Safety and Efficacy of Prehospital Diltiazem for Atrial Fibrillation with Rapid Ventricular Response.

INTRODUCTION: Atrial fibrillation (AFIB) with rapid ventricular response (RVR) is a common tachydysrhythmia encountered by Emergency Medical Services (EMS). Current guidelines suggest rate control in stable, symptomatic patients. PROBLEM: Little is known about the safety or efficacy of rate-controlling medications given by prehospital providers. This study assessed a protocol for prehospital administration of diltiazem in the setting of AFIB with RVR for provider protocol compliance, patient clinical improvement, and associated adverse events. METHODS: This was a retrospective, cohort study of patients who were administered diltiazem by providers in the Orange County EMS System (Florida USA) over a two-year period. The protocol directed a 0.25mg/kg dose of diltiazem (maximum of 20mg) for stable, symptomatic patients in AFIB with RVR at a rate of >150 beats per minute (bpm) with a narrow complex. Data collected included patient characteristics, vital signs, electrocardiogram (ECG) rhythm before and after diltiazem, and need for rescue or additional medications. Adverse events were defined as systolic blood pressure <90mmHg or administration of intravenous fluid after diltiazem administration. Clinical improvement was defined as a heart rate decreased by 20% or less than 100bmp. Original prehospital ECG rhythm interpretations were compared to physician interpretations performed retrospectively. RESULTS: Over the study period, 197 patients received diltiazem, with 131 adhering to the protocol. The initial rhythm was AFIB with RVR in 93% of the patients (five percent atrial flutter, two percent supraventricular tachycardia, and one percent sinus tachycardia). The agreement between prehospital and physician rhythm interpretation was 92%, with a Kappa value of 0.454 (P <.001). Overall, there were 22 (11%) adverse events, and 112 (57%) patients showed clinical improvement. When diltiazem was given outside of the existing protocol, the patients had higher rates of adverse events (18% versus eight percent; P = .033). Patients who received diltiazem in adherence with protocols were more likely to show clinical improvement (63% versus 46%; P = .031). CONCLUSION: This study suggests that prehospital diltiazem administration for AFIB with RVR is safe and effective when strict protocols are followed.Rodriguez A, Hunter CL, Premuroso C, Silvestri S, Stone A, Miller S, Zuver C, Papa L. Safety and efficacy of prehospital diltiazem for atrial fibrillation with rapid ventricular response. Prehosp Disaster Med. 2019;34(3):297-302.

Prehospital sepsis alert notification decreases time to initiation of CMS sepsis core measures.

OBJECTIVE: To determine if prehospital identification of sepsis will affect time to Centers for Medicare and Medicaid services (CMS) sepsis core measures and improve clinical outcomes. METHODS: We conducted a retrospective cohort study among septic patients who were identified as "sepsis alerts" in the emergency department (ED). Metrics including time from ED registration to fluid resuscitation, blood cultures, serum lactate draws, and antibiotics administration were compared between those who had pre-arrival notification by EMS versus those that did not. Additionally, outcomes such as mortality and intensive care unit (ICU) admission were recorded. RESULTS: Of the 272 total patients, 162 had pre-arrival notification (prehospital sepsis alerts) and 110 did not. The prehospital sepsis alert group had significantly lower times to intravenous fluid administration (6 min 95%CI 4-9 min vs 41 min 95%CI 24-58 min, p < 0.001), blood cultures drawn (12 min 95%CI 10-14 min vs 34 min 95%CI 20-48 min, p = 0.003), lactate levels drawn (12 min 95%CI 10-15 min vs 34 min 95%CI 20-49 min, p = 0.003), and administration of antibiotics (33 min 95%CI 26-40 min vs 61 min 95%CI 44-78 min, p = 0.004). Patients with prehospital sepsis alerts also had a higher admission rate (100% vs 95%, p = 0.006), and a lower ICU admission rate (33% vs 52%, p = 0.003). There was no difference in mortality (11% vs 14%, p = 0.565) between groups. CONCLUSIONS: Prehospital sepsis alert notification may decrease time to specific metrics shown to improve outcomes in sepsis.

Comparing Quick Sequential Organ Failure Assessment Scores to End-tidal Carbon Dioxide as Mortality Predictors in Prehospital Patients with Suspected Sepsis.

INTRODUCTION: Early identification of sepsis significantly improves outcomes, suggesting a role for prehospital screening. An end-tidal carbon dioxide (ETCO2) value ≤ 25 mmHg predicts mortality and severe sepsis when used as part of a prehospital screening tool. Recently, the Quick Sequential Organ Failure Assessment (qSOFA) score was also derived as a tool for predicting poor outcomes in potentially septic patients. METHODS: We conducted a retrospective cohort study among patients transported by emergency medical services to compare the use of ETCO2 ≤ 25 mmHg with qSOFA score of ≥ 2 as a predictor of mortality or diagnosis of severe sepsis in prehospital patients with suspected sepsis. RESULTS: By comparison of receiver operator characteristic curves, ETCO2 had a higher discriminatory power to predict mortality, sepsis, and severe sepsis than qSOFA. CONCLUSION: Both non-invasive measures were easily obtainable by prehospital personnel, with ETCO2 performing slightly better as an outcome predictor.

Prehospital End-tidal Carbon Dioxide Predicts Mortality in Trauma Patients.

BACKGROUND: End-tidal carbon dioxide (EtCO2) measurement has been shown to have prognostic value in acute trauma. OBJECTIVE: Evaluate the association of prehospital EtCO2 and in-hospital mortality in trauma patients and to assess its prognostic value when compared to traditional vital signs. METHODS: Retrospective, cross-sectional study of patients transported by a single EMS agency to a level one trauma center. We evaluated initial out-of-hospital vital signs documented by EMS personnel including EtCO2, respiratory rate (RR), systolic BP (SBP), diastolic BP (DBP), pulse (P), and oxygen saturation (O2) and hospital data. The main outcome measure was mortality. RESULTS: 135 trauma patients were included; 9 (7%) did not survive. The mean age of patients was 40 (SD17) [Range 16-89], 97 (72%) were male, 76 (56%) were admitted to the hospital and 15 (11%) went to the ICU. The mean EtCO2 level was 18 mmHg (95%CI 9-28) [Range 5-41] in non-survivors compared to 34 mmHg (95%CI 32-35) [Range 11-51] in survivors. The area under the ROC curve (AUC) for EtCO2 in predicting mortality was 0.84 (0.67-1.00) (p = 0.001), RR was 0.82 (0.63-1.00), SBP was 0.72 (0.49-0.96), DBP was 0.72 (0.47-0.97), pulse was 0.51 (0.26-0.76), and O2 was 0.64 (0.37-0.91). Cut-off values at 30 mmHg yielded sensitivity = 89% (51-99), specificity = 68% (59-76), PPV = 13% (6-24) and NPV = 99% (93-100) for predicting mortality. There was no correlation between RR and EtCO2 (correlation 0.16; p = 0.06). CONCLUSION: We found an inverse association between prehospital EtCO2 and mortality. This has implications for improving triage and assisting EMS in directing patients to an appropriate trauma center.

Comparison of START and SALT triage methodologies to reference standard definitions and to a field mass casualty simulation.

OBJECTIVES: We compared Sort, Assess, Lifesaving Intervention, Treatment/Transport (SALT) and Simple Triage and Rapid Treatment (START) triage methodologies to a published reference standard, and evaluated the accuracy of the START method applied by emergency medical services (EMS) personnel in a field simulation. DESIGN: Simulated mass casualty incident (MCI). Paramedics trained in START triage assigned each victim to green (minimal), yellow (delayed), red (immediate), or black (dead) categories. These victim classifications were recorded by investigators and compared to reference standard definitions of each triage category. The victim scenarios were also compared to the a priori classifications as developed by the investigators. SETTING: MCI field simulation. MAIN OUTCOME MEASURE: Comparison of the correlation of START and SALT triage methodologies to reference standard definitions. Another outcome measure was the accuracy of the application of START triage by EMS personnel in the field exercise. RESULTS: The strongest correlation to the reference standard was SALT with an r = 0.860 (p < 0.001) and κ = 0.632 (p < 0.001). START and SALT triage systems agreed 100 percent on both black and green classifications. There were significant correlations between the field triage and both START and SALT methods (p < 0.001, respectfully). SALT had a significantly lower undertriage rate (9 percent [95%CI 2-15]) than both START (20 percent [95%CI 11-28]) and field triage (37 percent [95%CI 24-52]). There were no significant differences in overtriage rates. CONCLUSIONS: In our study, the SALT triage system was overall more accurate triage method than START at classi-fying patients, specifically in the delayed and immediate categories. In our field exercise, paramedic use of the START methodology yielded a higher rate of undertriage compared to the SALT classification.

Association between EMS Question Bank Completion and Passing Rates on the EMS Certification Examination.

INTRODUCTION: A board review question bank was created to assist candidates in their preparation for the 2015 EMS certification examination. We aimed to describe the development of this question bank and evaluate its successes in preparing candidates to obtain EMS subspecialty board certification. METHODS: An online question bank was developed by 13 subject matter experts who participated as item writers, representing eight different EMS fellowship programs. The online question bank consisted of four practice tests, with each of the tests comprised of 100 questions. The number of candidates who participated in and completed the question bank was calculated. The passing rate among candidates who completed the question bank was calculated and compared to the publicly reported statistics for all candidates. The relationship between candidates' performance on the question bank and subspecialty exam pass rates was determined. RESULTS: A total of 252 candidates took at least one practice test and, of those, 225 candidates completed all four 100-question practice tests. The pass rate on the 2015 EMS certification exam was 79% (95%CI 74-85%) among candidates who completed the question bank, which is 12% higher than the overall pass rate (p = 0.003). Candidates' performance on the question bank was positively associated with overall success on the exam (X2 = 75.8, p < 0.0001). Achieving a score of ≥ 70% on the question bank was associated with a higher likelihood of passing the exam (OR = 17.8; 95% CI: 8.0-39.6). CONCLUSION: Completing the question bank program was associated with improved pass rates on the EMS certification exam. Strong performance on the question bank correlated with success on the exam.

Neuronal Biomarker Ubiquitin C-Terminal Hydrolase Detects Traumatic Intracranial Lesions on Computed Tomography in Children and Youth with Mild Traumatic Brain Injury.

This study examined the performance of serum ubiquitin C-terminal hydrolase (UCH-L1) in detecting traumatic intracranial lesions on computed tomography (CT) scan (+CT) in children and youth with mild and moderate TBI (mmTBI) and assessed its performance in trauma control patients without head trauma. This prospective cohort study enrolled children and youth presenting to three level 1 trauma centers after blunt head trauma and a Glasgow Coma Scale (GCS) score of 9-15 as well as trauma control patients with GCS 15 that did not have blunt head trauma. The primary outcome measure was the presence of intracranial lesions on initial CT scan. Blood samples were obtained in all patients within 6 h of injury and measured by enzyme-linked immunosorbent assay ELISA for UCH-L1 (ng/mL). A total of 256 children and youth were enrolled in the study and had serum samples drawn within 6 h of injury for analysis; 196 had blunt head trauma and 60 were trauma controls. CT scan of the head was performed in 151 patients and traumatic intracranial lesions on CT scan were evident in 17 (11%), all of whom had a GCS of 13-15. The area under the receiver operating characteristic curve (AUC) for UCH-L1 in detecting children and youth with traumatic intracranial lesions on CT was 0.83 (95% confidence interval [CI], 0.73-0.93). In those presenting with a GCS of 15, the AUC for detecting lesions was 0.83 (95% CI, 0.72-0.94). Similarly, in children under 5 years of age, the AUC was 0.79 (95% CI, 0.59-1.00). Performance for detecting intracranial lesions at a UCH-L1 cut-off level of 0.18 ng/mL yielded a sensitivity of 100%, a specificity of 47%, and a negative predictive value of 100%. UCH-L1 showed good performance in infants and toddlers younger than 5 years and performed well in children and youth with a GCS score of 15. Before clinical application, further study in larger cohort of children and youth with mild TBI is warranted.

Endotracheal tube placement confirmation: 100% sensitivity and specificity with sustained four-phase capnographic waveforms in a cadaveric experimental model.

BACKGROUND: Waveform capnography is considered the gold standard for verification of proper endotracheal tube placement, but current guidelines caution that it is unreliable in low-perfusion states such as cardiac arrest. Recent case reports found that long-deceased cadavers can produce capnographic waveforms. The purpose of this study was to determine the predictive value of waveform capnography for endotracheal tube placement verification and detection of misplacement using a cadaveric experimental model. METHODS: We conducted a controlled experiment with two intubated cadavers. Tubes were placed within the trachea, esophagus, and hypopharynx utilizing video laryngoscopy. We recorded observations of capnographic waveforms and quantitative end-tidal carbon dioxide (ETCO2) values during tracheal versus extratracheal (i.e., esophageal and hypopharyngeal) ventilations. RESULTS: 106 and 89 tracheal ventilations delivered to cadavers one and two, respectively (n=195) all produced characteristic alveolar waveforms (positive) with ETCO2 values ranging 2-113mmHg. 42 esophageal ventilations (36 to cadaver one and 6 to cadaver two), and 6 hypopharyngeal ventilations (4 to cadaver one and 2 to cadaver two) all resulted in non-alveolar waveforms (negative) with ETCO2 values of 0mmHg. Esophageal and hypopharyngeal measurements were categorized as extratracheal (n=48). A binary classification test showed no false negatives or false positives, indicating 100% sensitivity (NPV 1.0, 95%CI 0.98-1.00) and 100% specificity (PPV 1.0, 95%CI 0.93-1.00). CONCLUSION: Though current guidelines question the reliability of waveform capnography for verifying endotracheal tube location during low-perfusion states such as cardiac arrest, our findings suggest that it is highly sensitive and specific.

Time Course and Diagnostic Accuracy of Glial and Neuronal Blood Biomarkers GFAP and UCH-L1 in a Large Cohort of Trauma Patients With and Without Mild Traumatic Brain Injury.

IMPORTANCE: Glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase L1 (UCH-L1) have been widely studied and show promise for clinical usefulness in suspected traumatic brain injury (TBI) and concussion. Understanding their diagnostic accuracy over time will help translate them into clinical practice. OBJECTIVES: To evaluate the temporal profiles of GFAP and UCH-L1 in a large cohort of trauma patients seen at the emergency department and to assess their diagnostic accuracy over time, both individually and in combination, for detecting mild to moderate TBI (MMTBI), traumatic intracranial lesions on head computed tomography (CT), and neurosurgical intervention. DESIGN, SETTING, AND PARTICIPANTS: This prospective cohort study enrolled adult trauma patients seen at a level I trauma center from March 1, 2010, to March 5, 2014. All patients underwent rigorous screening to determine whether they had experienced an MMTBI (blunt head trauma with loss of consciousness, amnesia, or disorientation and a Glasgow Coma Scale score of 9-15). Of 3025 trauma patients assessed, 1030 met eligibility criteria for enrollment, and 446 declined participation. Initial blood samples were obtained in 584 patients enrolled within 4 hours of injury. Repeated blood sampling was conducted at 4, 8, 12, 16, 20, 24, 36, 48, 60, 72, 84, 96, 108, 120, 132, 144, 156, 168, and 180 hours after injury. MAIN OUTCOMES AND MEASURES: Diagnosis of MMTBI, presence of traumatic intracranial lesions on head CT scan, and neurosurgical intervention. RESULTS: A total of 1831 blood samples were drawn from 584 patients (mean [SD] age, 40 [16] years; 62.0% [362 of 584] male) over 7 days. Both GFAP and UCH-L1 were detectible within 1 hour of injury. GFAP peaked at 20 hours after injury and slowly declined over 72 hours. UCH-L1 rose rapidly and peaked at 8 hours after injury and declined rapidly over 48 hours. Over the course of 1 week, GFAP demonstrated a diagnostic range of areas under the curve for detecting MMTBI of 0.73 (95% CI, 0.69-0.77) to 0.94 (95% CI, 0.78-1.00), and UCH-L1 demonstrated a diagnostic range of 0.30 (95% CI, 0.02-0.50) to 0.67 (95% CI, 0.53-0.81). For detecting intracranial lesions on CT, the diagnostic ranges of areas under the curve were 0.80 (95% CI, 0.67-0.92) to 0.97 (95% CI, 0.93-1.00)for GFAP and 0.31 (95% CI, 0-0.63) to 0.77 (95% CI, 0.68-0.85) for UCH-L1. For distinguishing patients with and without a neurosurgical intervention, the range for GFAP was 0.91 (95% CI, 0.79-1.00) to 1.00 (95% CI, 1.00-1.00), and the range for UCH-L1 was 0.50 (95% CI, 0-1.00) to 0.92 (95% CI, 0.83-1.00). CONCLUSIONS AND RELEVANCE: GFAP performed consistently in detecting MMTBI, CT lesions, and neurosurgical intervention across 7 days. UCH-L1 performed best in the early postinjury period.

A prehospital screening tool utilizing end-tidal carbon dioxide predicts sepsis and severe sepsis.

OBJECTIVE: To determine the utility of a prehospital sepsis screening protocol utilizing systemic inflammatory response syndrome (SIRS) criteria and end-tidal carbon dioxide (ETCO2). METHODS: We conducted a prospective cohort study among sepsis alerts activated by emergency medical services during a 12 month period after the initiation of a new sepsis screening protocol utilizing ≥2 SIRS criteria and ETCO2 levels of ≤25 mmHg in patients with suspected infection. The outcomes of those that met all criteria of the protocol were compared to those that did not. The main outcome was the diagnosis of sepsis and severe sepsis. Secondary outcomes included mortality and in-hospital lactate levels. RESULTS: Of 330 sepsis alerts activated, 183 met all protocol criteria and 147 did not. Sepsis alerts that followed the protocol were more frequently diagnosed with sepsis (78% vs 43%, P < .001) and severe sepsis (47% vs 7%, P < .001), and had a higher mortality (11% vs 5%, P = .036). Low ETCO2 levels were the strongest predictor of sepsis (area under the ROC curve (AUC) of 0.99, 95% CI 0.99-1.00; P < .001), severe sepsis (AUC 0.80, 95% CI 0.73-0.86; P < .001), and mortality (AUC 0.70, 95% CI 0.57-0.83; P = .005) among all prehospital variables. Sepsis alerts that followed the protocol had a sensitivity of 90% (95% CI 81-95%), a specificity of 58% (95% CI 52-65%), and a negative predictive value of 93% (95% CI 87-97%) for severe sepsis. There were significant associations between prehospital ETCO2 and serum bicarbonate levels (r = 0.415, P < .001), anion gap (r = -0.322, P < .001), and lactate (r = -0.394, P < .001). CONCLUSION: A prehospital screening protocol utilizing SIRS criteria and ETCO2 predicts sepsis and severe sepsis, which could potentially decrease time to therapeutic intervention.

In Children and Youth with Mild and Moderate Traumatic Brain Injury, Glial Fibrillary Acidic Protein Out-Performs S100ß in Detecting Traumatic Intracranial Lesions on Computed Tomography.

In adults, glial fibrillary acidic protein (GFAP) has been shown to out-perform S100ß in detecting intracranial lesions on computed tomography (CT) in mild traumatic brain injury (TBI). This study examined the ability of GFAP and S100ß to detect intracranial lesions on CT in children and youth involved in trauma. This prospective cohort study enrolled a convenience sample of children and youth at two pediatric and one adult Level 1 trauma centers following trauma, including both those with and without head trauma. Serum samples were obtained within 6 h of injury. The primary outcome was the presence of traumatic intracranial lesions on CT scan. There were 155 pediatric trauma patients enrolled, 114 (74%) had head trauma and 41 (26%) had no head trauma. Out of the 92 patients who had a head CT, eight (9%) had intracranial lesions. The area under the receiver operating characteristic curve (AUC) for distinguishing head trauma from no head trauma for GFAP was 0.84 (0.77-0.91) and for S100ß was 0.64 (0.55-0.74; p<0.001). Similarly, the AUC for predicting intracranial lesions on CT for GFAP was 0.85 (0.72-0.98) versus 0.67 (0.50-0.85) for S100ß (p=0.013). Additionally, we assessed the performance of GFAP and S100ß in predicting intracranial lesions in children ages 10 years or younger and found the AUC for GFAP was 0.96 (95% confidence interval [CI] 0.86-1.00) and for S100ß was 0.72 (0.36-1.00). In children younger than 5 years old, the AUC for GFAP was 1.00 (95% CI 0.99-1.00) and for S100ß 0.62 (0.15-1.00). In this population with mild TBI, GFAP out-performed S100ß in detecting head trauma and predicting intracranial lesions on head CT. This study is among the first published to date to prospectively compare these two biomarkers in children and youth with mild TBI.

Performance of Glial Fibrillary Acidic Protein in Detecting Traumatic Intracranial Lesions on Computed Tomography in Children and Youth With Mild Head Trauma.

OBJECTIVES: This study examined the performance of serum glial fibrillary acidic protein (GFAP) in detecting traumatic intracranial lesions on computed tomography (CT) scan in children and youth with mild and moderate traumatic brain injury (TBI) and assessed its performance in trauma control patients without head trauma. METHODS: This prospective cohort study enrolled children and youth presenting to three Level I trauma centers following blunt head trauma with Glasgow Coma Scale (GCS) scores of 9 to 15, as well as trauma control patients with GCS scores of 15 who did not have blunt head trauma. The primary outcome measure was the presence of intracranial lesions on initial CT scan. Blood samples were obtained in all patients within 6 hours of injury and measured by enzyme-linked immunosorbent assay for GFAP (ng/mL). RESULTS: A total of 257 children and youth were enrolled in the study and had serum samples drawn within 6 hours of injury for analysis: 197 had blunt head trauma and 60 were trauma controls. CT scan of the head was performed in 152 patients and traumatic intracranial lesions on CT scan were evident in 18 (11%), all of whom had GCS scores of 13 to 15. When serum levels of GFAP were compared in children and youth with traumatic intracranial lesions on CT scan to those without CT lesions, median GFAP levels were significantly higher in those with intracranial lesions (1.01, interquartile range [IQR] = 0.59 to 1.48) than those without lesions (0.18, IQR = 0.06 to 0.47). The area under the receiver operating characteristic curve (AUC) for GFAP in detecting children and youth with traumatic intracranial lesions on CT was 0.82 (95% confidence interval [CI] = 0.71 to 0.93). In those presenting with GCS scores of 15, the AUC for detecting lesions was 0.80 (95% CI = 0.68 to 0.92). Similarly, in children under 5 years old the AUC was 0.83 (95% CI = 0.56 to 1.00). Performance for detecting intracranial lesions at a GFAP cutoff level of 0.15 ng/mL yielded a sensitivity of 94%, a specificity of 47%, and a negative predictive value of 98%. CONCLUSIONS: In children and youth of all ages, GFAP measured within 6 hours of injury was associated with traumatic intracranial lesions on CT and with severity of TBI. Further study is required to validate these findings before clinical application.

Feasibility and accuracy of using mobile phone images of electrocardiograms to initiate the cardiac catheterization process.

We assessed the feasibility of interpreting the presence of ST-segment elevation myocardial infarction (STEMI) using ECGs captured and transmitted by mobile phones. Transmitted ECGs were interpreted by four independent and blinded physicians, who classified them as STEMI, non-STEMI or indeterminate. After 2-4 weeks the same physicians were given the original paper ECGs for interpretation. In total, 87 ECGs were randomly selected for review. The overall agreement between the digital image readings and the printed copy readings was 94%. Of the 87 patients, 65 (75%) had cardiac catheterization following a STEMI ECG and 22 (25%) did not receive cardiac catheterization. The accuracy of digital ECGs and printed ECGs when compared to the findings from cardiac catheterization was similar. Agreement in ECG interpretations between printed images and mobile phone images was excellent, and both had similar accuracy in activating the cardiac catheterization laboratory. Mobile phone transmission is an inexpensive method of evaluating ECG images sent from pre-hospital settings to the emergency department.

Prehospital end-tidal carbon dioxide differentiates between cardiac and obstructive causes of dyspnoea.

BACKGROUND: Differentiating between cardiac and obstructive causes for dyspnoea is essential for proper management, but is difficult in the prehospital setting. OBJECTIVE: To assess if prehospital levels of end-tidal carbon dioxide (ETCO2) differed in obstructive compared to cardiac causes of dyspnoea, and could suggest one diagnosis over the other. METHODS: We conducted a retrospective cohort study among patients transported by emergency medical services during a 29-month period who were diagnosed with either obstructive pulmonary disease or congestive heart failure (CHF) by ICD-9 codes. Initial prehospital vital signs, including ETCO2, were recorded. Records were linked by manual archiving of emergency medical services and hospital data. RESULTS: There were 106 patients with a diagnosis of obstructive or cardiac causes of dyspnoea that had prehospital ETCO2 levels measured during the study period. ETCO2 was significantly lower in patients diagnosed with CHF (31 mm Hg 95% CI 27 to 35) versus obstructive pulmonary disease (39 mm Hg 95% CI 35 to 42; p<0.001). Lower ETCO2 levels predicted CHF, with an area under the Receiver Operating Characteristics Curve of 0.70 (95% CI 0.60 to 0.81). Using ETCO2 <40 mm Hg as a cut-off, the sensitivity for predicting heart failure was 93% (95% CI 88% to 98%), the specificity was 43% (95% CI 33% to 52%), the positive predictive value was 38% (95% CI 29% to 48%), and the negative predictive value was 94% (95% CI 89% to 99%). CONCLUSIONS: Lower levels of ETCO2 were associated with CHF, and may serve as an objective diagnostic adjunct to predict this cause of dyspnoea in the prehospital setting.

GFAP out-performs S100ß in detecting traumatic intracranial lesions on computed tomography in trauma patients with mild traumatic brain injury and those with extracranial lesions.

Both glial fibrillary acidic protein (GFAP) and S100ß are found in glial cells and are released into serum following a traumatic brain injury (TBI), however, the clinical utility of S100ß as a biomarker has been questioned because of its release from bone. This study examined the ability of GFAP and S100ß to detect intracranial lesions on computed tomography (CT) in trauma patients and also assessed biomarker performance in patients with fractures and extracranial injuries on head CT. This prospective cohort study enrolled a convenience sample of adult trauma patients at a Level I trauma center with and without mild or moderate traumatic brain injury (MMTBI). Serum samples were obtained within 4 h of injury. The primary outcome was the presence of traumatic intracranial lesions on CT scan. There were 397 general trauma patients enrolled: 209 (53%) had a MMTBI and 188 (47%) had trauma without MMTBI. Of the 262 patients with a head CT, 20 (8%) had intracranial lesions. There were 137 (35%) trauma patients who sustained extracranial fractures below the head to the torso and extremities. Levels of S100ß were significantly higher in patients with fractures, compared with those without fractures (p<0.001) whether MMTBI was present or not. However, GFAP levels were not significantly affected by the presence of fractures (p>0.05). The area under the receiver operating characteristics curve (AUC) for predicting intracranial lesions on CT for GFAP was 0.84 (0.73-0.95) and for S100ß was 0.78 (0.67-0.89). However, in the presence of extracranial fractures, the AUC for GFAP increased to 0.93 (0.86-1.00) and for S100ß decreased to 0.75 (0.61-0.88). In a general trauma population, GFAP out-performed S100ß in detecting intracranial CT lesions, particularly in the setting of extracranial fractures.

The sixth vital sign: prehospital end-tidal carbon dioxide predicts in-hospital mortality and metabolic disturbances.

OBJECTIVE: To determine the ability of prehospital end-tidal carbon dioxide (ETCO2) to predict in-hospital mortality compared to conventional vital signs. METHODS: We conducted a retrospective cohort study among patients transported by emergency medical services during a 29-month period. Included patients had ETCO2 recorded in addition to initial vital signs. The main outcome was death at any point during hospitalization. Secondary outcomes included laboratory results and admitting diagnosis. RESULTS: Of 1328 records reviewed, hospital discharge data, ETCO2, and all 6 prehospital vital signs were available in 1088 patients. Low ETCO2 levels were the strongest predictor of mortality in the overall group (area under the receiver operating characteristic curve (AUC of 0.76, 95% confidence interval [CI] 0.66-0.85), as well as subgroup analysis excluding prehospital cardiac arrest (AUC of 0.77, 95% CI 0.67-0.87). The sensitivity of abnormal ETCO2 for predicting mortality was 93% (95% CI 79%-98%), the specificity was 44% (95% CI 41%-48%), and the negative predictive value was 99% (95% CI 92%-100%). There were significant associations between ETCO2 and serum bicarbonate levels (r = 0.429, P < .001), anion gap (r = -0.216, P < .001), and lactate (r = -0.376, P < .001). CONCLUSION: Of all prehospital vital signs, ETCO2 was the most predictive and consistent for mortality, which may be related to an association with metabolic acidosis.

Evaluation of an off-the-shelf mobile telemedicine model in emergency department wound assessment and management.

We examined the agreement between a videoconference-based evaluation and a bedside evaluation in the management of acute traumatic wounds in an emergency department. Adult and paediatric patients with acute wounds of various severities to the face, trunk and/or extremities presenting to the emergency department within 24 hours of injury were enrolled. Research assistants transmitted video images of the wound to an emergency physician using a laptop computer. The physician completed a standard wound assessment form before conducting a bedside evaluation and then completing a second assessment form. The primary outcome measure was wound length and depth. We also assessed management decision-making. A total of 173 wounds were evaluated. The correlation coefficient between video and bedside assessments was 0.96 for wound length. The mean difference between the lengths was 0.02 cm (SD 0.91). Management of the wound would have been the same in 94% of cases. The agreement on wound characteristics and wound management ranged from 84-100%. The highest correlation was 0.92 in suture material used and the lowest correlation was 0.64 in wound type. The ability of video images to distinguish between a minor and non-minor wound, and predicting the need for hospital management, had high degrees of sensitivity and specificity. The study showed that wound characteristics and management decisions appear to correlate well between video and bedside evaluations.

End-tidal carbon dioxide is associated with mortality and lactate in patients with suspected sepsis.

OBJECTIVE: Exhaled end-tidal carbon dioxide (ETCO(2)) concentration is associated with lactate levels in febrile patients. We assessed the association of ETCO(2) with mortality and lactate levels in patients with suspected sepsis. METHODS: This was a prospective observational study. We enrolled 201 adult patients presenting with suspected infection and 2 or more systemic inflammatory response syndrome criteria. Lactate and ETCO(2) were measured and analyzed with patient outcomes. RESULTS: The area under the receiver operator characteristics curve (AUC) was 0.75 (confidence interval [CI], 0.65-0.86) for lactate and mortality and 0.73 (CI, 0.61-0.84) for ETCO(2) and mortality. When analyzed across the different categories of sepsis, the AUCs for lactate and mortality were 0.61 (CI, 0.36-0.87) for sepsis, 0.69 (CI, 0.48-0.89) for severe sepsis, and 0.74 (CI, 0.55-0.93) for septic shock. The AUCs for ETCO(2) and mortality were 0.60 (CI, 0.37-0.83) for sepsis, 0.67 (CI, 0.46-0.88) for severe sepsis, and 0.78 (CI, 0.59-0.96) for septic shock. There was a significant inverse relationship between ETCO(2) and lactate in all categories, with correlation coefficients of -0.421 (P < .001) in the sepsis group, -0.597 (P < .001) in the severe sepsis group, and -0.482 (P = .011), respectively. Adjusted odds ratios were calculated, demonstrating 3 significant predictors of mortality: use of vasopressors 16.4 (95% CI, 1.80-149.2), mechanical ventilation 16.4 (95% CI, 3.13-85.9), and abnormal ETCO(2) levels 6.48 (95% CI, 1.06-39.54). CONCLUSIONS: We observed a significant association between ETCO(2) concentration and in-hospital mortality in emergency department patients with suspected sepsis across a range of disease severity.

Serum levels of ubiquitin C-terminal hydrolase distinguish mild traumatic brain injury from trauma controls and are elevated in mild and moderate traumatic brain injury patients with intracranial lesions and neurosurgical intervention.

BACKGROUND: This study compared early serum levels of ubiquitin C-terminal hydrolase (UCH-L1) from patients with mild and moderate traumatic brain injury (TBI) with uninjured and injured controls and examined their association with traumatic intracranial lesions on computed tomography (CT) scan (CT positive) and the need for neurosurgical intervention (NSI). METHODS: This prospective cohort study enrolled adult patients presenting to three tertiary care Level I trauma centers after blunt head trauma with loss of consciousness, amnesia, or disorientation and a Glasgow Coma Scale (GCS) score 9 to 15. Control groups included normal uninjured controls and nonhead injured trauma controls presenting to the emergency department with orthopedic injuries or motor vehicle crash without TBI. Blood samples were obtained in all trauma patients within 4 hours of injury and measured by enzyme-linked immunosorbent assay for UCH-L1 (ng/mL ± standard error of the mean). RESULTS: There were 295 patients enrolled, 96 TBI patients (86 with GCS score 13-15 and 10 with GCS score 9-12), and 199 controls (176 uninjured, 16 motor vehicle crash controls, and 7 orthopedic controls). The AUC for distinguishing TBI from uninjured controls was 0.87 (95% confidence interval [CI], 0.82-0.92) and for distinguishing those TBIs with GCS score 15 from controls was AUC 0.87 (95% CI, 0.81-0.93). Mean UCH-L1 levels in patients with CT negative versus CT positive were 0.620 (± 0.254) and 1.618 (± 0.474), respectively (p < 0.001), and the AUC was 0.73 (95% CI, 0.62-0.84). For patients without and with NSI, levels were 0.627 (0.218) versus 2.568 (0.854; p < 0.001), and the AUC was 0.85 (95% CI, 0.76-0.94). CONCLUSION: UCH-L1 is detectable in serum within an hour of injury and is associated with measures of injury severity including the GCS score, CT lesions, and NSI. Further study is required to validate these findings before clinical application. LEVEL OF EVIDENCE: II, prognostic study.

A comparison of tele-education versus conventional lectures in wound care knowledge and skill acquisition.

We conducted a randomized controlled study to compare conventional lectures with tele-education for delivering wound care education. Education was delivered by the two methods simultaneously to two classes. Forty-eight paramedics received a live didactic presentation and 41 paramedics received the same lecture via videoconferencing. The participants were evaluated by a multiple-choice examination and a practical test of their wound closure skills. There were no significant differences in any category of the practical skills test, and no difference in the results of the written examination: the mean total score was was 109.0 (95% CI 105.7-112.4) in the conventional lecture group and 110.3 (95% CI 106.2-114.3) in the video group (P = 0.63). In a survey at the end of the study the live lecture group rated the overall effectiveness of teaching significantly higher than the video-based group: the median scores for effectiveness of teaching were 6.0 (IQR 5.5-6.0) in the live lecture group and 4.0 (IQR 3.0-5.0) in the video group (P < 0.001). Videoconferencing was at least as effective as live didactic presentation.