Part 5: Adult basic life support: 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

Optimal Chest Compression Position for Patients With a Single Ventricle During Cardiopulmonary Resuscitation

OBJECTIVES

Few studies have examined cardiopulmonary resuscitation for patients with congenital heart disease, although they are at a high risk of cardiac arrest. Therefore, this study investigated the optimal chest compression position in patients with a single ventricle while providing them with basic life support.

DESIGN

This is a retrospective study of patients with a single ventricle who are undergoing chest CT.

SETTING

Tertiary teaching children's hospital.

PATIENTS

A total of 185 patients with a single ventricle, including 73 patients before a bidirectional cavopulmonary shunt, 61 patients after a bidirectional cavopulmonary shunt, and 51 patients after the Fontan operation.

INTERVENTIONS

Chest CT scans were reviewed.

MEASUREMENTS AND MAIN RESULTS

Sternal length was defined as the distance from the suprasternal notch to the xiphisternal junction. The optimal level of external cardiac compression was defined as the level at which the cross-sectional area of the systemic ventricle was the largest. The distance from the suprasternal notch to this level over the sternum was calculated. The structures below the intermammary line, the lower half and the lower third of the sternum, and the optimal level were determined. The level with the largest cross-sectional area of the ventricle was approximately the lower fourth of the sternum in all surgical stages: 86.5% ± 4.9% of the sternal length from the suprasternal notch before bidirectional cavopulmonary shunt, 85.9% ± 4.8% after bidirectional cavopulmonary shunt, and 86.4% ± 6.3% after the Fontan operation. The liver was not identified at any level, whereas the ascending aorta was detected in 2.2%, 3.8%, and 24.9% at the level of the lower third of the sternum, the intermammary line, and the lower half of the sternum, respectively.

CONCLUSIONS

The optimal compression position in patients with a single ventricle is approximately 5-25% of the lower sternum. The optimal compression level for patients with a single ventricle is lower than that suggested in current guidelines for the normal population.

A flexible pressure sensor could correctly measure the depth of chest compression on a mattress

BACKGROUND

Feedback devices are used to improve the quality of chest compression (CC). However, reports have noted that accelerometers substantially overestimate depth when cardiopulmonary resuscitation (CPR) is performed on a soft surface. Here, we determined whether a flexible pressure sensor could correctly evaluate the depth CC performed on a mannequin placed on a mattress.

METHODS

Chest compression was performed 100 times/min by a compression machine on the floor or a mattress, and the depth of CC was monitored using a flexible pressure sensor (Shinnosukekun) and CPRmeter(™). The depth of machine-performed CC was consistently 5cm. We compared data from the feedback sensor with the true depth of CC using dual real-time auto feedback system that incorporated an infrared camera (CPR evolution(™)).

RESULTS

On the floor, the true depth of CC was 5.0±0.0cm (n=100), or identical to the depth of CC performed by the machine. The Shinnosukekun(™) measured a mean (±SD) CC depth of 5.0±0.1cm (n=100), and the CPRmeter(™) measured a depth of 5.0±0.2cm (n=100). On the mattress, the true depth of CC was 4.4±0.0cm (n=100). The Shinnosukekun(™) measured a mean CC depth of 4.4±0.0cm (n=100), and the CPRmeter(™) measured a depth of 4.7±0.1cm (n=100). The data of CPRmeter(™) were overestimated (P<.0001 between the true depth and the CPRmeter(™)-measured depth).

CONCLUSION

The Shinnosukekun(™) could correctly measure the depth of CC on a mattress. According to our present results, the flexible pressure sensor could be a useful feedback system for CC performed on a soft surface.

Part 3: Adult Basic Life Support and Automated External Defibrillation: 2015 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This review comprises the most extensive literature search and evidence evaluation to date on the most important international BLS interventions, diagnostics, and prognostic factors for cardiac arrest victims. It reemphasizes that the critical lifesaving steps of BLS are (1) prevention, (2) immediate recognition and activation of the emergency response system, (3) early high-quality CPR, and (4) rapid defibrillation for shockable rhythms. Highlights in prevention indicate the rational and judicious deployment of search-and-rescue operations in drowning victims and the importance of education on opioid-associated emergencies. Other 2015 highlights in recognition and activation include the critical role of dispatcher recognition and dispatch-assisted chest compressions, which has been demonstrated in multiple international jurisdictions with consistent improvements in cardiac arrest survival. Similar to the 2010 ILCOR BLS treatment recommendations, the importance of high quality was reemphasized across all measures of CPR quality: rate, depth, recoil, and minimal chest compression pauses, with a universal understanding that we all should be providing chest compressions to all victims of cardiac arrest. This review continued to focus on the interface of BLS sequencing and ensuring high-quality CPR with other important BLS interventions, such as ventilation and defibrillation. In addition, this consensus statement highlights the importance of EMS systems, which employ bundles of care focusing on providing high-quality chest compressions while extricating the patient from the scene to the next level of care. Highlights in defibrillation indicate the global importance of increasing the number of sites with public-access defibrillation programs. Whereas the 2010 ILCOR Consensus on Science provided important direction for the “what” in resuscitation (ie, what to do), the 2015 consensus has begun with the GRADE methodology to provide direction for the quality of resuscitation. We hope that resuscitation councils and other stakeholders will be able to translate this body of knowledge of international consensus statements to build their own effective resuscitation guidelines.

Integration of Attributes from Non-Linear Characterization of Cardiovascular Time-Series for Prediction of Defibrillation Outcomes

Objective

The timing of defibrillation is mostly at arbitrary intervals during cardio-pulmonary resuscitation (CPR), rather than during intervals when the out-of-hospital cardiac arrest (OOH-CA) patient is physiologically primed for successful countershock. Interruptions to CPR may negatively impact defibrillation success. Multiple defibrillations can be associated with decreased post-resuscitation myocardial function. We hypothesize that a more complete picture of the cardiovascular system can be gained through non-linear dynamics and integration of multiple physiologic measures from biomedical signals.

Materials and Methods

Retrospective analysis of 153 anonymized OOH-CA patients who received at least one defibrillation for ventricular fibrillation (VF) was undertaken. A machine learning model, termed Multiple Domain Integrative (MDI) model, was developed to predict defibrillation success. We explore the rationale for non-linear dynamics and statistically validate heuristics involved in feature extraction for model development. Performance of MDI is then compared to the amplitude spectrum area (AMSA) technique.

Results

358 defibrillations were evaluated (218 unsuccessful and 140 successful). Non-linear properties (Lyapunov exponent > 0) of the ECG signals indicate a chaotic nature and validate the use of novel non-linear dynamic methods for feature extraction. Classification using MDI yielded ROC-AUC of 83.2% and accuracy of 78.8%, for the model built with ECG data only. Utilizing 10-fold cross-validation, at 80% specificity level, MDI (74% sensitivity) outperformed AMSA (53.6% sensitivity). At 90% specificity level, MDI had 68.4% sensitivity while AMSA had 43.3% sensitivity. Integrating available end-tidal carbon dioxide features into MDI, for the available 48 defibrillations, boosted ROC-AUC to 93.8% and accuracy to 83.3% at 80% sensitivity.

Conclusion

At clinically relevant sensitivity thresholds, the MDI provides improved performance as compared to AMSA, yielding fewer unsuccessful defibrillations. Addition of partial end-tidal carbon dioxide (PetCO₂) signal improves accuracy and sensitivity of the MDI prediction model.

Internal Mammary Artery Injury Related to Chest Compressions in a Patient with Post-cardiac Arrest Syndrome

Although high-quality cardiopulmonary resuscitation (CPR) is essential for survival from cardiac arrest, chest compressions can also sometimes lead to life-threatening chest injuries. In addition, post-cardiac arrest syndrome patients often have coagulopathy due to therapeutic hypothermia, mechanical hemodynamic support, or both. Therefore, when progressive anemia and prolonged shock are detected in patients who have received CPR, identifying the cause of hemorrhagic shock is crucial. We herein present an interesting case of hemorrhagic shock due to an internal mammary artery injury secondary to CPR that was detected by computed tomography and invasive angiography.

The effect of mild induced hypothermia on outcomes of patients after cardiac arrest: a systematic review and meta-analysis of randomised controlled trials

INTRODUCTION

Mild induced hypothermia (MIH) is believed to reduce mortality and neurological impairment after out-of-hospital cardiac arrest. However, a recently published trial demonstrated that hypothermia at 33 °C did not confer a benefit compared with that of 36 °C. Thus, a systematic review and meta-analysis of randomised controlled trials (RCTs) was made to investigate the impact of MIH compared to controls on the outcomes of adult patients after cardiac arrest.

METHODS

We searched the following electronic databases: PubMed/MEDLINE, the Cochrane Library, Embase, the Web of Science, and Elsevier Science (inception to December 2014). RCTs that compared MIH with controls with temperature >34 °C in adult patients after cardiac arrest were retrieved. Two investigators independently selected RCTs and completed an assessment of the quality of the studies. Data were analysed by the methods recommended by the Cochrane Collaboration. Random errors were evaluated with trial sequential analysis.

RESULTS

Six RCTs, including one abstract, were included. The meta-analysis of included trials revealed that MIH did not significantly decrease the mortality at hospital discharge (risk ratio (RR) = 0.92; 95 % confidence interval (CI), 0.82-1.04; p = 0.17) or at 6 months or 180 days (RR = 0.94; 95 % CI, 0.73-1.21; p = 0.64), but it did reduce the mortality of patients with shockable rhythms at hospital discharge (RR = 0.74; 95 % CI, 0.59-0.92; p = 0.008) and at 6 months or 180 days. However, MIH can improve the outcome of neurological function at hospital discharge (RR = 0.80; 95 % CI, 0.64-0.98; p = 0.04) especially in those patients with shockable rhythm but not at 6 months or 180 days. Moreover, the incidence of complications in the MIH group was significantly higher than that in the control group. Finally, trial sequential analysis indicated lack of firm evidence for a beneficial effect.

CONCLUSION

The available RCTs suggest that MIH does not appear to improve the mortality of patients with cardiac arrest while it may have a beneficial effect for patients with shockable rhythms. Although MIH may result in some adverse events, it helped lead to better outcomes regarding neurological function at hospital discharge. Large-scale ongoing trials may provide data better applicable to clinical practice.

Load-distributing-band cardiopulmonary resuscitation for out-of-hospital cardiac arrest increases regional cerebral oxygenation: a single-center prospective pilot study

Background

Despite advances in therapeutic strategies and improved guidelines, morbidity and mortality rates for out-of-hospital cardiac arrest (OHCA) remain high. Especially, neurological prognosis is one of the most important problems even though brain protection therapy for patients with OHCA has improved greatly in recent years due to the development of emergency post-cardiac arrest interventions such as mild therapeutic hypothermia, early percutaneous coronary intervention, and extracorporeal cardiopulmonary resuscitation (CPR). Recently, cerebral regional oxygen saturation (rSO₂) has received attention as a method for evaluation of cerebral oxygenation. We have reported that conventional chest compression did not improve the rSO₂ of cardiac arrest patients if they did not achieve return of spontaneous circulation. It is, however, unclear whether a mechanical CPR device is helpful in improving rSO₂. The purpose of this study was to evaluate the effects of load-distributing-band CPR (LDB-CPR) on rSO₂.

Methods

In this prospective study, LDB-CPR was begun for OHCA with the AutoPulse^TM device on patient arrival at hospital. During mechanical CPR, rSO₂ values were recorded continuously from the forehead of the patients. CPR for patients with OHCA was performed according to the Japan Resuscitation Council Guidelines 2010 except for using the AutoPulse^TM instead of manual chest compression.

Results

From December 2012 to December 2013, 34 patients (mean age, 75.6 ± 12.8 years) with OHCA were included in this study. Duration of time from recognition of cardiac collapse to arrival to hospital was 31.0 ± 11.4 min. Compared with the rSO₂ value of 38.9 ± 0.7 % prior to starting LDB-CPR, rSO₂ values at 4, 8 and 12 minutes increased significantly after initiation of LDB-CPR (44.0 ± 0.9 %, 45.2 ± 0.8 %, and 45.5 ± 0.8 %, respectively, p < 0.05).

Conclusion

LDB-CPR significantly increased the rSO₂ of cardiac arrest patients during resuscitation.

Effect of prior cardiopulmonary resuscitation knowledge on compression performance by hospital providers

INTRODUCTION

The purpose of this study was to determine cardiopulmonary resuscitation (CPR) knowledge of hospital providers and whether knowledge affects performance of effective compressions during a simulated cardiac arrest.

METHODS

This cross-sectional study evaluated the CPR knowledge and performance of medical students and ED personnel with current CPR certification. We collected data regarding compression rate, hand placement, depth, and recoil via a questionnaire to determine knowledge, and then we assessed performance using 60 seconds of compressions on a simulation mannequin.

RESULTS

Data from 200 enrollments were analyzed by evaluators blinded to subject knowledge. Regarding knowledge, 94% of participants correctly identified parameters for rate, 58% for hand placement, 74% for depth, and 94% for recoil. Participants identifying an effective rate of ≥100 performed compressions at a significantly higher rate than participants identifying <100 (μ=117 vs. 94, p<0.001). Participants identifying correct hand placement performed significantly more compressions adherent to guidelines than those identifying incorrect placement (μ=86% vs. 72%, p<0.01). No significant differences were found in depth or recoil performance based on knowledge of guidelines.

CONCLUSION

Knowledge of guidelines was variable; however, CPR knowledge significantly impacted certain aspects of performance, namely rate and hand placement, whereas depth and recoil were not affected. Depth of compressions was poor regardless of prior knowledge, and knowledge did not correlate with recoil performance. Overall performance was suboptimal and additional training may be needed to ensure consistent, effective performance and therefore better outcomes after cardiopulmonary arrest.

Cardiac Arrest Resuscitation

Cardiac arrest is a dynamic disease that tests the multitasking and leadership abilities of emergency physicians. Providers must simultaneously manage the logistics of resuscitation while searching for the cause of cardiac arrest. The astute clinician will also realize that he or she is orchestrating only one portion of a larger series of events, each of which directly affects patient outcomes. Resuscitation science is rapidly evolving, and emergency providers must be familiar with the latest evidence and controversies surrounding resuscitative techniques. This article reviews evidence, discusses controversies, and offers strategies to provide quality cardiac arrest resuscitation.

Clinical risk factors for in-hospital adverse cardiovascular events after acute drug overdose

OBJECTIVES

It was recently demonstrated that adverse cardiovascular events (ACVE) complicate a high proportion of hospitalizations for patients with acute drug overdoses. The aim of this study was to derive independent clinical risk factors for ACVE in patients with acute drug overdoses.

METHODS

This prospective cohort study was conducted over 3 years at two urban university hospitals. Patients were adults with acute drug overdoses enrolled from the ED. In-hospital ACVE was defined as any of myocardial injury, shock, ventricular dysrhythmia, or cardiac arrest.

RESULTS

There were 1,562 patients meeting inclusion/exclusion criteria (mean age, 41.8 years; female, 46%; suicidal, 38%). ACVE occurred in 82 (5.7%) patients (myocardial injury, 61; shock, 37; dysrhythmia, 23; cardiac arrests, 22) and there were 18 (1.2%) deaths. On univariate analysis, ACVE risk increased with age, lower serum bicarbonate, prolonged QTc interval, prior cardiac disease, and altered mental status. In a multivariable model adjusting for these factors as well as patient sex and hospital site, independent predictors were: QTc > 500 msec (3.8% prevalence, odds ratio [OR] = 27.6), bicarbonate < 20 mEq/L (5.4% prevalence, OR = 4.4), and prior cardiac disease (7.1% prevalence, OR = 9.5). The derived prediction rule had 51.6% sensitivity, 93.7% specificity, and 97.1% negative predictive value, while presence of two or more risk factors had 90.9% positive predictive value.

CONCLUSIONS

The authors derived independent clinical risk factors for ACVE in patients with acute drug overdose, which should be validated in future studies as a prediction rule in distinct patient populations and clinical settings.

A performance improvement-based resuscitation programme reduces arrest incidence and increases survival from in-hospital cardiac arrest

BACKGROUND

Traditional resuscitation training models are inadequate to achieving and maintaining resuscitation competency. This analysis evaluates the effectiveness of a novel, performance improvement-based inpatient resuscitation programme.

METHODS

This was a prospective, before-and-after study conducted in an urban, university-affiliated hospital system. All inpatient adult cardiac arrest victims without an active Do Not Attempt Resuscitation order from July 2005 to June 2012 were included. The advanced resuscitation training (ART) programme was implemented in Spring 2007 and included a unique treatment algorithm constructed around the capabilities of our providers and resuscitation equipment, a training programme with flexible format and content including early recognition concepts, and a comprehensive approach to performance improvement feeding directly back into training. Our inpatient resuscitation registry and electronic patient care record were used to quantify arrest rates and survival-to-hospital discharge before and after ART programme implementation. Multiple logistic regression analysis was used to adjust for age, gender, location of arrest, initial rhythm, and time of day.

RESULTS

A total of 556 cardiac arrest victims were included (182 pre- and 374 post-ART). Arrest incidence decreased from 2.7 to 1.2 per 1000 patient discharges in non-ICU inpatient units, with no change in ICU arrest rate. An increase in survival-to-hospital discharge from 21 to 45% (p < 0.01) was observed following ART programme implementation. Adjusted odds ratios for survival-to-discharge (OR 2.2, 95% CI 1.4-3.4) and good neurological outcomes (OR 3.0, 95% CI 1.7-5.3) reflected similar improvements. Arrest-related deaths decreased from 2.1 to 0.5 deaths per 1000 patient discharges in non-ICU areas and from 1.5 to 1.3 deaths per 1000 patient discharges in ICU areas, and overall hospital mortality decreased from 2.2% to 1.8%.

CONCLUSIONS

Implementation of a novel, performance improvement-based inpatient resuscitation programme was associated with a decrease in the incidence of cardiac arrest and improved clinical outcomes.

Low compliance with the 2 minutes of uninterrupted chest compressions recommended in the 2010 International Resuscitation Guidelines

BACKGROUND

We aimed to analyze compliance with 2010 European guidelines' quality criteria for external chest compressions (ECC) during 2 minutes of uninterrupted cardiopulmonary resuscitation.

METHODS

Seventy-two healthy nurses and physicians trained in advanced cardiopulmonary resuscitation performed 2 uninterrupted minutes of ECC on a training manikin (Resusci Anne Advanced SkillTrainer; Laerdal Medical AS, Stavanger, Norway) that enabled us to measure the depth and rate of ECC. When professionals agreed to participate in the study, we recorded their age, body mass index (BMI), smoking habit, and their own subjective estimation of their physical fitness. To measure fatigue, we analyzed participants' heart rates, percentage of maximum tolerated heart rate (MHR), and subjective perception of their fatigue on a visual analog scale.

RESULTS

Nearly half (48.6%) the rescuers failed to achieve a minimum average ECC depth of 50 mm. Only 48.1% of ECCs fulfilled the 2010 guidelines' quality criteria; quality deteriorated mainly after the first minute. Poor ECC quality and deteriorating quality after the first minute were associated with BMI < 23 kg/m(2). Rescuers with BMI ≥ 23 kg/m(2) fulfilled the quality criteria throughout the 2 minutes, whereas those with BMI < 23 kg/m(2) fulfilled them for 80% of ECCs during the first minute, but for only 30% at the end of the 2 minutes.

CONCLUSIONS

Compliance with the 2010 guidelines' quality criteria is often poor, mainly due to lack of proper depth. The greater depth recommended in the 2010 guidelines with respect to previous guidelines requires greater force, so BMI < 23 kg/m(2) could hinder compliance. Limiting each rescuer's uninterrupted time doing ECC to 1 minute could help ensure compliance.

Fully automatic rhythm analysis during chest compression pauses

AIM

Chest compression artefacts impede a reliable rhythm analysis during cardiopulmonary resuscitation (CPR). These artefacts are not present during ventilations in 30:2 CPR. The aim of this study is to prove that a fully automatic method for rhythm analysis during ventilation pauses in 30:2 CPR is reliable an accurate.

METHODS

For this study 1414min of 30:2 CPR from 135 out-of-hospital cardiac arrest cases were analysed. The data contained 1942 pauses in compressions longer than 3.5s. An automatic pause detector identified the pauses using the transthoracic impedance, and a shock advice algorithm (SAA) diagnosed the rhythm during the detected pauses. The SAA analysed 3-s of the ECG during each pause for an accurate shock/no-shock decision.

RESULTS

The sensitivity and PPV of the pause detector were 93.5% and 97.3%, respectively. The sensitivity and specificity of the SAA in the detected pauses were 93.8% (90% low CI, 90.0%) and 95.9% (90% low CI, 94.7%), respectively. Using the method, shocks would have been advanced in 97% of occasions. For patients in nonshockable rhythms, rhythm reassessment pauses would be avoided in 95.2% (95% CI, 91.6-98.8) of occasions, thus increasing the overall chest compression fraction (CCF).

CONCLUSION

An automatic method could be used to safely analyse the rhythm during ventilation pauses. This would contribute to an early detection of refibrillation, and to increase CCF in patients with nonshockable rhythms.

Introduction of performance coaching during cardiopulmonary resuscitation improves compression depth and time to defibrillation in out-of-hospital cardiac arrest

INTRODUCTION

Quality cardiopulmonary resuscitation (CPR) and timely defibrillation are associated with increasing survival to hospital discharge from out-of-hospital cardiac arrest (OHCA). The objective of this study was to demonstrate that performance coaching during an OHCA would improve compression depth and time to defibrillation (TTD).

METHODS

This study was conducted in a single emergency medical services (EMS) agency and utilized data collected from 815 patients treated between 1/1/2012 and 12/31/2013. The intervention used multiple Plan-Do-Study-Act (PDSA) cycles to train fire captains to translate performance data into active direction. Testing began in simulation with small-scale expansions prior to system-wide implementation. Performance metrics included average (reported as a percentage) and actual compression depth (reported in millimeters), and TTD (an average in seconds). Analysis was conducted using Xbar and S control charts with standard assessment of special cause for performance data. A statistical shift was seen in means and standard deviations for both depth metrics.

RESULTS

Average depth of compressions improved from 69.8% (SD=28.0%) to 80.4 (SD=21.8%). Depth of compressions delivered increased from 43.6mm (SD=8.2mm) to 47.2mm (SD=8.1mm). Analysis of the S charts indicates a statistical shift in process variation for TTD.

CONCLUSION

Early results indicate that utilization of a CPR coach during OHCA improves compression depth and TTD. Further data are needed to assess sustainability.

What is the optimal chest compression depth during out-of-hospital cardiac arrest resuscitation of adult patients?

BACKGROUND

The 2010 American Heart Association guidelines suggested an increase in cardiopulmonary resuscitation compression depth with a target >50 mm and no upper limit. This target is based on limited evidence, and we sought to determine the optimal compression depth range.

METHODS AND RESULTS

We studied emergency medical services-treated out-of-hospital cardiac arrest patients from the Resuscitation Outcomes Consortium Prehospital Resuscitation Impedance Valve and Early Versus Delayed Analysis clinical trial and the Epistry-Cardiac Arrest database. We calculated adjusted odds ratios for survival to hospital discharge, 1-day survival, and any return of circulation. We included 9136 adult patients from 9 US and Canadian cities with a mean age of 67.5 years, mean compression depth of 41.9 mm, and a return of circulation of 31.3%, 1-day survival of 22.8%, and survival to hospital discharge of 7.3%. For survival to discharge, the adjusted odds ratios were 1.04 (95% CI, 1.00-1.08) for each 5-mm increment in compression depth, 1.45 (95% CI, 1.20-1.76) for cases within 2005 depth range (>38 mm), and 1.05 (95% CI, 1.03-1.08) for percentage of minutes in depth range (10% change). Covariate-adjusted spline curves revealed that the maximum survival is at a depth of 45.6 mm (15-mm interval with highest survival between 40.3 and 55.3 mm) with no differences between men and women.

CONCLUSIONS

This large study of out-of-hospital cardiac arrest patients demonstrated that increased cardiopulmonary resuscitation compression depth is strongly associated with better survival. Our adjusted analyses, however, found that maximum survival was in the depth interval of 40.3 to 55.3 mm (peak, 45.6 mm), suggesting that the 2010 American Heart Association cardiopulmonary resuscitation guideline target may be too high.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00394706.

Effectiveness of prehospital Magill forceps use for out-of-hospital cardiac arrest due to foreign body airway obstruction in Osaka City

BACKGROUND

Although foreign body airway obstruction (FBAO) accounts for many preventable unintentional accidents, little is known about the epidemiology of FBAO patients and the effect of forceps use on those patients. This study aimed to assess characteristics of FBAO patients transported to hospitals by emergency medical service (EMS) personnel, and to verify the relationship between prehospital Magill forceps use and outcomes among out-of-hospital cardiac arrests (OHCA) patients with FBAO.

METHODS

We retrospectively reviewed ambulance records of all patients who suffered FBAO, and were treated by EMS in Osaka City from 2000 through 2007, and assessed the characteristics of those patients. We also performed a multivariate logistic-regression analysis to assess factors associated with neurologically favorable survival among bystander-witnessed OHCA patients with FBAO in larynx or pharynx.

RESULTS

A total of 2,354 patients suffered from FBAO during the study period. There was a bimodal distribution by age among infants and old adults. Among them, 466 (19.8%) had an OHCA when EMS arrived at the scene, and 344 were witnessed by bystanders. In the multivariate analysis, Magill forceps use for OHCA with FBAO in larynx or pharynx was an independent predictor of neurologically favorable survival (16.4% [24/146] in the Magill forceps use group versus 4.3% [4/94] in the non-use group; adjusted odds ratio, 3.96 [95% confidence interval, 1.21-13.00], p = 0.023).

CONCLUSIONS

From this large registry in Osaka, we revealed that prehospital Magill forceps use was associated with the improved outcome of bystander-witnessed OHCA patients with FBAO.

A reliable method for rhythm analysis during cardiopulmonary resuscitation

Interruptions in cardiopulmonary resuscitation (CPR) compromise defibrillation success. However, CPR must be interrupted to analyze the rhythm because although current methods for rhythm analysis during CPR have high sensitivity for shockable rhythms, the specificity for nonshockable rhythms is still too low. This paper introduces a new approach to rhythm analysis during CPR that combines two strategies: a state-of-the-art CPR artifact suppression filter and a shock advice algorithm (SAA) designed to optimally classify the filtered signal. Emphasis is on designing an algorithm with high specificity. The SAA includes a detector for low electrical activity rhythms to increase the specificity, and a shock/no-shock decision algorithm based on a support vector machine classifier using slope and frequency features. For this study, 1185 shockable and 6482 nonshockable 9-s segments corrupted by CPR artifacts were obtained from 247 patients suffering out-of-hospital cardiac arrest. The segments were split into a training and a test set. For the test set, the sensitivity and specificity for rhythm analysis during CPR were 91.0% and 96.6%, respectively. This new approach shows an important increase in specificity without compromising the sensitivity when compared to previous studies.

Motion generated in the unstable upper cervical spine during head tilt-chin lift and jaw thrust maneuvers

BACKGROUND CONTEXT

Although it is essential to maintain a secure airway in a trauma patient, it is also critical to protect the potentially injured cervical spine. It has previously been suggested that the jaw thrust maneuver be used in place of the head tilt-chin lift in the suspected spine-injured patient.

PURPOSE

We sought to examine whether the jaw thrust was in fact safer to use in the setting of an unstable upper cervical spine injury.

METHODS

Unstable, dissociative C1-C2 injuries were surgically created in nine fresh, lightly embalmed human cadaver specimens. An electromagnetic motion analysis device was used to assess the amount of angular and linear motion with sensors placed above and below the injured segment. Measurements were recorded during execution of the two airway maneuvers. Trials were performed both with and without a cervical immobilization collar in place.

RESULTS

There was almost twice as much angular motion in all planes when performing a head tilt-chin lift as compared with the jaw thrust, and this was statistically significant (p<.013). In addition, there was more displacement at the injured level with a head tilt-chin lift as compared with the jaw thrust. This was statistically significant for axial displacement and anteroposterior translation (p=.003 for both), and approached significance for mediolateral translation (p=.056).

CONCLUSIONS

The jaw thrust maneuver results in less motion at an unstable C1-C2 injury as compared with the head tilt-chin lift maneuver. We therefore recommend the use of the jaw thrust to improve airway patency in the trauma patient with suspected cervical spine injury.

A case of survival after cardiac arrest and 3½ hours of resuscitation

Although survival rates after cardiac arrest remain low, new techniques are improving patients' outcomes. We present the case of a 40-year-old man who survived a cardiac arrest that lasted approximately 3½ hours. Resuscitation was performed with strict adherence to American Heart Association/American College of Cardiology Advanced Cardiac Life Support guidelines until bedside extracorporeal membrane oxygenation could be placed. A hypothermia protocol was initiated immediately afterwards. The patient had a full neurologic recovery and was bridged from dual ventricular assist devices to a total artificial heart. On hospital day 160, he underwent orthotopic heart and cadaveric kidney transplantation. On day 179, he was discharged from the hospital in ambulatory condition. To our knowledge, this is the only reported case in which a patient survived with good neurologic outcomes after a resuscitation that lasted as long as 3½ hours. Documented cases of resuscitation with good recovery after prolonged arrest give hope for improved overall outcomes in the future.

Racial susceptibility for QT prolongation in acute drug overdoses

BACKGROUND AND PURPOSE

QT prolongation independently predicts adverse cardiovascular events in suspected poisoning. We aimed to evaluate the association between race and drug-induced QT prolongation for patients with acute overdose.

METHODS

This was a cross-sectional observational study at two urban teaching hospitals. Consecutive adult ED patients with acute drug overdose were prospectively enrolled over a two year period. The primary outcome, long-QT, was defined using standard criteria: QTc>470 ms in females and>460 ms in males. The association between race and drug-induced QT prolongation was tested, considering several confounding variables.

RESULTS

In 472 patients analyzed (46% female, mean age 42.3), QT prolongation occurred in 12.7%. Blacks had two-fold increased odds of drug-induced QT prolongation (OR 2.01, CI 1.03-3.91) and Hispanics had 48% decreased odds of drug-induced QT prolongation (OR 0.52, CI 0.29-0.94).

CONCLUSIONS

We found significant racial susceptibility to drug-induced QT prolongation in this large urban study of acute overdoses.

A systematic review and pooled analysis of CPR-associated cardiovascular and thoracic injuries

OBJECTIVE

The incidence of thoracic injuries resulting from cardiopulmonary resuscitation (CPR) is not well characterized. We describe a case in which a CPR-associated atrial rupture was identified with ultrasound and successfully managed in the intensive care unit with a bedside thoracotomy and atrial repair. We then describe a systematic review with pooled data analysis of CPR-associated cardiovascular, pulmonary, pleural, and thoracic wall injuries.

DATA SOURCES

PubMed, Scopus, EMBASE, and Web of Science were searched to identify relevant published studies. Unpublished studies were identified by searching the Australian and New Zealand Clinical Trials Registry, World Health Organization International Clinical Trials Registry Platform, Cochrane Library, ClinicalTrials.gov, Current Controlled Trials, and Google.

STUDY SELECTION

Inclusion criteria for the pooled analysis were any clinical or autopsy study in which (a) patients underwent cardiopulmonary resuscitation, (b) chest compressions were administered either manually or with the assistance of active compression-decompression devices, and (c) autopsy or dedicated imaging assessments were conducted to identify complications. Exclusion criteria for the pooled analysis were pre-clinical studies, case reports and abstracts.

DATA EXTRACTION

Nine-hundred twenty-eight potentially relevant references were identified. Twenty-seven references met inclusion criteria.

DATA SYNTHESIS

A systematic review of the literature is provided with pooled data analysis.

CONCLUSIONS

The incidence of reported CPR-associated cardiovascular and thoracic wall injuries varies widely. CPR with active compression-decompression devices has a higher reported incidence of cardiopulmonary injuries. Bedside ultrasound may be a useful adjunct to assess and risk-stratify patients to identify serious or life-threatening CPR-associated injuries.

Rhythm analysis during cardiopulmonary resuscitation: past, present, and future

Survival from out-of-hospital cardiac arrest depends largely on two factors: early cardiopulmonary resuscitation (CPR) and early defibrillation. CPR must be interrupted for a reliable automated rhythm analysis because chest compressions induce artifacts in the ECG. Unfortunately, interrupting CPR adversely affects survival. In the last twenty years, research has been focused on designing methods for analysis of ECG during chest compressions. Most approaches are based either on adaptive filters to remove the CPR artifact or on robust algorithms which directly diagnose the corrupted ECG. In general, all the methods report low specificity values when tested on short ECG segments, but how to evaluate the real impact on CPR delivery of continuous rhythm analysis during CPR is still unknown. Recently, researchers have proposed a new methodology to measure this impact. Moreover, new strategies for fast rhythm analysis during ventilation pauses or high-specificity algorithms have been reported. Our objective is to present a thorough review of the field as the starting point for these late developments and to underline the open questions and future lines of research to be explored in the following years.

Clinical characteristics and vital and functional prognosis of out-of-hospital cardiac arrest survivors admitted to five cardiac intensive care units

INTRODUCTION AND OBJECTIVES

Survivors of out-of-hospital cardiac arrest constitute an increasing patient population in cardiac intensive care units. Our aim was to characterize these patients and determine their vital and functional prognosis in accordance with the latest evidence.

METHODS

A multicenter, prospective register was constructed with information from patients admitted to 5 cardiac intensive care units from January 2010 through January 2012 with a diagnosis of resuscitated out-of-hospital cardiac arrest. The information included clinical status, cardiac arrest characteristics, in-hospital course, and vital and neurologic status at discharge and at 6 months.

RESULTS

A total of 204 patients were included. In 64% of cases, a first shockable rhythm was identified. The time to return of spontaneous circulation was 29 (18) min. An etiologic diagnosis was made in 86% of patients; 44% were discharged with no neurologic sequelae; 40% died in the hospital. At 6 months, 79% of survivors at discharge were still alive and neurologically intact with minimal sequelae. Short resuscitation time, first recorded rhythm, pH on admission >7.1, absence of shock, and use of hypothermia were the independent variables associated with a good neurologic prognosis.

CONCLUSIONS

Half the patients who recovered from out-of-hospital cardiac arrest had good neurologic prognosis at discharge, and 79% of survivors were alive and neurologically intact after 6 months of follow-up.

An institutionwide approach to redesigning management of cardiopulmonary resuscitation

BACKGROUND

Despite widespread training in basic life support (BLS) and advanced cardiovascular life support (ACLS) among hospital personnel, the likelihood of survival from in-hospital cardiac arrests remains low. In 2006 a university-affiliated tertiary medical center initiated a cardiopulmonary (CPR) resuscitation redesign project. REDESIGNING THE HOSPITAL'S RESUSCITATION SYSTEM: The CPR Committee developed the interventions on the basis of a large-scale view of the process of delivering BLS and ACLS, identification of key decision nodes and actions, and compartmentalization of specific functions. It was proposed that arrest management follow a steady progression in a two-layer scheme from BLS to ACLS. Handouts describing team structure and specific roles were given to all code team providers and house staff at the start of their month-long rotations. To further increase role clarity and team organization, daily morning and evening meetings of the arrest team were instituted. Site-specific BLS training, on-site ACLS refresher training, and defibrillator training were initiated. Project elements also included use of unannounced mock codes to provide system oversight; preparation and distribution of cognitive aids (printed algorithms, dosing guides, and other checklists to ensure compliance with ACLS protocols), identification of patients who may be unstable or a source of concern, event review and analysis of arrests and other critical events, and a CPR website.

CONCLUSION

A mature hospital-based resuscitation system should include definition of arrest trends and resuscitation needs, development of local methods for approaching the arresting patient, an emphasis on prevention, establishment of training programs tailored to meet specific hospital needs, system examination and oversight, and administrative processes that maximize interaction between all components.