Initial treatment of ventricular fibrillation: defibrillation or drug therapy

The belief that defibrillation of unwitnessed ventricular fibrillation frequently results in asystole, combined with perceived low survival rates, led to deviation from "standard" advanced cardiac life support (ACLS) by physicians directing paramedics in the field. In nonstandard ACLS, intubation or drug therapy preceded defibrillation. This study retrospectively compared standard and nonstandard ACLS for ventricular fibrillation. The long-term survival rates were 12.3% (7/57) and 3.6% (6/168) for the two forms of ACLS, respectively (p = 0.03). The incidence of postcountershock asystole was 35% and 28% (p = 0.45). The survival rates for patients with a postcountershock rhythm and a pulse were 83% and 17% after standard and nonstandard ACLS (p less than 0.0001). Other factors reported to have a significant effect on survival were compared, and no significant differences (p greater than 0.05) were noted for mean age, sex, cardiopulmonary resuscitation (CPR) initiated by a bystander, ACLS response time, time to CPR, lay-witnessed arrest, or time to definitive care. The significant difference in the time to defibrillation (14 and 26 minutes) was expected. This is the first clinical study to clearly confirm the ACLS recommendation of early defibrillation before drug therapy in ventricular fibrillation.     

Out-of-hospital cardiac arrest in an oriental metropolitan city

To investigate the epidemiology of out-of-hospital cardiac arrest in Taipei City, Taiwan, a prospective chart review and follow-up study was conducted by collecting the prehospital cardiac arrest record from 10 designated responsible emergency departments (EDs) from August 1, 1992 through May 31, 1993. Cases with the restoration of spontaneous circulation (ROSC) were followed up until discharged from hospital. The information gathered included age, sex, bystander cardiopulmonary resuscitation, response time (time elapsed from receiving the call to arrival on the scene), advanced cardiac life support (ACLS) time (time elapsed from receiving the call to arrival at the ED), initial cardiac rhythm in the ED, ROSC, survival to discharge from the hospital, underlying disease, past history, personal history, and neurological outcome at discharge. Of 638 out-of-hospital cardiac arrests, 554 (86.7%) were nontraumatic. Response time, ACLS time, ROSC rates, and survival rates were 7.4 minutes, 21.6 minutes, 15.8%, and 1.4%, respectively. In comparing the trauma and nontrauma group, there were significant differences in age, sex, response time, and ACLS time. Between cases of patients who had ROSC and those who died, the data were statistically significant, P = .0143, showing that ACLS time was shorter in the ROSC group (19.5 v 21.9 minutes). In analysis of underlying disease, definite and probable cardiac-origin sudden deaths were found in only 120 patients, which may extend the annual sudden cardiac death rates to be 0.0053%. In conclusion, the low resuscitation and survival rates in this country were because of delayed initiation of both basic life support and ACLS. Out-of-hospital arrests of noncardiac origin had an extremely low survival rate     

Cardiopulmonary resuscitation. Historical and future perspectives

Although cardiopulmonary resuscitation (CPR) has been practiced for over a century, further study into methods for reviving victims of cardiac arrest is obviously needed. We now know that standard external CPR has numerous drawbacks, and modifications must be tested in a careful, randomized fashion. Three alternatives to standard external CPR (simultaneous compression-ventilation, interposed abdominal compression, and open-chest CPR) are currently being investigated. Of these procedures, open-chest CPR appears to show the most promise. Reproducible animal data must demonstrate the advantages of any method before widespread human studies are begun, however. If techniques seem promising in animals, well-controlled multicenter studies will be needed to verify applicability to humans. Major changes in CPR techniques should be made only after careful study, not on the basis of a limited number of reports from a single source. Resuscitation research must also extend beyond the study of techniques of cardiac massage. Although CPR is effective in some cases, clearly a person's chance of survival is directly linked to the speed of definitive care, that is, defibrillation. Research must continue into ways of providing rapid advanced cardiac care, such as home defibrillators or rapid prehospital response to the victims of cardiac arrest by those trained in advanced cardiac life support (ACLS). In addition, to counteract the problem of neurologic demise after prolonged anoxia, study of postresuscitative care must continue. Only through the combination of these measures will survival rates after cardiac arrest improve.     

Effectiveness of mechanical versus manual chest compressions in out-of-hospital cardiac arrest resuscitation: A pilot study

A prospective, randomized effectiveness trial was undertaken to compare mechanical versus manual chest compressions as measured by end-tidal CO₂ (etco₂) in out-of-hospital cardiac arrest patients receiving advanced cardiac life support (ACLS) resuscitation from a municipal third-service, emergency medical services (EMS) agency. The EMS agency responds to approximately 6,700 emergencies annually, 79 of which were cardiac arrests in 1994, the study year. Following endotracheal intubation, all cardiac arrest patients were placed on 100% oxygen via the ventilator circuit of the mechanical cardiopulmonary resuscitation (CPR) device. Patients were randomized to receive mechanical CPR (TCPR) or human/manual CPR (HCPR) based on an odd/even day basis, with TCPR being performed on odd days. etco₂ readings were obtained 5 minutes after the initiation of either TCPR or HCPR and again at the initiation of patient transport to the hospital. All patients received standard ACLS pharmacotherapy during the monitoring interval with the exception of sodium bicarbonate. CPR was continued until the patient was delivered to the hospital emergency department. Age, call response interval, initial electrocardiogram (ECG) rhythm, scene time, etco₂ measurements, and arrest outcome were identified for all patients. Twenty patients were entered into the study, with 10 in each treatment group. Three patients in the TCPR group were excluded. Measurements in the HCPR group revealed a decreasing etco₂ during the resuscitation in 8 of 10 patients (80%) and an increasing etco₂ in the remaining 2 patients. No decrease in etco₂ was noted in the TCPR group, with 4 of 7 patients (57%) actually showing an increased reading and 3 of 7 patients (43%) showing a constant etco₂ reading. The differences in the etco₂ measurements between TCPR and HCPR groups were statistically significant. Both groups were similar with regards to call response intervals, patient ages, scene times, and initial ECG rhythms. One patient in the TCPR group was admitted to the hospital but later died, leaving no survivors in the study. TCPR appears to be superior to standard HCPR as measured by etco₂ in maintaining cardiac output during ACLS resuscitation of out-of-hospital cardiac arrest patients.     

Association of Drug Therapy with Survival in Cardiac Arrest: Limited Role of Advanced Cardiac Life Support Drugs

OBJECTIVE: To generate hypotheses regarding the association of standard Advanced Cardiac Life Support (ACLS) drugs with human cardiac arrest survival. METHODS: This observational cohort study was conducted over a two-year period in the wards, intensive care units, and EDs of two tertiary care hospitals. Included werc adult patients who suffered cardiac arrest either inside or outside the hospital and who required epinephrine according to standard ACLS guidelines. Six standard ACLS drugs (given while CPR was in progress) were assessed for association with survival from resuscitation to one hour and to hospital discharge by univariate and multivariate logistic regression analyses. RESULTS: In the 529 patients studied, initial cardiac rhythm had no impact on the association between drug administration and survival. The time of drug administration (quartile of ACLS period) was associated with resuscitation for atropine (p < 0.05) and lidocaine (p < 0.01). The odds ratios (95% CIs) for successful resuscitation, after multivariate adjustment for potential confounders, were: a respiratory initiating cause, 3.7 (2.1 -6.4); each 5-minute increase in CPR-ACLS interval, 0.5 (0.4-0.7); each 5-minute duration of ACLS. 0.9 (()1.8- 1.0; atropine, 1.2 (1.0-1.3); bretylium. (0.4 (0.1-1.1); calcium 0.8 (0.2-2.4); lidocaine, 0.9 (0.7-1.1); procainamide. 21.0 (5.2-84.0) d sodium bicarbonate 1.2 (1.0-1.6). All other potential confounding variables entered into the model were not significantly associated with resuscitation. CONCLUSION: Initiating cause of arrest, time to ACLS, and duration of ACLS were important correlates of survival. Other than procainaimide, standard ACLS drugs had relatively little association with survival, but timing of administration may be an important factor. Further research using definitive large randomized controlled trials is warranted to assess the role of drug therapy in improving cardiac arrest survival.     

T ERMINATION OF R ESUSCITATION IN THE P REHOSPITAL S ETTING FOR A DULT P ATIENTS S UFFERING N ONTRAUMATIC C ARDIAC A RREST

The National Association of EMS Physicians (NAEMSP) supports out-of-hospital termination of resuscitation for adult, nontraumatic cardiac arrest patients who have not responded to full resuscitative efforts. The following factors should be considered in establishing termination of resuscitation protocols: 1) Termination of resuscitation may be considered for any adult patient who suffers sudden cardiac death that is likely to be medical. 2) Unwitnessed cardiac arrest with delayed initiation of cardiopulmonary resuscitation (CPR) beyond 6 minutes and delayed defibrillation beyond 8 minutes has a poor prognosis. 3) In the absence of “do not resuscitate” or advanced directives, a full resuscitative effort including CPR, definitive airway management, medication administration, defibrillation if necessary, and at least 20 minutes of treatment following Advanced Cardiac Life Support (ACLS) guidelines should be performed prior to declaring the patient dead. 4) A patient whose rhythm changes to, or remains in, ventricular fibrillation or ventricular tachycardia should have continued resuscitative efforts. Patients in asystole or pulseless electrical activity should be strongly considered for out-of-hospital termination of resuscitation. 5) Logistic factors should be considered, such as collapse in a public place, family wishes, and safety of the crew and public. 6) Online medical direction should be established prior to termination of resuscitation. The decision to terminate efforts should be a consensus between the on-scene paramedic and the online physician. 7) The on-scene providers and family should have access to resources, such as clergy, crisis workers, and social workers. 8) Quality review is necessary to ensure appropriate application of the termination protocol, law enforcement notification, medical examiner or coroner involvement, and family counseling.     

Is the ACLS Score a Valid Prediction Rule for Survival after Cardiac Arrest?

The ACLS (advanced cardiac life support) Score was previously developed to predict survival from out-of-hospital cardiac arrest. Whether the arrest was witnessed, initial cardiac rhythm, performance of bystander cardiopulmonary resuscitation (CPR), and the response time of the paramedic unit were determined to be predictive of survival. However, the ACLS Score has not been validated in other emergency medical services systems. OBJECTIVES: The purpose of this study was to externally validate the ACLS Score in one patient population. METHODS: This was a retrospective cohort study performed at an urban county teaching hospital. The study population consisted of consecutive adult patients treated for out-of-hospital, nontraumatic cardiac arrest, and transported to the authors' institution between November 1, 1994, and September 30, 2001. Patient records for all cardiac arrests during the study period were reviewed. Study variables included witnessed arrest, initial arrest rhythm, bystander CPR, paramedic response time, and survival to hospital discharge. Predicted probability of survival to hospital discharge was calculated for each patient using the ACLS Score. The overall predicted and observed survival rates were compared using Flora's Z score. The Hosmer-Lemeshow test was used to evaluate the model's goodness-of-fit over a range of survival probabilities. RESULTS: Of 754 cardiac arrest patients enrolled in the study period, 575 (76%) patients had documentation that allowed scoring using the ACLS Score. Twenty-five (4%) patients survived to hospital discharge. The predicted number of survivors based on the ACLS Score was 104 (18%), yielding a Flora's Z statistic of -4.46 (p < 0.0001). After categorizing predicted survival probabilities into four categories, the resulting Hosmer-Lemeshow statistic was 210 (p < 10(-6)). Both goodness-of-fit statistics demonstrated extremely poor fit of the model. A receiver operating characteristic (ROC) curve was created, yielding an area under the ROC curve of 0.33 (95% CI = 0.19 to 0.47), signifying extremely poor discrimination. CONCLUSIONS: The previously published ACLS Score was not valid when applied to an external cohort of out-of-hospital cardiac arrest patients. An externally valid model is needed to predict survival to hospital discharge following out-of-hospital cardiac arrest.     

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

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.     

Left Ventricular Compressions Improve Hemodynamics in a Swine Model of Out-of-Hospital Cardiac Arrest

Introduction: We hypothesized that chest compressions located directly over the left ventricle (LV) would improve hemodynamics, including coronary perfusion pressure (CPP), and return of spontaneous circulation (ROSC) in a swine model of cardiac arrest. Methods: Transthoracic echocardiography (echo) was used to mark the location of the aortic root and the center of the left ventricle on animals (n = 26) which were randomized to receive chest compressions in one of the two locations. After a period of ten minutes of ventricular fibrillation, basic life support (BLS) with mechanical cardiopulmonary resuscitation (CPR) was initiated and performed for ten minutes followed by advanced cardiac life support (ACLS) for an additional ten minutes. During BLS the area of maximal compression was verified using transesophageal echo. CPP and other hemodynamic variables were averaged every two minutes. Results: Mean CPP was not significantly higher in the LV group during all time intervals of resuscitation; mean CPP was significantly higher in the LV group during the 12–14 minute interval of BLS and during minutes 22–30 of ACLS (p < 0.05). Aortic systolic and diastolic pressures, right atrial systolic pressures, and end-tidal CO2 (ETCO2) were higher in the LV group during all time intervals of resuscitation (p < 0.05). Nine of the left ventricle group (69%) achieved ROSC and survived to 60 minutes compared to zero of the aortic root group (p < 0.001). Conclusions: In our swine model of cardiac arrest, chest compressions over the left ventricle improved hemodynamics and resulted in a greater proportion of animals with ROSC and survival to 60 minutes.     

Termination of resuscitation in the prehospital setting for adult patients suffering nontraumatic cardiac arrest

The National Association of EMS Physicians (NAEMSP) supports out-of-hospital termination of resuscitation for adult, nontraumatic cardiac arrest patients who have not responded to full resuscitative efforts. The following factors should be considered in establishing termination of resuscitation protocols: 1) Termination of resuscitation may be considered for any adult patient who suffers sudden cardiac death that is likely to be medical. 2) Unwitnessed cardiac arrest with delayed initiation of cardiopulmonary resuscitation (CPR) beyond 6 minutes and delayed defibrillation beyond 8 minutes has a poor prognosis. 3) In the absence of “do not resuscitate” or advanced directives, a full resuscitative effort including CPR, definitive airway management, medication administration, defibrillation if necessary, and at least 20 minutes of treatment following Advanced Cardiac Life Support (ACLS) guidelines should be performed prior to declaring the patient dead. 4) A patient whose rhythm changes to, or remains in, ventricular fibrillation or ventricular tachycardia should have continued resuscitative efforts. Patients in asystole or pulseless electrical activity should be strongly considered for out-of-hospital termination of resuscitation. 5) Logistic factors should be considered, such as collapse in a public place, family wishes, and safety of the crew and public. 6) Online medical direction should be established prior to termination of resuscitation. The decision to terminate efforts should be a consensus between the on-scene paramedic and the online physician. 7) The on-scene providers and family should have access to resources, such as clergy, crisis workers, and social workers. 8) Quality review is necessary to ensure appropriate application of the termination protocol, law enforcement notification, medical examiner or coroner involvement, and family counseling. PREHOSPITAL EMERGENCY CARE 2000;4:190-195     

Clinical use of sodium bicarbonate during cardiopulmonary resuscitation--is it used sensibly?

This study retrospectively analyzed the pattern of sodium bicarbonate (SB) use during cardiopulmonary resuscitation (CPR) in the Brain Resuscitation Clinical Trial III (BRCT III). BRCT III was a prospective clinical trial, which compared high-dose to standard-dose epinephrine during CPR. SB use was left optional in the study protocol. Records of 2915 patients were reviewed. Percentage, timing and dosage of SB administration were correlated with demographic and cardiac arrest variables and with times from collapse to Basic Life Support, to Advanced Cardiac Life Support (ACLS) and to the major interventions performed during CPR. SB was administered in 54.5% of the resuscitations. The rate of SB use decreased with increasing patient age-primarily reflecting shorter CPR attempts. Mean time intervals from arrest, from start of ACLS and from first epinephrine to administration of the first SB were 29+/-16, 19+/-13, and 10.8+/-11.1 min, respectively. No correlation was found between the rate of SB use and the pre-ACLS hypoxia times. On the other hand, a direct linear correlation was found between the rate of SB use and the duration of ACLS. We conclude that when SB was used, the time from initiation of ACLS to administration of its first dose was long and severe metabolic acidosis probably already existed at this point. Therefore, if SB is used, earlier administration may be considered. Contrary to physiological rationale, clinical decisions regarding SB use did not seem to take into consideration the duration of pre-ACLS hypoxia times. We suggest that guidelines for SB use during CPR should emphasize the importance of pre-ACLS hypoxia time in contributing to metabolic acidosis and should be more specific in defining the duration of "protracted CPR or long resuscitative efforts", the most frequent indication for SB administration.     

Survival from prehospital cardiac arrest is critically dependent upon response time

STUDY OBJECTIVE: This study correlated the delay in initiation of bystander cardiopulmonary resuscitation (ByCPR), basic (BLS) or advanced cardiac (ACLS) life support, and transport time (TT) to survival from prehospital cardiac arrest. This was a secondary endpoint in a study primarily evaluating the effect of bicarbonate on survival. DESIGN: Prospective multicenter trial. SETTING: Patients treated by urban, suburban, and rural emergency medical services (EMS) services. PATIENTS: Eight hundred and seventy-four prehospital cardiac arrest patients. INTERVENTIONS: This group underwent conventional ACLS intervention followed by empiric early administration of sodium bicarbonate noting resuscitation times. Survival was measured as the presence of vital signs on emergency department (ED) arrival. Data analysis utilized Student's t-test and logistic regression (p<0.05). RESULTS: Survival was improved with decreased time to BLS (5.52 min versus 6.81 min, p=0.047) and ACLS (7.29 min versus 9.49 min, p=0.002) intervention, as well as difference in time to return of spontaneous circulation (ROSC). The upper limit time interval after which no patient survived was 30 min for ACLS time, and 90 min for transport time. There was no overall difference in survival except at longer arrest times when considering the primary study intervention bicarbonate administration. CONCLUSION: Delay to the initiation of BLS and ACLS intervention influenced outcome from prehospital cardiac arrest negatively. There were no survivors after prolonged delay in initiation of ACLS of 30 min or greater or total resuscitation and transport time of 90 min. This result was not influenced by giving bicarbonate, the primary study intervention, except at longer arrest times.     

A 35-year-old pregnant woman presenting with sudden cardiac arrest secondary to peripartum cardiomyopathy

We present a case of successful resuscitation from cardiac arrest after 25 minutes of ventricular fibrillation (VF) secondary to peripartum cardiomyopathy. This case highlights a rare disease, but also, more importantly, the successful use of the five links of survival: early access to 9-1-1, early cardiopulmonary resuscitation (CPR), early defibrillation, early advanced life support, and postresuscitative care. We also demonstrate the importance of high-quality resuscitation practices in order to achieve a successful outcome. Manual compressions can be performed at a guidelines-compliant rate. With training, users are able to achieve high compression fractions. Pre/post shock delays can be minimized to further increase compression fraction. Nationally, CPR interruptions are often long. We recommend closer attention to uninterrupted 2-minute cycles of CPR, minimizing delays in CPR through training, and a focus on a closely choreographed approach. User review of transthoracic impedance feedback data should play a vital role in a cardiac arrest quality-improvement program.     

A 35-Year-Old Pregnant Woman Presenting with Sudden Cardiac Arrest Secondary to Peripartum Cardiomyopathy

Abstract

We present a case of successful resuscitation from cardiac arrest after 25 minutes of ventricular fibrillation (VF) secondary to peripartum cardiomyopathy. This case highlights a rare disease, but also, more importantly, the successful use of the five links of survival: early access to 9-1-1, early cardiopulmonary resuscitation (CPR), early defibrillation, early advanced life support, and postresuscitative care. We also demonstrate the importance of high-quality resuscitation practices in order to achieve a successful outcome. Manual compressions can be performed at a guidelines-compliant rate. With training, users are able to achieve high compression fractions. Pre/post shock delays can be minimized to further increase compression fraction. Nationally, CPR interruptions are often long. We recommend closer attention to uninterrupted 2-minute cycles of CPR, minimizing delays in CPR through training, and a focus on a closely choreographed approach. User review of transthoracic impedance feedback data should play a vital role in a cardiac arrest quality-improvement program.     

Advanced cardiovascular life support in AHA Guidelines 2010: Key changes from Guidelines 2005

In cardiopulmonary cerebral resuscitation (CPCR), advanced cardiovascular life support(ACLS) is a part of "chain of survival" and effects on resuscitation outcome as the interventions which increase the likehood of ROSC and as the continuing step to the post -cardiac arrest care. In order to build effective ACLS intervention, quality of basic life support is essential throughout the resuscitation effort. Based on quality CPR, ACLS providers should optimize the outcome by the integrated strategy that is consist of appropriate "drug therapy", qualified"advanced airway management", and accurate "physiologic monitoring". In this article, ACLS in American Heart Association(AHA) 2010 guidelines was reviewed and key changes from the 2005 guidelines are extracted. Not only guideline itself but training designed on the valid recommendations of guidelines are important to achieve competency of ACLS teams and better outcome of resuscitation.     

Out-of-hospital cardiopulmonary resuscitation: a population-based Norwegian study of incidence and survival.

The Trondheim region's (315 km2, population 154,000) emergency medical service (EMS) provides advanced cardiac life support (ACLS) with combined paramedic and physician response. This EMS system is commonly employed in Norway, yet no population based study of outcome in cardiac arrest has been published to date. This retrospective study reports incidence and outcome from every attempted out-of-hospital cardiopulmonary resuscitation (CPR) during 1990 through 1994 according to the Utstein template. Information on the patient's pre-morbid conditions and final outcome was obtained from hospital records. The incidence of cardiac arrest and CPR from all causes was 68 per 100,000 per year, with 83% primary cardiac aetiology. The median alarm to patient arrival interval for ambulance and emergency physician was 8 minutes and 11 minutes, respectively. The presenting rhythm was ventricular fibrillation or tachycardia in 51%, asystole in 34%, pulseless electrical activity in 8% and undetermined in 8%. Definite return of spontaneous circulation occurred in 211 patients (40%, 27 per 100,000 per year) and 57 patients (11%, 7.4 per 100,000 per year) survived to discharge. Most patients made a favourable cerebral outcome, although nine were severely disabled. This is the first population-based Norwegian study of outcome from out-of-hospital cardiac arrest in this combined paramedic/physician staffed EMS. Incidence, survival and neurological outcome are comparable with results obtained in other EMS systems.     

Partial pressure of end-tidal carbon dioxide successful predicts cardiopulmonary resuscitation in the field: a prospective observational study

Introduction

Prognosis in patients suffering out-of-hospital cardiac arrest is poor. Higher survival rates have been observed only in patients with ventricular fibrillation who were fortunate enough to have basic and advanced life support initiated soon after cardiac arrest. An ability to predict cardiac arrest outcomes would be useful for resuscitation. Changes in expired end-tidal carbon dioxide levels during cardiopulmonary resuscitation (CPR) may be a useful, noninvasive predictor of successful resuscitation and survival from cardiac arrest, and could help in determining when to cease CPR efforts.

Methods

This is a prospective, observational study of 737 cases of out-of-hospital cardiac arrest. The patients were intubated and measurements of end-tidal carbon dioxide taken. Data according to the Utstein criteria, demographic information, medical data, and partial pressure of end-tidal carbon dioxide (Pet CO ₂) values were collected for each patient in cardiac arrest by the emergency physician. We hypothesized that an end-tidal carbon dioxide level of 1.9 kPa (14.3 mmHg) or more after 20 minutes of standard advanced cardiac life support would predict restoration of spontaneous circulation (ROSC).

Results

Pet CO ₂ after 20 minutes of advanced life support averaged 0.92 ± 0.29 kPa (6.9 ± 2.2 mmHg) in patients who did not have ROSC and 4.36 ± 1.11 kPa (32.8 ± 9.1 mmHg) in those who did (P < 0.001). End-tidal carbon dioxide values of 1.9 kPa (14.3 mmHg) or less discriminated between the 402 patients with ROSC and 335 patients without. When a 20-minute end-tidal carbon dioxide value of 1.9 kPa (14.3 mmHg) or less was used as a screening test to predict ROSC, the sensitivity, specificity, positive predictive value, and negative predictive value were all 100%.

Conclusions

End-tidal carbon dioxide levels of more than 1.9 kPa (14.3 mmHg) after 20 minutes may be used to predict ROSC with accuracy. End-tidal carbon dioxide levels should be monitored during CPR and considered a useful prognostic value for determining the outcome of resuscitative efforts and when to cease CPR in the field.     

Simulated pediatric cardiopulmonary resuscitation: initial events and response times of a hospital arrest team

BACKGROUND: Cardiopulmonary resuscitation (CPR) training programs exist to enhance knowledge and skills retention. However, they do not ensure that effective CPR will be performed by trainees or resuscitation teams. One aspect of CPR effectiveness is the ability of the team to respond to an emergency call in a timely manner. METHODS: We prospectively evaluated the time required for team members to respond to an emergency call and to initiate definitive treatment in our pediatric facility. The medical staff who responded had no prior knowledge of the simulated cardiac arrest (SCA) events. All events were recorded on audio-cassette tape to determine the sequence of events and response time of arrest team members. SCA scenarios represented examples of cardiac, hematologic, renal, respiratory, and pharmacologic pathophysiology. All participants were instructed to respond as though the SCA were an actual emergency. RESULTS: From December 1991 to January 1993, 37 SCAs were evaluated. Documentation began after a concise arrest scenario had been presented to a designated nursing representative who was to be the first rescuer on the scene. The rescuer first assessed the patient's condition, activated the cardiac arrest system (median elapsed time, MET, 0.50 minutes), and then initiated single-person CPR (MET 0.58 minutes). Administration of oxygen occurred at an MET of 2.25 minutes. The first member of the arrest team to respond was the pediatric resident (MET 3.17 minutes) followed by the respiratory therapist (MET 3.20 minutes), an ICU nurse (MET 3.58 minutes), a pharmacist (MET 3.42 minutes), and anesthesiology personnel (MET 4.70 minutes). DISCUSSION: The use of SCAs (termed "Mega Code") serves as an extension of Basic Life Support and Advanced Cardiac Life Support education and provides a valuable learning experience and quality assurance tool. Limitations that might influence patient outcome during an actual in-hospital arrest have led to refinements in our cardiac arrest procedures. Of particular note was the delay in oxygen administration, which may be linked to its omission from the 1986 and 1992 American Heart Association Basic Life Support Guidelines. CONCLUSION: We believe that BLS education for hospital employees should include and emphasize oxygen delivery for resuscitation.     

Beneficial effects of vasopressin in prolonged pediatric cardiac arrest: a case series

Children who suffer cardiac arrest have a poor prognosis. Based on laboratory animal studies and clinical data in adults, vasopressin is an exciting new vasopressor treatment modality during cardiopulmonary resuscitation (CPR). In particular, vasopressin has resulted in short term resuscitation benefits as a "rescue" pressor agent in the setting of prolonged out-of-hospital CPR for ventricular fibrillation in adults. This retrospective series presents the first evidence for resuscitation benefit of bolus vasopressin therapy in the specific setting of pediatric cardiac arrest. All episodes of CPR initiated in a 120-bed tertiary care children's hospital over a three-year period (1997-2000) were reviewed. Four children in the pediatric ICU received vasopressin boluses as rescue therapy during six cardiac arrest events, following failure of conventional CPR, advanced life support, and epinephrine vasopressor therapy. Return of spontaneous circulation for greater than 60 min occurred in three of four patients (75%) and in four of six CPR events (66%) following vasopressin administration. Two of four vasopressin recipients survived >24 h; one survived to hospital discharge and one had withdrawal of supportive therapies following family discussion. Our observations are AHA level 5 (retrospective case series) evidence that vasopressin administration may be beneficial during prolonged pediatric cardiac arrest. Such reports should pave the way for prospective clinical trials comparing vasopressor medications in the setting of pediatric cardiac arrest.     

Out-of-hospital resuscitation in Tartu: effect of reorganization of Estonian EMS system

The objective of this study was to evaluate the effect of reorganization of Estonian emergency medical services (EMS) system. The outcomes of out-of-hospital resuscitation in the Tartu urban area were investigated during the 6-year study period. The main aim of reorganization was to provide rapid access to early defibrillation with simultaneous advanced cardiac life support (ACLS) procedures on the scene. The changes were implemented since summer 1994 in Tartu at first. Quick availability of a mobile intensive care unit for high-risk calls; implementation of standards for resuscitation, and routine systematic, realistic, compulsory ACLS training for all ambulance staff were established. There were 368 out-of-hospital resuscitations. Comparison of periods before and after basic reorganization of EMS system showed that the number of resuscitation attempts had evident tendency to increase. The rates of return of spontaneous circulation and survival in patients with cardiac arrest of presumed cardiac origin increased from 32.5% to 58.6% (P < .05) and from 7.5% to 25.7% (P < .05) respectively. Thus, implementation in the EMS system of mobile intensive care, ACLS units, and standard resuscitation training program diminished mortality from sudden cardiac arrest.