Kern, Karl B.

Background: The 2010 AHA Guidelines state rescuers should perform chest compressions (CCs) of at least 2 inches in depth for adult cardiac arrest patients. Although the pediatric guidelines recommend adjustment of CC depth based upon anteroposterior chest dimension, there is no such recommendation for adults. Purpose: To determine 1) whether prehospital providers intuitively vary CC depth in adults according to patient size and 2) whether implementation of real-time audiovisual CPR feedback (RTAVF) impacts weight/CC depth variation. Methods: CC quality data were prospectively collected prior to (9/08-4/10; Pre-feedback) and after (5/10-12/10; Post-feedback) implementation of an RTAVF system (ZOLL Medical, Chelmsford MA) from 3 EMS agencies. The RTAVF includes a visual display of absolute CC depth and gives audio prompts when depth is outside of the Guideline-recommended range. Among 363 cases of adult, non-traumatic out-of-hospital cardiac arrest (OHCA), body weight was estimated by EMS in 249 patients (study group; 66%). CPR quality data were available for all cases via code review software. Results: 168 Pre-feedback and 81 Post-feedback study group cases (mean 64±16 years, 68% male). Mean estimated body weight was 201 lbs (quartiles 161, 231; range 70-451) and was not different between groups. CC depth increased significantly with RTAVF use (Pre-feedback = 1.77, 95% confidence interval [CI]:1.71-1.83 in.; Post-feedback = 2.10, CI: 2.04-2.15 in.; p<0.001). CC depth did not vary significantly by patient gender or age (p>0.4). Multivariate linear regression (r 2 =0.23, p<0.001 for model) revealed a significant increase in CC depth with estimated weight in both periods (0.07in/50lbs, p<0.001) after controlling for the presence of RTAVF. RTAVF was not an effect-modifier of the relationship between estimated weight and CC depth (p-value for interaction term=0.4). Conclusion: Although not specifically recommended in the 2010 AHA Guidelines for adults, rescuers may instinctively and/or intentionally adjust CC depth according to patient size. In this setting, weight/CC depth adjustments occurred both without and with real-time feedback. Follow-up studies are needed to determine the potential effect of size-adjusted CC depth on patient outcome.

BACKGROUND: For sudden collapse from out-of-hospital cardiac arrest (OHCA) in adults, bystander chest compression-only CPR (COCPR) results in equivalent or better survival compared with conventional CPR with rescue breathing. However, patients who arrest from a non-cardiac cause may also receive COCPR even though rescue breathing might benefit them. We sought to determine whether lay rescuers appropriately provided COCPR or conventional CPR depending on the suspected etiology of OHCA. METHODS: Analysis of a statewide, Utstein-style registry of adult OHCA during a large-scale campaign endorsing COCPR for adults who suddenly collapse. The relationship between bystander CPR (both COCPR and conventional CPR), presumed arrest etiology, and survival to hospital discharge were evaluated. Means and 95% confidence intervals (CI) were calculated. FINDINGS: A total of 7,652 adult OHCAs not witnessed by EMS were analyzed from 10/04 to 09/10. After exclusion of non-lay bystanders and arrests in medical facilities, presumed cardiac etiology and non-cardiac etiology OHCA totaled 4,913 and 1,202, respectively. The presumed specific non-cardiac etiologies were non-cardiopulmonary (e.g. overdose, suicide, subarachnoid hemorrhage) (57%), trauma (27%), and respiratory (16%). All-rhythm survival was 7.0% (CI: 6.3 - 7.8) for cardiac etiologies and 3.3% (CI: 2.3 - 4.3) for non-cardiac (p<0.001). Bystander CPR was provided for 33% (CI: 31.4 - 34.1) of victims with presumed cardiac causes versus 28% (CI: 25.6 - 30.7) for non-cardiac causes (p=0.002). Presumed respiratory causes of OHCA had a much lower proportion of COCPR (8.3%, CI: 4.4 - 12.2) than cardiac causes (18.0%, CI: 16.9 - 19.1, p<0.001). Survival for non-cardiac cases was: 4.4% (CI 0.9 - 7.8) for conventional CPR, 3.5% (CI: 0.9 - 6.0) for COCPR, and 3.1% (CI: 2.0 - 4.3) for no CPR (p = 0.66). CONCLUSIONS: In the setting of a large-scale, statewide public health campaign endorsing lay rescuer COCPR for adults who suddenly collapse and are not breathing normally, bystanders were much less likely to perform COCPR on OHCA victims who might benefit from rescue breathing. Furthermore, when COCPR was performed on presumed non-cardiac cause arrest victims, there was no demonstrable negative impact on survival.

Abstract IntroductionSimulation technology has an established role in teaching technical skills to cardiology fellows, but their impact on teaching trainees to interpret coronary angiographic (CA) images has not been systematically studied. The aim of this randomized controlled study was to test whether structured simulation training in addition to traditional methods would improve CA image interpretation skills in a group of novices to advanced medical trainees.MethodsWe prospectively randomized 105 subjects comprising of medical students (N=20), residents (N=68) and fellows (N=17) from the University of Arizona. Subjects were randomized into a simulation training group which received simulation training in addition to didactic teaching (n=53) and a control training group which received didactic teaching alone (n=52). The change in pre and post-test score (delta score) was analyzed by a two-way ANOVA for education status and training arm.ResultsSubjects improved in their post-test scores with a mean change of 4.6 ± 4.0 points. Subjects in the simulation training arm had a higher delta score compared to control (5.4 ± 4.2 versus 3.8 ± 3.7, p=0.04), with greatest impact for residents (6.6 ± 4.0 versus 3.5 ± 3.4) with a p=0.02 for interaction of training arm and education status.ConclusionsSimulation training complements traditional methods to improve CA interpretation skill, with greatest impact on novice trainees. This highlights the importance of incorporating high-fidelity simulation training early in cardiovascular fellowship curricula.

Background: The benefit of emergency coronary angiography after resuscitation from out-of-hospital cardiac arrest is uncertain for patients without ST-segment elevation. The aim of this randomized trial was to evaluate the efficacy and safety of early coronary angiography and to determine the prevalence of acute coronary occlusion in resuscitated patients with out-of-hospital cardiac arrest without ST-segment elevation. Methods: Adult (>18 years) comatose survivors without ST-segment elevation after resuscitation from out-of-hospital cardiac arrest were prospectively randomized in a 1:1 fashion under exception to informed consent regulations to early coronary angiography versus no early coronary angiography in this multicenter study. Early angiography was defined as ≤120 minutes from arrival at the percutaneous coronary intervention–capable facility. The primary end point was a composite of efficacy and safety measures, including efficacy measures of survival to discharge, favorable neurologic status at discharge (Cerebral Performance Category score ≤2), echocardiographic measures of left ventricular ejection fraction >50%, and a normal regional wall motion score of 16 within 24 hours of admission. Adverse events included rearrest, pulmonary edema on chest x-ray, acute renal dysfunction, bleeding requiring transfusion or intervention, hypotension (systolic arterial pressure ≤90 mm Hg), and pneumonia. Secondary end points included the incidence of culprit vessels with acute occlusion. Results: The study was terminated prematurely before enrolling the target number of patients. A total of 99 patients were enrolled from 2015 to 2018, including 75 with initially shockable rhythms. Forty-nine patients were randomized to early coronary angiography. The primary end point of efficacy and safety was not different between the 2 groups (55.1% versus 46.0%; P =0.64). Early coronary angiography was not associated with any significant increase in survival (55.1% versus 48.0%; P =0.55) or adverse events (26.5% versus 26.0%; P =1.00). Early coronary angiography revealed a culprit vessel in 47%, with a total of 14% of patients undergoing early coronary angiography having an acutely occluded culprit coronary artery. Conclusions: This underpowered study, when considered together with previous clinical trials, does not support early coronary angiography for comatose survivors of cardiac arrest without ST elevation. Whether early detection of occluded potential culprit arteries leads to interventions that improve outcomes requires additional study. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02387398.

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.