Comparison of lung ultrasound scoring systems for the prognosis of COVID-19 in the emergency department: An international prospective cohort study.

Purpose: The purpose of this study was to evaluate whether the lung ultrasound (LUS) scores applied to an international cohort of patients presenting to the emergency department (ED) with suspected COVID-19, and subsequently admitted with proven disease, could prognosticate clinical outcomes. Methods: This was an international, multicentre, prospective, observational cohort study of patients who received LUS and were followed for the composite primary outcome of intubation, intensive care unit (ICU) admission or death. LUS scores were later applied including two 12-zone protocols ('de Alencar score' and 'CLUE score'), a 12-zone protocol with lung and pleural findings ('Ji score') and an 11-zone protocol ('Tung-Chen score'). The primary analysis comprised logistic regression modelling of the composite primary outcome, with the LUS scores analysed individually as predictor variables. Results: Between April 2020 to April 2022, 129 patients with COVID-19 had LUS performed according to the protocol and 24 (18.6%) met the composite primary endpoint. No association was seen between the LUS score and the composite primary end point for the de Alencar score [odds ratio (OR) = 1.04; 95% confidence interval (CI): 0.97-1.11; P = 0.29], the CLUE score (OR = 1.03; 95% CI: 0.96-1.10; P = 0.40), the Ji score (OR = 1.02; 95% CI: 0.97-1.07; P = 0.40) or the Tung-Chen score (OR = 1.02; 95% CI: 0.97-1.08). Discussion: Compared to these earlier studies performed at the start of the pandemic, the negative outcome of our study could reflect the changing scenario of the COVID-19 pandemic, including patient, disease, and system factors. The analysis suggests that the study may have been underpowered to detect a weaker association between a LUS score and the primary outcome. Conclusion: In an international cohort of adult patients presenting to the ED with suspected COVID-19 disease who had LUS performed and were subsequently admitted to hospital, LUS severity scores did not prognosticate the need for invasive ventilation, ICU admission or death.

Review article: Accuracy of emergency physician performed point-of-care ultrasound of the thoracic aorta: A systematic review and narrative synthesis of the literature.

Point-of-care ultrasound (POCUS) is becoming ubiquitous in emergency medicine. POCUS for abdominal aortic aneurysm is well established in practice. The thoracic aorta can also be assessed by POCUS for dissection and aneurysm and transthoracic echocardiography is endorsed by international guidelines as an initial test for thoracic aortic pathologies. A systematic search of Ovid Medline, PubMed, EMBASE, SCOPUS and Web of Science from January 2000 to August 2022 identified four studies evaluating diagnostic accuracy of emergency physician POCUS for thoracic aortic dissection (TAD) and five studies for thoracic aortic aneurysm (TAA). Study designs were heterogeneous including differing diagnostic criteria for aortic pathology. Convenience recruitment was frequent in prospective studies. Sensitivity and specificity ranges for studies of TAD were 41-91% and 94-100%, respectively when an intimal flap was seen. Sensitivity and specificity ranges for studies of thoracic aorta dilation >40 mm were 50-100% and 93-100%, respectively; for >45 mm ranges were 64-65% and 95-99%. Literature review identified that POCUS is specific for TAD and TAA. POCUS reduces the time to diagnosis of thoracic aortic pathology; however, it remains insensitive and cannot be recommended as a stand-alone rule-out test. We suggest that detection of thoracic aorta dilation >40 mm by POCUS at any site increases the suspicion of serious aortic pathology. Studies incorporating algorithmic use of POCUS, Aortic Dissection Detection Risk Score and D-dimer as decision tools are promising and may improve current ED practices. Further research is warranted in this rapidly evolving field.

Management of patients presenting with low back pain to a private hospital emergency department in Melbourne, Australia.

OBJECTIVE: Recent studies suggest many patients with non-specific low back pain presenting to public hospital EDs receive low-value care. The primary aim was to describe management of patients presenting with low back pain to the ED of a private hospital in Melbourne, Australia, and received a final ED diagnosis of non-specific low back pain. We also determined predictors of hospital admission. METHODS: Retrospective review of patients who presented with low back pain and received a final ED diagnosis of non-specific low back pain to Cabrini Malvern ED in 2015. Demographics, lumbar spinal imaging, pathology tests and medications were extracted from hospital records. Multivariate logistic regression was used to determine independent predictors of hospital admission. RESULTS: Four hundred and fifty presentations were included (60% female); 238 (52.9%) were admitted to hospital. One hundred and seventy-seven (39.3%) patients received lumbar spine imaging. Two hundred and eighty (62.2%) patients had pathology tests and 391 (86.9%) received medications, which included opioids (n = 298, 66.2%), paracetamol (n = 219, 48.7%), NSAIDs (n = 161, 35.8%), benzodiazepines (n = 118, 26.2%) and pregabalin (n = 26, 5.8%). Predictors of hospital admission included older age (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.02-1.05), arrival by ambulance (OR 2.03, 95% CI 1.06-3.90) and receipt of pathology tests (OR 3.32, 95% CI 2.01-5.49) or computed tomography scans (OR 1.86, 95% CI 1.12-3.11). CONCLUSION: We observed high rates of imaging, pathology tests and hospital admissions compared with previous public hospital studies, while medication use was similar. Implementation of strategies to optimise evidence-based ED care is needed to reduce low-value care and improve patient outcomes.

Emergency medicine patient wait time multivariable prediction models: a multicentre derivation and validation study.

OBJECTIVE: Patients, families and community members would like emergency department wait time visibility. This would improve patient journeys through emergency medicine. The study objective was to derive, internally and externally validate machine learning models to predict emergency patient wait times that are applicable to a wide variety of emergency departments. METHODS: Twelve emergency departments provided 3 years of retrospective administrative data from Australia (2017-2019). Descriptive and exploratory analyses were undertaken on the datasets. Statistical and machine learning models were developed to predict wait times at each site and were internally and externally validated. Model performance was tested on COVID-19 period data (January to June 2020). RESULTS: There were 1 930 609 patient episodes analysed and median site wait times varied from 24 to 54 min. Individual site model prediction median absolute errors varied from±22.6 min (95% CI 22.4 to 22.9) to ±44.0 min (95% CI 43.4 to 44.4). Global model prediction median absolute errors varied from ±33.9 min (95% CI 33.4 to 34.0) to ±43.8 min (95% CI 43.7 to 43.9). Random forest and linear regression models performed the best, rolling average models underestimated wait times. Important variables were triage category, last-k patient average wait time and arrival time. Wait time prediction models are not transferable across hospitals. Models performed well during the COVID-19 lockdown period. CONCLUSIONS: Electronic emergency demographic and flow information can be used to approximate emergency patient wait times. A general model is less accurate if applied without site-specific factors.

Predicting Ambulance Patient Wait Times: A Multicenter Derivation and Validation Study.

STUDY OBJECTIVE: To derive and internally and externally validate machine-learning models to predict emergency ambulance patient door-to-off-stretcher wait times that are applicable to a wide variety of emergency departments. METHODS: Nine emergency departments provided 3 years (2017 to 2019) of retrospective administrative data from Australia. Descriptive and exploratory analyses were undertaken on the datasets. Statistical and machine-learning models were developed to predict wait times at each site and were internally and externally validated. RESULTS: There were 421,894 episodes analyzed, and median site off-load times varied from 13 (interquartile range [IQR], 9 to 20) to 29 (IQR, 16 to 48) minutes. The global site prediction model median absolute errors were 11.7 minutes (95% confidence interval [CI], 11.7 to 11.8) using linear regression and 12.8 minutes (95% CI, 12.7 to 12.9) using elastic net. The individual site model prediction median absolute errors varied from the most accurate at 6.3 minutes (95% CI, 6.2 to 6.4) to the least accurate at 16.1 minutes (95% CI, 15.8 to 16.3). The model technique performance was the same for linear regression, random forests, elastic net, and rolling average. The important variables were the last k-patient average waits, triage category, and patient age. The global model performed at the lower end of the accuracy range compared with models for the individual sites but was within tolerable limits. CONCLUSION: Electronic emergency demographic and flow information can be used to estimate emergency ambulance patient off-stretcher times. Models can be built with reasonable accuracy for multiple hospitals using a small number of point-of-care variables.

Prone Positioning of Nonintubated Patients With Coronavirus Disease 2019-A Systematic Review and Meta-Analysis.

OBJECTIVES: Several studies have reported prone positioning of nonintubated patients with coronavirus diseases 2019-related hypoxemic respiratory failure. This systematic review and meta-analysis evaluated the impact of prone positioning on oxygenation and clinical outcomes. DESIGN AND SETTING: We searched PubMed, Embase, and the coronavirus diseases 2019 living systematic review from December 1, 2019, to November 9, 2020. SUBJECTS AND INTERVENTION: Studies reporting prone positioning in hypoxemic, nonintubated adult patients with coronavirus diseases 2019 were included. MEASUREMENTS AND MAIN RESULTS: Data on prone positioning location (ICU vs non-ICU), prone positioning dose (total minutes/d), frequency (sessions/d), respiratory supports during prone positioning, relative changes in oxygenation variables (peripheral oxygen saturation, Pao2, and ratio of Pao2 to the Fio2), respiratory rate pre and post prone positioning, intubation rate, and mortality were extracted. Twenty-five observational studies reporting prone positioning in 758 patients were included. There was substantial heterogeneity in prone positioning location, dose and frequency, and respiratory supports provided. Significant improvements were seen in ratio of Pao2 to the Fio2 (mean difference, 39; 95% CI, 25-54), Pao2 (mean difference, 20 mm Hg; 95% CI, 14-25), and peripheral oxygen saturation (mean difference, 4.74%; 95% CI, 3-6%). Respiratory rate decreased post prone positioning (mean difference, -3.2 breaths/min; 95% CI, -4.6 to -1.9). Intubation and mortality rates were 24% (95% CI, 17-32%) and 13% (95% CI, 6-19%), respectively. There was no difference in intubation rate in those receiving prone positioning within and outside ICU (32% [69/214] vs 33% [107/320]; p = 0.84). No major adverse events were recorded in small subset of studies that reported them. CONCLUSIONS: Despite the significant variability in frequency and duration of prone positioning and respiratory supports applied, prone positioning was associated with improvement in oxygenation variables without any reported serious adverse events. The results are limited by a lack of controls and adjustments for confounders. Whether this improvement in oxygenation results in meaningful patient-centered outcomes such as reduced intubation or mortality rates requires testing in well-designed randomized clinical trials.

Case Fatality Rates for Patients with COVID-19 Requiring Invasive Mechanical Ventilation. A Meta-analysis.

Rationale: Initial reports of case fatality rates (CFRs) among adults with coronavirus disease (COVID-19) receiving invasive mechanical ventilation (IMV) are highly variable.Objectives: To examine the CFR of patients with COVID-19 receiving IMV.Methods: Two authors independently searched PubMed, Embase, medRxiv, bioRxiv, the COVID-19 living systematic review, and national registry databases. The primary outcome was the "reported CFR" for patients with confirmed COVID-19 requiring IMV. "Definitive hospital CFR" for patients with outcomes at hospital discharge was also investigated. Finally, CFR was analyzed by patient age, geographic region, and study quality on the basis of the Newcastle-Ottawa Scale.Measurements and Results: Sixty-nine studies were included, describing 57,420 adult patients with COVID-19 who received IMV. Overall reported CFR was estimated as 45% (95% confidence interval [CI], 39-52%). Fifty-four of 69 studies stated whether hospital outcomes were available but provided a definitive hospital outcome on only 13,120 (22.8%) of the total IMV patient population. Among studies in which age-stratified CFR was available, pooled CFR estimates ranged from 47.9% (95% CI, 46.4-49.4%) in younger patients (age ≤40 yr) to 84.4% (95% CI, 83.3-85.4%) in older patients (age >80 yr). CFR was also higher in early COVID-19 epicenters. Overall heterogeneity is high (I2 >90%), with nonsignificant Egger's regression test suggesting no publication bias.Conclusions: Almost half of patients with COVID-19 receiving IMV died based on the reported CFR, but variable CFR reporting methods resulted in a wide range of CFRs between studies. The reported CFR was higher in older patients and in early pandemic epicenters, which may be influenced by limited ICU resources. Reporting of definitive outcomes on all patients would facilitate comparisons between studies.Systematic review registered with PROSPERO (CRD42020186997).

Management of adult cardiac arrest in the COVID-19 era: consensus statement from the Australasian College for Emergency Medicine.

INTRODUCTION: The global pandemic of coronavirus disease 2019 (COVID-19) has caused significant worldwide disruption. Although Australia and New Zealand have not been affected as much as some other countries, resuscitation may still pose a risk to health care workers and necessitates a change to our traditional approach. This consensus statement for adult cardiac arrest in the setting of COVID-19 has been produced by the Australasian College for Emergency Medicine (ACEM) and aligns with national and international recommendations. MAIN RECOMMENDATIONS: In a setting of low community transmission, most cardiac arrests are not due to COVID-19. Early defibrillation saves lives and is not considered an aerosol generating procedure. Compression-only cardiopulmonary resuscitation is thought to be a low risk procedure and can be safely initiated with the patient's mouth and nose covered. All other resuscitative procedures are considered aerosol generating and require the use of airborne personal protective equipment (PPE). It is important to balance the appropriateness of resuscitation against the risk of infection. Methods to reduce nosocomial transmission of COVID-19 include a physical barrier such as a towel or mask over the patient's mouth and nose, appropriate use of PPE, minimising the staff involved in resuscitation, and use of mechanical chest compression devices when available. If COVID-19 significantly affects hospital resource availability, the ethics of resource allocation must be considered. CHANGES IN MANAGEMENT: The changes outlined in this document require a significant adaptation for many doctors, nurses and paramedics. It is critically important that all health care workers have regular PPE and advanced life support training, are able to access in situ simulation sessions, and receive extensive debriefing after actual resuscitations. This will ensure safe, timely and effective management of the patients with cardiac arrest in the COVID-19 era.

The Australasian Resuscitation In Sepsis Evaluation: Fluids or vasopressors in emergency department sepsis (ARISE FLUIDS), a multi-centre observational study describing current practice in Australia and New Zealand.

OBJECTIVES: To describe haemodynamic resuscitation practices in ED patients with suspected sepsis and hypotension. METHODS: This was a prospective, multicentre, observational study conducted in 70 hospitals in Australia and New Zealand between September 2018 and January 2019. Consecutive adults presenting to the ED during a 30-day period at each site, with suspected sepsis and hypotension (systolic blood pressure <100 mmHg) despite at least 1000 mL fluid resuscitation, were eligible. Data included baseline demographics, clinical and laboratory variables and intravenous fluid volume administered, vasopressor administration at baseline and 6- and 24-h post-enrolment, time to antimicrobial administration, intensive care admission, organ support and in-hospital mortality. RESULTS: A total of 4477 patients were screened and 591 were included with a mean (standard deviation) age of 62 (19) years, Acute Physiology and Chronic Health Evaluation II score 15.2 (6.6) and a median (interquartile range) systolic blood pressure of 94 mmHg (87-100). Median time to first intravenous antimicrobials was 77 min (42-148). A vasopressor infusion was commenced within 24 h in 177 (30.2%) patients, with noradrenaline the most frequently used (n = 138, 78%). A median of 2000 mL (1500-3000) of intravenous fluids was administered prior to commencing vasopressors. The total volume of fluid administered from pre-enrolment to 24 h was 4200 mL (3000-5661), with a range from 1000 to 12 200 mL. Two hundred and eighteen patients (37.1%) were admitted to an intensive care unit. Overall in-hospital mortality was 6.2% (95% confidence interval 4.4-8.5%). CONCLUSION: Current resuscitation practice in patients with sepsis and hypotension varies widely and occupies the spectrum between a restricted volume/earlier vasopressor and liberal fluid/later vasopressor strategy.

Expectations and experiences of women presenting to emergency departments with early pregnancy bleeding.

OBJECTIVE: To explore women's expectations and experiences when presenting to the ED with early pregnancy bleeding. METHODS: We conducted a qualitative study where women presenting to the ED with early pregnancy bleeding participated in two semi-structured interviews. An initial interview explored expectations of care and was conducted prior to ED treatment. A follow-up interview about experiences with care was conducted after discharge from the ED. Women were recruited from three EDs in suburban Melbourne: one tertiary referral centre and two urban district hospitals. RESULTS: Thirty women with early pregnancy bleeding completed the initial interview and 22 completed the follow-up interview. Eleven participants were primigravid women and 21 participants had never experienced early pregnancy bleeding prior to their ED presentation. Four themes relating to the patient experience were identified: (i) Acknowledgement of patients' concerns by hospital staff, including informing patients of progress and explanation of investigation results; (ii) Early pregnancy bleeding as a distressing experience, with most participants expecting that this would be acknowledged by ED staff, and privacy provided to allow for grieving; (iii) Prolonged waiting time for an urgent medical condition; and (iv) Ongoing care and support, such as providing recommendations of available services to support patients on discharge from the ED. CONCLUSION: Early pregnancy bleeding is a distressing and anxiety-provoking experience for women attending the ED. Appropriate emotional support is critical to the holistic care for those seeking emergency care.

The Australasian Resuscitation In Sepsis Evaluation: FLUid or vasopressors In Emergency Department Sepsis, a multicentre observational study (ARISE FLUIDS observational study): Rationale, methods and analysis plan.

OBJECTIVE: There is uncertainty about the optimal i.v. fluid volume and timing of vasopressor commencement in the resuscitation of patients with sepsis and hypotension. We aim to study current resuscitation practices in EDs in Australia and New Zealand (the Australasian Resuscitation In Sepsis Evaluation: FLUid or vasopressors In Emergency Department Sepsis [ARISE FLUIDS] observational study). METHODS: ARISE FLUIDS is a prospective, multicentre observational study in 71 hospitals in Australia and New Zealand. It will include adult patients presenting to the ED during a 30 day period with suspected sepsis and hypotension (systolic blood pressure <100 mmHg) despite at least 1000 mL fluid resuscitation. We will obtain data on baseline demographics, clinical and laboratory variables, all i.v. fluid given in the first 24 h, vasopressor use, time to antimicrobial administration, admission to intensive care, organ failure and in-hospital mortality. We will specifically describe (i) the volume of fluid administered at the following time points: when meeting eligibility criteria, in the first 6 h, at 24 h and prior to vasopressor commencement and (ii) the frequency and timing of vasopressor use in the first 6 h and at 24 h. Screening logs will provide reliable estimates of the proportion of ED patients meeting eligibility criteria for a subsequent randomised controlled trial. DISCUSSION: This multicentre, observational study will provide insight into current haemodynamic resuscitation practices in patients with sepsis and hypotension as well as estimates of practice variation and patient outcomes. The results will inform the design and feasibility of a multicentre phase III trial of early haemodynamic resuscitation in patients presenting to ED with sepsis and hypotension.

Time to establish pillars in point-of-care ultrasound.

Point of care ultrasound (PoCUS) has evolved rapidly and is used by many medical specialties. We propose five essential pillars of PoCUS that are necessary framework for hospital-based PoCUS training and credentialing programs. The pillars are: governance, infrastructure, administration, education and quality. It is time to establish these pillars to ensure the best practice in PoCUS use.

Randomized Placebo-controlled Trial of Droperidol and Ondansetron for Adult Emergency Department Patients With Nausea.

OBJECTIVE: The objective was to separately compare effectiveness of 1.25 mg of intravenous (IV) droperidol and 8 mg of IV ondansetron with 0.9% saline placebo for adult emergency department (ED) patients with nausea. A novel primary outcome measure, expected to aid clinical interpretation of reported results, was employed. METHODS: A randomized controlled trial was conducted at the three EDs of Monash Health, Melbourne, Australia. The design was to demonstrate superiority of the active drugs over placebo. The primary outcome measure of symptom improvement was defined as a visual analog scale (VAS) rating change of -8 mm or more from baseline at 30 minutes posttreatment. Mean VAS changes per group and percentages experiencing the desired treatment effect were also compared. The study was concluded after recruitment of 215 of the planned 378 patients, as interim analysis confirmed that continuation could not result in a finding of superiority. RESULTS: Of 215 patients, 73 (34%), 71 (33%), and 71 (33%) received droperidol, ondansetron, and placebo. Symptom improvement occurred in 75% (95% confidence interval [CI] = 64% to 85%), 80% (95% CI = 69% to 89%), and 76% (95% CI = 64% to 85%), respectively. Mean VAS changes were -29 mm (95% CI = -36 to -23 mm), -34 mm (95% CI = -41 to -28 mm), and -24 mm (95% CI = -29 to -19 mm), respectively. Desired treatment effects were experienced by 77% (95% CI = 65% to 86%), 73% (95% CI = 61% to 83%), and 59% (95% CI = 47% to 71%), respectively. CONCLUSION: For adult ED patients with nausea, superiority was not demonstrated for droperidol or ondansetron over placebo.

Collaborative model for training and credentialing point-of-care ultrasound: 6-year experience and quality outcomes.

INTRODUCTION: Point-of-care ultrasound (PoCUS) is a rapidly growing area, providing physicians with a valuable diagnostic tool for patient assessment. This paper describes a collaborative model, utilising radiology department ultrasound expertise, to train and credential physicians in PoCUS. A 6-year experience of the implementation and outcomes of the programme established within the emergency departments of a large, multi-campus hospital network are presented. METHODS: A collaborative model was initially developed and implemented between radiology and emergency departments. Key elements of the programme included hospital executive support, close collaboration with stakeholders, resource allocation, appointment of a sonographer educator, clear scope of practise and robust quality processes. RESULTS: Participation grew from 36 emergency physicians in 2011 to 96 physicians in 2016. A total 11064 scans were logged with the programme in the 6-year period. Routine quality audit of 61.8% (6836/11064) of all scans included 2836 Focussed Assessment by Sonography in Trauma (FAST) and 1422 Abdominal Aortic Aneurysm (AAA) examinations. False-positive or false-negative diagnoses occurred in 3.6% (102/2836) FAST and 1.3% (19/1422) AAA cases. No adverse clinical outcomes were reported to involve programme-compliant scans. CONCLUSION: A collaborative model to train and credential physicians in PoCUS has been successfully implemented. The programme grew significantly, produced excellent quality outcomes and resolved many issues of potential conflict related to PoCUS.

Correction: RESPECT-ED: Rates of Pulmonary Emboli (PE) and Sub-Segmental PE with Modern Computed Tomographic Pulmonary Angiograms in Emergency Departments: A Multi-Center Observational Study Finds Significant Yield Variation, Uncorrelated with Use or Small PE Rates.

[This corrects the article DOI: 10.1371/journal.pone.0166483.].

Introduction of a new imaging guideline for suspected renal colic in the ED reduces CT urography utilisation.

BACKGROUND: Patients presenting to the ED with suspected renal colic are frequently imaged with CT urography (CTU), which rarely alters diagnosis or management. To reduce use of CTU in this population, we instigated a new imaging and management guideline in our ED. METHODS: This was a quasi-experimental prospective study, whereby a new guideline was commenced at the intervention site (Monash Medical Centre) and the existing guideline continued at the control site (Dandenong Hospital). The new guideline promotes focused ultrasound for diagnosing renal colic and restricts CT to those with poor response to analgesia or 'red flags'. A consecutive series of patients with suspected renal colic were prospectively enrolled and outcomes compared between the sites. The primary outcome was CTU utilisation and secondary outcomes were radiation exposure, stone rate on CTU, admission, ED length of stay and rates of urological intervention and returns to ED at 4-week follow-up. RESULTS: Preintervention CTU rates were 76.7% at Monash and 72.1% at Dandenong. 324 patients were enrolled; 148 at Monash and 176 at Dandenong. Median age 47 years vs 49 years, males 76.4% vs 66.5% and medianSex, Timing, Origin, Nausea, Erythrocytes (STONE) score 10 vs 10 for Monash and Dandenong, respectively. CTU was performed in 54.1% vs 75.0% (p<0.001), median radiation exposure 2.8 vs 4.0 mSv (p<0.001) and urological intervention occurred in 16.4% vs 15.7% for Monash and Dandenong, respectively. CONCLUSIONS: We found that use of CTU for renal colic was significantly reduced by introduction of a guideline promoting ultrasound and encouraging selective CTU. Although intervention rates were similar between the two sites, further prospective study is needed to ensure other patient-centred outcomes do not differ.

Survival in Out-of-hospital Rapid Sequence Intubation of Non-Traumatic Brain Pathologies.

INTRODUCTION: Rapid sequence intubation (RSI) is not only used in traumatic brain injuries in the out-of-hospital setting, but also for non-traumatic brain pathologies (NTBP) such as brain tumors, meningitis, encephalitis, hypoxic/anoxic brain injury, stroke, arteriovenous malformations, tumors, aneurysms, brain hemorrhage, as well as brain injury due to diabetes, seizures and toxicity, metabolic conditions, and alcohol and drug overdose. Previous research suggests that RSI is common in non-traumatic coma, but with an unknown prevalence of NTBP in those that receive RSI. If NTBP is common and if brain trauma RSI evidence is not valid for NTBP then a sizable proportion of NTBP receive this treatment without evidence of benefit. This study calculated the out-of-hospital NTBP prevalence in patients that had received RSI and explored factors that predicted survival. METHODS: A retrospective cohort study based on data collected from an ambulance service and seven hospitals based in Melbourne, Australia. Non-traumatic brain pathologies were defined using ICD10-AM codes for the calculation of NTBP prevalence. Logistic regression modelled out-of-hospital predictors of survival to hospital discharge after adjustment for comorbidities. RESULTS: The seven participating hospitals treated 2,277 patients that received paramedic RSI for all illnesses and indications from January 1, 2008 to December 31, 2015, with survival data available for 1,940 (85%). Of the 1,940, 1,125 (58%) patients had at least one hospital-diagnosed NTBP. Sixty-nine percent all of NTBP survived to hospital discharge, compared to 65% for traumatic intracranial injury. Strokes were the most common and had poor survival to discharge (37%) compared to the second most common NTBP toxicity/toxic encephalopathy that had very high survival (98%). No out-of-hospital clinical intervention or prehospital time interval predicted survival. Factors that did predict survival include Glasgow Coma Scale (GCS), duration of mechanical ventilation, age, ICU length of stay, and comorbidities. CONCLUSIONS: Non-traumatic brain pathologies are seven times more prevalent than traumatic brain injuries in patients that underwent out-of-hospital RSI in Victoria, Australia. Since the mechanisms through which RSI impacts mortality might differ between traumatic brain injuries and NTBP, and given that NTBP is very prevalent, it follows that the use of RSI in NTBP could be unsupported.