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.

A pilot evaluation of respiratory mechanics during prehospital manual ventilation.

INTRODUCTION: Respiratory mechanics, such as tidal volume (VT) and inspiratory pressures, may affect outcome in hospitalized patients with respiratory failure. Little is known about respiratory mechanics in the prehospital setting. METHODS: In this prospective, pilot investigation of patients receiving prehospital advanced airway placement, paramedics applied a device to measure respiratory mechanics. We evaluated tidal volume (VT) per predicted body weight (VTPBW) to determine the proportion of breaths within the lung-protective range of 4-10 mL/kg per PBW overall, according to ventilation bag volume (large versus small) and cardiac arrest status (active CPR, post-ROSC, non-arrest). RESULTS: Over 16-months, 7371 post-intubation breaths were measured in 54 patients, 32 patients with cardiac arrest and 22 with other conditions. Paramedics ventilated 19 patients with a small bag and 35 patients with a large bag. Overall, mean VT was 435 mL (95% CI 403, 467); VTPBW was 7.0 mL/kg (95% CI 6.4, 7.6) with 75% within the lung-protective range. Mean VTPBW and peak pressure differed according to arrest status (absolute difference -0.36 mL/kg and 32 cmH2O for active CPR compared to post-ROSC), though not according to bag size. CONCLUSIONS: We observed that measuring respiratory mechanics in the prehospital setting was feasible. Tidal volumes were generally delivered within a safe range. Respiratory mechanics varied most significantly with active CPR with lower VTPBW and higher peak pressures, though did not seem to be affected by bag size. Future work might examine the relationship between respiratory mechanics and outcomes, which may identify opportunities to improve clinical outcomes.

Association between functional status at hospital discharge and long-term survival after out-of-hospital-cardiac-arrest.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) causes brain injury. Functional status of survivors at hospital discharge is a core resuscitation measure, frequently using the Cerebral Performance Category (CPC) or modified Rankin Scale (mRS). Which scale better predicts long-term survival following OHCA is not known. METHODS: We evaluated long-term survival after hospital discharge in a retrospective cohort of persons resuscitated from OHCA in King County, WA from 2007 to 2015. Patients were independently assessed at discharge using both scales, leveraging the regional quality improvement registry, which records the 5-level CPC, and concurrent research studies involving the Resuscitation Outcomes Consortium, which used the 7-level mRS, taken from information in the hospital record. The risk of mortality associated with CPC and mRS categories was estimated using Kaplan-Meier survival analysis and Cox proportional hazards regression. RESULTS: Among 878 eligible patients discharged alive, there were 358 deaths during 9118.5 person-years of follow-up. Overall 1, 5 and 10-year survival was 84.4%, 68.5%, and 53.7% and varied according to CPC and mRS (p < 0.01 per Kaplan-Meier). Compared to CPC-1, hazard ratio (HR) increased incrementally for CPC-2 = 1.33 (1.03-1.73), CPC-3 = 1.90 (1.37-2.65), and CPC-4 = 8.25 (5.63-12.10). Compared to mRS = 0, HR for mRS-1 = 1.02 (0.66-1.58), mRS-2 = 1.52 (1.00-2.32), mRS-3 = 1.41 (0.92-2.14), mRS-4 = 2.00 (1.37-2.97), and mRS-5 = 4.90 (3.23-7.44). CONCLUSION: In OHCA survivors, CPC and mRS scales both predicted long-term survival. However mRS 0-1 and 2-3 groups did not have distinct prognoses, suggesting that a consolidated mRS score may simplify capture of relevant prognostic information for survival predictions.

Prehospital tourniquet use: An evaluation of community application and outcome.

BACKGROUND: There is substantial investment in layperson and first responder training involving tourniquet use for hemorrhage control. Little is known however about prehospital tourniquet application, field conversion, or outcomes in the civilian setting. We describe the experience of a metropolitan region with prehospital tourniquet application. METHODS: We conducted a retrospective cohort study characterizing prehospital tourniquet use treated by emergency medical services (EMS) in King County, Washington, from January 2018 to June 2019. Emergency medical services and hospital records were abstracted for demographics, injury mechanism, tourniquet details, clinical care, and outcomes. We evaluated the incidence of tourniquet application, who applied the device (EMS, law enforcement, or layperson), and subsequent course. RESULTS: A total of 168 patients received tourniquet application, an incidence of 5.1 per 100,000 person-years and 3.48 per 1,000 EMS responses for trauma. Tourniquets were applied for penetrating trauma (64%), blunt trauma (30%), and bleeding ateriovenous fistulas (7%). A subset was critically ill: 13% had systolic blood pressures of <90 mm Hg, 8% had Glasgow Coma Scale score of <13, and 3% had cardiac arrest. Among initial applications, 48% were placed by law enforcement, 33% by laypersons, and 18% by EMS. Among tourniquets applied by layperson or law enforcement (n = 137), EMS relied solely on the original tourniquet in 45% (n = 61), placed a second tourniquet in 20% (n = 28), and removed the tourniquet without replacement in 35% (n = 48). Overall, 24% required massive transfusion, 59% underwent urgent surgery, and 21% required vascular surgery. Mortality was 3% (n = 4). At hospital discharge, the tourniquet limb was fully functional in 81%, partially functional in 10%, and nonfunctional in 9%; decreased function was not attributed to tourniquet application. CONCLUSION: The high rate of application, need for urgent hospital intervention in a subset, and low incidence of apparent complication suggest that efforts to increase access and early tourniquet use can provide public health benefit. LEVEL OF EVIDENCE: Therapeutic, level IV.

Bystander Cardiopulmonary Resuscitation Quality: Potential for Improvements in Cardiac Arrest Resuscitation.

Background Bystander cardiopulmonary resuscitation (CPR) is a critical intervention to improve survival following out-of-hospital cardiac arrest. We evaluated the quality of bystander CPR and whether performance varied according to the number of bystanders or provision of telecommunicator CPR (TCPR). Methods and Results We investigated non-traumatic out-of-hospital cardiac arrest occurring in a large metropolitan emergency medical system during a 6-month period. Information about bystander care was ascertained through review of the 9-1-1 recordings in addition to emergency medical system and hospital records to determine bystander CPR status (none versus TCPR versus unassisted), the number of bystanders on-scene, and CPR performance metrics of compression fraction and compression rate. Of the 428 eligible out-of-hospital cardiac arrest, 76.4% received bystander CPR including 43.7% unassisted CPR and 56.3% TCPR; 35.2% had one bystander, 33.3% had 2 bystanders, and 31.5% had ≥3 bystanders. Overall compression fraction was 59% with a compression rate of 88 per minute. CPR differed according to TCPR status (fraction=52%, rate=87 per minute for TCPR versus fraction=69%, rate=102 for unassisted CPR, P<0.05 for each comparison) and the number of bystanders (fraction=55%, rate=87 per minute for 1 bystander, fraction=59%, rate=89 for 2 bystanders, fraction=65%, rate=97 for ≥3 bystanders, test for trend P<0.05 for each metric). Additional bystander actions were uncommon to include rotation of compressors (3.1%) or application of an automated external defibrillator (8.0%). Conclusions Bystander CPR quality as gauged by compression fraction and rate approached guideline goals though performance depended upon the type of CPR and number of bystanders.

Clinical Characteristics of Patients With Coronavirus Disease 2019 (COVID-19) Receiving Emergency Medical Services in King County, Washington.

Importance: The ability to identify patients with coronavirus disease 2019 (COVID-19) in the prehospital emergency setting could inform strategies for infection control and use of personal protective equipment. However, little is known about the presentation of patients with COVID-19 requiring emergency care, particularly those who used 911 emergency medical services (EMS). Objective: To describe patient characteristics and prehospital presentation of patients with COVID-19 cared for by EMS. Design, Setting, and Participants: This retrospective cohort study included 124 patients who required 911 EMS care for COVID-19 in King County, Washington, a large metropolitan region covering 2300 square miles with 2.2 million residents in urban, suburban, and rural areas, between February 1, 2020, and March 18, 2020. Exposures: COVID-19 was diagnosed by reverse transcription-polymerase chain reaction detection of severe acute respiratory syndrome coronavirus 2 from nasopharyngeal swabs. Test results were available a median (interquartile range) of 5 (3-9) days after the EMS encounter. Main Outcomes and Measures: Prevalence of clinical characteristics, symptoms, examination signs, and EMS impression and care. Results: Of the 775 confirmed COVID-19 cases in King County, EMS responded to 124 (16.0%), with a total of 147 unique 911 encounters. The mean (SD) age was 75.7 (13.2) years, 66 patients (53.2%) were women, 47 patients (37.9%) had 3 or more chronic health conditions, and 57 patients (46.0%) resided in a long-term care facility. Based on EMS evaluation, 43 of 147 encounters (29.3%) had no symptoms of fever, cough, or shortness of breath. Based on individual examination findings, fever, tachypnea, or hypoxia were only present in a limited portion of cases, as follows: 43 of 84 encounters (51.2%), 42 of 131 (32.1%), and 60 of 112 (53.6%), respectively. Advanced care was typically not required, although in 24 encounters (16.3%), patients received care associated with aerosol-generating procedures. As of June 1, 2020, mortality among the study cohort was 52.4% (65 patients). Conclusions and Relevance: The findings of this cohort study suggest that screening based on conventional COVID-19 symptoms or corresponding examination findings of febrile respiratory illness may not possess the necessary sensitivity for early diagnostic suspicion, at least in the prehospital emergency setting. The findings have potential implications for early identification of COVID-19 and effective strategies to mitigate infectious risk during emergency care.