Assessment of Simulated Emergency Scenarios: Are Trained Observers Necessary?

OBJECTIVES: Simulation-based medical training is associated with superior educational outcomes and improved cost efficiency. Self- and peer-assessment may be a cost-effective and flexible alternative to expert-led assessment. We compared accuracy of self- and peer-assessment of untrained raters using basic evaluation tools to expert assessment using advanced validation tools including validated questionnaires and post hoc video-based analysis. METHODS: Twenty-eight simulated emergency airway management scenarios were observed and video-recorded for further assessment. Participants consisted of 28 emergency physicians who were involved in four different airway management scenarios with different roles: One scenario as a team leader, one as an assisting team member, and two as an observer. Non-technical skills (NTS) and technical skills (TS) were analyzed by three independent groups: 1) the performing team (PT) consisted of the two emergency physicians acting either in the role of team leader or team member (self-assessment); 2) the observing team (OT), consisted of two of the participating emergency physicians not involved in the current clinical scenario (peer-assessment) and assessment occurred during (OT) or directly after (PT) the simulation without prior specific interpretational training but using standardized questionnaires; and 3) the expert team (ET) consisted of two specifically trained external observers (one psychologist and one emergency physician) using video-assisted objective assessment combined with standardized questionnaires. RESULTS: Intragroup reliability demonstrated by intra-class correlation (ICC) was moderate to good for TS (ICC 0.42*) and NTS (ICC 0.55*) in PT and moderate to good for TS (ICC 0.41*) or poor for NTS (ICC 0.27) in OT. ET showed an excellent intragroup reliability for both TS (ICC 0.78*) and NTS (ICC 0.81*). Interrater reliability was significantly different between ET and PT and between ET and OT for both TS and NTS. There was no difference between OT and PT for neither TS nor NTS; *p < 0.05. CONCLUSIONS: Expert assessment of simulation-based medical training scenarios using validated checklists and performance of post hoc video-based analysis was superior to self- or peer-assessment of untrained observers for both TS and NTS.

Epinephrine improves 24-hour survival in a swine model of prolonged ventricular fibrillation demonstrating that early intraosseous is superior to delayed intravenous administration.

BACKGROUND: Vasopressors administered IV late during resuscitation efforts fail to improve survival. Intraosseous (IO) access can provide a route for earlier administration. We hypothesized that IO epinephrine after 1 minute of cardiopulmonary resuscitation (CPR) (an "optimal" IO scenario) after 10 minutes of untreated ventricular fibrillation (VF) cardiac arrest would improve outcome in comparison with either IV epinephrine after 8 minutes of CPR (a "realistic" IV scenario) or placebo controls with no epinephrine. METHODS: Thirty swine were randomized to IO epinephrine, IV epinephrine, or placebo. Important outcomes included return of spontaneous circulation (ROSC), 24-hour survival, and 24-hour survival with good neurological outcome (cerebral performance category 1). RESULTS: ROSC after 10 minutes of untreated VF was uncommon without administration of epinephrine (1 of 10), whereas ROSC was nearly universal with IO epinephrine or delayed IV epinephrine (10 of 10 and 9 of 10, respectively; P = 0.001 for either versus placebo). Twenty-four hour survival was substantially more likely after IO epinephrine than after delayed IV epinephrine (10 of 10 vs. 4 of 10, P = 0.001). None of the placebo group survived at 24 hours. Survival with good neurological outcome was more likely after IO epinephrine than after placebo (6 of 10 vs. 0 of 10, P = 0.011), and only 3 of 10 survived with good neurological outcome in the delayed IV epinephrine group (not significant versus either IO or placebo). CONCLUSION: In this swine model of prolonged VF cardiac arrest, epinephrine administration during CPR improved outcomes. In addition, early IO epinephrine improved outcomes in comparison with delayed IV epinephrine.

Predictors of resuscitation in a swine model of ischemic and nonischemic ventricular fibrillation cardiac arrest: superiority of amplitude spectral area and slope to predict a return of spontaneous circulation when resuscitation efforts are prolonged.

OBJECTIVE: We have demonstrated that a return of spontaneous circulation in the first 3 mins of resuscitation in swine is predicted by ventricular fibrillation waveform (amplitude spectral area or slope) when untreated ventricular fibrillation duration or presence of acute myocardial infarction is unknown. We hypothesized that in prolonged resuscitation efforts that return of spontaneous circulation immediately after a second or later shock with postshock chest compression is independently predicted by end-tidal CO2, coronary perfusion pressure, and ventricular fibrillation waveform measured before that shock in a swine model of ischemic and nonischemic ventricular fibrillation arrest. DESIGN: Animal intervention study with comparison to a control group. SETTING: University animal laboratory. SUBJECTS: Twenty swine. INTERVENTIONS: Myocardial infarction was induced by steel plug occlusion of the left anterior descending coronary artery. Ventricular fibrillation was untreated for 8 mins in normal swine (n=10) and acute myocardial infarction swine (n=10). MEASUREMENTS AND MAIN RESULTS: End-tidal CO2, coronary perfusion pressure, and ventricular fibrillation waveform characteristics of amplitude spectral area and slope were analyzed before second or later shocks. For an amplitude spectral area>35 mV-Hz, the odds ratio for achieving return of spontaneous circulation after that shock was 72 (95% confidence interval, 3.8-1300; p=.004) compared with an amplitude spectral area<28 mV-Hz and with an area under the receiver operator characteristic curve of 0.86. For slope>3.6 mV/s, the odds ratio for achieving return of spontaneous circulation was 36 (95% confidence interval, 2.7-480; p=.007) compared with slope<2.72 mV/s with an area under the curve of 0.86. End-tidal CO2 and coronary perfusion pressure were not predictive of return of spontaneous circulation after a shock, although coronary perfusion pressure was significantly related to both amplitude spectral area (p<.001) and slope (p<.001). CONCLUSIONS: : In prolonged untreated ventricular fibrillation arrest, the waveform characteristics of amplitude spectral area and slope predict the attainment of return of spontaneous circulation with a second or later shock. This has implications for the ideal means to customize the timing of shocks and chest compressions when return of spontaneous circulation is not promptly obtained.

Leaning during chest compressions impairs cardiac output and left ventricular myocardial blood flow in piglet cardiac arrest.

OBJECTIVE: Complete recoil of the chest wall between chest compressions during cardiopulmonary resuscitation is recommended, because incomplete chest wall recoil from leaning may decrease venous return and thereby decrease blood flow. We evaluated the hemodynamic effect of 10% or 20% lean during piglet cardiopulmonary resuscitation. DESIGN: Prospective, sequential, controlled experimental animal investigation. SETTING: University research laboratory. SUBJECTS: Domestic piglets. INTERVENTIONS: After induction of ventricular fibrillation, cardiopulmonary resuscitation was provided to ten piglets (10.7 +/- 1.2 kg) for 18 mins as six 3-min epochs with no lean, 10% lean, or 20% lean to maintain aortic systolic pressure of 80-90 mm Hg. Because the mean force to attain 80-90 mm Hg was 18 kg in preliminary studies, the equivalent of 10% and 20% lean was provided by use of 1.8- and 3.6-kg weights on the chest. MEASUREMENTS AND MAIN RESULTS: Using a linear mixed-effect regression model to control for changes in cardiopulmonary resuscitation hemodynamics over time, mean right atrial diastolic pressure was 9 +/- 0.6 mm Hg with no lean, 10 +/- 0.3 mm Hg with 10% lean (p < .01), and 13 +/- 0.3 mm Hg with 20% lean (p < .01), resulting in decreased coronary perfusion pressure with leaning. Microsphere-determined cardiac index and left ventricular myocardial blood flow were lower with 10% and 20% leaning throughout the 18 mins of cardiopulmonary resuscitation. Mean cardiac index decreased from 1.9 +/- 0.2 L . M . min with no leaning to 1.6 +/- 0.1 L . M . min with 10% leaning, and 1.4 +/- 0.2 L . M . min with 20% leaning (p < .05). The myocardial blood flow decreased from 39 +/- 7 mL . min . 100 g with no lean to 30 +/- 6 mL . min . 100 g with 10% leaning and 26 +/- 6 mL . min . 100 g with 20% leaning (p < .05). CONCLUSIONS: Leaning of 10% to 20% (i.e., 1.8-3.6 kg) during cardiopulmonary resuscitation substantially decreased coronary perfusion pressure, cardiac index, and myocardial blood flow.

Endotracheal tube intracuff pressure during helicopter transport.

STUDY OBJECTIVE: We evaluate changes in endotracheal tube intracuff pressures among intubated patients during aeromedical transport. We determine whether intracuff pressures exceed 30 cm H(2)O during aeromedical transport. METHODS: During a 12-month period, a helicopter-based rescue team prospectively recorded intracuff pressures of mechanically ventilated patients before takeoff and as soon as the maximum flight level was reached. With a commercially available pressure manometer, intracuff pressure was adjusted to < or =25 cm H(2)O before loading of the patient. The endpoint of our investigation was the increase of endotracheal tube cuff pressure during helicopter transport. RESULTS: Among 114 intubated patients, mean altitude increase was 2,260 feet (95% confidence interval [CI] 2,040 to 2,481 feet; median 2,085 feet; interquartile range [IQR] 1,477.5 to 2,900 feet). Mean flight time was 14.8 minutes (95% CI 13.1 to 16.4 minutes; median 13.5 minutes; IQR 10 to 16.1 minutes). Intracuff pressure increased from 28.7 cm H(2)O (95% CI 27.0 to 30.4 cm H(2)O [median 25 cm H(2)O; IQR 25 to 30 cm H(2)O]) to 62.6 cm H(2)O (95% CI 58.8 to 66.5 cm H(2)O; median 58; IQR 48 to 72 cm H(2)O). At cruising altitude, 98% of patients had intracuff pressures > or =30 cm H(2)O, 72% had intracuff pressures > or =50 cm H(2)O, and 20% even had intracuff pressures > or =80 cm H(2)O. CONCLUSION: Endotracheal cuff pressure during transport frequently exceeded 30 cm H(2)O during aeromedical transport. Hospital and out-of-hospital practitioners should measure and adjust endotracheal cuff pressures before and during flight.

Continued breathing followed by gasping or apnea in a swine model of ventricular fibrillation cardiac arrest.

BACKGROUND: Continued breathing following ventricular fibrillation has here-to-fore not been described. METHODS: We analyzed the spontaneous ventilatory activity during the first several minutes of ventricular fibrillation (VF) in our isoflurane anesthesized swine model of out-of-hospital cardiac arrest. The frequency and type of ventilatory activity was monitored by pneumotachometer and main stream infrared capnometer and analyzed in 61 swine during the first 3 to 6 minutes of untreated VF. RESULTS: During the first minute of VF, the air flow pattern in all 61 swine was similar to those recorded during regular spontaneous breathing during anesthesia and was clearly different from the patterns of gasping. The average rate of continued breathing during the first minute of untreated VF was 10 breaths per minute. During the second minute of untreated VF, spontaneous breathing activity either stopped or became typical of gasping. During minutes 2 to 5 of untreated VF, most animals exhibited very slow spontaneous ventilatory activity with a pattern typical of gasping; and the pattern of gasping was crescendo-decrescendo, as has been previously reported. In the absence of therapy, all ventilatory activity stopped 6 minutes after VF cardiac arrest. CONCLUSION: In our swine model of VF cardiac arrest, we documented that normal breathing continued for the first minute following cardiac arrest.

Gasping during cardiac arrest in humans is frequent and associated with improved survival.

BACKGROUND: The incidence and significance of gasping after cardiac arrest in humans are controversial. METHODS AND RESULTS: Two approaches were used. The first was a retrospective analysis of consecutive confirmed out-of-hospital cardiac arrests from the Phoenix Fire Department Regional Dispatch Center text files to determine the presence of gasping soon after collapse. The second was a retrospective analysis of 1218 patients with out-of-hospital cardiac arrests in Arizona documented by emergency medical system (EMS) first-care reports to determine the incidence of gasping after arrest in relation to the various EMS arrival times. The primary outcome measure was survival to hospital discharge. An analysis of the Phoenix Fire Department Regional Dispatch Center records of witnessed and unwitnessed out-of-hospital cardiac arrests with attempted resuscitation found that 44 of 113 (39%) of all arrested patients had gasping. An analysis of 1218 EMS-attended, witnessed, out-of-hospital cardiac arrests demonstrated that the presence or absence of gasping correlated with EMS arrival time. Gasping was present in 39 of 119 patients (33%) who arrested after EMS arrival, in 73 of 363 (20%) when EMS arrival was <7 minutes, in 50 of 360 (14%) when EMS arrival time was 7 to 9 minutes, and in 25 of 338 (7%) when EMS arrival time was >9 minutes. Survival to hospital discharge occurred in 54 of 191 patients (28%) who gasped and in 80 of 1027 (8%) who did not (adjusted odds ratio, 3.4; 95% confidence interval, 2.2 to 5.2). Among the 481 patients who received bystander cardiopulmonary resuscitation, survival to hospital discharge occurred among 30 of 77 patients who gasped (39%) versus only 38 of 404 among those who did not gasp (9%) (adjusted odds ratio, 5.1; 95% confidence interval, 2.7 to 9.4). CONCLUSIONS: Gasping or abnormal breathing is common after cardiac arrest but decreases rapidly with time. Gasping is associated with increased survival. These results suggest that the recognition and importance of gasping should be taught to bystanders and emergency medical dispatchers so as not to dissuade them from initiating prompt resuscitation efforts when appropriate.

Gasping during cardiac arrest.

PURPOSE OF REVIEW: The purpose of this study is to review the prevalence and significance of gasping in patients experiencing cardiac arrest. RECENT FINDINGS: In a recent study by Bobrow et al., gasping was identified in 33% of patients who arrested after the arrival of emergency medical services (EMS). Patients who arrested previous to EMS arrival experienced a decreasing incidence of gasping with increasing duration of cardiac arrest: 20% if EMS arrived within 7 min, 14% if EMS arrival was between 7 and 9 min, and 7% if EMS arrived after 9 min. There was a positive association between the presence of gasping and survival: 28% of those who gasped survived compared with 8% of those who did not gasp (odds ratio, 3.4, 95% confidence interval, 2.2-5.2). Among the 481 patients who received bystander cardiopulmonary resuscitation, survival to hospital discharge occurred among 39% of patients who gasped versus 9% among those who did not gasp (adjusted odds ratio, 5.1, 95% confidence interval, 2.7-9.4). SUMMARY: Gasping frequently occurs during cardiac arrest. Public and emergency medical dispatchers must be more aware of its presence and significance.

The use of Glasgow Coma Scale in injury assessment: a critical review.

PRIMARY OBJECTIVE: Patients with brain injuries are assessed using the Glasgow Coma Scale (GCS). This review evaluates the use of GCS scoring in medical literature and identifies the reasons for inaccuracy. LITERATURE SELECTION AND CRITICAL APPRAISAL: Pubmed and ISI Web of Knowledge SM were searched using specific keywords. The authors critically appraised the current state of GCS scoring, GCS definitions, the time and frequency of assessment, confounders, GCS reporting and GCS assessment schemes. MAIN OUTCOME AND RESULTS: More than 90% of the publications using GCS scoring cite the 14-item GCS rather than the 15-item GCS. The timing of the initial GCS assessment is inconstant. GCS components are seldom utilized, contributing to the loss of information. Confounders are often not reported and, if they are, not in a standardized manner. The order of the GCS components is not consistent. CONCLUSIONS: The current inconsistent and inappropriate use of GCS diminishes its reliability in both a clinical and a scientific context. A consensus statement is needed to correct this situation. Citing the correct references, early and repeated GCS assessments at defined intervals, standardized reporting of confounders and GCS component plus sum scores, and the utilization of a uniform assessment scheme are recommended.

Cardiac Arrest in the Cardiac Catheterization Laboratory: Combining Mechanical Chest Compressions and Percutaneous LV Assistance.

OBJECTIVES: The aim of this study was to evaluate the optimal treatment approach for cardiac arrest (CA) occurring in the cardiac catheterization laboratory. BACKGROUND: CA can occur in the cath lab during high-risk percutaneous coronary intervention. While attempting to correct the precipitating cause of CA, several options are available to maintain vital organ perfusion. These include manual chest compressions, mechanical chest compressions, or a percutaneous left ventricular assist device. METHODS: Eighty swine (58 ± 10 kg) were studied. The left main or proximal left anterior descending artery was occluded. Ventricular fibrillation (VFCA) was induced and circulatory support was provided with 1 of 4 techniques: either manual chest compressions (frequently interrupted), mechanical chest compressions with a piston device (LUCAS-2), an Impella 2.5 L percutaneously placed LVAD, or the combination of mechanical chest compressions and the percutaneous left ventricular assist device. The study protocol included 12 min of left main coronary occlusion, reperfusion, with defibrillation attempted after 15 min of VFCA. Primary outcome was favorable neurological function (CPC 1 or 2) at 24 h, while secondary outcomes included return of spontaneous circulation and hemodynamics. RESULTS: Manual chest compressions provided fewer neurologically intact surviving animals than the combination of a mechanical chest compressor and a percutaneous LVAD device (0% vs. 56%; p < 0.01), while no difference was found between the 2 mechanical approaches (28% vs. 35%: p = 0.75). Comparing integrated coronary perfusion pressure showed sequential improvement in hemodynamic support with mechanical devices (401 ± 230 vs. 1,337 ± 905 mm Hg/s; p = 0.06). CONCLUSIONS: Combining 2 mechanical devices provided superior 24-h survival with favorable neurological recovery compared with manual compressions during moderate duration VFCA associated with an acute coronary occlusion in the animal catheterization laboratory.

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.

BACKGROUND: The 2005 Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care changed the previous ventilations-to-chest-compression algorithm for bystander cardiopulmonary resuscitation (CPR) from 2 ventilations before each 15 chest compressions (2:15 CPR) to 30 chest compressions before 2 ventilations (30:2 CPR). It was acknowledged in the guidelines that the change was based on a consensus rather than clear evidence. This study was designed to compare 24-hour neurologically normal survival between the initial applications of continuous chest compressions without assisted ventilations with 30:2 CPR in a swine model of witnessed out-of-hospital ventricular fibrillation cardiac arrest. METHODS AND RESULTS: Sixty-four animals underwent 12 minutes of ventricular fibrillation before defibrillation attempts. They were divided into 4 groups, each with increasing durations (3, 4, 5, and 6 minutes, respectively) of untreated ventricular fibrillation before the initiation of bystander resuscitation consisting of either continuous chest compression or 30:2 CPR. After the various untreated ventricular durations plus bystander resuscitation durations, all animals were given the first defibrillation attempt 12 minutes after the induction of ventricular fibrillation, followed by the 2005 guideline-recommended advanced cardiac life support. Neurologically normal survival at 24 hours after resuscitation was observed in 23 of 33 (70%) of the animals in the continuous chest compression groups but in only 13 of 31 (42%) of the 30:2 CPR groups (P=0.025). CONCLUSIONS: In a realistic model of out-of-hospital ventricular fibrillation cardiac arrest, initial bystander administration of continuous chest compressions without assisted ventilations resulted in significantly better 24-hour postresuscitation neurologically normal survival than did the initial bystander administration of 2005 guideline-recommended 30:2 CPR.

The influence of myocardial substrate on ventricular fibrillation waveform: a swine model of acute and postmyocardial infarction.

OBJECTIVE: In cardiac arrest resulting from ventricular fibrillation, the ventricular fibrillation waveform may be a clue to its duration and predict the likelihood of shock success. However, ventricular fibrillation occurs in different myocardial substrates such as ischemia, heart failure, and structurally normal hearts. We hypothesized that ventricular fibrillation is altered by myocardial infarction and varies from the acute to postmyocardial infarction periods. DESIGN: An animal intervention study was conducted with comparison to a control group. SETTING: This study took place in a university animal laboratory. SUBJECTS: Study subjects included 37 swine. INTERVENTIONS: Myocardial infarction was induced by occlusion of the midleft anterior descending artery. Ventricular fibrillation was induced in control swine, acute myocardial infarction swine, and in postmyocardial infarction swine after a 2-wk recovery period. MEASUREMENTS AND MAIN RESULTS: Ventricular fibrillation was recorded in 11 swine with acute myocardial infarction, ten postmyocardial infarction, and 16 controls. Frequency (mean, median, dominant, and bandwidth) and amplitude-related content (slope, slope-amp [slope divided by amplitude], and amplitude-spectrum area) were analyzed. Frequencies at 5 mins of ventricular fibrillation were altered in both acute myocardial infarction (p < .001 for all frequency characteristics) and postmyocardial infarction swine (p = .015 for mean, .002 for median, .002 for dominant frequency, and <.001 for bandwidth). At 5 mins, median frequency was highest in controls, 10.9 +/- .4 Hz; lowest in acute myocardial infarction, 8.4 +/- .5 Hz; and intermediate in postmyocardial infarction, 9.7 +/- .5 Hz (p < .001 for acute myocardial infarction and p = .002 for postmyocardial infarction compared with control). Slope and amplitude-spectrum area were similar among the three groups with a shallow decline after minute 2, whereas slope-amp remained significantly altered for acute myocardial infarction swine at 5 mins (p = .003). CONCLUSIONS: Ventricular fibrillation frequencies depend on myocardial substrate and evolve from the acute through healing phases of myocardial infarction. Amplitude related measures, however, are similar among these groups. It is unknown how defibrillation may be affected by relying on the ventricular fibrillation waveform without considering myocardial substrate.

Myocardial microcirculatory dysfunction after prolonged ventricular fibrillation and resuscitation.

OBJECTIVE: The etiology of postresuscitation myocardial stunning is unknown but is thought to be related to either ischemia occurring during cardiac arrest and resuscitation efforts and/or reperfusion injury after restoration of circulation. A potential common pathway for postischemia/reperfusion end-organ dysfunction is microvascular injury. We hypothesized that myocardial microcirculatory function is markedly abnormal in the postresuscitation period. DESIGN: In vivo study of myocardial microvascular function. SETTING: University animal laboratory. SUBJECTS: Five swine (25 +/- 2 kg). INTERVENTIONS: Measurements before and after cardiac arrest and resuscitation. MEASUREMENTS AND MAIN RESULTS: Baseline data were not different among the five subjects. Left ventricular ejection fraction was significantly lower at all postresuscitation time periods (p < .05), reaching a nadir of 19% at 1 hr postresuscitation. Cardiac output declined following fibrillation and resuscitation and was significantly lower than baseline at 1 and 4 hrs postresuscitation (p < .05). Prearrest coronary flow reserve, a ratio of normal to maximal intracoronary flow velocity, was 3.4 ("normal" ratio is 2:4), but was below normal (<2) throughout the 4-hr post resuscitation period (p < .05). CONCLUSION: This in vivo study showed that normal myocardial microcirculatory function is quickly lost after prolonged ventricular fibrillation and resuscitation. As early as 30 min postresuscitation the myocardial microcirculatory function is less than 50% of its prearrest baseline level. This dysfunction persists for at least 4 hrs. During the postresuscitation period, both left ventricular ejection fraction and cardiac output decline from their prearrest levels. No cause and effect relationship was proven, but a parallel decline in left ventricular function and coronary flow reserve is evident.

Cardiac arrest during anesthesia.

PURPOSE OF REVIEW: Cardiac arrest of patients during anesthesia has been the driving force behind the development of this specialty. Safer procedures, new anesthetics, and technical improvements such as monitoring devices and ventilators have successfully reduced intraoperative mortality. Nevertheless, modern technology itself creates specific risks; and causes, diagnosis, and management of anesthesia-related cardiac arrest differ considerably from situations encountered elsewhere. RECENT FINDINGS: Cardiac arrest attributable to anesthesia occurs from 0.5 to 1 case per 10,000 interventions. Pediatric cases show a higher incidence (1.4-4.6 per 10,000). However, with the increasing age of patients, preexisting disease or trauma, and new surgical interventions cardiac arrests remain a serious concern. Environmental considerations are gradually becoming more important than mere technological improvements, and educational inputs try to create safer surroundings by recognizing human factors such as efficient communication, awareness, error culture, crew resources utilization, and preparedness for more effective crisis management. SUMMARY: The anesthetic environment has become much safer than it was 50 years ago. For a successful management of cardiac arrest during operative procedures, not only individual knowledge and skills but also institutional safety culture have to be implemented into education, training, and everyday practice of this specialty.

Cardiocerebral resuscitation improves neurologically intact survival of patients with out-of-hospital cardiac arrest.

STUDY OBJECTIVE: In an effort to improve neurologically normal survival of victims of cardiac arrest, a new out-of-hospital protocol was implemented by the emergency medical system medical directors in 2 south-central rural Wisconsin counties. The project was undertaken because the existing guidelines for care of such patients, despite their international scope and periodic updates, had not substantially improved survival rates for such patients during nearly 4 decades. METHODS: The neurologic status at or shortly after discharge was documented for adult patients with a witnessed collapse and an initially shockable rhythm. Patients during two 3-year periods were compared. During the 2001 through 2003 period, in which the 2000 American Heart Association guidelines were used, data were collected retrospectively. During the mid-2004 through mid-2007 period, patients were treated according to the principles of cardiocerebral resuscitation. Data for these patients were collected prospectively. Cerebral performance category scores were used to define the neurologic status of survivors, and a score of 1 was considered as "intact" survival. RESULTS: In the 3 years preceding the change in protocol, there were 92 witnessed arrests with an initially shockable rhythm. Eighteen patients survived (20%) and 14 (15%) were neurologically intact. During the 3 years after implementation of the new protocol, there were 89 such patients. Forty-two (47%) survived and 35 (39%) were neurologically intact. CONCLUSION: In adult patients with a witnessed cardiac arrest and an initially shockable rhythm, implementation of an out-of-hospital treatment protocol based on the principles of cardiocerebral resuscitation was associated with a dramatic improvement in neurologically intact survival.

In-hospital pediatric cardiac arrest.

The understanding of the incidence, epidemiology, etiology, and pathophysiology of pediatric cardiac arrest has evolved greatly in the past two decades. This includes recognition that cardiopulmonary resuscitation delays in cardiac arrest are especially injurious, ventricular arrhythmias are not as uncommon in children as previously believed, and four distinct phases of cardiac arrest can be delineated. Performance of, and technologic advances in, the treatment of cardiac arrest make this an exciting time in the field.

Importance of Both Early Reperfusion and Therapeutic Hypothermia in Limiting Myocardial Infarct Size Post-Cardiac Arrest in a Porcine Model.

OBJECTIVES: The aim of this study was to test the hypothesis that hypothermia and early reperfusion are synergistic for limiting infarct size when an acutely occluded coronary is associated with cardiac arrest. BACKGROUND: Cohort studies have shown that 1 in 4 post-cardiac arrest patients without ST-segment elevation has an acutely occluded coronary artery. However, many interventional cardiologists remain unconvinced that immediate coronary angiography is needed in these patients. METHODS: Thirty-two swine (mean weight 35 ± 5 kg) were randomly assigned to 1 of the following 4 treatment groups: group A, hypothermia and reperfusion; group B, hypothermia and no reperfusion; group C, no hypothermia and reperfusion; and group D, no hypothermia and no reperfusion. The left anterior descending coronary artery was occluded with an intracoronary balloon, and ventricular fibrillation was electrically induced. Cardiopulmonary resuscitation was begun after 4 min of cardiac arrest. Defibrillation was attempted after 2 min of cardiopulmonary resuscitation. Resuscitated animals randomized to hypothermia were rapidly cooled to 34°C, whereas those randomized to reperfusion had such after 45 min of left anterior descending coronary artery occlusion. RESULTS: At 4 h, myocardial infarct size was calculated. Group A had the smallest infarct size at 16.1 ± 19.6% (p < 0.05). Group C had an intermediate infarct size at 29.5 ± 20.2%, whereas groups B and D had the largest infarct sizes at 41.5 ± 15.5% and 41.1 ± 15.0%, respectively. CONCLUSIONS: Acute coronary occlusion is often associated with cardiac arrest, so treatment of resuscitated patients should include early coronary angiography for potential emergent reperfusion, while providing hypothermia for both brain and myocardial protection. Providing only early hypothermia, while delaying coronary angiography, is not optimal.

Prehospital risk factors of mortality and impaired consciousness after severe traumatic brain injury: an epidemiological study.

BACKGROUND: Severe traumatic brain injury (TBI) is a significant health concern and a major burden for society. The period between trauma event and hospital admission in an emergency department (ED) could be a determinant for secondary brain injury and early survival. The aim was to investigate the relationship between prehospital factors associated with secondary brain injury (arterial hypotension, hypoxemia, hypothermia) and the outcomes of mortality and impaired consciousness of survivors at 14 days. METHODS: A multicenter, prospective cohort study was performed in dedicated trauma centres of Switzerland. Adults with severe TBI (Abbreviated Injury Scale score of head region (HAIS) >3) were included. Main outcome measures were death and impaired consciousness (Glasgow Coma Scale (GCS) ≤13) at 14 days. The associations between risk factors and outcome were assessed with univariate and multivariate regression models. RESULTS: 589 patients were included, median age was 55 years (IQR 33, 70). The median GCS in ED was 4 (IQR 3-14), with abnormal pupil reaction in 167 patients (29.2%). Median ISS was 25 (IQR 21, 34). Three hundred seven patients sustained their TBI from falls (52.1%) and 190 from a road traffic accidents (32.3%). Median time from Out-of-hospital Emergency Medical Service (OHEMS) departure on scene to arrival in ED was 50 minutes (IQR 37-72); 451 patients had a direct admission (76.6%). Prehospital hypotension was observed in 24 (4.1%) patients, hypoxemia in 73 (12.6%) patients and hypothermia in 146 (24.8%). Prehospital hypotension and hypothermia (apart of age and trauma severity) was associated with mortality. Prehospital hypoxemia (apart of trauma severity) was associated with impaired consciousness; indirect admission was a protective factor. CONCLUSION: Mortality and impaired consciousness at 14 days do not have the same prehospital risk factors; prehospital hypotension and hypothermia is associated with mortality, and prehospital hypoxemia with impaired consciousness.