(Circulation. 1997;95:1635-1641.)
© 1997 American Heart Association, Inc.
Articles |
Assisted Ventilation Does Not Improve Outcome in a Porcine Model of Single-Rescuer Bystander Cardiopulmonary Resuscitation
From the Department of Pediatrics (R.A.B., M.D.B.), Steele Memorial Children's Research Center; University of Arizona Heart Center (R.A.B., K.B.K., R.W.H., A.B.S., C.W.O., G.A.E.), Departments of Medicine (K.B.K., C.W.O., G.A.E.), Anesthesiology (C.W.O.), and Surgery (Emergency Medicine) (A.B.S.), University of Arizona College of Medicine; and Department of Veterinary Medicine (R.W.H.), College of Agriculture, Tucson, Ariz.
Correspondence to Robert A. Berg, MD, Pediatrics/3302, 1501 N Campbell Ave/PO Box 245073, Tucson, AZ 85724-5073. E-mail rberg{at}aruba.ccit.arizona.edu.
 |
Abstract |
|---|
 Top Abstract IntroductionMethodsResultsDiscussionReferences |
|---|
Background Mouth-to-mouth rescue breathing is a barrier to the performance of bystander cardiopulmonary resuscitation (CPR). We evaluated the need for assisted ventilation during simulated single-rescuer bystander CPR in a swine model of prehospital cardiac arrest.
Methods and Results Five minutes after ventricular fibrillation, swine were randomly assigned to 8 minutes of hand-bag-valve ventilation with 17% oxygen and 4% carbon dioxide plus chest compressions (CC+V), chest compressions only (CC), or no CPR (control group). Standard advanced life support was then provided. Animals successfully resuscitated received 1 hour of intensive care support and were observed for 24 hours. All 10 CC animals, 9 of the 10 CC+V animals, and 4 of the 6 control animals attained return of spontaneous circulation. Five of the 10 CC animals, 6 of the 10 CC+V animals, and none of the 6 control animals survived for 24 hours (CC versus controls, P=.058; CC+V versus controls, P<.03). All 24-hour survivors were normal or nearly normal neurologically.
Conclusions In this model of prehospital single-rescuer bystander CPR, successful initial resuscitation, 24-hour survival, and neurological outcome were similar after chest compressions only or chest compressions plus assisted ventilation. Both techniques tended to improve outcome compared with no bystander CPR.
Key Words: cardiopulmonary resuscitation • fibrillation • heart arrest • ventilation • survival
|
Introduction |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Most cardiac arrests occur out of hospitals.1 2 Bystander CPR substantially improves survival from these out-of-hospital cardiac arrests.3 4 5 6 7 8 9 10 11 12 13 14 However, single-rescuer bystander CPR as recommended by the American Heart Association requires mouth-to-mouth rescue breathing and CC.1
Unfortunately, mouth-to-mouth rescue breathing creates a barrier to the performance of bystander CPR. In one survey, a majority of American Heart Association–certified BCLS instructors indicated that they would not perform or would hesitate to perform mouth-to-mouth ventilation on most adult strangers.15 In another study, 45% of physicians and 80% of nurses claimed that they would not perform mouth-to-mouth resuscitation on a stranger.16 In a third investigation, only 15% of citizens indicated that they would definitely perform CC plus mouth-to-mouth ventilation, even if no one else was available and they were trained in this skill. On the other hand, if no one else was available and CC alone was equally effective, 68% said they would definitely initiate CPR on a stranger.17 In each of these studies, respondents were primarily concerned about contracting infectious diseases, such as AIDS.
Experimental data suggest that assisted ventilation may not be necessary during CPR in some circumstances.18 19 20 21 22 23 During cardiac arrest, blood flow to the myocardium is the rate-limiting step for oxygen delivery, not ventilation. In addition, passive ventilation during CC and active gasping provide substantial ventilation for brief periods of CPR as long as the airway remains patent.18 19 20 21 22 23 24 However, studies demonstrating comparable 24-hour survival from cardiac arrest after CC with or without assisted ventilation involve relatively short cardiac arrest insults, with nearly 100% survival in both experimental groups.18 20 21 Moreover, none of these studies evaluated a realistic model of single-rescuer bystander CPR techniques.
In this investigation, we evaluated the need for assisted ventilation during simulated single-rescuer bystander CPR in a swine model of prehospital, witnessed cardiac arrest. We used a VF cardiac arrest interval of 5 minutes (longer than previous survival studies). Standard single-rescuer bystander CPR was simulated for 8 minutes by a sequence of two ventilations with a gas mixture of 17% oxygen and 4% carbon dioxide (consistent with expired air from a rescue breather), followed by 15 CC at the rate of 100 per minute. The other experimental group, which received CC and no assisted ventilation, did not have an endotracheal tube in place during the 8 minutes of simulated bystander CPR. A third group of animals, the control group, received no "bystander" CPR for 13 minutes until the simulated paramedic team arrived. Our hypothesis was that initial treatment of cardiac arrests by CC with or without rescue breathing would result in comparable rates of successful resuscitation, 24-hour survival, and 24-hour good neurological outcome. Our second hypothesis was that CC with or without rescue breathing would result in improved 24-hour survival and neurological outcome compared with a no–bystander CPR control group.
|
Methods |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
CPR Model
Swine were used in the present study because they more closely reflect human thoracic and coronary anatomy than do canine preparations.25 26 27 To simulate bystander-initiated CPR in an out-of-hospital cardiac arrest, we used a 5-minute cardiac arrest VF interval before initiation of BLS, followed by 8 minutes of bystander CPR. A 2- to 5-minute cardiac arrest downtime is common before the performance of basic CPR, during which the bystander recognizes the gravity of the situation and calls for help.4 6 The average paramedic response times for out-of-hospital cardiac arrests range from 4 to 9 minutes in 16 different programs.8 In addition, defibrillation after more than 8 to 12 minutes of cardiac arrest is less effective.8 9 10 28 Therefore, a prehospital timeline of a 5-minute cardiac arrest downtime, followed by 8 minutes of bystander CPR and then defibrillation, is realistic and potentially life saving. Standard single-rescuer BLS, as per the guidelines of the American Heart Association, included two rescue breaths followed by 15 CC at the rate of 100 per minute, sequentially, until ALS was provided. The rescue breaths were provided with 17% oxygen and 4% carbon dioxide, simulating expired air from a rescue breather.29 This model included a cardiac arrest interval and CPR period that were sufficiently short to permit excellent outcomes in some animals yet sufficiently long to preclude successful resuscitation in many others. These time intervals provided an opportunity to demonstrate that standard and experimental (CC only) CPR procedures were superior to no BLS and allowed a comparison of the two techniques.
Preparation
Experimental protocols were approved by the Institutional Animal
Care and Use Committee and followed the guidelines of the American
Physiological Society. Experiments were performed on healthy domestic
swine weighing 
20 to 30 kg. After an overnight fast, the pigs were
subjected to masked induction of anesthesia with isoflurane followed by
oral endotracheal intubation. They were mechanically ventilated with a
volume-cycled Harvard ventilator (model 661; Harvard Apparatus, Inc) on
a mixture of room air and titrated isoflurane (1%). The tidal
volume was initially set at 15 mL/kg, and the ventilator rate was set
at 16 breaths per minute; ventilator settings were adjusted to maintain
end-tidal carbon dioxide at 40±2 mm Hg.
After we obtained a surgical plane of anesthesia, introducer sheaths were placed in the right internal and external jugular veins, left external jugular vein, right carotid artery, and right femoral artery via cutdown technique. Continuous arterial pressure monitoring was performed via a 7F pigtail micromanometer-tipped, solid state catheter (Millar Instruments) placed in the descending aorta near the diaphragm from the right femoral artery. A 5F coronary sinus catheter was placed via the right internal jugular vein. A 7F balloon-tipped flotation catheter was placed in the main pulmonary artery from the left external jugular vein. A 7F pigtail catheter was placed into the left ventricle via the right carotid artery. A 4F bipolar pacing catheter was advanced through an introducer sheath into the right ventricle. After VF was induced, the pacing catheter was removed, and a 5F calibrated micromanometer-tipped catheter (Millar Instruments) was advanced through the introducer into the right atrium. All catheter placement was performed under fluoroscopic guidance.
Measurements
Right atrial and thoracic aortic pressure waveforms, ECG, and
end-tidal carbon dioxide levels were continuously monitored and
recorded on a four-channel Gould ES 1000 recorder throughout the
experiment until the 1-hour simulated ICU period ended. End-tidal
carbon dioxide was measured with an infrared capnometer (model 47210A,
Hewlett Packard) through a sensor attached to the ventilator circuit at
the proximal end of the endotracheal tube. Coronary perfusion pressure
during CPR was calculated by subtracting right atrial relaxation
(mid-diastolic) pressure from simultaneous aortic relaxation
(mid-diastolic) pressure at a single point during three consecutive
compression/relaxation cycles. Arterial blood gas specimens were
obtained from the thoracic aorta; mixed venous specimens were obtained
from the main pulmonary artery; and coronary sinus specimens were
obtained via the coronary sinus catheter at baseline (before cardiac
arrest) and during CPR (11 minutes after cardiac arrest). Oxygen
saturation, PCO2, PO2,
pH, and hemoglobin levels were measured with a blood gas analyzer
(model IL-1306 with model 482 CO-oximeter; Instrumentation
Laboratories). Cardiac output and regional blood flow to the left
ventricle were determined according to a nonradioactive,
colored-microsphere technique30 31 32 33 at baseline (before
cardiac arrest) and during CPR (in the interval of 9.5 to 12 minutes
after VF). Minute ventilation during the seventh minute of CPR was
determined in 3 CC pigs with a heated pneumotachometer (Fleisch size 0;
Instrumentation Associates) attached to a well-sealed nose cone
mask.
Experimental Protocol
After baseline data were collected, isoflurane was discontinued,
and VF was induced by the application of 60-cycle alternating current
to the endocardium through the pacing electrode (Fig 1
).
VF was confirmed by the typical ECG rhythm and precipitous decrease in
arterial pressure. Mechanical ventilation was discontinued when VF was
noted. A 5-minute VF downtime was followed by an 8-minute BLS period.
Animals were randomly assigned into one of three groups: (1) standard
CC plus assisted ventilation (CC+V), (2) CC only (CC), and (3) no CPR
during the 8-minute BLS period (control group). The CC+V group had
endotracheal tubes in place and received two bag-valve-endotracheal
tube breaths followed by 15 manual CC at the rate of 100 per minute.
This process was repeated sequentially during the 8-minute CPR period.
The rescue breaths were provided with a gas mixture of 17% oxygen and
4% carbon dioxide, simulating expired air from a rescue breather. The
CC group had the endotracheal tube removed and received 8 minutes of
manual CC at the rate of 100 per minute.
|
At the end of the BLS period (13 minutes after VF was induced), all
animals received ACLS according to the American Heart Association
algorithms for VF. Electrical shock therapy was provided as if a
paramedic group had just arrived, starting with 100 J on the first
shock and followed by 200 J on any subsequent defibrillation attempt.
CC animals were reintubated during the minute immediately preceding the
first defibrillation attempt. If the three initial attempts at
defibrillation were unsuccessful, CPR was restarted, and epinephrine (1
mg/kg) was administered intravenously. After epinephrine
administration, CPR was continued for 30 seconds to allow circulation
of the epinephrine before further attempts to defibrillate. CPR by this
simulated "paramedic team" included ventilation with 100% oxygen
on a volume-cycled ventilator at a rate of 15 breaths per minute and CC
manually at a rate of 100 compressions per minute. Restoration of
spontaneous circulation was defined as unassisted pulse with a systolic
arterial pressure of 
50 mm Hg and a pulse pressure of 20
mm Hg lasting for 1 minute.
Intensive Care
All successfully resuscitated animals were supported
aggressively for 1 hour in a simulated ICU setting. Systolic blood
pressure was sustained at >80 mm Hg with dopamine and/or volume
administration, as clinically indicated. All pigs received 10
mL/kg normal saline IV during the ICU period. Ventricular
arrhythmias were treated with lidocaine or electroshock therapy as
necessary. Mechanical ventilation was provided with 100% oxygen and
adjusted to obtain an end-tidal carbon dioxide of 40±2 mm Hg.
Recurrent cardiac arrest was treated with standard CPR and ALS
according to the American Heart Association algorithms. At the end of 1
hour, all animals were weaned from pharmacological and ventilatory
support. Throughout the ICU period, isoflurane was administered, as
necessary, to maintain adequate analgesia and anesthesia. Animals that
survived the ICU period were transferred to observation cages for the
next 24 hours.
Outcome and Neurological Evaluation
Survival and neurological status were evaluated at 24 hours
after the initial cardiac arrest. To provide objective neurological
evaluation, Swine Neurological Deficit Scores and Swine Cerebral
Performance Categories were assessed.18 20 34 35 Briefly,
the neurological deficit score assigns values for deficits in
neurological functions, so that a score of 0 is normal and a score of
400 is brain death. Swine Cerebral Performance Category is a more
global assessment of neurological function, with category 1 being
normal and category 5 being brain death. After the 24-hour evaluation,
survivors were killed by an infusion of Euthanol.
Data Analysis
Heart rates and systolic and diastolic aortic and right atrial
pressures were collected from the graphic records at prearrest baseline
and 15 minutes after resuscitation. Aortic and right atrial compression
and relaxation pressures were collected from the graphic records at 6,
8, 10, and 12 minutes after induction of VF. Average left ventricular
myocardial blood flow was determined by adding epicardial and
endocardial flow values from the anterior, inferior, and lateral walls
of the left ventricle and dividing by 6.
Continuous variables, such as blood pressures, coronary perfusion pressures, blood gas analyses, electrical shocks and epinephrine doses during resuscitation, and Swine Neurological Deficit Scores, were evaluated with ANOVA. For all significant variables, differences between group means were evaluated with Scheffé's test. During BLS, comparisons between the CC+V and CC groups of blood pressures, myocardial perfusion pressures, myocardial oxygen delivery, myocardial oxygen consumption, cardiac outputs, and regional blood flows were evaluated with the use of unpaired Student's t tests. The Student's t test was used instead of ANOVA because such data were not obtained in the control group. Continuous variables are described as mean±SEM. Comparisons of discrete variables, such as rate of return of spontaneous circulation, animals receiving dopamine and lidocaine during resuscitation or ICU management, 24-hour survival, and 24-hour neurologically intact survival, were evaluated with the use of Fisher's exact test.
|
Results |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Twenty-six animals were studied (weight, 25±1 kg). All 10 CC animals, 9 of the 10 CC+V animals, and 4 of the 6 control animals attained return of spontaneous circulation. Five of the 10 CC animals and 6 of the 10 CC+V animals survived for 24 hours, whereas none of the 6 control animals survived for 24 hours. Survival in the CC+V group was statistically superior to that in the control group (P<.03), and survival in the CC group tended to be superior (P=.058). All 24-hour survivors were neurologically normal on the basis of the Swine Cerebral Performance scale (cerebral performance category 1) and normal or nearly normal on the basis of the Swine Neurological Deficit Score (5±5 for CC and 19±12 for CC+V). These 24-hour survivors were walking, drinking, eating, and acting normally.
Baseline weights, hemoglobin concentrations, and hemodynamic data
before defibrillation did not differ significantly among the three
groups (Table 1). Blood pressures obtained during CPR in
the CC+V and CC groups were generally comparable (Table 2), although the CC group had higher coronary perfusion
pressures after 1 minute of CPR than did the CC+V group (19.2±3.4
versus 9.5±1.4 mm Hg, P<.05). On the other hand,
there were no differences in aortic systolic pressure between the two
groups after 1, 3, 5, or 7 minutes of CPR (ie, 6, 8, 10, and 12 minutes
of VF), suggesting that the force of compressions was comparable in
both groups. Hemodynamic data at 15 minutes after resuscitation did not
differ among the three groups.
|
|
Difficulty with resuscitation and ICU management was further estimated
by comparing the three groups in terms of number of electrical shocks
and epinephrine doses during resuscitation and the need for dopamine or
lidocaine during resuscitation or ICU management (Table 3). No significant differences were noted, although
there was a tendency toward more epinephrine doses in the control group
compared with the CC group (P=.06).
|
Arterial and mixed venous PO2 and
SO2 levels generally did not differ among the
three groups at baseline, although the baseline mixed venous
SO2 was greater in the CC+V group than in the
control group (Table 4). Coronary sinus
PO2 and SO2 levels of
the CC and CC+V groups also did not differ at baseline. During CPR, the
arterial PO2 was higher in the CC+V group than
in the CC group. The arterial SO2 also tended
to be higher in the CC+V group than in the CC group
(P=.052). However, the two experimental groups did not
differ with respect to mixed venous or coronary sinus
PO2 or SO2 levels
during CPR. Both experimental groups had significantly lower mixed
venous PO2 and SO2
levels than the control group during CPR.
|
Baseline arterial and mixed venous pH and PCO2
levels were very similar among the three groups (Table 5). Arterial and coronary sinus pH was statistically
lower in the CC+V group than in the CC group (7.39±0.01 versus
7.44±0.01, P<.01, and 7.32±0.04 versus 7.40±0.01,
P<.05, respectively), but the mean values for the two
groups were quite similar and within normal limits. During CPR,
arterial pH was higher and PCO2 was lower in
the CC+V group than in the CC group. The mixed venous pH of the two
experimental groups was not different, but the control group was
significantly less acidotic than either of the experimental groups. In
addition, the mixed venous PCO2 tended to be
higher in the CC group than in the CC+V group (P<.06).
Coronary sinus specimens taken during CPR were markedly acidotic and
hypercarbic in both experimental groups without demonstrable group
differences.
|
Left ventricular myocardial regional blood flows were measured for 10
pigs (5 CC+V and 5 CC), but the results from 2 CC swine could not be
evaluated due to technical problems. There were no differences in left
ventricular myocardial blood flows between the experimental groups at
baseline or during CPR (Table 6). In addition, there
were no differences in cardiac output or oxygen delivery between the
two groups at baseline or during CPR. Systemic oxygen consumption did
not differ at baseline but was higher in the CC group than in the CC+V
group during CPR. There were no differences between groups in blood
flow to either kidney at baseline or during CPR. Furthermore, left
and right kidney blood flows were quite similar at baseline and during
CPR.
|
Fifteen of the 26 animals had active gasping, or agonal respirations,
during CPR. Some had only a few agonal breaths; some had five to seven
deep gasps per minute. None of these animals gasped before CC. Fig 2 demonstrates the percentage of animals with gasping
during each 2-minute interval of CPR. Eight of the 10 CC+V animals, 7
of the 10 CC animals, and none of the control animals gasped. All 11 of
the 24-hour survivors gasped versus 4 of the other 9 animals in the two
experimental groups (P<.01). After 7 minutes of CPR, the
minute ventilation was 1.85±0.99 L/min in 3 CC animals.
|
|
Discussion |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
In this realistic model of prehospital single-rescuer CPR, CC alone was as effective as CC plus assisted ventilation in terms of the important outcome variables: 24-hour survival and neurologically intact survival. The excellent outcomes were consistent with the blood gas, blood flow, spirometric, and oxygen delivery data. Although oxygenation of the arterial blood was superior with assisted ventilation during CPR, mixed venous and coronary sinus oxygenation data and left ventricular blood flow and oxygen delivery data suggest that oxygen delivery was comparable in both experimental groups. Furthermore, either form of "bystander" CPR was superior to no bystander CPR.
In 1993, Berg and colleagues18 demonstrated that swine in fibrillatory cardiac arrest that had been provided CC only for 9.5 minutes maintained arterial pH 7.33 and an arterial PCO2 of 48 mm Hg. In 1994, Chandra and colleagues19 demonstrated maintenance of adequate gas exchange for 4 minutes of CC without assisted ventilation in a canine VF model, with arterial oxygen saturation of >90% and minute ventilation of 5.2 L/min during the fourth minute of CPR. In a paralyzed swine VF model, Idris and coworkers24 noted a minute ventilation of 4.5 L/min during the first minute of CC-only CPR, but this gradually decreased to 1.7 L/min by the 10th minute of CPR.
Evidence of effective ventilation with CC-only CPR in the present study is consistent with these previous studies. The minute ventilation was 1.8 L/min after 7 minutes of CPR. In addition, arterial, mixed venous, and coronary sinus oxygen saturations were similar in the two experimental groups after 11 minutes of cardiac arrest (6 minutes with CPR). Assisted ventilation during CPR resulted in more arterial alkalemia and hypocarbia after 11 minutes of cardiac arrest, but the mixed venous and coronary sinus acid-base status was not statistically different. In summary, gas exchange was substantial during CPR with CC only and resulted in arterial, mixed venous, and coronary sinus blood gases similar to those with assisted ventilation.
While evaluating CC with no assisted ventilation in a swine VF model, Noc and colleagues23 noted that (1) spontaneous gasping occurred during CC-only CPR, (2) the gasping contributed substantially to minute ventilation during CC-only CPR, and (3) gasping was associated with improved outcome. Clark and coworkers35 similarly observed that agonal respirations occurred in 40% of 445 out-of-hospital cardiac arrests, and these gasping breaths were associated with increased survival. Our data also demonstrated that active gasping commonly occurred during CPR and was associated with better outcome.
Study Limitations
The present study has several limitations. By its very nature, it
could not be blinded. Nevertheless, the resuscitation and
postresuscitation protocols were standardized and strictly observed.
The power of this study was limited by the small number of animals. On
the other hand, there are three swine CPR 24-hour outcome studies in
which CC with and without assisted ventilation are
compared.18 20 21 Thirty-three of the 37 CC animals (89%)
and 30 of the 34 CC+V animals (86%) attained 24-hour neurologically
intact survival. The outcome has not differed by more than 1 animal in
any of these three previous studies or in the present study. The
consistency of these findings despite different experimental protocols
is an important counterweight to the argument of inadequate power in
each individual experiment.
Another limitation is that both groups received excellent CPR. It is unlikely that excellent compressions and mouth-to-mouth ventilation would be provided by a single rescuer in the field. Blood flow obviously decreases rapidly during pauses for ventilation. In this study, the CC+V animals benefited from mechanical ventilation and optimal airway management with an endotracheal tube. Mouth-to-mouth resuscitation is not as controlled, effective, or safe. Most of these factors would tend to bias the data in favor of the assisted ventilation group.
The most important limitation is the applicability of CPR in this animal model to CPR in humans. Most humans with fibrillatory cardiac arrests do not have normal coronary arteries. In addition, upper airway anatomy of pigs differs from that of humans.
Studies in the 1950s clearly demonstrated that mouth-to-mouth rescue breathing is superior to various chest compression and back compression techniques for ventilating paralyzed, anesthetized adults and children.36 37 38 39 40 41 42 43 In particular, upper airway obstruction precluded any ventilation in many of the subjects. These studies form the bases of the A and B of the ABCs of the American Heart Association. On the other hand, recent investigations of the active compression/decompression device (plunger) for CPR in humans have demonstrated that excellent minute ventilation can be attained without assisted ventilation or establishment of an airway.44 Although such ventilation may not be reliably attained without adequate airway tone or optimal positioning of the head, the potentially important roles of gasping and airway tone in cardiac arrest victims have not been fully delineated.
An important Belgian study strongly suggests that our findings are applicable to humans.13 14 The Belgian cerebral resuscitation group prospectively evaluated 3053 prehospital cardiac arrests. Physicians on the ambulance evaluated the quality and efficiency of bystander CPR. Long-term survival was comparable among those treated with good-quality CC alone (17 of 116, or 15%) and those treated with good-quality CC plus mouth-to-mouth ventilation (71 of 443, or 16%). The outcomes were superior with either of these techniques compared with those receiving no CPR (123 of 2055 survival, or 6%) or good-quality mouth-to-mouth ventilation (2 of 47, or 4%) (P<.001).
Bystander CPR can save lives, but it is usually not offered.2 3 8 11 12 13 14 45 46 Single-rescuer CC plus mouth-to-mouth ventilation is a complex psychomotor task that is difficult to learn, teach, remember, and perform.47 48 49 50 51 More importantly, bystanders are reluctant to perform mouth-to-mouth ventilation. If CC alone is similarly effective and more acceptable than CC plus mouth-to-mouth ventilation, this simpler technique may result in more lives being saved. The experimental data for this approach are sufficiently strong to justify a randomized, controlled clinical trial.
|
Selected Abbreviations and Acronyms |
|---|
|
|
Acknowledgments |
|---|
This study was supported by a grant from the Arizona Disease Control Research Commission.
Received August 13, 1996; revision received October 31, 1996; accepted November 6, 1996.
|
References |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
1. Emergency Cardiac Care Committee and Subcommittees, American Heart Association. Guidelines for cardiopulmonary resuscitation and emergency cardiac care. JAMA. 1992;268:2172-2198.
2.
Cummins RO, Ornato JP, Thies WH, Pepe PE.
Improving survival from sudden cardiac arrest: the `chain of
survival' concept: a statement for health professionals from the
Advanced Cardiac Life Support Subcommittee and the Emergency Cardiac
Care Committee, American Heart Association.
Circulation. 1991;83:1832-1847.
3. Lund I, Skulberg A. Cardiopulmonary resuscitation by lay people. Lancet. 1976;2:702-704.[Medline] [Order article via Infotrieve]
4. Cummins RO, Eisenberg MS, Hallstrom AP, Litwin PE. Survival of out-of-hospital cardiac arrest with early initiation of CPR. Am J Emerg Med. 1985;3:114-118. [Medline] [Order article via Infotrieve]
5.
Cummins RO, Eisenberg MS. Pre-hospital
cardiopulmonary resuscitation: is it effective?
JAMA. 1985;253:2408-2412.
6.
Eisenberg MS, Bergner L, Hallstrom AP. Cardiac
resuscitation in the community: importance of rapid provision and
implications for program planning. JAMA. 1979;241:1905-1907.
7. Weaver LB, Cobb LA, Hallstrom AP, Fahrenbruch C, Copass MK, Ray R. Factors influencing survival after out-of-hospital cardiac arrest. J Am Coll Cardiol. 1986;7:752-756. [Abstract]
8. Eisenberg MS, Horwood BT, Cummins RO, Reynolds-Haertle R, Hearne TR. Cardiac arrest and resuscitation: a tale of 29 cities. Ann Emerg Med. 1990;19:179-186. [Medline] [Order article via Infotrieve]
9. Eitel DR, Walton SL, Guerci AD, Hess DR, Sabulsky NK. Out-of-hospital cardiac arrest: a six-year experience in a suburban-rural system. Ann Emerg Med. 1988;17:808-812. [Medline] [Order article via Infotrieve]
10. Eisenberg MS, Hallstrom A, Bergner L. Long-term survival after out-of-hospital cardiac arrest. N Engl J Med. 1980;306:1340-1343. [Medline] [Order article via Infotrieve]
11. Ritter G, Wolfe RA, Goldstein S, Landis JR, Vasu CM, Acheson A, Leighton R, Medendrop SV. The effect of bystander CPR on survival of out-of-hospital cardiac arrest victims. Am Heart J. 1985;110:932-937. [Medline] [Order article via Infotrieve]
12.
Copley DP, Mantle JA, Rodgers WJ, Russell RO, Rachley
CE. Improved outcome for pre-hospital cardiopulmonary collapse
with resuscitation by bystanders. Circulation. 1977;56:901-905.
13. Bossaert L, Van Hoeyweghen R, and the Cerebral Resuscitation Study Group. Bystander cardiopulmonary resuscitation (CPR) in out-of-hospital cardiac arrest. Resuscitation. 1989;56:S55-S69.
14. Van Hoeyweghen RJ, Bossaert LL, Mullie A, Calle P, Martens P, Buylaert WA, Delooz H, Belgian Cerebral Resuscitation Study Group. Quality and efficiency of bystander CPR. Resuscitation. 1993;26:47-52. [Medline] [Order article via Infotrieve]
15. Ornato JP, Hallagan LF, McMahan SB, Peeples EH, Rostafinski AG. Attitudes of BCLS instructors about mouth-to-mouth resuscitation during the AIDS epidemic. Ann Emerg Med. 1990;19:151-156. [Medline] [Order article via Infotrieve]
16.
Brenner BE, Kauffman J. Reluctance of internists
and medical nurses to perform mouth-to-mouth resuscitation.
Arch Intern Med. 1993;153:1763-1769.
17.
Locke CJ, Berg RA, Sanders AS, Davis MF, Milander MH,
Kern KB, Ewy GA. Bystander cardiopulmonary resuscitation:
concerns about mouth-to-mouth contact. Arch Intern
Med. 1995;155:938-943.
18.
Berg RA, Kern KB, Sanders AB, Otto CW, Hilwig RW, Ewy
GA. Bystander cardiopulmonary resuscitation: is ventilation
necessary? Circulation. 1993;88:1907-1915.
19.
Chandra NC, Gruben KG, Tsitlik JE, Brower R, Guerci AD,
Halperin H, Weisfeldt MD, Permutt S. Observations of ventilation
during resuscitation in a canine model. Circulation. 1994;90:3070-3075.
20. Berg RA, Wilcoxson D, Hilwig RW, Kern KB, Sanders AB, Otto CW, Eklund DK, Ewy GA. The need for ventilatory support during bystander CPR. Ann Emerg Med. 1995;26:342-350.[Medline] [Order article via Infotrieve]
21. Noc M, Weil MH, Tang W, Turner T, Fukui M. Mechanical ventilation may not be essential for initial cardiopulmonary resuscitation. Chest. 1995;1083:821-827.
22. Tang W, Weil MH, Sun S, Kette D, Kette F, Gazmuri RJ, O'Connell F, Bisera J. Cardiopulmonary resuscitation by precordial compression but without mechanical ventilation. Am J Respir Crit Care Med. 1994;150:1709-1713. [Abstract]
23. Noc M, Weil MH, Sun S, Tang W, Bisera J. Spontaneous gasping during cardiopulmonary resuscitation without mechanical ventilation. Am J Respir Crit Care Med. 1994;150:861-864. [Abstract]
24. Idris AH, Banner MJ, Wenzel V, Fuerst RS, Becker LB, Melker RJ. Ventilation caused by external chest compression is unable to sustain effective gas exchange during CPR: a comparison with mechanical ventilation. Resuscitation. 1994;28:143-150. [Medline] [Order article via Infotrieve]
25. Howe BB, Fehn PA, Pensinger RR. Comparative anatomical studies of the coronary arteries of canine and porcine hearts. Acta Anat. 1968;72:13-21.
26. Schaper W, Jageneau A, Xhonneux R. The development of collateral circulation in the pig and dog heart. Cardiologia. 1967;51:321-335.
27. Bowman TA, Hughes HC. Swine as an in vivo model for electrophysiologic evaluation of cardiac pacing parameters. Pacing Clin Electrophysiol. 1984;7:198-194.
28.
Weaver WD, Copass MK, Bufi D, Ray H, Hallstrom AP, Cobb
LS. Improved neurologic recovery and survival after early
defibrillation. Circulation. 1984;69:943-948.
29. Wenzel V, Idris AH, Banner MJ, Fuerst RS, Tucker KJ. The composition of gas given by mouth-to-mouth ventilation during CPR. Chest. 1994;106;1806-1810.
30. Kern KB, Ewy GA. Minimal coronary stenoses and left ventricular blood flow during CPR. Ann Emerg Med. 1992;21:1066-1072. [Medline] [Order article via Infotrieve]
31. Kern KB, Lancaster L, Goldman S, Ewy GA. The effect of coronary artery lesions on the relationship between coronary perfusion pressure and myocardial blood flow during cardiopulmonary resuscitation in pigs. Am Heart J. 1990;120:324-333. [Medline] [Order article via Infotrieve]
32. Kern BK, Lancaster LD, Olajos M, Goldman S. A closed-chest porcine model of chronic left ventricular systolic and diastolic dysfunction after myocardial infarction. Coron Artery Dis. 1991;2:685-689.
33. Chase PB, Kern KB, Sanders AB, Otto CW, Ewy GA. The effects of graded doses of epinephrine on both non-invasive and invasive measures of myocardial perfusion and blood flow during cardiopulmonary resuscitation. Crit Care Med. 1993;21:413-419. [Medline] [Order article via Infotrieve]
34. Berg RA, Otto CW, Kern KB, Sanders AB, Ewy GA. High dose epinephrine results in greater early mortality after resuscitation from prolonged cardiac arrest in pigs: a prospective randomized study. Crit Care Med. 1994;22:282-290. [Medline] [Order article via Infotrieve]
35. Clark JJ, Larsen MP, Culley LL, Graves JR, Eisenberg MS. Incidence of agonal respirations in sudden cardiac arrest. Ann Emerg Med. 1992;2112:1464-1467.
36. Safar P, Escarraga LA, Elam JO. A comparison of the mouth-to-airway methods of artificial respiration with the chest-pressure arm-lift methods. N Engl J Med. 1958;258:671-677.
37. Safar P. Ventilatory efficacy of mouth-to-mouth artificial respiration: airway obstruction during manual and mouth-to-mouth artificial respiration. JAMA. 1958;167:335-341.
38.
Safar P. Failure of manual respiration.
J Appl Physiol. 1959;14:84-88.
39. Gordon AS, Frye CW, Gittelson L, Sadove MS, Beattie EJ Jr. Mouth-to-mouth versus manual artificial respiration for children and adults. JAMA. 1958;167:320-328.
40. Safar P, Brown TC, Holtey WJ, Wilder RJ. Ventilation and circulation with closed-chest cardiac massage in man. JAMA. 1961;176:574-576.
41. Elam JO, Brown ES, Elder JD. Artificial respiration by mouth-to-mask method: a study of the respiratory gas exchange of paralyzed patients ventilated by operator's expired air. N Engl J Med. 1985;250:749-754.
42.
Greene DG, Bauer RO, Janney CD, Elam JO. Expired
air resuscitation in paralyzed human subjects. J
Appl Physiol. 1957;11:313-318.
43. Elam JO, Greene DG, Brown ES, Clements JA. Oxygen and carbon dioxide exchange and energy cost of expired air resuscitation. JAMA. 1958;167:328-334.
44.
Cohen TJ, Tucker KJ, Lurie KG, Redberg RF, Dutton JP,
Dwyer KA, Schwab TM, Chin MC, Gelb AM, Scheinman MM, Schiller NB,
Callaham ML. Active compression-decompression: a new method of
cardiopulmonary resuscitation. JAMA. 1992;267:2916-2923.
45. Becker LB, Ostrander MP, Barrett J, Kondos GT. Outcome of CPR in a large metropolitan area: where are the survivors? Ann Emerg Med. 1991;20:355-361. [Medline] [Order article via Infotrieve]
46.
Lombardi G, Gallagher J, Gennis P. Outcome of
out-of-hospital cardiac arrest in New York City: the Pre-hospital
Arrest Survival Evaluation (PHASE) study. JAMA. 1994;271:678-683.
47. Flint LS Jr, Billi JE, Kelly K, Mandel L, Newell L, Stapelton ER. Education in adult basic life support training programs. Ann Emerg Med. 1993;22:468-474. [Medline] [Order article via Infotrieve]
48. Kaye L, Rallis SF, Mancini ME, Linhares KC, Angel ML, Donovan DS, Zajano NC, Finger JA. The problem of poor retention of cardiopulmonary resuscitation skills may lie with the instructor, not the learner or curriculum. Resuscitation. 1991;21:67-87. [Medline] [Order article via Infotrieve]
49.
Weaver FJ, Ramirez AG, Dorfman SB, Raizner AE.
Trainees' retention of cardiopulmonary resuscitation: how quickly they
forget. JAMA. 1979;241:901-903.
50.
Winchell SW, Safar P. Teaching and testing lay
and paramedical personnel in cardiopulmonary resuscitation.
Anesth Analg. 1966;45:441-449.
51. Kaye W, Mancini M. Retention of cardiopulmonary resuscitation skills by physicians, registered nurses and the general public. Crit Care Med. 1986;14:620-622.[Medline] [Order article via Infotrieve]
This article has been cited by other articles:
 |
|
 |
|
  R Ramaraj and G A Ewy Rationale for continuous chest compression cardiopulmonary resuscitation Heart, December 15, 2009; 95(24): 1978 - 1982. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. R. Sayre, R. A. Berg, D. M. Cave, R. L. Page, J. Potts, and R. D. White Hands-Only (Compression-Only) Cardiopulmonary Resuscitation: A Call to Action for Bystander Response to Adults Who Experience Out-of-Hospital Sudden Cardiac Arrest: A Science Advisory for the Public From the American Heart Association Emergency Cardiovascular Care Committee Circulation, April 22, 2008; 117(16): 2162 - 2167. [Full Text] [PDF]
|
|
|
|
 |
|
 B. J. Bobrow, L. L. Clark, G. A. Ewy, V. Chikani, A. B. Sanders, R. A. Berg, P. B. Richman, and K. B. Kern Minimally Interrupted Cardiac Resuscitation by Emergency Medical Services for Out-of-Hospital Cardiac Arrest JAMA, March 12, 2008; 299(10): 1158 - 1165. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Iwami, T. Kawamura, A. Hiraide, R. A. Berg, Y. Hayashi, T. Nishiuchi, K. Kajino, N. Yonemoto, H. Yukioka, H. Sugimoto, et al. Effectiveness of Bystander-Initiated Cardiac-Only Resuscitation for Patients With Out-of-Hospital Cardiac Arrest Circulation, December 18, 2007; 116(25): 2900 - 2907. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Steen Does Active Rescuer Ventilation Have a Place During Basic Cardiopulmonary Resuscitation? Circulation, November 27, 2007; 116(22): 2514 - 2516. [Full Text] [PDF]
|
|
|
|
|
|
G. A. Ewy, M. Zuercher, R. W. Hilwig, A. B. Sanders, R. A. Berg, C. W. Otto, M. M. Hayes, and K. B. Kern Improved Neurological Outcome With Continuous Chest Compressions Compared With 30:2 Compressions-to-Ventilations Cardiopulmonary Resuscitation in a Realistic Swine Model of Out-of-Hospital Cardiac Arrest Circulation, November 27, 2007; 116(22): 2525 - 2530. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. A. Samson, V. M. Nadkarni, P. A. Meaney, S. M. Carey, M. D. Berg, R. A. Berg, and the American Heart Association National Registry o Outcomes of in-hospital ventricular fibrillation in children. N. Engl. J. Med., June 1, 2006; 354(22): 2328 - 2339. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 The International Liaison Committee on Resuscitati The International Liaison Committee on Resuscitation (ILCOR) Consensus on Science With Treatment Recommendations for Pediatric and Neonatal Patients: Pediatric Basic and Advanced Life Support Pediatrics, May 1, 2006; 117(5): e955 - e977. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Part 4: Adult Basic Life Support Circulation, December 13, 2005; 112(24_suppl): IV-19 - IV-34. [Full Text] [PDF]
|
|
|
|
|
|
Part 2: Adult Basic Life Support Circulation, November 29, 2005; 112(22_suppl): III-5 - III-16. [Full Text] [PDF]
|
|
|
|
|
|
Part 6: Pediatric Basic and Advanced Life Support Circulation, November 29, 2005; 112(22_suppl): III-73 - III-90. [Full Text] [PDF]
|
|
|
|
 |
|
 M. Hupfl, A. Duma, T. Uray, C. Maier, N. Fiegl, N. Bogner, and P. Nagele Over-the-Head Cardiopulmonary Resuscitation Improves Efficacy in Basic Life Support Performed by Professional Medical Personnel with a Single Rescuer: A Simulation Study Anesth. Analg., July 1, 2005; 101(1): 200 - 205. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. A. Ewy Cardiocerebral Resuscitation: The New Cardiopulmonary Resuscitation Circulation, April 26, 2005; 111(16): 2134 - 2142. [Full Text] [PDF]
|
|
|
|
|
|
K. B. Kern, R. W. Hilwig, R. A. Berg, A. B. Sanders, and G. A. Ewy Importance of Continuous Chest Compressions During Cardiopulmonary Resuscitation: Improved Outcome During a Simulated Single Lay-Rescuer Scenario Circulation, February 5, 2002; 105(5): 645 - 649. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. D. Rea, M. S. Eisenberg, L. L. Culley, and L. Becker Dispatcher-Assisted Cardiopulmonary Resuscitation and Survival in Cardiac Arrest Circulation, November 20, 2001; 104(21): 2513 - 2516. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. A. Berg, A. B. Sanders, K. B. Kern, R. W. Hilwig, J. W. Heidenreich, M. E. Porter, and G. A. Ewy Adverse Hemodynamic Effects of Interrupting Chest Compressions for Rescue Breathing During Cardiopulmonary Resuscitation for Ventricular Fibrillation Cardiac Arrest Circulation, November 13, 2001; 104(20): 2465 - 2470. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. A. Berg, R. W. Hilwig, K. B. Kern, and G. A. Ewy "Bystander" Chest Compressions and Assisted Ventilation Independently Improve Outcome From Piglet Asphyxial Pulseless "Cardiac Arrest" Circulation, April 11, 2000; 101(14): 1743 - 1748. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. A. Ewy and J. P. Ornato Emergency cardiac care: introduction J. Am. Coll. Cardiol., March 15, 2000; 35(4): 825 - 880. [Full Text] [PDF]
|
|
|
|
|
|
R. A. Berg, K. B. Kern, R. W. Hilwig, and G. A. Ewy Assisted Ventilation During `Bystander' CPR in a Swine Acute Myocardial Infarction Model Does Not Improve Outcome Circulation, December 16, 1997; 96(12): 4364 - 4371. [Abstract] [Full Text]
|
|
|
|
|
|
L. B. Becker, R. A. Berg, P. E. Pepe, A. H. Idris, T. P. Aufderheide, T. A. Barnes, T. A. EdD, S. J. Stratton, and N. C. Chandra A Reappraisal of Mouth-to-Mouth Ventilation During Bystander-Initiated Cardiopulmonary Resuscitation : A Statement for Healthcare Professionals From the Ventilation Working Group of the Basic Life Support and Pediatric Life Support Subcommittees, American Heart Association Circulation, September 16, 1997; 96(6): 2102 - 2112. [Full Text]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||