or survival to hospital admission. The overall rate of hospitalization was higher than the historical expectation (34% hospital admission before study), possibly due to the increased emphasis on training and importance of CPR in both groups. [source]


Rescuer Fatigue: Standard versus Continuous Chest-Compression Cardiopulmonary Resuscitation

ACADEMIC EMERGENCY MEDICINE, Issue 10 2006
Joseph W. Heidenreich MD
Abstract Objectives Continuous chest-compression cardiopulmonary resuscitation (CCC-CPR) has been advocated as an alternative to standard CPR (STD-CPR). Studies have shown that CCC-CPR delivers substantially more chest compressions per minute and is easier to remember and perform than STD-CPR. One concern regarding CCC-CPR is that the rescuer may fatigue and be unable to maintain adequate compression rate or depth throughout an average emergency medical services response time. The specific aim of this study was to compare the effects of fatigue on the performance of CCC-CPR and STD-CPR on a manikin model. Methods This was a prospective, randomized crossover study involving 53 medical students performing CCC-CPR and STD-CPR on a manikin model. Students were randomized to their initial CPR group and then performed the other type of CPR after a period of at least two days. Students were evaluated on their performance of 9 minutes of CPR for each method. The primary endpoint was the number of adequate chest compressions (at least 38 mm of compression depth) delivered per minute during each of the 9 minutes. The secondary endpoints were total compressions, compression rate, and the number of breaks taken for rest. The students' performance was evaluated on the basis of Skillreporter Resusci Anne (Laerdal, Wappingers Falls, NY) recordings. Primary and secondary endpoints were analyzed by using the generalized linear mixed model for counting data. Results In the first 2 minutes, participants delivered significantly more adequate compressions per minute with CCC-CPR than STD-CPR, (47 vs. 32, p = 0.004 in the 1st minute and 39 vs. 29, p = 0.04 in the 2nd minute). For minutes 3 through 9, the differences in number of adequate compressions between groups were not significant. Evaluating the 9 minutes of CPR as a whole, there were significantly more adequate compressions in CCC-CPR vs. STD-CPR (p = 0.0003). Although the number of adequate compressions per minute declined over time in both groups, the rate of decline was significantly greater in CCC-CPR compared with STD-CPR (p = 0.0003). The mean number of total compressions delivered in the first minute was significantly greater with CCC-CPR than STD-CPR (105 per minute vs. 58 per minute, p < 0.001) and did not change over 9 minutes in either group. There were no differences in compression rates or number of breaks between groups. Conclusions CCC-CPR resulted in more adequate compressions per minute than STD-CPR for the first 2 minutes of CPR. However, the difference diminished after 3 minutes, presumably as a result of greater rescuer fatigue with CCC-CPR. Overall, CCC-CPR resulted in more total compressions per minute than STD-CPR during the entire 9 minutes of resuscitation. [source]


Knowledge and attitude towards paediatric cardiopulmonary resuscitation among the carers of patients attending the Emergency Department of the Children's Hospital at Westmead

EMERGENCY MEDICINE AUSTRALASIA, Issue 5 2009
Jonathan Cu
Abstract The present study aimed to describe the knowledge and attitudes of parents and carers in performing cardiopulmonary resuscitation on infants and children. A self-administered questionnaire distributed to a convenience sample of parents and carers attending the Emergency Department of The Children's Hospital at Westmead, Australia from February to March 2008. Main outcome measures were the prevalence of previous cardiopulmonary resuscitation training, willingness and confidence to perform cardiopulmonary resuscitation on infants and children compared with adults, and an objective assessment of knowledge of current resuscitation guidelines. A total of 348 parents and carers were surveyed; 53% had received previous cardiopulmonary resuscitation training, 75% prior to the previous year. There was no significant difference on their willingness to perform cardiopulmonary resuscitation on an adult versus a child (75.6% and 75.8% respectively, P= 0.870). However, 81% were willing to perform cardiopulmonary resuscitation on a relative whereas only 64% were willing to perform cardiopulmonary resuscitation on a stranger (P < 0.001). Respondents were moderately confident in delivering cardiopulmonary resuscitation to a collapsed child; mean score of 2.9 on 5-point Likert scale. Only 11% of respondents knew the correct rate for chest compressions and the ratio of compressions to ventilations; 8% had performed cardiopulmonary resuscitation in a real situation. Parents and carers are willing to perform cardiopulmonary resuscitation, especially on family members. However, their knowledge of the current guidelines was poor. More public education is required to update those with previous training and to encourage those who haven't to be trained. [source]


Quality of cardiopulmonary resuscitation on manikins: on the floor and in the bed

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2009
H. JÄNTTI
Background: In general, in-hospital resuscitation is performed in a bed and out-of-hospital resuscitation on the floor. The surface under the patient may affect the cardiopulmonary resuscitation (CPR) quality; therefore, we evaluated CPR quality (the percentage of chest compressions of correct depth) and rescuer's fatigue (the mean compression depth minute by minute) when CPR is performed on a manikin on the floor or in the bed. Methods: Forty-four simulated cardiac arrest scenarios of 10 min were treated by intensive care unit (ICU) nurses in pairs using a 30 : 2 chest compression-to-ventilation ratio. The rescuer who performed the compressions was changed every 2 min. CPR was randomly performed either on the floor or in the bed without a backboard; in both settings, participants kneeled beside the manikin. Results: A total number of 1060 chest compressions, 44% with correct depth, were performed on the floor; 1068 chest compressions were performed in the bed, and 58% of these were the correct depth. These differences were not significant between groups. The mean compression depth during the scenario was 44.9±6.2 mm (mean±SD) on the floor and 43.0±5.9 mm in the bed (P=0.3). The mean chest compression depth decreased over time on both surfaces (P<0.001), indicating rescuer fatigue, but this change was not different between the groups (P=0.305). Conclusions: ICU nurses perform chest compression as effectively on the floor as in the bed. The mean chest compression depth decreases over time, but the surface had no significant effect. [source]


Coronary Blood Flow Produced by Muscle Contractions Induced by Intracardiac Electrical CPR during Ventricular Fibrillation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2009
HAO WANG M.D.
It has been reported that transthoracic electrical cardiopulmonary resuscitation (ECPR) generates coronary perfusion pressures (CPP) similar to manual chest compressions (MCC). We hypothesized that intracardiac ECPR produces similar CPP. Methods: ECPR pulse train protocols were applied for 20 seconds in a porcine model following 10 seconds of ventricular fibrillation (VF), using a defibrillator housing electrode and a right ventricular coil (IC-ECPR). Each protocol consisted of 200-ms electrical pulse trains applied at a rate of 100 pulse trains/min. The protocols were grouped in skeletal-based versus cardiac-based stimulation measurements. CPP was recorded and compared to historical MCC values generated by a similar experimental design. CPP > 15 mm Hg at 30 seconds of VF following the application of an IC-ECPR protocol was defined as successful. Results: Mean CPP for all intracardiac ECPR pulse train protocols at 30 seconds of VF was 14.8 ± 3.8 mm Hg (n = 39). Mean CPP in seven successful skeletal-based IC-ECPR protocols was 19.4 ± 3.2 mm Hg, and mean CPP in 10 successful cardiac-based IC-ECPR protocols was 17.4 ± 2.1 mm Hg. Reported CPP for 15 MCC experiments at 30 seconds of VF was 22.9 ± 9.4 mm Hg (P = 0.35 compared to skeletal-based IC-ECPR, P = 0.08 compared to cardiac-based IC-ECPR). Conclusions: Intracardiac applied electrical CPR produced observable skeletal muscle contractions, measurable pressure pulses, and coronary perfusion pressures similar to MCC during a brief episode of untreated VF. [source]


Compression of the Left Ventricular Outflow Tract During Cardiopulmonary Resuscitation

ACADEMIC EMERGENCY MEDICINE, Issue 10 2009
Sung Oh Hwang MD
Abstract Objectives:, This prospective observational study was performed to investigate if the hand position used for external chest compressions is in an optimal position for compressing the ventricles during standard cardiopulmonary resuscitation (CPR). Methods:, Transesophageal echocardiography (TEE) was performed during standard CPR in 34 patients with nontraumatic cardiac arrest (24 males, mean ± standard deviation [SD] age = 56 ± 12 years). On the recorded image of TEE, an area of maximal compression (AMC) was identified, and the degree of compression at the AMC and the left ventricular stroke volume was calculated. Results:, A significant narrowing of the left ventricular outflow tract (LVOT) or the aorta was noted in all patients, with the degree of compression at the AMC ranging from 19% to 83% (mean ± SD = 49 ± 19%). The AMC was found at the aorta in 20 patients (59%) and at the LVOT in 14 patients (41%). A significant narrowing of more than 50% of the diameter at the end of the relaxation phase occurred in 15 patients (44%). On linear regression, the left ventricular stroke volume was correlated with the location of the AMC (R2 = 0.165, p = 0.017). Conclusions:, The outflow of the left ventricle is affected during standard CPR, resulting in varying degrees of narrowing in the LVOT and/or the aortic root. [source]


Pediatric Resuscitation Mock Code Practice Impacts Selected Skills

ACADEMIC EMERGENCY MEDICINE, Issue 2008
Jennifer Mackey
Objectives:, Determine the utility of a computer-controlled mannequin in training and assessment of resident pediatric resuscitation skills. Determine if mock code practice is beneficial in maintaining mastery of critical pediatric resuscitation skills. Methods:, A prospective randomized study of 22 interns (12 pediatric, 10 emergency medicine) randomized to: Group 1 (cases who participated in 3 mock codes over a 6 month period) and Group 2 (controls who did not receive mock code practice). Each intern was randomly paired in teams of two who participated at baseline in two code scenarios using the Laerdal Simbaby. The interns alternated airway and circulatory management responsibility. At 6 months all interns returned to the simulator in pairs to participate in another two pediatric code scenarios. All sessions were videotaped and time of computer initiation of scenario events recorded. Videos were examined by a pediatric emergency physician (blinded to Group participation) using a structured recording form. A general linear model was used to assess differences in response times and Fisher's exact tests for categorical data. Results:, Whether in charge of airway or circulatory management, at post test interns who had completed mock codes required less time to: recognize the need for bag mask ventilation (Diff 5.6 seconds, p < 0.005), initiate BVM (Diff 2.7 seconds, p < 0.006), intubate (Diff 22 seconds, p < 0.03), and recognizing the need for chest compressions (Diff 24 seconds, p < 0.03). There were no differences in times for recognizing the need for fluid resuscitation or for factors such as appropriate mask size, rate of ventilation, intubation success (including number of attempts), compression techniques, or IO placement. Conclusions:, Computer controlled mannequins provide reproducible measurable experiences. This study demonstrates that mock code practice may impact some, but not all, aspects of pediatric resuscitation skill retention. [source]


Comparison of 15:1, 15:2, and 30:2 Compression-to-Ventilation Ratios for Cardiopulmonary Resuscitation in a Canine Model of a Simulated, Witnessed Cardiac Arrest

ACADEMIC EMERGENCY MEDICINE, Issue 2 2008
Sung Oh Hwang MD
Abstract Objectives:, This experimental study compared the effect of compression-to-ventilation (CV) ratios of 15:1, 15:2, and 30:2 on hemodynamics and resuscitation outcome in a canine model of a simulated, witnessed ventricular fibrillation (VF) cardiac arrest. Methods:, Thirty healthy dogs, irrespective of species (mean ± SD, 19.2 ± 2.2 kg), were used in this study. A VF arrest was induced. The dogs received cardiopulmonary resuscitation (CPR) and were divided into three groups based on the applied CV ratios of 15:1, 15:2, and 30:2. After 1 minute of untreated VF, 4 minutes of basic life support (BLS) was performed. At the end of the 4 minutes, the dogs were defibrillated with an automatic external defibrillator (AED) and advanced cardiac life support (ACLS) efforts were continued for 10 minutes or until restoration of spontaneous circulation (ROSC) was attained, whichever came first. Results:, None of the hemodynamic parameters, and arterial oxygen profiles was significantly different between the three groups during BLS- and ACLS-CPR. Eight dogs (80%) from each group achieved ROSC during BLS and ACLS. The survival rate was not different between the three groups. In the 15:1 and 30:2 groups, the number of compressions delivered over 1 minute were significantly greater than in the 15:2 group (73.1 ± 8.1 and 69.0 ± 6.9 to 56.3 ± 6.8; p < 0.01). The time for ventilation during which compressions were stopped at each minute was significantly lower in the 15:1 and 30:2 groups than in the 15:2 group (15.4 ± 3.9 and 17.1 ± 2.7 to 25.2 ± 2.6 sec/min; p < 0.01). Conclusions:, In a canine model of witnessed VF using a simulated scenario, CPR with three CV ratios, 15:1, 15:2, and 30:2, did not result in any differences in hemodynamics, arterial oxygen profiles, and resuscitation outcome among the three groups. CPR with a CV ratio of 15:1 provided comparable chest compressions and shorter pauses for ventilation between each cycle compared to a CV ratio of 30:2. [source]