Spaite, Daniel W.

Objective: The 2010 AHA Guidelines stress the need for minimally interrupted, high quality CPR. We performed a prospective, before/after trial to determine if real-time audiovisual feedback (RTAVF) along with scenario-based training (SBT) would 1) achieve the 2010 CPR targets and 2) improve survival from OHCA. Methods: Data obtained from EMS care forms and defibrillators (E Series, ZOLL) from 2 EMS agencies (population base-500,000). Phase 1 (P1, before): 18 months of baseline data with the RTAVF mode disabled (9/08-3/10). Interventions: 1) Guideline-based SBT of ~450 EMTs, 2) RTAVF enabled, 3) EMT post-code debriefings. Phase 2 (P2, after): 8 months following implementation of interventions (5/10-12/10). For univariate analyses we used Fisher's exact test (proportions), t-test (means) or Kruskal-Wallis test (medians). To estimate odds ratios for survival to hospital discharge we used multivariable logistic regression and assessed final model diagnostics, fit, and discrimination. Results: The final analysis included 284 adult OHCAs (P1-176, P2-108). Mean age 65.4 years (SD ± 15.3) with 66.6% males. Quality measures improved significantly from P1 to P2: Median (Interquartile range) chest compression (CC) rate-121 CC/min (109-135) to 101 CC/min (100-106), p <0.001; CC depth-1.73 in. (1.42-1.97) to 2.09 in. (1.92-2.3), p <0.001; CC fraction-66.5% (59.3-75.9%) to 84.0% (77.8-88.7%), p <0.001. All-rhythms survival increased significantly (p=0.034) from P1 to P2 (18/176, 10.2% vs. 23/108, 19.4%), an absolute survival increase of 9.2% (95% CI: 0.5%-17.9%). Crude odds ratio for survival for P2 vs. P1 was 2.1 (95% CI: 1.1-4.2) and adjusted odds ratio was 5.8 (95% CI: 1.8-18.9), after controlling for confounders including age, sex, location, witnessed arrest, initial rhythm, and therapeutic hypothermia. Survival for arrests with a shockable rhythm was 27.7% (18/65) for P1 and 53.9% (14/26) for P2 (p=0.028). Conclusion: RTAVF combined with SBT was associated with a significant improvement in the proportion of compressions meeting the 2010 AHA Guidelines. This intervention was associated with a 90% relative increase in overall survival. We believe this is the first report to show an improvement in OHCA survival by achieving the 2010 AHA CPR Guidelines.

Background: High quality manual chest compressions (CC) can be achieved on scene during resuscitation of cardiac arrest patients, but manual CC quality can deteriorate during patient extrication and transport. The purpose of this study was to describe the effect on CC quality of an integrated manual/mechanical chest compression protocol developed to maintain CC quality and patient/provider safety throughout resuscitation. Methods: CC quality was monitored using a monitor with accelerometer-based CC sensing (E Series/X Series, ZOLL Medical) during the treatment of consecutive out-of-hospital cardiac arrest patients between 3/1/2013-4/30/2015. The EMS agency performed manual CC guided by real-time audiovisual feedback on scene but deployed the AutoPulse load-distributing band CC device (LDB, ZOLL Medical) in a choreographed manner for extrication and transport. The LDB was also placed prophylactically on patients after ROSC. Descriptive statistics are reported as median (IQR). Results: A total of 71 OHCA patients were treated (median age 58 yrs, 66 % male) of which 39 received only manual CC and 32 received both manual and LDB CCs (22 with LDB deployed during ongoing manual CC and 10 with LDB placed after ROSC). With real-time CC feedback, high quality CCs were performed [depth 2.38 in (2.17-2.64), rate 100.3 cpm (99.2-102.5), CC fraction 87.0% (83.8-89.5)]. For patients requiring transport, the LDB was started after 14.2 min (11.6-19.2) of manual CC and was placed with minimal interruptions- total of 27.5 sec (23-42) pause time in 2 minutes prior to LDB deployment. During transport, CC fraction remained high (91.7%; 89.3-95.4) with use of LDB. Seven of 10 patients prophylactically placed on the LDB rearrested, 3 rearrested during transport. Conclusion: A choreographed and rehearsed integrated chest compression protocol featuring both manual and mechanical compressions, allows for high quality resuscitation with minimal compression interruptions. Placement of a mechanical device on patients after ROSC may be beneficial as over two-thirds of patients in this study rearrested, one-third of which occurred during transport when delivery of manual compressions is difficult and potentially dangerous.

Background: Previous observational studies have demonstrated that outcomes after OHCA can be significantly improved with therapies such as mild therapeutic hypothermia and percutaneous coronary intervention (PCI). However, the optimal candidate and timing for PCI in OHCA remains unknown. This study aimed to assess the impact of emergent PCI on survival and neurological outcome after OHCA. Methods: This is a prospective observational study from a statewide OHCA database in Arizona. Patients included were greater than 18 years old who received CPR and were admitted to one of 34 recognized cardiac receiving centers. Patients who did not achieve ROSC, died within 2 hours of hospital arrival, and DNAR patients were excluded since the likelihood of PCI impacting outcome in these patients is questionable. An in-hospital post-arrest database, including PCI (Y/N), was linked with an Utstein-style OHCA database. Univariate and multivariate logistic regression were utilized to assess the association between PCI and survival to hospital discharge and neurological outcome. Results: During this study period (1-1-2011-12-31-2013), there were a total of 6,543 adult OHCA patients. After exclusions, 782 patients with suspected cardiac etiology OHCA were analyzed. The median age of patients was 64.0 years (Q1:54.0, Q3:73.0) and 70.2% were male. Among them 458 (58.6%) and 238 (30.4%) patients underwent the emergency coronary angiogram (CAG), and Primary PCI, respectively. Among PCI patients, the rate of survival to hospital discharge was 75.2%, vs. 60.4% for those without PCI (p<0.001) and good cerebral outcome (CPC 1-2) was found in 67.6%, vs. 44.3% of those without PCI (p<0.001). After adjusting for age, gender, initial rhythm, bystander CPR, and hypothermia, the Odds Ratio was 1.2 (95% CI:0.8-1.8) for survival and 2.8 (95% CI:1.5-5.1) for good neurologic outcome (CPC 1-2) among PCI patients. Conclusion: This study shows an association with emergent PCI and good neurologic outcome after OHCA. Further study is necessary to determine a potential causal relationship between PCI and outcome.

Background: Quantitative End-Tidal CO2 (PETCO2) measurement during cardiac arrest is recommended for monitoring the CPR quality to detect ROSC. While low ETC02 can reflect suboptimal CPR quality and increases in ETC02 are often associated with ROSC the significance of high values of PETCO2 without ROSC remain unclear. Objectives: To describe the population of OHCA victims with high PETCO2 (>50 mm Hg) during ongoing resuscitation including demographics, rhythm characteristics, occurrence of ROSC, the later occurrence of field termination of resuscitation and the presumed etiology. Methods: An observational analysis of adult OHCAs with available PETCO2 data occurring between Oct 2010 and Nov 2014 at two sites involved in the Save Hearts in Arizona Registry and Education (SHARE) quality improvement program. CPR and PETCO2 data were recorded using ZOLL E and X Series EMS monitors. PETCO2 is reported as the mean value for each minute. The cardiac rhythm and the presence of ROSC were determined for each minute using EMS provider reports, vital signs, ECG, and accelerometer data. The first recorded minute of PETCO2 and minutes with ROSC were excluded. Results: Study population included 654 OHCAs with PETCO2 data, 96 cases (58% male, age median 65 (IQR 54-75)) with at least 1 min of high PETCO2 in the absence of ROSC were identified. Of these, 31 (32%) had ROSC at least once during their resuscitation. Cases were of presumed cardiac etiology in 81 (84%), while 12% and 4% had presumed respiratory and other etiologies, respectively. A total of 322 minutes of PETCO2 >50 mm Hg in the absence of ROSC were identified. The mean PETC02 value was 67 (IQR 54-75). Of these 296 minutes (92%) occurred during PEA. Despite high PETCO2, resuscitation was terminated in the field in 21 (22%) patients. Only one subject survived to hospital discharge. Conclusions: In this observational study, high PETCO2 was frequently found during resuscitation without ROSC and PEA was the most common cardiac rhythm. Further study is warranted to determine the significance and possible reasons for this finding.

Background: Previous studies have described modest correlation between end-tidal CO 2 (ETCO 2 ) and CPR quality during resuscitation of cardiac arrest patients, but it is unclear whether ETCO 2 alone can indicate CPR quality. The present study investigated whether ETCO 2 adequately identifies the quality of CPR provided during out-of-hospital cardiac resuscitation. Methods: ETCO 2 was monitored with side-stream CO 2 (Philips/Respironics) and CPR quality measured with an accelerometer-based system (E Series, ZOLL Medical) during the treatment of consecutive adult OHCA patients with presumed cardiac etiology by 2 EMS agencies in the Arizona SHARE QI Program between 10/08-06/13. Minute-by-minute ETCO 2 and CPR quality were extracted. ETCO 2 values were log transformation to achieve approximate normality. Linear mixed effect models were fitted to use (transformed) ETCO 2 level to predict four CPR variables: chest compression (CC) depth, CC rate, CC release velocity (CCRV), and ventilation rate (VR). A random intercept for each case was included and a spatial power covariance structure assumed for measurements over time. Results: 230 subjects (median age 69 yrs, 69% male) with 1581 minutes of data were studied. Transformed ETCO 2 was significant for CC depth (p< 0.0001), CCRV (p=0.003) and VR (p<0.0001), but only explained 3.7%, 2.7%, and 10.0% of the total variance for these variables, respectively. Transformed ETCO 2 was not a significant predictor for CC rate (p=0.89). The Figure illustrates the overlap in CC depth over quartiles of ETCO 2 , demonstrating that any specific ETCO 2 level could be found over a wide range of CC depths. Conclusion: In this secondary analysis, ETCO 2 was not an independent indicator of CC rate but was a weak predictor for CC depth, CCRV and VR. These findings suggest that ETCO 2 may be not be an adequate substitute for CPR quality monitoring. Future studies should investigate how ETCO 2 and CPR quality monitoring can be used in conjunction to optimize CPR.

Background: Abnormal breathing, or “gasping,” frequently occurs during cardiac arrest and has been associated with increased survival. During 9-1-1 calls, early recognition of gasping may allow dispatchers to identify OHCA and to start CPR instructions promptly. Objective: To characterize lay rescuers’ descriptions of abnormal breathing during OHCA. Methods: 9-1-1 audio recordings of 4,279 confirmed OHCAs (10/10-7/14) in Arizona were reviewed by program personnel. Terms used by lay rescuers to describe victims’ breathing were recorded in a structured database. Results: Abnormal breathing (as opposed to “not breathing”) was described in 542/4279 (13%) calls. There were 623 verbal descriptions. A total of 50 different terms were used. However, the top 8 accounted for 83% and the remaining 42 descriptions (“Other”) comprised only 17% of all terms used. “Gasping” was the most commonly used term (30%; 187/623), followed by “snoring” (15%; 95/623; Figure). Conclusion: Lay rescuers used a wide variety of terms to describe abnormal breathing in documented OHCA. However, 8 terms accounted for 83% of descriptions. Familiarizing 9-1-1 telecommunicators with the most commonly used terms may improve the accuracy of recognition and hasten the identification of OHCA.

Background: Bystander CPR (BCPR) increases survival from OHCA yet is provided in a minority of cases. The AHA has promulgated guidelines on the provision of pre-arrival Telephone CPR (TCPR) instructions and measurement to increase the proportion of BCPR; however, the impact of those guidelines on survival is unknown. Objective: To describe the impact of a comprehensive bundle of 9-1-1 TCPR protocol, training, data collection, and feedback on BCPR and survival from OHCA across the state of Arizona. Methods: 9-1-1 audio recordings of confirmed OHCAs and suspected OHCAs (10/2010-6/2013) in 7 large 9-1-1 centers were reviewed using a standardized time-stamp methodology linked with EMS and hospital process and outcome data. There were 2343 pre-implementation cases (P1) and 2291 cases post-implementation of a bundle of care (P2) that included staff training and guideline-based protocol changes, data collection and feedback to providers. Univariate and multivariable analyses were used to assess outcomes between P1 and P2. Results: There were 2532 OHCAs [1232 P1, 1300 P2; 64% male, median age 62 (IQR: 47-74)]. 83% of cases were identified in P1 compared with 89% in P2 (p<0.001). The rate of telephone-assisted BCPR went from 44% in P1 to 62% in P2 (p<0.001). Time to beginning TCPR instructions decreased from a median of 144 sec (P1) to 126 in P2 (p<0.001). Time to first chest compression also decreased (P1: 178; P2: 155; p<0.001). Outcome data are currently available for 64% of confirmed OHCAs (1630 patient outcomes with 1619 neuro outcomes). Survival was significantly higher in P2 (11.2%) compared to P1 (7.9%; p=0.023), as was good neuro outcome (CPC-1 or 2: 7.7% P2 vs. 4.8% P1 p=0.018). After adjusting for witnessed arrest, shockable rhythms, age, and sex, both survival and good neuro outcome were still significantly higher in P2 vs. P1 [adjusted odds ratios: survival = 1.5 (95% 1.1-2.1); good neuro outcome = 1.7 (95% 1.1-2.6)]. Conclusion: The implementation of a comprehensive statewide TCPR bundle was associated with significant improvements in the rates of telephone-assisted BCPR, survival and good neurologic outcome after OHCA.

Background: Higher chest compression release velocity (CCRV) is associated with better outcomes after OHCA. Patient age and gender have been associated with variations in chest wall compliance and compressibility which may impact outcomes. Hypothesis: To evaluate the association between CCRV and OHCA patient age, weight, and gender. Methods: Observational study of prospectively collected OHCA quality improvement data in two suburban EMS agencies in Arizona between 10/1/2008 and 12/31/2016. Patient age and weight were categorized into quartiles for the analysis. CCRV was summarized at each level of the categorical variable by median and inter-quartile range (IQR), and was then compared between different levels by the Kruskal-Wallis test. Results: During the study period, 2,661 OHCA cases were treated. After exclusion criteria, 1,140 cases remained for analysis. Median duration of compressions was 8.70 minutes. Mean CCRV was negatively correlated with age and positively correlated with weight (Table). Male patients exhibited a greater mean CCRV compared to female patients [344.4 mm/s (IQR 307.3-384.6) vs. 331.5 (285.3-385.5), p=0.0133]. Conclusion: Patient characteristics including younger age, male gender, and increased weight were associated with a higher CCRV during OHCA resuscitation.

Background: Extended care facilities (ECFs) house unique patient populations with increased risk of out of hospital cardiac arrest (OHCA) and with unique, generally medically trained first responders initiating care prior to arrival of emergency medical services (EMS). However, little is known about bystander cardiopulmonary resuscitation (CPR) and resuscitation outcomes in this population. Our aim is to assess rate of CPR delivery prior to EMS arrival in cases of OHCA among residents ECFs across the state of Arizona. Methods: Cases of OHCA between 2016-2018, cared for by participating Arizona EMS agencies, were included if OHCA occurred at an ECF, age 18+, and was of presumed cardiac etiology. Association between survival status at discharge and bystander CPR was examined first by Chi-squared test then by logistic regression, which adjusted for important risk factors and potential confounders including: age, gender, witnessed arrest, shockable initial rhythm, and return of spontaneous circulation (ROSC) in EMS care. Results: There were 1,046 cases included in this study after excluding 32 cases with DNR and 11 with unknown bystander CPR status. Median patient age was 74 (interquartile range 64, 83). The overall rate of CPR prior to EMS arrival was 78.4% (95% CI, 75.8%, 80.9%). Survival to hospital discharge and survival with favorable neurologic outcome were not different between nursing home patients who received CPR prior to EMS arrival and those who did not [6.2% vs. 4.4% (p = 0.34) and 3.1% vs. 1.8% (p = 0.29)]. There was no statistically significant difference in the adjusted analysis. Conclusions: In this study population CPR was commonly delivered prior to EMS arrival. However, delivery of CPR prior to EMS arrival was not associated with survival to hospital discharge or favorable neurologic outcome. The lack of positive association between CPR prior to arrival and survival to hospital discharge may be related to comorbid factors present in ECF patients or differences in the time between collapse and initiation of CPR. Further study is needed to identify factors that might improve survival in this unique population.

Background Emergency 9‐1‐1 callers use a wide range of terms to describe abnormal breathing in persons with out‐of‐hospital cardiac arrest ( OHCA ). These breathing descriptors can obstruct the telephone cardiopulmonary resuscitation ( CPR ) process. Methods and Results We conducted an observational study of emergency call audio recordings linked to confirmed OHCA s in a statewide Utstein‐style database. Breathing descriptors fell into 1 of 8 groups (eg, gasping, snoring). We divided the study population into groups with and without descriptors for abnormal breathing to investigate the impact of these descriptors on patient outcomes and telephone CPR process. Callers used descriptors in 459 of 2411 cases (19.0%) between October 1, 2010, and December 31, 2014. Survival outcome was better when the caller used a breathing descriptor (19.6% versus 8.8%, P <0.0001), with an odds ratio of 1.63 (95% confidence interval, 1.17–2.25). After exclusions, 379 of 459 cases were eligible for process analysis. When callers described abnormal breathing, the rates of telecommunicator OHCA recognition, CPR instruction, and telephone CPR were lower than when callers did not use a breathing descriptor (79.7% versus 93.0%, P <0.0001; 65.4% versus 72.5%, P =0.0078; and 60.2% versus 66.9%, P =0.0123, respectively). The time interval between call receipt and OHCA recognition was longer when the caller used a breathing descriptor (118.5 versus 73.5 seconds, P <0.0001). Conclusions Descriptors of abnormal breathing are associated with improved outcomes but also with delays in the identification of OHCA . Familiarizing telecommunicators with these descriptors may improve the telephone CPR process including OHCA recognition for patients with increased probability of survival.