Prehospital Administration of Norepinephrine and Epinephrine for Shock after Resuscitation from Cardiac Arrest.

INTRODUCTION: Shock after resuscitation from out-of-hospital cardiac arrest (OHCA) is often treated with vasopressors. We examined whether infusion of epinephrine versus norepinephrine was associated with prehospital rearrest and neurologically favorable survival among OHCA patients. METHODS: This retrospective study included OHCA cases in Seattle, Washington from 2014-2021 who had return of spontaneous circulation (ROSC) followed by vasopressor infusion. Our primary exposure was infusion of epinephrine or norepinephrine. Our primary outcome was prehospital rearrest. Secondary outcomes included survival and neurologically favorable outcome (Cerebral Performance Category score of 1 or 2). We used multivariable logistic regression to test associations between exposures and outcomes adjusting for key covariates. RESULTS: Of 451 OHCA patients with ROSC followed by vasopressor infusion, 253 (56%) received norepinephrine and 198 (44%) received epinephrine infusions. Those who received epinephrine were older (median 66 [interquartile ranges {IQR} 53-79] vs 63 [IQR 47-75] years), but otherwise had similar baseline characteristics. Patients who received epinephrine were twice as likely to rearrest (55% vs 25%). After adjustment, the difference in rearrest rates between epinephrine and norepinephrine persisted (OR 3.28, 95%CI 2.25-5.08), and the odds of pulses at hospital arrival were lower in the epinephrine group (OR 0.52 95%CI 0.32-0.83). After adjustment, there was no difference in neurologically favorable survival, survival to hospital admission, or survival to discharge. CONCLUSION: Patients who received epinephrine infusions after ROSC suffered prehospital rearrest more frequently than those who received norepinephrine. Survival and neurological status at hospital discharge were similar. Future trials should examine the optimal approach to hemodynamic management for post-OHCA shock.

Comparison of Intubating Conditions with Succinylcholine Versus Rocuronium in the Prehospital Setting.

OBJECTIVE: Rapid sequence intubation (RSI) is frequently performed by emergency medical services (EMS). We investigated the relationship between succinylcholine and rocuronium use and time until first laryngoscopy attempt, first-pass success, and Cormack-Lehane (CL) grades. METHODS: We included adult patients for whom prehospital RSI was attempted from July 2015 through June 2022 in a retrospective, observational study with pre-post analysis. Timing was verified using recorded defibrillator audio in addition to review of continuous ECG, pulse oximetry, and end-tidal carbon dioxide waveforms. Our primary exposure was neuromuscular blocking agent (NMBA) used, either rocuronium or succinylcholine. Our prespecified primary outcome was the first attempt Cormack-Lehane view. Key secondary outcomes were first laryngoscopy attempt success rate, timing from NMBA administration to first attempt, number of attempts, and hypoxemic events. RESULTS: Of 5,179 patients in the EMS airway registry, 1,475 adults received an NMBA while not in cardiac arrest. Cormack-Lehane grades for succinylcholine and rocuronium were similar: grade I (64%, 59% [95% CI 0.64-1.09]), grade II (16%, 21%), grade III (18%, 16%), grade IV (3%, 3%). The median interval from NMBA administration to start of the first attempt was 57 s for succinylcholine and 83 s for rocuronium (mean difference 28 [95% CI 20-36] seconds). First attempt success was 84% for succinylcholine and 83% for rocuronium. Hypoxemic events were present in 25% of succinylcholine cases and 23% of rocuronium cases. CONCLUSIONS: Prehospital use of either rocuronium or succinylcholine is associated with similar Cormack-Lehane grades, first-pass success rates, and rates of peri-intubation hypoxemia.

Burnout and Workplace Incivility Among Emergency Medical Services Practitioners: A Preliminary Report.

OBJECTIVE: Burnout has detrimental consequences for health care organizations, clinicians, and the quality of care that patients receive. Prior work suggests that workplace incivility (negative interpersonal acts) contributes to burnout. While workplace incivility is linked to EMS practitioner job dissatisfaction, absenteeism, and planned attrition, the relationship between workplace incivility and burnout has not been evaluated among EMS practitioners. This study aimed to characterize the prevalence and association of burnout and workplace incivility among EMS practitioners. METHODS: A cross-sectional survey of EMS personnel in King County, Washington was performed in January to March of 2021 with burnout as the primary outcome and workplace incivility as a secondary outcome. Multivariable logistic regression was used to evaluate associations between outcomes and EMS practitioner factors that included age, sex, race/ethnicity, years of EMS experience, and current job role. RESULTS: 835 completed surveys were received (response rate 25%). The prevalence of burnout was 39.2%. Women were more likely to have burnout than men (59.3% vs. 33.7%, aOR 2.2, 95% CI 1.3-3.7). Workplace incivility was experienced weekly by 32.1% of respondents, with women more likely to experience incivility compared to men (41.9% vs. 27.2%, aOR 2.0, 95% CI 1.2-3.3). Respondents who experienced frequent workplace incivility were more likely to have burnout than those who did not experience frequent incivility (61.9% vs. 38.1%, OR 4.0, 95% CI 3.0-5.5). CONCLUSIONS: The prevalence of burnout and workplace incivility were concerning among EMS practitioners, with women more likely to experience both compared to men. EMS practitioners who experienced frequent workplace incivility were also more likely to have burnout than those who did not experience frequent incivility.

Providing whole blood for an urban paramedical ambulance system.

INTRODUCTION: Hemorrhage is the second leading cause of death among urban trauma patients, and the provision of prehospital blood-based resuscitation can be lifesaving. We developed an efficient system to support blood-based resuscitation by an urban advanced life support ambulance system. METHODS: We worked with our state health department for permission for fire department paramedics to initiate blood transfusion and built protocols for field whole blood resuscitation. Our regional trauma center transfusion service provided 2 units of O positive, low-titer, leukoreduced whole blood in an internally monitored and sealed ice box weighing 10 pounds to the fire department paramedic supervisor. When notified, the supervisor transported the blood to the sites of anticipated need. Total blood use and wastage were recorded. RESULTS: Following two public hearings, we obtained state-wide approval for the initiation of emergency uncrossmatched blood transfusion by paramedics. Over a 1-year period beginning August 27, 2019, 160 units of whole blood were made available for use, and 51 units were transfused to 39 patients, 30 of whom were trauma patients. Other recipients include patients in shock from massive gastrointestinal, peripartum, or other suspected bleeding. Unused units were returned to the providing transfusion service after 1 week and used for hospital patient care without loss. The estimated cost of providing blood per mission was $0.28 and per patient transfused was $1138. CONCLUSIONS: With appropriate attention to detail, it is possible to provide whole blood to an urban paramedical ambulance system with efficient blood component usage, minimal blood wastage, and low cost.

Characteristics and Experiences of Women Physicians and Professionals in NAEMSP.

Introduction: One of the six guiding principles of the EMS Agenda 2050 is to foster a socially equitable care delivery system. A specific recommendation within this principle is that "local EMS leadership, educators and clinicians [should] reflect the diversity of their communities." Research has shown that women comprise a minority of emergency medicine services (EMS) field clinicians. In academic settings, women are represented at lower rates among experienced EMS faculty than within Emergency Medicine clinicians or faculty at large. The reasons for these differences are also unknown. Little data exist describing the number or experience of female physicians and professionals in EMS.Purpose: Our objective was to describe the composition and experiences of EMS physicians, researchers and professionals who participate in the Women in EMS group of the National Association of EMS Physicians (NAEMSP).Methods: We performed a cross-sectional, mixed-methods descriptive study of women belonging to the Women in EMS Committee of NAEMSP. A survey was sent to the 143 members of this group using a list-serve, and the data was collected in Redcap.Results: Seventy-four people completed the survey. Respondents were 96% female, 82% Caucasian, 11% underrepresented minorities (URM), and 7% LGBTQI. Of the 88% that are physicians, 78% are board certified in Emergency Medicine, compared to 55% in EMS. Forty-eight percent reported they received some form of mentorship. Among these respondents, a minority reported female mentorship, which was usually from a remote rather than local mentor (41% vs. 15%). Eighty-three percent of respondents had experienced some form of discrimination or harassment in their career, but only 68% reported their workplace culture discourages such behavior. Thirty-three percent of respondents report receiving unequal recognition because of gender. Thematic evaluation of the qualitative responses showed that respondents felt there were fewer barriers to mentorship and professional advancement opportunities in local work versus national engagement.Conclusions: In a survey evaluating representation of female professionals in EMS, participants reported on their career representations, and experiences of gender-based inequity within their EMS career settings. Several opportunities exist to improve diversity, equity, and inclusion for women in EMS based on our findings.

Novel Technologies and Techniques for Prehospital Airway Management: An NAEMSP Position Statement and Resource Document.

Novel technologies and techniques can influence airway management execution as well as procedural and clinical outcomes. While conventional wisdom underscores the need for rigorous scientific data as a foundation before implementation, high-quality supporting evidence is frequently not available for the prehospital setting. Therefore, implementation decisions are often based upon preliminary or evolving data, or pragmatic information from clinical use. When considering novel technologies and techniques. NAEMSP recommends:Prior to implementing a novel technology or technique, a thorough assessment using the best available scientific data should be conducted on the technical details of the novel approach, as well as the potential effects on operations and outcomes.The decision and degree of effort to adopt, implement, and monitor a novel technology or technique in the prehospital setting will vary by the quality of the best available scientific and clinical information:• Routine use - Technologies and techniques with ample observational but limited or no interventional clinical trial data, or with strong supporting in-hospital data. These techniques may be reasonably adopted in the prehospital setting. This includes video laryngoscopy and bougie-assisted intubation. • Limited use - Technologies and techniques with ample pragmatic clinical use information but limited supporting scientific data. These techniques may be considered in the prehospital setting. This includes suction-assisted laryngoscopy and airway decontamination and cognitive aids. • Rare use - Technologies and techniques with minimal clinical use information. Use of these techniques should be limited in the prehospital setting until evidence exists from more stable clinical environments. This includes intubation boxes.The use of novel technologies and techniques must be accompanied by systematic collection and assessment of data for the purposes of quality improvement, including linkages to patient clinical outcomes.EMS leaders should clearly identify the pathways needed to generate high-quality supporting scientific evidence for novel technologies and techniques.

Risk for Acquiring Coronavirus Disease Illness among Emergency Medical Service Personnel Exposed to Aerosol-Generating Procedures.

We investigated the risk of coronavirus disease (COVID-19)- patients transmitting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to emergency medical service (EMS) providers, stratified by aerosol-generating procedures (AGP), in King County, Washington, USA, during February 16-July 31, 2020. We conducted a retrospective cohort investigation using a statewide COVID-19 registry and identified 1,115 encounters, 182 with ≥1 AGP. Overall, COVID-19 incidence among EMS personnel was 0.57 infections/10,000 person-days. Incidence per 10,000 person-days did not differ whether or not infection was attributed to a COVID-19 patient encounter (0.28 vs. 0.59; p>0.05). The 1 case attributed to a COVID-19 patient encounter occurred within an at-risk period and involved an AGP. We observed a very low risk for COVID-19 infection attributable to patient encounters among EMS first responders, supporting clinical strategies that maintain established practices for treating patients in emergency conditions.

Routine Use of a Bougie Improves First-Attempt Intubation Success in the Out-of-Hospital Setting.

STUDY OBJECTIVE: The bougie is typically treated as a rescue device for difficult airways. We evaluate whether first-attempt success rate during paramedic intubation in the out-of-hospital setting changed with routine use of a bougie. METHODS: A prospective, observational, pre-post study design was used to compare first-attempt success rate during out-of-hospital intubation with direct laryngoscopy for patients intubated 18 months before and 18 months after a protocol change that directed the use of the bougie on the first intubation attempt. We included all patients with a paramedic-performed intubation attempt. Logistic regression was used to examine the association between routine bougie use and first-attempt success rate. RESULTS: Paramedics attempted intubation in 823 patients during the control period and 771 during the bougie period. The first-attempt success rate increased from 70% to 77% (difference 7.0% [95% confidence interval 3% to 11%]). Higher first-attempt success rate was observed during the bougie period across Cormack-Lehane grades, with rates of 91%, 60%, 27%, and 6% for Cormack-Lehane grade 1, 2, 3, and 4 views, respectively, during the control period and 96%, 85%, 50%, and 14%, respectively, during the bougie period. Intubation during the bougie period was independently associated with higher first-attempt success rate (adjusted odds ratio 2.82 [95% confidence interval 1.96 to 4.01]). CONCLUSION: Routine out-of-hospital use of the bougie during direct laryngoscopy was associated with increased first-attempt intubation success rate.

Targeted Temperature Management at 33 Versus 36 Degrees: A Retrospective Cohort Study.

OBJECTIVES: To determine the association between targeted temperature management goal temperature of 33°C versus 36°C and neurologic outcome after out-of-hospital cardiac arrest. DESIGN: This was a retrospective, before-and-after, cohort study. SETTING: Urban, academic, level 1 trauma center from 2010 to 2017. PATIENTS: Adults with nontraumatic out-of-hospital cardiac arrest who received targeted temperature management. INTERVENTIONS: Our primary exposure was targeted temperature management goal temperature, which was changed from 33°C to 36°C in April of 2014 at the study hospital. Primary outcome was neurologically intact survival to discharge. Secondary outcomes included hospital mortality and care processes. MEASUREMENTS AND MAIN RESULTS: Of 782 out-of-hospital cardiac arrest patients transported to the study hospital, 453 (58%) received targeted temperature management. Of these, 258 (57%) were treated during the 33°C period (targeted temperature management 33°C) and 195 (43%) were treated during the 36°C period (targeted temperature management 36°C). Patients treated during targeted temperature management 33°C were older (57 vs 52 yr; p < 0.05) and had more arrests of cardiac etiology (45% vs 35%; p < 0.05), but otherwise had similar baseline characteristics, including initial cardiac rhythm. A total of 40% of patients treated during targeted temperature management 33°C survived with favorable neurologic outcome, compared with 30% in the targeted temperature management 36°C group (p < 0.05). After adjustment for demographic and cardiac arrest characteristics, targeted temperature management 33°C was associated with increased odds of neurologically intact survival to discharge (odds ratio, 1.79; 95% CI, 1.09-2.94). Targeted temperature management 33°C was not associated with significantly improved hospital mortality. Targeted temperature management was implemented faster (1.9 vs 3.5 hr from 911 call; p < 0.001) and more frequently in the emergency department during the targeted temperature management 33°C period (87% vs 55%; p < 0.001). CONCLUSIONS: Comatose, adult out-of-hospital cardiac arrest patients treated during the targeted temperature management 33°C period had higher odds of neurologically intact survival to hospital discharge compared with those treated during the targeted temperature management 36°C period. There was no significant difference in hospital mortality.

Occupational exposures and programmatic response to COVID-19 pandemic: an emergency medical services experience.

Rigorous assessment of occupational COVID-19 risk and personal protective equipment (PPE) use is not well-described. We evaluated 9-1-1 emergency medical services (EMS) encounters for patients with COVID-19 to assess occupational exposure, programmatic strategies to reduce exposure and PPE use. We conducted a retrospective cohort investigation of laboratory-confirmed patients with COVID-19 in King County, Washington, USA, who received 9-1-1 EMS responses from 14 February 2020 to 26 March 2020. We reviewed dispatch, EMS and public health surveillance records to evaluate the temporal relationship between exposure and programmatic changes to EMS operations designed to identify high-risk patients, protect the workforce and conserve PPE. There were 274 EMS encounters for 220 unique COVID-19 patients involving 700 unique EMS providers with 988 EMS person-encounters. Use of 'full' PPE including mask (surgical or N95), eye protection, gown and gloves (MEGG) was 67%. There were 151 person-exposures among 129 individuals, who required 981 quarantine days. Of the 700 EMS providers, 3 (0.4%) tested positive within 14 days of encounter, though these positive tests were not attributed to occupational exposure from inadequate PPE. Programmatic changes were associated with a temporal reduction in exposures. When stratified at the study encounters midpoint, 94% (142/151) of exposures occurred during the first 137 EMS encounters compared with 6% (9/151) during the second 137 EMS encounters (p<0.01). By the investigation's final week, EMS deployed MEGG PPE in 34% (3579/10 468) of all EMS person-encounters. Less than 0.5% of EMS providers experienced COVID-19 illness within 14 days of occupational encounter. Programmatic strategies were associated with a reduction in exposures, while achieving a measured use of PPE.

The impact of accountable care organization participation on hospital patient experience.

BACKGROUND: Accountable care organizations (ACOs) are being implemented rapidly across the Unites States. Previous studies indicated an increasing number of hospitals have participated in ACOs. However, little is known about how ACO participation could influence hospitals' performance. PURPOSE: This study aims to examine the impact of Medicare ACO participation on hospitals' patient experience. METHODOLOGY/APPROACH: Difference-in-difference analyses were conducted to compare 10 patient experience measures between hospitals participating in Medicare ACOs and those not participating. RESULTS: In general, hospitals participating in Pioneer ACOs had significantly improved scores on nursing communication and doctor communication. Shared Savings Program (SSP) ACO participation did not show significant improvement of patient experience. Subgroup analyses indicate that, for hospitals in the middle and top tertile groups in terms of baseline experience, Pioneer ACO and SSP ACO participation was associated with better patient experience. For hospitals in the bottom tertile, Pioneer ACO and SSP ACO participation had no association with patient experience. CONCLUSION: ACO participation improved some aspects of patient experience among hospitals with prior good performance. However, hospitals with historically poor performance did not benefit from ACO participation. PRACTICE IMPLICATIONS: Prior care coordination and quality improvement experience position Medicare ACOs for greater success in terms of patient experience. Hospital leaders need to consider the potential negative consequences of ACO participation and the hospital's preparedness for care coordination.

Pediatric Out-of-Hospital Cardiac Arrest: The Role of the Telecommunicator in Recognition of Cardiac Arrest and Delivery of Bystander Cardiopulmonary Resuscitation.

BACKGROUND: Telecommunicator CPR (T-CPR), whereby emergency dispatch facilitates cardiac arrest recognition and coaches CPR over the telephone, is an important strategy to increase early recognition and bystander CPR in adult out-of-hospital cardiac arrest (OHCA). Little is known about this treatment strategy in the pediatric population. We investigated the role of T-CPR and related performance among pediatric OHCA. METHODS AND RESULTS: This study was a retrospective cohort investigation of OHCA among individuals <18 years in King County, Washington, from April 1, 2013, to December 31, 2019. We reviewed the 911 audio recordings to determine if and how bystander CPR was delivered (unassisted or T-CPR), key time intervals in recognition of arrest, and key components of T-CPR delivery. Of the 185 eligible pediatric OHCAs, 23% (n=43) had bystander CPR initiated unassisted, 59% (n=109) required T-CPR, and 18% (n=33) did not receive CPR before emergency medical services arrival. Among all cases, cardiac arrest was recognized by the telecommunicator in 89% (n=165). Among those receiving T-CPR, the median (interquartile range) interval from start of call to OHCA recognition was 59 seconds (38-87) and first CPR intervention was 115 seconds (94-162). When stratified by age (≤8 versus >8), the older age group was less likely to receive CPR before emergency medical services arrival (88% versus 69%, P=0.002). For those receiving T-CPR, bystanders spent a median of 207 seconds (133-270) performing CPR. The median compression rate was 93 per minute (82-107) among those receiving T-CPR. CONCLUSIONS: T-CPR is an important strategy to increase early recognition and early CPR among pediatric OHCA.

Inflammation, endothelial injury, and the acute respiratory distress syndrome after out-of-hospital cardiac arrest.

Background: Acute respiratory distress syndrome (ARDS) is often seen in patients resuscitated from out-of-hospital cardiac arrest (OHCA). We aim to test whether inflammatory or endothelial injury markers are associated with the development of ARDS in patients hospitalized after OHCA. Methods: We conducted a prospective, cohort, pilot study at an urban academic medical center in 2019 that included a convenience sample of adults with non-traumatic OHCA. Blood and pulmonary edema fluid (PEF) were collected within 12 hours of hospital arrival. Samples were assayed for cytokines (interleukin [IL]-1, tumor necrosis factor-α [TNF-α], tumor necrosis factor receptor1 [TNFR1], IL-6), epithelial injury markers (pulmonary surfactant-associated protein D), endothelial injury markers (Angiopoietin-2 [Ang-2] and glycocalyx degradation products), and other proteins (matrix metallopeptidase-9 and myeloperoxidase). Patients were followed for 7 days for development of ARDS, as adjudicated by 3 blinded reviewers, and through hospital discharge for mortality and neurological outcome. We examined associations between biomarker concentrations and ARDS, hospital mortality, and neurological outcome using multivariable logistic regression. Latent phase analysis was used to identify distinct biological classes associated with outcomes. Results: 41 patients were enrolled. Mean age was 58 years, 29% were female, and 22% had a respiratory etiology for cardiac arrest. Seven patients (17%) developed ARDS within 7 days. There were no significant associations between individual biomarkers and development of ARDS in adjusted analyses, nor survival or neurologic status after adjusting for use of targeted temperature management (TTM) and initial cardiac arrest rhythm. Elevated Ang-2 and TNFR-1 were associated with decreased survival (RR = 0.6, 95% CI = 0.3-1.0; RR = 0.5, 95% CI = 0.3-0.9; respectively), and poor neurologic status at discharge (RR = 0.4, 95% CI = 0.2-0.8; RR = 0.4, 95% CI = 0.2-0.9) in unadjusted associations. Conclusion: OHCA patients have markedly elevated plasma and pulmonary edema fluid biomarker concentrations, indicating widespread inflammation, epithelial injury, and endothelial activation. Biomarker concentrations were not associated with ARDS development, though several distinct biological phenotypes warrant further exploration. Latent phase analysis demonstrated that patients with low biomarker levels aside from TNF-α and TNFR-1 (Class 2) fared worse than other patients. Future research may benefit from considering other tools to predict and prevent development of ARDS in this population.

The impact of COVID-19 pandemic on out-of-hospital cardiac arrest: An individual patient data meta-analysis.

AIM: Prior studies have reported increased out-of-hospital cardiac arrests (OHCA) incidence and lower survival during the COVID-19 pandemic. We evaluated how the COVID-19 pandemic affected OHCA incidence, bystander CPR rate and patients' outcomes, accounting for regional COVID-19 incidence and OHCA characteristics. METHODS: Individual patient data meta-analysis of studies which provided a comparison of OHCA incidence during the first pandemic wave (COVID-period) with a reference period of the previous year(s) (pre-COVID period). We computed COVID-19 incidence per 100,000 inhabitants in each of 97 regions per each week and divided it into its quartiles. RESULTS: We considered a total of 49,882 patients in 10 studies. OHCA incidence increased significantly compared to previous years in regions where weekly COVID-19 incidence was in the fourth quartile (>136/100,000/week), and patients in these regions had a lower odds of bystander CPR (OR 0.49, 95%CI 0.29-0.81, p = 0.005). Overall, the COVID-period was associated with an increase in medical etiology (89.2% vs 87.5%, p < 0.001) and OHCAs at home (74.7% vs 67.4%, p < 0.001), and a decrease in shockable initial rhythm (16.5% vs 20.3%, p < 0.001). The COVID-period was independently associated with pre-hospital death (OR 1.73, 95%CI 1.55-1.93, p < 0.001) and negatively associated with survival to hospital admission (OR 0.68, 95%CI 0.64-0.72, p < 0.001) and survival to discharge (OR 0.50, 95%CI 0.46-0.54, p < 0.001). CONCLUSIONS: During the first COVID-19 pandemic wave, there was higher OHCA incidence and lower bystander CPR rate in regions with a high-burden of COVID-19. COVID-19 was also associated with a change in patient characteristics and lower survival independently of COVID-19 incidence in the region where OHCA occurred.

Metronome use improves achievement of a target compression rate in out-of-hospital cardiac arrest: A retrospective analysis.

Aim: The aim of this study was to evaluate chest compression rates (CCR) with and without the use of a metronome during treatment of out-of-hospital cardiac arrest (OHCA). Methods: We performed a retrospective cohort investigation of non-traumatic OHCA cases treated by Seattle Fire Department from January 1, 2013, to December 31, 2019. The exposure was a metronome running during CPR at a rate of 110 beats per minute. The primary outcome was the median CCR for all periods of CPR with a metronome compared to periods without a metronome. Results: We included 2,132 OHCA cases with 32,776 minutes of CPR data; 15,667 (48%) minutes had no metronome use, and 17,109 (52%) minutes had a metronome used. Without a metronome, the median CCR was 112.8 per minute with an interquartile range of 108.4 - 119.1, and 27% of minutes were above 120 or less than 100. With a metronome, the median CCR was 110.5 per minute with an interquartile range of 110.0-112.0, and less than 4% of minutes were above 120 or less than 100. The compression rate was 109, 110, or 111 in 62% of minutes with a metronome compared to 18% of minutes with no metronome. Conclusion: The use of a metronome during CPR resulted in increased compliance to a predetermined compression rate. Metronomes are a simple tool that improves achievement of a target compression rate with little variance from that target.

THE COMPENSATORY RESERVE INDEX FOR PREDICTING HEMORRHAGIC SHOCK IN PREHOSPITAL TRAUMA.

ABSTRACT: Background: The compensatory reserve index (CRI) is a noninvasive, continuous measure designed to detect intravascular volume loss. CRI is derived from the pulse oximetry waveform and reflects the proportion of physiologic reserve remaining before clinical hemodynamic decompensation. Methods: In this prospective, observational, prehospital cohort study, we measured CRI in injured patients transported by emergency medical services (EMS) to a single Level I trauma center. We determined whether the rolling average of CRI values over 60 s (CRI trend [CRI-T]) predicts in-hospital diagnosis of hemorrhagic shock, defined as blood product administration in the prehospital setting or within 4 h of hospital arrival. We hypothesized that lower CRI-T values would be associated with an increased likelihood of hemorrhagic shock and better predict hemorrhagic shock than prehospital vital signs. Results: Prehospital CRI was collected on 696 adult trauma patients, 21% of whom met our definition of hemorrhagic shock. The minimum CRI-T was 0.14 (interquartile range [IQR], 0.08-0.31) in those with hemorrhagic shock and 0.31 (IQR 0.15-0.50) in those without ( P = <0.0001). The positive likelihood ratio of a CRI-T value <0.2 predicting hemorrhagic shock was 1.85 (95% confidence interval [CI], 1.55-2.22). The area under the ROC curve (AUC) for the minimum CRI-T predicting hemorrhagic shock was 0.65 (95% CI, 0.60-0.70), which outperformed initial prehospital HR (0.56; 95% CI, 0.50-0.62) but underperformed EMS systolic blood pressure and shock index (0.74; 95% CI, 0.70-0.79 and 0.72; 95% CI, 0.67-0.77, respectively). Conclusions: Low prehospital CRI-T predicts blood product transfusion by EMS or within 4 hours of hospital arrival but is less prognostic than EMS blood pressure or shock index. The evaluated version of CRI may be useful in an austere setting at identifying injured patients that require the most significant medical resources. CRI may be improved with noise filtering to attenuate the effects of vibration and patient movement.

Diagnostic yield, safety, and outcomes of Head-to-pelvis sudden death CT imaging in post arrest care: The CT FIRST cohort study.

AIM: Our aim was to test whether a head-to-pelvis CT scan improves diagnostic yield and speed to identify causes for out of hospital circulatory arrest (OHCA). METHODS: CT FIRST was a prospective observational pre-/post-cohort study of patients successfully resuscitated from OHCA. Inclusion criteria included unknown cause for arrest, age >18 years, stability to undergo CT, and no known cardiomyopathy or obstructive coronary artery disease. A head-to-pelvis sudden death CT (SDCT) scan within 6 hours of hospital arrival was added to the standard of care for patients resuscitated from OHCA (post-cohort) and compared to standard of care (SOC) alone (pre-cohort). The primary outcome was SDCT diagnostic yield. Secondary outcomes included time to identifying OHCA cause and time-critical diagnoses, SDCT safety, and survival to hospital discharge. RESULTS: Baseline characteristics between the SDCT (N = 104) and the SOC (N = 143) cohorts were similar. CT scans (either head, chest, and/or abdomen) were ordered in 74 (52%) of SOC patients. Adding SDCT scanning identified 92% of causes for arrest compared to 75% (SOC-cohort; p value < 0.001) and reduced the time to diagnosis by 78% (SDCT 3.1 hours, SOC alone 14.1 hours, p < 0.0001). Identification of critical diagnoses was similar between cohorts, but SDCT reduced delayed (>6 hours) identification of critical diagnoses by 81% (p < 0.001). SDCT safety endpoints were similar including acute kidney injury. Patient survival to discharge was similar between cohorts. DISCUSSION: SDCT scanning early after OHCA resuscitation safely improved the efficiency and diagnostic yield for causes of arrest compared to the standard of care alone. CLINICAL TRIALS NUMBER: NCT03111043.

Acute SARS-CoV-2 Infection and Incidence and Outcomes of Out-of-Hospital Cardiac Arrest.

Importance: Little is known about how COVID-19 affects the incidence or outcomes of out-of-hospital cardiac arrest (OHCA), and it is possible that more generalized factors beyond SARS-CoV-2 infection are primarily responsible for changes in OHCA incidence and outcome. Objective: To assess whether COVID-19 is associated with OHCA incidence and outcomes. Design, Setting, and Participants: This retrospective cohort study was conducted in Seattle and King County, Washington. Participants included persons aged 18 years or older with nontraumatic OHCA attended by emergency medical services (EMS) between January 1, 2018, and December 31, 2021. Data analysis was performed from November 2022 to March 2023. Exposures: Prepandemic (2018-2019) and pandemic (2020-2021) periods and SARS-CoV-2 infection. Main Outcomes and Measures: The primary outcomes were OHCA incidence and patient outcomes (ie, survival to hospital discharge). Mediation analysis was used to determine the percentage change in OHCA incidence and outcomes between prepandemic and pandemic periods that was attributable to acute SARS-CoV-2 infection vs conventional Utstein elements related to OHCA circumstances (ie, witness status and OHCA location) and resuscitation care (ie, bystander cardiopulmonary resuscitation, early defibrillation, and EMS response intervals). Results: There were a total of 13 081 patients with OHCA (7102 dead upon EMS arrival and 5979 EMS treated). Among EMS-treated patients, the median (IQR) age was 64.0 (51.0-75.0) years, 3864 (64.6%) were male, and 1027 (17.2%) survived to hospital discharge. The total number of patients with OHCA increased by 19.0% (from 5963 in the prepandemic period to 7118 in the pandemic period), corresponding to an incidence increase from 168.8 to 195.3 events per 100 000 person-years. Of EMS-treated patients with OHCA during the pandemic period, 194 (6.2%) were acutely infected with SARS-CoV-2 compared with 7 of 191 EMS-attended but untreated patients with OHCA (3.7%). In time-series correlation analysis, there was a positive correlation between community SARS-CoV-2 incidence and overall OHCA incidence (r = 0.27; P = .01), as well as OHCA incidence with acute SARS-CoV-2 infection (r = 0.43; P < .001). The survival rate during the pandemic period was lower than that in the prepandemic period (483 patients [15.4%] vs 544 patients [19.2%]). During the pandemic, those with OHCA and acute SARS-CoV-2 infection had lower likelihood of survival compared with those without acute infection (12 patients [6.2%] vs 471 patients [16.0%]). SARS-CoV-2 infection itself accounted for 18.5% of the pandemic survival decline, whereas Utstein elements mediated 68.2% of the survival decline. Conclusions and Relevance: In this cohort study of COVID-19 and OHCA, a substantial proportion of the higher OHCA incidence and lower survival during the pandemic was not directly due to SARS-CoV-2 infection but indirect factors that challenged OHCA prevention and treatment.