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Karl B Kern

Publications and source records attributed to Karl B Kern.

At least 37 records · Page 2Linked to original sources
PubMed2004

Single-rescuer cardiopulmonary resuscitation: 'two quick breaths'--an oxymoron.

The Guidelines 2000 for CPR and ECC recommend for single lay-rescuers performing basic life support, "two quick breaths followed by 15 chest compressions", repeated until professional help arrives. It is uncertain that this can actually be accomplished by the majority of lay rescuers. We evaluated 53 first-year medical students after completing BLS CPR training to determine if they could deliver the goal of 80 compressions per minute when following this AHA BLS recommendation. Alternatively, a simplified technique of uninterrupted chest compression (UCC) BLS CPR was also taught and compared with standard BLS CPR (STD). The mean number of chest compressions/minute delivered with AHA BLS CPR was only 43 +/- 1 immediately after initial training and 49 +/- 2 when tested 6 months later. Uninterrupted chest compression BLS resulted in 113 +/- 2 compressions/min delivered immediately after training and 91 +/- 4 six months later (STD versus UCC; P < 0.0001). The mean length of time needed to provide the two breaths during STD-CPR was 14 +/- 1 and 12 +/- 1s (immediately after first training and six months after training). For STD-CPR, the mean minute ventilation was poor immediately after initial training (3.3 +/- 0.3 l/min) and further declined (1.9 +/- 0.4 l/min) at 6 months (P = 0.003). For single rescuer basic cardiopulmonary resuscitation, motivated BLS CPR-trained medical students take nearly as long as previously reported for middle-aged lay individuals to deliver these "two quick breaths". The "Guidelines 2000" recommendation for "two quick breaths" is an oxymoron, as it averages more than 13s. New recommendations for single-rescuer CPR should be considered that emphasize uninterrupted chest compressions.

Adult↗
PubMed2004

Precountershock cardiopulmonary resuscitation improves initial response to defibrillation from prolonged ventricular fibrillation: a randomized, controlled swine study.

OBJECTIVES: To compare immediate countershocks (defibrillation 1st) with precountershock cardiopulmonary resuscitation (CPR 1st) for prolonged ventricular fibrillation (VF). DESIGN: Randomized, controlled trial. SETTING: University animal laboratory. SUBJECTS: Thirty swine (27 +/- 1 kg). INTERVENTIONS: After 8 mins of untreated ventricular fibrillation, swine were randomly assigned to receive either immediate countershocks or CPR for 90 secs followed by countershocks. MEASUREMENTS AND MAIN RESULTS: After the first set of shocks, nine of 15 CPR 1st animals attained return of spontaneous circulation vs. 0 of 15 defibrillation 1st animals (p <.001), and pulseless electrical activity occurred in only one of 15 CPR 1st animals vs. ten of 15 defibrillation 1st animals (p <.01). The ultimate outcomes in the two groups were not different: Return of spontaneous circulation and 24-hr survival occurred in 15 of 15 CPR 1st and 13 of 15 defibrillation 1st animals. Good neurologic outcome at 24 hrs occurred in 12 of 15 CPR 1st and nine of 15 defibrillation 1st animals. None of the animals was successfully resuscitated with defibrillation alone; all successfully resuscitated animals were provided with chest compressions during the resuscitation. The ventricular fibrillation median frequency by fast Fourier transformation decreased during the untreated ventricular fibrillation interval in both groups (9.7 +/- 0.3 Hz and 10.1 +/- 0.2 Hz after 1 min vs. 8.8 +/- 0.3 Hz and 8.9 +/- 0.5 Hz at 8 mins, respectively). Because the ventricular fibrillation median frequency substantially increased after CPR 1st, it was much higher in the CPR 1st group before the first shock (15.1 +/- 0.9 Hz vs. 8.9 +/- 0.5 Hz, p <.001). The ventricular fibrillation median frequency before the first countershock was much higher in the animals that attained return of spontaneous circulation after the first set of shocks vs. those that did not (16.1 +/- 1.3 Hz vs. 10.0 +/- 0.6 Hz, p <.0001) CONCLUSIONS: Precountershock CPR can result in substantial physiologic benefits and superior response to initial defibrillation attempts compared with immediate defibrillation in the setting of prolonged ventricular fibrillation.

Animals↗
PubMed2004

Effect of vasopressin on postresuscitation ventricular function: unknown consequences of the recent Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care.

OBJECTIVE: To compare the effect on postresuscitation left ventricular function of vasopressin vs. epinephrine used during cardiopulmonary resuscitation in a swine model of prolonged prehospital ventricular fibrillation. DESIGN: Prospective, randomized experimental study. SETTING: University large animal resuscitation research laboratory. SUBJECTS: Forty-eight swine (29 +/- 1 kg). INTERVENTIONS: Resuscitation after 12.5 mins of untreated ventricular fibrillation, randomizing animals during cardiopulmonary resuscitation to treatment with epinephrine, vasopressin, or vasopressin followed by a vasopressin antagonist administered in the postresuscitation period. MEASUREMENTS AND MAIN RESULTS: Serial measurements of left ventricular systolic and diastolic function (prearrest, postresuscitation at 30 mins and 6 hrs) and 24-hr survival. Animals receiving vasopressin had more postresuscitation left ventricular dysfunction than those receiving epinephrine (p < .05). The vasopressin antagonist produced vasodilation and improved early postresuscitation left ventricular systolic and diastolic function but did not have a lasting effect on such postresuscitation ventricular function and decreased 24-hr survival compared with the use of vasopressin alone (3/16 vs. 10/16 survivors; p < .05). CONCLUSIONS: Vasopressin use during cardiopulmonary resuscitation results in worse postresuscitation left ventricular function early but did not compromise 24-hr outcome. Reversal of vasopressin's effect with a specific V-1 antagonist in the postresuscitation period did not improve survival.

Animals↗
PubMed2003

Effect of amiodarone on haemodynamics during cardiopulmonary resuscitation in a canine model of resistant ventricular fibrillation.

OBJECTIVE: Amiodarone has been shown to be superior to both placebo and lidocaine in improving survival to hospital admission for victims of out-of-hospital refractory ventricular fibrillation. Concern had been expressed about the known vasodilatatory effects of amiodarone if given without precedent vasoconstrictive medications. The haemodynamic effects of intravenous amiodarone administered during ongoing CPR have not been systemically investigated. Our intention was to verify if amiodarone alone produced significantly lower resuscitation haemodynamics than did either adrenaline (epinephrine) alone or the combination of amiodarone and adrenaline. DESIGN: Prospective, randomized, comparative study. SETTING: Research laboratory of a medical school. SUBJECTS: Thirty mongrel dogs. INTERVENTIONS: After 8 min of untreated VF, defibrillation was attempted once at 3 J/kg and external chest compressions and ventilation started. Those animals resistant to the defibrillation attempt were randomized, ten to an adrenaline (0.02 mg/kg) group, ten to an amiodarone (5 mg/kg) group, and ten to a group receiving a combination of both drugs. MEASUREMENTS AND MAIN RESULTS: Aortic systolic and diastolic, and coronary perfusion pressures were all significantly lower in the group receiving amiodarone alone than in the other two groups. Amiodarone combined with adrenaline produced pressures during CPR similar to adrenaline alone. CONCLUSION: Amiodarone can be safely administered simultaneously in combination with adrenaline and such a combination results in similar haemodynamic support as adrenaline alone. Amiodarone administered alone produces significantly lower coronary perfusion pressure than when combined with adrenaline.

Amiodarone↗
PubMed2003

Comparison of standard CPR versus diffuse and stacked hand position interposed abdominal compression-CPR in a swine model.

Interposed abdominal compression cardiopulmonary resuscitation (IAC-CPR) is an innovative basic life support technique requiring no mechanical adjuncts. Optimizing its performance remains a challenge. Hand-position technique over the abdomen during interposed abdominal compression (IAC) may be important. The purpose of this study was to determine if there is a difference in efficacy depending on the type of abdominal hand-position used. Two different hand positions were studied: open hands, placed side by side, resulting in diffuse abdominal compression and stacked hands, with one on top of the other, producing a more focal compression of the abdomen. Thirty swine were cannulated with micromanometer-tipped pressure transducers in the ascending aorta (Ao) and right atrium (RA), and Millar Doppler-tipped catheters in the descending aorta and inferior vena cava (IVC) to determine flow patterns during cardiopulmonary resuscitation (CPR), During CPR there were no differences in aortic systolic or right atrial systolic pressures. Both forms of IAC-CPR produced greater aortic diastolic and right atrial diastolic pressures then standard CPR (STD-CPR) (P<0.05). Coronary perfusion pressures (CPP), however, were not different. Blood flow directions and velocity patterns showed that STD-CPR chest compressions produce caudally directed blood flow in both the descending aorta and the IVC, and that such flows reverse (becoming cranially directed) during the relaxation phase of chest compression. IAC-CPR produced similar blood flow patterns in the aorta and IVC, as seen with STD-CPR. There were no differences in blood flow patterns between the different forms of IAC-CPR. No CPR-produced trauma difference was found. Abdominal hand position (diffuse or stacked) did not affect blood flow in either the aorta or IVC or resuscitation success in this experimental model. There was a trend towards better outcomes with stacked hands IAC-CPR with 90 versus 70% survival with STD-CPR.

Abdomen↗
PubMed2003

Automated external defibrillation versus manual defibrillation for prolonged ventricular fibrillation: lethal delays of chest compressions before and after countershocks.

STUDY OBJECTIVE: We sought to determine whether the delays in chest compressions and defibrillation associated with an automated external defibrillator would adversely affect outcome compared with manual defibrillation in a swine model of out-of-hospital prolonged ventricular fibrillation. METHODS: After 8 minutes of untreated ventricular fibrillation, 16 swine (33+/-4 kg) were randomly assigned to automated external defibrillator defibrillation or manual defibrillation with the same biphasic truncated exponential waveform 150-J shock through the same type of pads. Defibrillation with the automated external defibrillator was performed as recommended by the manufacturer, and manual defibrillation was provided per American Heart Association Guidelines. The primary outcome measure was 24-hour survival with good neurologic outcome. Data are described as means+/-SD. RESULTS: None of 8 animals in the automated external defibrillator group survived for 24 hours, whereas 5 of 8 animals in the manual defibrillation group survived 24 hours, all with good neurologic outcome (P=.027). The time interval from simulated defibrillator arrival to first compressions was 98+/-18 seconds in the automated external defibrillator group versus 68+/-15 seconds in the manual defibrillation group. In particular, the interval from first shock to first chest compressions was 46+/-18 seconds versus 22+/-16 seconds, respectively. The mean percentage of time that chest compressions were performed in the first minute after the first countershock was 15%+/-13% versus 40%+/-15%, respectively. As a result, return of spontaneous circulation within 5 minutes of simulated defibrillator arrival occurred in only 1 of 8 animals in the automated external defibrillator group versus 6 of 8 animals in the manual defibrillation group. CONCLUSION: The longer delays in chest compressions with automated external defibrillator defibrillation versus manual defibrillation can worsen the outcome from prolonged ventricular fibrillation.

Animals↗
PubMed2003

Cardiopulmonary Resuscitation Guidelines 2000 update: what's happened since?

PURPOSE OF REVIEW: To examine the literature for new resuscitation science since the publication of the Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiac Care. RECENT FINDINGS: The two and a half years since the publication of the Guidelines 2000 have seen the advent of a number of new and important resuscitation studies. Such studies highlight the importance of simplification of cardiopulmonary resuscitation techniques and guidelines, including the elimination of the layperson pulse check and the need for a simple form of basic life support cardiopulmonary resuscitation that decreases interruptions of chest compressions. Automatic external defibrillators, even in the hands of nontraditional first responders, are effective and safe. A second prospective, randomized clinical trial of amiodarone for refractory ventricular fibrillation has again shown positive results in improving survival to hospital admission. Finally, mild hypothermia appears to be the first effective therapy at decreasing central nervous system injury when administered after resuscitation. SUMMARY: In this report, we review these new studies and discuss how they corroborate or alter the published 2000 guidelines.

Amiodarone↗
PubMed2002

Importance of continuous chest compressions during cardiopulmonary resuscitation: improved outcome during a simulated single lay-rescuer scenario.

BACKGROUND: Interruptions to chest compression-generated blood flow during cardiopulmonary resuscitation (CPR) are detrimental. Data show that such interruptions for mouth-to-mouth ventilation require a period of "rebuilding" of coronary perfusion pressure to obtain the level achieved before the interruption. Whether such hemodynamic compromise from pausing to ventilate is enough to affect outcome is unknown. METHODS AND RESULTS: Thirty swine (weight 35 +/- 2 kg) underwent 3 minutes of untreated ventricular fibrillation before 12 minutes of basic life support CPR. Animals were randomized to receive either standard airway (A), breathing (B), and compression (C) CPR with expired-gas ventilation in a 15:2 compression-to-ventilation ratio or continuous chest compression CPR. Those randomized to the standard 15:2 group had no chest compressions for a period of 16 seconds each time the 2 ventilations were delivered. Defibrillation was attempted at 15 minutes of cardiac arrest. All resuscitated animals were supported in an intensive care environment for 1 hour, then in a maintenance facility for 24 hours. The primary end point of neurologically normal 24-hour survival was significantly better in the experimental group receiving continuous chest compression CPR (12 of 15 versus 2 of 15; P<0.0001). CONCLUSIONS: Mouth-to-mouth ventilation performed by single layperson rescuers produces substantial interruptions in chest compression-supported circulation. Continuous chest compression CPR produces greater neurologically normal 24-hour survival than standard ABC CPR when performed in a clinically realistic fashion. Any technique that minimizes lengthy interruptions of chest compressions during the first 10 to 15 minutes of basic life support should be given serious consideration in future efforts to improve outcome results from cardiac arrest.

Animals↗
PubMed2002

Optimizing ventilation in conjunction with phased chest and abdominal compression-decompression (Lifestick) resuscitation.

The best method for employment of phased chest and abdominal compression-decompression (Lifestick) cardiopulmonary resuscitation (CPR) has yet to be determined. Of particular concern with using this technique is the combining of ventilation with the phased compressions and decompressions. Twenty domestic swine (50+/-1 kg) were equally divided into four groups. Following 10 min of untreated VF, CPR was begun. Group 1 received Lifestick (LS) CPR with only passive ventilation ('passive'); Group 2 received LS-CPR with synchronized positive pressure ventilations (ppv) at a chest compression ratio of 15:2 (15:2 S); Group 3 had LS-CPR with synchronized ppv at 5:1 (5:1 S); and Group 4 received LS-CPR with asynchronous ppv at 5:1 (5:1 A). Endpoints included hemodynamics, blood gases, minute ventilation, and 24 h outcome. Asynchronous ventilation (5:1 A) had significantly worse hemodynamics including aortic and right atrial systolic, aortic diastolic, and coronary perfusion pressures than the other groups (P<0.05). Passive ventilation had the poorest arterial and mixed venous blood gases (P<0.05), but did not differ from 15:2 S in minute ventilation produced (8 vs 10 l/min). No differences in outcome were seen. The ventilation technique combined with LS-CPR can make a significant difference in hemodynamics as well as ventilation. Optimizing other forms of basic and advanced cardiac life support through different ventilation methods deserves new consideration, including a re-examination of the current single rescuer recommendation of a 15:2 ratio. Optimal ventilation strategy when using the LS device at 60 compressions per min appears to be 5:1 S. Such data is important for conducting clinical trials with this new CPR adjunct.

Abdomen↗
PubMed2002

Trials of teaching methods in basic life support (3): comparison of simulated CPR performance after first training and at 6 months, with a note on the value of re-training.

A randomised controlled trial comparing staged teaching of cardiopulmonary resuscitation (CPR) with conventional training provided the additional opportunity to investigate skill acquisition and retention in those attending conventional CPR classes. All subjects were tested immediately after their first instruction period and again at 6-9 months at an unheralded home visit. We were able to assess how far performance was related to poor acquisition of skills and how far it was related to skill decay. Out of 262 subjects who were randomised to receive conventional CPR instruction, 166 were available for home testing at 6-9 months. An invitation to attend for re-training had been accepted by 39 of them. The remaining 127 who attended only a single class comprise the principal study group, with additional comparative observations on the smaller re-trained cohort. Important failings were observed in the acquisition of skills in all modalities tested after the initial instruction. These were particularly marked in skills related to ventilation. Immediately after a class, 68% of trainees performed an effective check of breathing, but only 33% opened the airway as taught and no more than 18% provided an ideal ventilation volume. The technique of chest compression was also less than ideal. Although 80% of subjects placed their hands in an acceptable position, compression to an adequate depth and an adequate rate of compression were achieved by 54 and 63%, respectively. Seventy-eight percent demonstrated a careful approach, and 46% remembered to call for help. A carotid pulse check was simulated by 61% of trainees. When tested 6-9 months later, skill deterioration from this baseline was observed in all modalities tested except for the ventilation volume. The skill decay was significant (P<0.05) for the careful approach, performing an effective breathing check, the carotid pulse check, placing the hands in an acceptable position for chest compression, and compressing at an optimal rate. The minority who attended for re-training showed a trend to protection against skill decay for seven of the ten variables, compared with those who had attended only one training session. This improvement was significant for only two of them, but all were relatively small with limited practical value. Many who attend conventional CPR classes fail to acquire the necessary skills, and the skills that are acquired decline appreciably over the subsequent 6-9 months. The value of conventional re-training was modest in this study of community volunteers.

Adult↗
PubMed2002

Optimum compression to ventilation ratios in CPR under realistic, practical conditions: a physiological and mathematical analysis.

OBJECTIVE: To develop and evaluate a practical formula for the optimum ratio of compressions to ventilations in cardiopulmonary resuscitation (CPR). The optimum value of a variable is that for which a desired result is maximized. Here the desired result is assumed to be either oxygen delivery to peripheral tissues or a combination of oxygen delivery and waste product removal. METHOD: Equations describing oxygen delivery and blood flow during CPR as functions of the number of compressions and the number of ventilations delivered over time were developed from principles of classical physiology. These equations were solved explicitly in terms of the compression/ventilation ratio and evaluated for a wide range of conditions using Monte Carlo simulations. RESULTS: As the compression to ventilation ratio was increased from 0 to 50 or more, both oxygen delivery and the combination of oxygen delivery with blood flow increased to maximum values and then gradually declined. For variables typical of standard CPR as taught and specified in international guidelines, maximum values occurred at compression/ventilation ratios near 30:2. For variables typical of actual lay rescuer performance in the field, maximal values occurred at compression/ventilation ratios near 60:2. CONCLUSION: Current guidelines overestimate the need for ventilation during standard CPR by two to four-fold. Blood flow and oxygen delivery to the periphery can be improved by eliminating interruptions of chest compression for these unnecessary ventilations.

Blood Gas Analysis↗
PubMed2002

Treatment of post resuscitation myocardial dysfunction: aortic counterpulsation versus dobutamine.

BACKGROUND: Post resuscitation myocardial stunning is well described and recognized as a significant contributor to poor long-term outcome following cardiac arrest. Optimal strategies for treatment have not been determined. METHODS: Ten domestic swine (49+/-3 kg) underwent 15 min of untreated ventricular fibrillation before being successfully resuscitated. Left ventricular systolic and diastolic function was measured at pre-arrest baseline, at 30 min and at 6 h post resuscitation. Five animals were treated immediately after resuscitation with intra-aortic balloon counterpulsation (IABP) and five were given dobutamine (5 mcg/kg per min). RESULTS: No baseline differences were found. At 30 min post resuscitation pulmonary capillary wedge pressure and LVEDP were significantly higher (16+/-3 vs. 7+/-1 and 20+/-2 vs. 11+/-1 mmHg) while LV isovolumic relaxation ('Tau') was significantly longer (34+/-2 vs. 20+/-2 ms) in the IABP treated versus the dobutamine treated animals. Likewise, at 6 h post resuscitation LV ejection fraction was significantly less (21+/-6 vs. 39+/-4%), and LVEDP significantly higher (18 vs. 10 mmHg) in the IABP group. Heart rate was not different between the groups at any time post resuscitation. CONCLUSION: Dobutamine was superior to IABP for treatment of post resuscitation left ventricular systolic and diastolic dysfunction. The hypothesized advantage of IABP for treatment of post resuscitation myocardial stunning without excessively raising the heart rate like dobutamine was not realized.

Animals↗
PubMed2002

Post-resuscitation right ventricular dysfunction: delineation and treatment with dobutamine.

BACKGROUND: Left ventricular dysfunction after resuscitation from cardiac arrest has been well described. Treatment with dobutamine improves post-resuscitation left ventricular function. Right ventricular function following resuscitation has not been investigated. The purposes of this study were to examine right ventricular function following resuscitation and determine whether dobutamine would improve post-resuscitation right ventricular function. METHODS AND RESULTS: Right ventricular function was measured in 28 swine (29+/-1 kg) before and after resuscitation from 15 min of untreated ventricular fibrillation. Twelve animals received dobutamine at 10 mcg/kg/min while 16 animals served as untreated controls. Among controls, right ventricular dysfunction post-resuscitation was demonstrated by a decrease in right ventricular ejection fraction and an increase in right ventricular end-diastolic pressure. Among animals treated with dobutamine, there was a significant improvement in right ventricular function post-resuscitation compared to untreated controls. CONCLUSIONS: This study establishes that right ventricular systolic and diastolic dysfunction does occur after prolonged cardiac arrest from ventricular fibrillation. Dobutamine can ameliorate post-resuscitation right ventricular dysfunction.

Animals↗
PubMed2002

Postresuscitation myocardial dysfunction.

Postresuscitation myocardial dysfunction is common after prolonged cardiac arrest and can have life-threatening consequences. Experimental data suggest that systolic and diastolic left ventricular function can be adversely effected following successful resuscitation. Such dysfunction can resolve and represents true global myocardial stunning. Identified factors contributing to postresuscitation myocardial dysfunction include prolonged CPR, use of vasoconstricting drugs, and high-energy defibrillation. Potential treatments include dobutamine, KATP channel activators, and 21-aminosteroids. In the author's efforts to improve long-term survival from cardiac arrest, more attention is needed to the postresuscitation period.

Animals↗
PubMed2002

Acute ischemic syndromes. Adjunctive therapy.

The acute coronary syndromes (ACS) represent a heterogeneous group of patients along a continuum of risk from unstable angina to non-ST-segment elevation myocardial infarction. ACS is a term that has been used to describe the constellation of clinical symptoms that represent acute myocardial ischemia. This article reviews the adjunctive medications that are used during emergency cardiovasculare care for the early management of patients experiencing the ACS. The adjunctive therapies are divided into early immediate treatment and then subsequent management in the acute care setting.

Acute Disease↗
PubMed2002

Survival and neurologic outcome after cardiopulmonary resuscitation with four different chest compression-ventilation ratios.

STUDY OBJECTIVE: The optimal ratio of chest compressions to ventilations during cardiopulmonary resuscitation (CPR) is unknown. We determine 24-hour survival and neurologic outcome, comparing 4 different chest compression-ventilation CPR ratios in a porcine model of prolonged cardiac arrest and bystander CPR. METHODS: Forty swine were instrumented and subjected to 3 minutes of ventricular fibrillation followed by 12 minutes of CPR by using 1 of 4 models of chest compression-ventilation ratios as follows: (1) standard CPR with a ratio of 15:2; (2) CC-CPR, chest compressions only with no ventilations for 12 minutes; (3) 50:5-CPR, CPR with a ratio of 50:5 compressions to ventilations, as advocated by authorities in Great Britain; and (4) 100:2-CPR, 4 minutes of chest compressions only followed by CPR with a ratio of 100:2 compressions to ventilations. CPR was followed by standard advanced cardiac life support, 1 hour of critical care, and 24 hours of observation, followed by a neurologic evaluation. RESULTS: There were no statistically significant differences in 24-hour survival among the 4 groups (standard CPR, 7/10; CC-CPR, 7/10; 50:5-CPR, 8/10; 100:2-CPR, 9/10). There were significant differences in 24-hour neurologic function, as evaluated by using the swine cerebral performance category scale. The animals receiving 100:2-CPR had significantly better neurologic function at 24 hours than the standard CPR group with a 15:2 ratio (1.5 versus 2.5; P =.007). The 100:2-CPR group also had better neurologic function than the CC-CPR group, which received chest compressions with no ventilations (1.5 versus 2.3; P =.027). Coronary perfusion pressures, aortic pressures, and myocardial and kidney blood flows were not significantly different among the groups. Coronary perfusion pressure as an integrated area under the curve was significantly better in the CC-CPR group than in the standard CPR group (P =.04). Minute ventilation and PaO (2) were significantly lower in the CC-CPR group. CONCLUSION: In this experimental model of bystander CPR, the group receiving compressions only for 4 minutes followed by a compression-ventilation ratio of 100:2 achieved better neurologic outcome than the group receiving standard CPR and CC-CPR. Consideration of alternative chest compression-ventilation ratios might be appropriate.

Animals↗