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Background: Emergency medical services (EMS) personnel commonly encounter sepsis, yet little is known about their understanding of sepsis.Study Objectives: To determine the awareness, knowledge, current practice, and attitudes about sepsis among EMS personnel.Methods: We performed an anonymous, multi-agency, online survey of emergency medical technicians (EMTs), firefighter-emergency medical technicians (FF-EMTs), and paramedics in a metropolitan, 2-tier EMS system. We compared responses according to the level of EMS training and used multivariable logistic regression to determine the odds of correctly identifying the definition of sepsis, independent of demographic and professional factors.Results: Overall response rate of study participants was 57% (786/1390), and was greatest among EMTs (79%; 276/350). A total of 761 respondents (97%) had heard of the term "sepsis." EMTs and FF-EMTs were at significantly reduced odds of correctly defining sepsis compared to paramedics, independent of age, sex, and years of experience (EMTs: odds ratio 0.44, 95% confidence interval 0.3-0.8; FF-EMTs: odds ratio 0.32, 95% confidence interval 0.2-0.6. Overall, knowledge of the clinical signs and symptoms and recommended treatments for sepsis was typically>75%, though better among paramedics than EMTs or FF-EMTs (p<0.01). The majority of respondents believed sepsis is not recognized by EMS "some" or "a lot" of the time (76%, 596/786).Conclusions: EMS personnel demonstrated an overall sound awareness of sepsis. Knowledge of sepsis was less among FF-EMTs and EMTs compared to paramedics. These results suggest that paramedics could be integrated into strategies of early identification and treatment of sepsis, and EMTs may benefit from focused education and training. [ABSTRACT FROM AUTHOR]

Background: Randomized trials of prehospital cooling after cardiac arrest have shown that neither prehospital cooling nor targeted temperature management differentially affected short-term survival or neurological function. In this follow-up study, we assess the association of prehospital hypothermia with neurological function at least 3 months after cardiac arrest and survival 1 year after cardiac arrest., Methods and Results: There were 508 individuals who were discharged alive from hospitals in King County, Washington; 373 (73%) were interviewed by telephone 123±43 days after the initial event. Overall, 59% of the treatment group and 58% of the control group had Cerebral Performance Category (CPC) 1 or 2 (P=0.70), and 50% of the treatment group and 49% of the control group had slight disability or better by the Modified Rankin Scale (MRS; (P=0.35). One-year survival was 87% in the treatment group and 84% in the control group (P=0.42). Of those with CPC 1 at hospital discharge, 68% had CPC 1 or 2 at follow-up, and 59% had MRS of slight disability or better. Of 41 patients with CPC 3 or 4 at discharge, only 12% had CPC 2 at follow-up, and just 5% had MRS of slight disability or better. One-year survival was 92% for CPC 1 at discharge, but only 40% for CPC 4., Conclusion: In addition to excellent survival, patients who had good neurological function at discharge continued to have good function at least 3 months after the event., Clinical Trial Registration: URL: Clinicaltrials.gov. Unique identifier: NCT00391469., (© 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Importance: Hospital cooling improves outcome after cardiac arrest, but prehospital cooling immediately after return of spontaneous circulation may result in better outcomes., Objective: To determine whether prehospital cooling improves outcomes after resuscitation from cardiac arrest in patients with ventricular fibrillation (VF) and without VF., Design, Setting, and Participants: A randomized clinical trial that assigned adults with prehospital cardiac arrest to standard care with or without prehospital cooling, accomplished by infusing up to 2 L of 4°C normal saline as soon as possible following return of spontaneous circulation. Adults in King County, Washington, with prehospital cardiac arrest and resuscitated by paramedics were eligible and 1359 patients (583 with VF and 776 without VF) were randomized between December 15, 2007, and December 7, 2012. Patient follow-up was completed by May 1, 2013. Nearly all of the patients resuscitated from VF and admitted to the hospital received hospital cooling regardless of their randomization., Main Outcomes and Measures: The primary outcomes were survival to hospital discharge and neurological status at discharge., Results: The intervention decreased mean core temperature by 1.20°C (95% CI, -1.33°C to -1.07°C) in patients with VF and by 1.30°C (95% CI, -1.40°C to -1.20°C) in patients without VF by hospital arrival and reduced the time to achieve a temperature of less than 34°C by about 1 hour compared with the control group. However, survival to hospital discharge was similar among the intervention and control groups among patients with VF (62.7% [95% CI, 57.0%-68.0%] vs 64.3% [95% CI, 58.6%-69.5%], respectively; P = .69) and among patients without VF (19.2% [95% CI, 15.6%-23.4%] vs 16.3% [95% CI, 12.9%-20.4%], respectively; P = .30). The intervention was also not associated with improved neurological status of full recovery or mild impairment at discharge for either patients with VF (57.5% [95% CI, 51.8%-63.1%] of cases had full recovery or mild impairment vs 61.9% [95% CI, 56.2%-67.2%] of controls; P = .69) or those without VF (14.4% [95% CI, 11.3%-18.2%] of cases vs 13.4% [95% CI,10.4%-17.2%] of controls; P = .30). Overall, the intervention group experienced rearrest in the field more than the control group (26% [95% CI, 22%-29%] vs 21% [95% CI, 18%-24%], respectively; P = .008), as well as increased diuretic use and pulmonary edema on first chest x-ray, which resolved within 24 hours after admission., Conclusion and Relevance: Although use of prehospital cooling reduced core temperature by hospital arrival and reduced the time to reach a temperature of 34°C, it did not improve survival or neurological status among patients resuscitated from prehospital VF or those without VF., Trial Registration: clinicaltrials.gov Identifier: NCT00391469.

Objectives: Emergency medical services (EMS) personnel commonly use systolic blood pressure (sBP) to triage and treat acutely ill patients. The definition of prehospital hypotension and its associated outcomes are poorly defined. The authors sought to determine the discrimination of prehospital sBP thresholds for 30-day mortality and to compare patient classification by best-performing thresholds to traditional cutoffs., Methods: In a community-based cohort of adult, nontrauma, noncardiac arrest patients transported by EMS between 2002 and 2006, entries to state hospital discharge data and death certificates were linked. Prehospital sBP thresholds between 40 and 140 mm Hg in derivation (n = 132,624) and validation (n = 22,020) cohorts and their discrimination for 30-day mortality, were examined. Cutoffs were evaluated using the 0/1 distance, Youden index, and adjusted Z-statistics from multivariable logistic regression models., Results: In the derivation cohort, 1,594 (1.2%) died within 24 hours, 7,404 (6%) were critically ill during hospitalization, and 6,888 (5%) died within 30 days. The area under the receiver operating characteristic (ROC) curve for sBP was 0.60 (95% confidence interval [CI] = 0.59, 0.61) for 30-day mortality and 0.64 (95% CI = 0.62 0.66) for 24-hour mortality. The 0/1 distance, Youden index, and adjusted Z-statistics found best-performing sBP thresholds between 110 and 120 mm Hg. When compared to an sBP ≤ 90 mm Hg, a cutoff of 110 mm Hg would identify 17% (n = 137) more deaths at 30 days, while overtriaging four times as many survivors., Conclusions: Prehospital sBP is a modest discriminator of clinical outcomes, yet no threshold avoids substantial misclassification of 30-day mortality among noninjured patients., (© 2013 by the Society for Academic Emergency Medicine.)

Despite reports of patients with resuscitated sudden cardiac arrest (rSCA) receiving acute cardiac catheterization, the efficacy of this strategy is largely unknown. We hypothesized that acute cardiac catheterization of patients with rSCA would improve survival to hospital discharge. A retrospective cohort of 240 patients with out-of-hospital rSCA caused by ventricular tachycardia or fibrillation was identified from 11 institutions in Seattle, Washington from 1999 through 2002. Patients were grouped into those receiving acute catheterization within 6 hours (≤6-hour group, n = 61) and those with deferred catheterization at >6 hours or no catheterization during the index hospitalization (>6-hour group, n = 179). Attention was directed to survival to hospital discharge, neurologic status, extent of coronary artery disease, presenting electrocardiographic findings, and symptoms before arrest. Propensity-score methods were used to adjust for the likelihood of receiving acute catheterization. Survival was greater in patients who underwent acute catheterization (72% in the ≤6-hour group vs 49% in the >6-hour group, p = 0.001). Percutaneous coronary intervention was performed in 38 of 61 patients (62%) in the ≤6-hour group and 13 of 170 patients (7%) in the >6-hour group (p <0.0001). Neurologic status was similar in the 2 groups. A significantly larger percentage of patients in the acute catheterization group had symptoms before cardiac arrest and had ST-segment elevation on electrocardiogram after resuscitation. Age, bystander cardiopulmonary resuscitation, daytime presentation, history of percutaneous coronary intervention or stroke, and acute ST-segment elevation were positively associated with receiving cardiac catheterization. In conclusion, in this series of patients who sustained out-of-hospital cardiac arrest, acute catheterization (<6 hours of presentation) was associated with improved survival., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Nonphysician advanced life support (ALS) providers often perform tracheal intubation (TI) for cardiac arrest or other life-threatening indications in the prehospital setting, where airway assessment and airway management tools are limited. However, the frequency of difficult TI in obese patients in this setting is unclear. In this study we determined factors associated with TI success, and determined TI difficulty as a function of body mass index (BMI) in a system of ALS providers experienced in TI, to guide future prehospital education efforts., Methods: A retrospective review was performed of all patients ≥15 years of age who underwent prehospital TI by paramedics in the Seattle Medic One system over a 4-year period, and were transported to the regional level 1 trauma center (Harborview Medical Center). Data were abstracted from a prospectively collected prehospital airway management database and from the hospital medical records, including demographic information, number of TI attempts, TI success or failure, and body weight/height (BMI). Descriptive statistics and multivariable logistic regression were calculated, with the primary end point being difficult TI (defined as ≥4 TI attempts or the need to use an alternative airway management technique)., Results: Of 80,501 patient contacts in whom 4114 TIs were attempted during the 4-year study period, 823 met study entry criteria (including a calculable BMI). The overall TI success rate in the study population was 98.5% (811 out of 823), with 6.8% (56 out of 823) meeting the predetermined definition for difficult TI. There was no significant association between difficult TI and patient age, gender, use of succinylcholine, or medical diagnosis (trauma vs. nontrauma). In comparison with the lean patient subgroup (BMI <30 kg/m(2)), patients with class III obesity (BMI >40 kg/m(2)) had a significant association with difficult TI (odds ratio 3.68; confidence interval [CI] 1.27-10.59), whereas those with class I/II obesity (BMI ≥30 kg/m(2) and <40 kg/m(2)) did not (odds ratio 0.98; CI 0.46 -2.07)., Conclusions: Among prehospital ALS providers with previously documented and published successful TI performance, increased difficulty with TI was observed in patients with extreme obesity, but not in patients with lesser degrees of obesity. Because extreme obesity is an easily identifiable patient characteristic, didactic and clinical (e.g., operating room) airway management education for such providers should emphasize airway management challenges and strategies associated with obesity, including specific equipment, patient positioning, and practice recommendations that may facilitate both TI and alternative airway management techniques in this population., (© 2011 International Anesthesia Research Society)

The advent and incorporation of the air bag into motor vehicles has resulted in the mitigation of many head and truncal injuries in motor vehicle collisions. However, air bag deployment is not risk free. We present a case of sodium azide-induced laryngospasm after air bag deployment. An unrestrained male driver was in a moderate-speed motor vehicle collision with air bag deployment. Medics found him awake, gasping for air with stridorous respirations and guarding his neck. The patient had no external signs of trauma and was presumed to have tracheal injury. The patient was greeted by the Anesthesiology service, which intubated him using glidescope-assisted laryngoscopy. The patient was admitted for overnight observation and treatment of alkaline ocular injury and laryngospasm. Although air bags represent an important advance in automobile safety, their use is not without risk. Bruising and tracheal rupture secondary to air bag deployment have been reported in out-of-position occupants. Additionally, alkaline by-products from the combustion of sodium azide in air bags have been implicated in ocular injury and facial burns. Laryngospasm after sodium azide exposure presents another diagnostic challenge for providers. Therefore, it is incumbent to maintain vigilance in the physical examination and diagnosis of occult injuries after air bag deployment., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Little is known of the associations of endogenous fatty acids with sudden cardiac arrest (SCA). We investigated the associations of SCA with red blood cell membrane fatty acids that are end products of de novo fatty acid synthesis: myristic acid (14:0), palmitic acid (16:0), palmitoleic acid (16:1 n7), vaccenic acid (18:1 n7), stearic acid (18:0), oleic acid (18:1 n9), and a related fatty acid, cis-7 hexadecenoic acid (16:1 n9). We used data from a population-based case-control study where cases, aged 25 to 74 years, were out-of-hospital SCA patients attended by paramedics in Seattle, WA (n = 265). Controls, matched to cases by age, sex, and calendar year, were randomly identified from the community (n = 415). All participants were free of prior clinically diagnosed heart disease. We observed associations of higher red blood cell membrane levels of 16:0, 16:1n-7, 18:1n-7, and 16:1n-9 with higher risk of SCA. In analyses adjusted for traditional SCA risk factors and trans- and n-3 fatty acids, a 1-SD-higher level of 16:0 was associated with 38% higher risk of SCA (odds ratio, 1.38; 95% confidence interval, 1.12-1.70) and a 1-SD-higher level of 16:1n-9 with 88% higher risk (odds ratio, 1.88; 95% confidence interval, 1.27-2.78). Several fatty acids that are end products of fatty acid synthesis are associated with SCA risk. Further work is needed to investigate if conditions that favor de novo fatty acid synthesis, such as high-carbohydrate/low-fat diets, might also increase the risk of SCA.

Background: Emergency airway management is an important component of resuscitation of critically ill patients. Multiple studies demonstrate variable endotracheal intubation (ETI) success by prehospital providers. Data describing how many ETI training experiences are required to achieve high success rates are sparse., Objectives: To describe the relationship between the number of prehospital ETI experiences and the likelihood of success on subsequent ETI and to specifically look at uncomplicated first-pass ETI in a university-based training program with substantial resources., Methods: We conducted a secondary analysis of a prospectively collected cohort of paramedic student prehospital intubation attempts. Data collected on prehospital ETIs included indication, induction agents, number of direct laryngoscopy attempts, and advanced airway procedures performed. We used multivariable generalized estimating equations (GEE) analysis to determine the effect of cumulative ETI experience on first-pass and overall ETI success rates., Results: Over a period of three years, 56 paramedic students attempted 576 prehospital ETIs. The odds of overall ETI success were associated with cumulative ETI experience (odds ratio [OR] 1.097 per encounter, 95% confidence interval [CI] = 1.026-1.173, p = 0.006). The odds of first-pass ETI success were associated with cumulative ETI experience (OR 1.061 per encounter, 95% CI = 1.014-1.109, p = 0.009)., Conclusion: In a training program with substantial clinical opportunities and resources, increased ETI success rates were associated with increasing clinical exposure. However, first-pass placement of the ETT with a high success rate requires high numbers of ETI training experiences that may exceed the number available in many training programs.

Objective: To evaluate whether implementation of a therapeutic hypothermia protocol on arrival in a community hospital improved survival and neurologic outcomes in patients initially found to have ventricular fibrillation, pulseless electrical activity, or asystole, and then successfully resuscitated from out-of-hospital cardiac arrest., Design: A retrospective study of patients who presented after implementation of a therapeutic hypothermia protocol compared with those who presented before the protocol was implemented., Setting: Harborview Medical Center, Seattle, WA., Patients: A total of 491 consecutive adults with out-of-hospital, nontraumatic cardiac arrest who presented between January 1, 2000 and December 31, 2004., Interventions: An active cooling therapeutic hypothermia protocol, using ice packs, cooling blankets, or cooling pads to achieve a temperature of 32 degrees C to 34 degrees C was initiated on November 18, 2002 for unconscious patients resuscitated from cardiac arrest., Measurements and Main Results: Demographics and outcomes were obtained from medical records and an emergency medical database. The primary outcomes were survival and favorable neurologic outcome at discharge associated with the therapeutic hypothermia protocol. An adjusted analysis was performed, using a multivariate regression. During the therapeutic hypothermia period, 204 patients were brought to the emergency department; of these 204 patients, 132 (65%) ultimately achieved temperatures of <34 degrees C. Of the 72 patients who did not achieve goal temperatures: 40 (20%) died in the emergency department or shortly after being admitted to the hospital, 15 (7%) regained consciousness, four (2%) had contraindications, 13 (6%) had temperature increase or did not have documented use of the therapeutic hypothermia protocol. In the prior period, none of the 287 patients received active cooling. Patients admitted in the therapeutic hypothermia period had a mean esophageal temperature of 34.1 degrees C during the first 12 hrs compared with 35.2 degrees C in the pretherapeutic hypothermia period (p < .01). Survival to hospital discharge improved in the therapeutic hypothermia period in patients with an initial rhythm of ventricular fibrillation (odds ratio, 1.88, 95% confidence interval, 1.03-3.45), however not in patients with nonventricular fibrillation (odds ratio, 1.17, 95% confidence interval, 0.66-2.05). In adjusted analysis, ventricular fibrillation patients during the therapeutic hypothermia period trended toward improved survival (odds ratio, 1.71, 95% confidence interval, 0.85-3.46) and had favorable neurologic outcome (odds ratio, 2.62, 95% confidence interval, 1.1-6.27) compared with the earlier period. This benefit was not observed in patients whose initial rhythm was pulseless electrical activity or asystole., Conclusions: The therapeutic hypothermia period was associated with a significant improvement in neurologic outcomes in patients whose initial rhythm was ventricular fibrillation, but not in patients with other rhythms.

The role of prehospital endotracheal intubation (ETI) remains controversial, with significant national variability in practice. The purpose of this project was to evaluate ETI management in a system of advanced life support (ALS) providers experienced in ETI and other advanced airway techniques, and describe management and outcomes of patients with a "difficult airway." Data were collected prospectively for all ETIs performed by the fire department over a 4-year period (2001-2005), and included demographics, number of laryngoscopy attempts, airway procedures, complications, and outcomes. Of 80,501 ALS patient contacts, 4091 (5.1%) underwent attempted oral ETI, with a 96.8% success rate in four or fewer attempts. The difficult airway cohort included 130 patients (3.2%), whose airway management consisted of oral ETI after more than four attempts (46%), bag-valve-mask ventilation (33%), cricothyroidotomy (8%), retrograde ETI (5%), and digital ETI (1%). Procedural success rates ranged from 14% (digital ETI) to 91% (cricothyroidotomy). Nine patients (7%) had failed airway management, of whom 5 were found in cardiac arrest. The two most common reasons subjectively reported by ALS providers for airway difficulty were anterior trachea (39%) and small mouth (30%). Overall mortality for the difficult airway cohort was 44%. Prehospital ETI can be performed with a high success rate by experienced ALS providers, but may still require advanced airway techniques in a small subset of patients. Patient anatomy is a primary factor in failed ETI. Among the advanced procedures, cricothyroidotomy had the highest success rate and should not be delayed by other interventions.

Higher levels of long-chain n-3 polyunsaturated fatty acids in red blood cell membranes are associated with lower risk of sudden cardiac arrest. Whether membrane levels of alpha-linolenic acid, a medium-chain n-3 polyunsaturated fatty acid, show a similar association is unclear. We investigated the association of red blood cell membrane alpha-linolenic acid with sudden cardiac arrest risk in a population-based case-control study. Cases, aged 25 to 74 years, were out-of-hospital sudden cardiac arrest patients attended by paramedics in Seattle, WA (n = 265). Controls, matched to cases by age, sex, and calendar year, were randomly identified from the community (n = 415). All participants were free of prior clinically diagnosed heart disease. Blood was obtained at the time of cardiac arrest (cases) or at the time of an interview (controls). Higher membrane alpha-linolenic acid was associated with a higher risk of sudden cardiac arrest: after adjustment for matching factors and smoking, diabetes, hypertension, education, physical activity, weight, height, and total fat intake, the odds ratios corresponding to increasing quartiles of alpha-linolenic acid were 1.7 (95% confidence interval [CI], 1.0-3.0), 1.9 (95% CI, 1.1-3.3), and 2.5 (95% CI, 1.3-4.8) compared with the lowest quartile. The association was independent of red blood cell levels of long-chain n-3 fatty acids, trans-fatty acids, and linoleic acid. Higher membrane levels of alpha-linolenic acid are associated with higher risk of sudden cardiac arrest.

Hypothermia has emerged as a potent neuroprotective modality following resuscitation from cardiac arrest. Although delayed hospital cooling has been demonstrated to improve outcome after cardiac arrest, in-field cooling begun immediately following the return of spontaneous circulation may be more beneficial. Cooling in the field following resuscitation, however, presents new challenges, in that the cooling method has to be portable, safe, and effective. Rapid infusion of intravenous fluid at 4 degrees C, the use of a cooling helmet, and cooling plates have all been proposed as methods for field cooling, and are all in various stages of clinical and animal testing. Whether field cooling will improve survival and neurologic outcome remains an important unanswered clinical question.

Cardiopulmonary arrest and trauma are two of the major epidemics of our time. In most cases, the final outcome is altered, for better or for worse, by how interventions are provided in the prehospital setting, making that venue critical for lifesaving community research efforts. In certain venues, out-of-hospital emergency medical services personnel are highly skilled at managing resuscitations and routinely operate under strict, highly scrutinized protocols, resulting in extraordinary study compliance. Larger patient enrollment derived from population-based investigations can lead to faster study completion, less selection bias, higher-powered data, and enhanced subgroup analysis. Most importantly, the concomitant training, expert protocol development, and rigid scrutiny all lead to improved patient outcomes, regardless of study intervention. For successful implementation, emergency medical services personnel should be involved in study design, and utilize routine, automated data collection. Technologies should be provided that simplify tasks and diminish confounding variables. Considering that exception to informed consent is a critical component, prospective education and involvement of the medical community, community leaders, employee groups and the media, long before protocol implementation, is essential. Such efforts should be led by respected, academically authoritative, grassroots emergency medical services medical directors and trauma chiefs, preferably those based at the main trauma centers or public receiving facilities.

Objective: The use of prehospital needle thoracostomy (NT) is controversial as it is not without risk. Issues such as inappropriate patient selection, misplacement causing iatrogenic injury, treatment failures in obese patients, and delaying definitive tube thoracostomy in the emergency department contribute to this controversy. The purpose of this study is to evaluate a cohort of patients undergoing NT by paramedics for tension pneumothorax and review the indications for use, complications, and emergency department outcomes of NT., Methods: We conducted a retrospective review of patients undergoing NT in the prehospital setting and transported directly to a Level 1 trauma center over a one-year period. Patients were transported by a single ground transport agency staffed by paramedics. All paramedics were trained to follow uniform protocols for treatment procedures. Variables included indications for NT, patient demographics, prehospital vital signs, injury mechanism, chest X-ray, and Emergency Department outcomes., Results: Paramedics responded to 20,330 advanced life support calls, and 39 (0.2%) patients had a NT placed for treatment of tension pneumothorax. Twenty-two (56.4%) patients were in circulatory arrest, with 12 suffering traumatic arrest and 10 patients in nontraumatic PEA arrest. The remaining 17 (43.6%) patients were treated for nonarrest causes., Conclusions: The use of NT appears to be a safe procedure when preformed by paramedics in an urban EMS system. Prehospital NT resulted in four cases of unexpected survival.

Cardiac arrest is the leading cause of death among dialysis patients in the United States. We measured the outcome of cardiac arrests attended by Emergency Medical Services (EMS) staff at hemodialysis facilities in a 14-year population-based retrospective study to identify cardiac arrest cases at a dialysis unit. Associated factors were determined using unconditional logistic regression. Of the 102 cardiac arrests identified around the time of dialysis, 10 occurred before, 72 during, and 20 after hemodialysis. The initial measured abnormality was ventricular fibrillation or tachycardia in 72 cases. Of those who survived transportation to a hospital, survival to discharge was 24 with 15% survival at 1 year. Compared to arrests that occurred prior to dialysis, the odds of ventricular fibrillation were 5-fold greater in patients on dialysis but 14-fold greater in those arresting after dialysis. One-third of cases occurred after the introduction of automated external defibrillators, and in half of the cases these devices were attached prior to EMS arrival. Once these devices were attached, most were used for defibrillation. We conclude that ventricular arrhythmias are the predominant features among arrested in-center dialysis patients with most occurrences during dialysis. The role of these devices in dialysis units will need a larger study to evaluate their efficacy.

Background: Recently, we have demonstrated that patients with traumatic brain injury (TBI) with an arrival PaCo2 30 to 35 mm Hg have improved outcome compared with those outside this target range. We sought to determine whether achieving ventilation into a target range would translate into better outcomes in patients with TBI., Methods: Data were retrospectively reviewed for all trauma prehospital intubations during a period of 24 months (n = 851). Targeted ventilation was defined as a PaCo2 between 30 and 39 mm Hg. Arterial blood gases collected within 15 minutes of patient arrival were assessed and compared with subsequent arterial blood gases to determine patient's ventilation status over time., Results: There was no difference in patient demographics between various ventilation groups. Patients with TBI who achieved the target range had a mortality of 21.2% compared with 33.7% for those who persistently remained outside this range (p = 0.03). Logistic regression demonstrated a trend toward lower mortality for those TBI patients who achieved the target range while in the emergency department (odds ratio 0.33, 95% confidence interval 0.15-0.75)., Conclusion: Optimal outcome is achieved when the patient is in the target ventilation range on arrival and remains within it. Ventilation status in trauma patients should be closely monitored after intubation to develop an optimal ventilation strategy for patients with severe TBI.

Background: The leading cause of late mortality after trauma is multiple organ failure syndrome, due to a dysfunctional inflammatory response early after injury. Preclinical studies demonstrate that hypertonicity alters the activation of inflammatory cells, leading to reduction in organ injury. The purpose of this study was to evaluate the effect of hypertonicity on organ injury after blunt trauma., Design: Double-blind, randomized controlled trial from October 1, 2003, to August 31, 2005., Setting: Prehospital enrollment at a single level I trauma center., Patients: Patients older than 17 years with blunt trauma and prehospital hypotension (systolic blood pressure,

Background: Prehospital intubation has been challenged on the grounds that it predisposes to hyperventilation, which is detrimental after traumatic brain injury (TBI), and impairs venous return in patients with hypovolemia. We sought to determine the incidence of hyperventilation among a cohort of trauma patients undergoing prehospital intubation and the impact of ventilation on outcome after severe TBI., Methods: Data were prospectively collected for all intubated trauma patients transported directly from the field for a period of 14 months (n = 574). An arrival Pco2 <30 mm Hg was termed severe hypocapnea and considered a marker of hyperventilation. Patients with a Pco2 >45 mm Hg were considered severely hypercapneic. Targeted ventilation was defined as a Pco2 between 30 and 35 mm Hg based on the Brain Trauma Foundation guidelines., Results: The rate of severe hypocapnea was 18% and women were more likely to be hyperventilated (p < 0.05). Patients with severe hypercapnia had higher Injury Severity Scores and were more likely hypotensive, hypoxic, and acidodic (p < 0.05). Patients in the targeted ventilation range were less likely to die than were those outside the range even after excluding the severe hypercapnea group (odds ratio, 0.57; 95% confidence interval, 0.33-0.99). This effect was even greater among patients with isolated TBI (odds ratio, 0.31; 95% confidence interval, 0.10-0.96)., Conclusion: Targeted prehospital ventilation is associated with lower mortality after severe TBI.

Dendritic cells (DC) are of central importance in the initiation of T cell-mediated adaptive immunity because these professional phagocytes internalize, process, and present microbial antigens to T lymphocytes. T lymphocytes have a pivotal role in controlling and clearing infection with intracellular pathogens through cytokine production. T lymphocytes also can mediate direct lysis of infected cells or activate B and T cells. In this article, we report that DC, when cocultured with Salmonella, fail to efficiently stimulate T cells for proliferation. We show that the failure of T lymphocytes to respond to Salmonella-infected DC is not simply due to Salmonella-induced programmed DC death or interference with up-regulation of costimulatory molecules CD80 and CD86. We cocultured bacteria with purified T lymphocytes, and we demonstrate here that Salmonella have a direct, contact-dependent inhibitory effect on the T cells, even in the absence of DC. This direct, Salmonella-induced inhibitory effect reduces the ability of T cells to proliferate and produce cytokines in response to stimulation and appears to require live bacteria. Cumulatively, these results are evidence that Salmonella may interfere with the development of acquired immunity, providing insights into the complex nature of this host-pathogen interaction.

Study Objective: Maximizing cardiopulmonary resuscitation (CPR) during resuscitation may improve survival. Resuscitation protocols stack up to 3 shocks to achieve defibrillation, followed by an immediate postdefibrillation pulse check. The purpose of this study is to evaluate outcomes of rhythm reanalyses immediately after shock, stacked shocks, and initial postshock pulse checks in relation to achieving a pulse and initiating CPR., Methods: We conducted an observational study of patients with ventricular fibrillation treated by first-tier emergency medical services (EMS). We collected data from EMS, dispatch, and hospital records. Additionally, we analyzed automatic external defibrillator recordings to determine the proportion of cardiac arrest victims who were defibrillated and achieved a pulse according to shock number (single versus stacked shock), proportion of victims with a pulse during the initial postdefibrillation pulse check, and interval from initial shock to CPR., Results: The study included 481 cardiac arrest subjects. Automatic external defibrillators terminated ventricular fibrillation with the initial shock in 83.6% (n=402) of cases. A second shock terminated ventricular fibrillation in an additional 7.5% (n=36) of cases, and a third shock terminated ventricular fibrillation in 4.8% (n=23) of cases. The initial sequence of 3 shocks failed to terminate ventricular fibrillation in 4.1% (n=20) of cases. In total, automatic external defibrillators performed 560 rhythm reanalyses during the initial shock sequence and delivered 122 "stacked" shocks. Termination of ventricular fibrillation was not synonymous with return of a pulse. The initial shock produced a pulse that was eventually detected in 21.8% (105/481) of cases. Stacked shocks produced a pulse in 10.7% (13/122) of cases. For the 24.5 % (n=118) of cases in which a pulse returned, the pulse was detected during the initial postshock pulse check only 12 times, or 2.5% of all cases. The median interval from initial shock until CPR was 29 (23,41) seconds., Conclusion: Rhythm reanalyses, stacked shocks, and postshock pulse checks had low yield for achieving or detecting return of a pulse. CPR was not initiated until 29 seconds after the initial shock.

Background: Several studies have demonstrated that the success rate of prehospital intubation is improved by the use of neuromuscular blocking agents (NMBAs). However, a recent study has reported that prehospital intubation with NMBAs worsens outcome after traumatic brain injury (TBI). We sought to determine the effect of the use of NMBAs to facilitate prehospital intubation on outcome after TBI., Methods: All patients admitted to our Level I trauma center with a head Abbreviated Injury Scale score >/= 3 were identified by the trauma registry (January 1998-June 2003). Patient records were matched with prehospital databases. Patients were further stratified on the basis of prehospital Glasgow Coma Scale (GCS) score into mild (GCS score of 14/15), moderate (GCS score of 9-13), and severe (GCS score < 9) TBI. Outcome included mortality and good outcome (survival to discharge with a GCS score of 14/15)., Results: There were 3,052 patients who were identified as having been transported directly from the field. Complete prehospital data were available for 2,012 patients (66%). Of these, 920 were mild TBI (intubation rate, 17.4%), 293 moderate TBI (intubation rate, 57.7%), and 799 severe TBI (intubation rate, 95%). Overall, 72% of intubated patients received NMBAs. There were no significant differences in demographics or injury severity between the groups. Patients not receiving NMBAs were more likely to be hypotensive and have prehospital cardiopulmonary resuscitation (p = 0.001). The unadjusted mortality for the patients intubated with NMBAs was 25% versus 37% for those not receiving NMBAs (p < 0.001). When adjusted for confounding variables, patients intubated with NMBAs were more likely to survive (odds ratio, 0.63; 95% confidence interval, 0.41-0.97; p = 0.04) and have a good outcome (odds ratio, 1.7; 95% confidence interval, 1.2-2.6; p = 0.006) than those in the no-NMBA group., Conclusion: The use of NMBAs to facilitate prehospital intubation improves outcome for patients with TBI. The value of prehospital intubation for TBI remains to be determined; however, any trial evaluating nonintubation for TBI must be compared with NMBA-facilitated intubation to be valid.

Genetic factors may influence outcome from cardiac arrest. In Seattle, WA, paramedics collected blood specimens from patients who had suffered cardiac arrest outside of a medical institution (out of hospital cardiac arrest). We examined associations between apolipoprotein E (APOE) genotype and outcome in 134 who died "in the field", 131 who died in the hospital, 198 patients who were discharged from hospital alive, and 64 control subjects. APOE genotype was not significantly related to outcome, including being alive at and being independent by 3 months after the arrest. Specifically, having one or two alleles of APOE epsilon4 or having APOE epsilon3/epsilon3 was not related to outcome, even after controlling for age, sex, race, and initial rhythm. We failed to confirm previous studies and found no significant associations between APOE genotype and outcome from out of hospital cardiac arrest.

Objectives: Our objectives are to describe details of the dispatcher assisted cardiopulmonary resuscitation (CPR) instruction program we implemented during a 12 years study and to provide estimates of the potential number of out-of-hospital cardiac arrests that might benefit from such instruction based on data from the last 77 months., Methods: Basic data were obtained for all episodes of out-of-hospital cardiac arrest in the city of Seattle, as well as all emergency medical services (EMS) dispatches for suspected cardiac arrest. In addition to EMS run reports, data sources included audio tapes of dispatches, and interviews of callers. These data were used in a potential benefit analysis., Results: Over a period of 77 months, 54% (3320/6130) of cardiac arrests received advanced cardiac life support (ACLS) by Seattle Fire Department emergency medical technicians (EMTs) and paramedics. We estimated that 29.9% (994/3320) of cardiac arrests in Seattle treated by EMS could have theoretically benefited from dispatcher assisted CPR. No serious adverse consequences of a dispatcher assisted CPR program were observed. Failure to identify a cardiac arrest by dispatchers was largely attributed to deviation from a well-defined protocol. However, non-arrests identified, initially as arrests appeared to be unavoidable., Conclusions: In the city of Seattle, some 29.9% of all out-of-hospital cardiac arrest victims who received ACLS had the potential to benefit from dispatcher assisted CPR.

Study Objectives: Little is known regarding the potential effects of emergency medical services (EMS) on total heart disease mortality. Although EMS may provide health benefits in less acute cardiac conditions, its immediate, measurable, and direct effect on heart disease mortality is through resuscitation of persons suffering out-of-hospital cardiac arrest. The purpose of this study was to examine the involvement and potential mortality benefit of out-of-hospital EMS care of cardiac arrest on community heart disease mortality., Methods: The investigation was an observational study of all persons with death events resulting from heart disease as defined by heart disease deaths and deaths averted (persons successfully resuscitated from out-of-hospital cardiac arrest by EMS) in a single county from January 1, 2000, through December 31, 2000. The county of study has a population of nearly 2 million people and is composed of urban, suburban, and rural components. State vital records and EMS reports were used to ascertain deaths resulting from heart disease and deaths averted., Results: In the year 2000, 3,577 persons died as a result of heart disease, and 128 persons were successfully resuscitated and discharged from the hospital, for a total of 3,705 death events. EMS responded to 39% (1,428/3,705) of all heart disease death events and 57% (1,428/2,516) of out-of-hospital events, resulting in a 3.5% (128/3,705) reduction in overall heart disease mortality and a 5.1% (128/2,516) reduction in out-of-hospital mortality., Conclusion: EMS was involved in the majority of out-of-hospital heart disease death events, resulting in a measurable reduction in heart disease mortality.

Context: Recent reports from 2 European cities and an earlier observation from Seattle, Wash, suggest that the number of patients treated for out-of-hospital ventricular fibrillation (VF) has declined., Objective: To analyze the incidence of cardiac arrest and to examine relationships among incidence, sex, race, age, and first identified cardiac rhythm in Seattle., Design, Setting, and Patients: Population-based study of all cardiac arrest cases with presumed cardiac etiology who received advanced life support from Seattle Fire Department emergency medical services during specified periods between 1979 and 2000. United States Census data for Seattle in 1980, 1990, and 2000 were used to determine incidence rates for treated cardiac arrest with adjustments for age and sex., Main Outcome Measures: Changes in incidence of cardiac arrest and initial recorded cardiac rhythm., Results: The adjusted annual incidence of cardiac arrest with VF as the first identified rhythm decreased by about 56% from 1980 to 2000 (from 0.85 to 0.38 per 1000; relative risk [RR], 0.44; 95% confidence interval [CI], 0.37-0.53). Similar reductions occurred in blacks (54%; RR, 0.45; 95% CI, 0.26-0.79) and whites (53%; RR, 0.47; 95% CI, 0.38-0.58) and was most evident in men (57%; RR, 0.43; 95% CI, 0.35-0.53), in whom the baseline incidence was relatively high. When all treated arrests with presumed cardiac etiology were considered, that incidence decreased by 43% (RR, 0.58; 95% CI, 0.49-0.67) in men but negligibly in women, for whom a relatively low incidence of VF also declined but was offset by more cases with asystole or pulseless electrical activity., Conclusion: We observed a major decline in the incidence of out-of-hospital VF and in all cases of treated cardiac arrest presumably due to heart disease in Seattle. These changes likely reflect the national decline in coronary heart disease mortality.

Objective: To determine whether a brief session of behavior change counseling (BCC), offered to injured adolescents in the emergency department (ED) as a therapeutic intervention, could be used to change injury-related risk behaviors and the risk of reinjury., Study Design: A randomized, controlled trial., Participants: Adolescents between 12 and 20 years old who were undergoing treatment for an injury in the ED and who were cognitively able to participate in the intervention., Setting: An urban ED at a level 1 pediatric trauma center., Intervention: Study participants completed a baseline risk behavior prevalence assessment. Participants were then randomly assigned to receive BCC or routine ED care. Those in the treatment group underwent a brief session of BCC with a study social worker focused on changing an identified injury-related risk behavior (seatbelt use, bicycle helmet use, driving after drinking, riding with an impaired driver, binge drinking, or carrying a weapon). Participants were recontacted 3 months and 6 months after enrollment to assess the prevalence of positive behavior change and the interim occurrence of medically treated injuries., Results: We enrolled 631 participants (78% of those eligible) and obtained follow-up for 76% at 3 months and 75% at 6 months. The relative risk of a positive behavior change with respect to seatbelt use was 1.34 (95% confidence interval [CI]: 1.00, 1.79) at 3 months, favoring the intervention group. The relative risk for the same outcome was 1.47 (95% CI: 1.09, 1.96) at 6 months. A positive change in bicycle helmet use was 1.81 (95% CI: 1.02, 3.18) times more likely at 3 months and 2.00 (95% CI: 1.00, 4.00) times more likely at 6 months in the intervention group. There was no effect of the intervention on changes in other target behaviors. Over the 6-month follow-up period, the risk of reinjury requiring medical attention did not differ between treatment groups., Conclusions: Brief BCC can be delivered to adolescents undergoing treatment for injury in the ED and can be used to address injury-related risk behaviors. The intervention was associated with a greater likelihood of positive behavior change in seatbelt and bicycle helmet use. This effect lasted over 6 months of follow-up. BCC was not associated with changes in other risk behaviors and could not be shown to significantly reduce the risk of reinjury.

Considerable controversy persists regarding the optimal means and indications for airway management, the utility of paralytic agents to facilitate intubation, and the indications for advanced airway access techniques in the prehospital setting. To describe the use of intubation and advanced airway management in a system with extensive experience with both the use of paralytic agents and surgical airway techniques, a retrospective review was conducted of all prehospital airway procedures from January 1997 through November 1999. Data collected included demographics, airway management techniques, use of paralytic agents, and immediate outcome. The results showed there were 2700 patients intubated out of 50,118 patient encounters (5.4%). The indications for intubation included medical emergency in 82% of patients and traumatic injury in 18%. Fifty percent of patients were intubated with the use of succinylcholine. The overall oral intubation success rate was 98.4% and definitive airway access was achieved in all but 12 patients (0.6%), with 30 patients receiving surgical airway access (1%). The successful intubation rate for patients receiving paralytic agents was 97.8%. Previously published rates of prehospital surgical airway access range from 3.8 to 14.9% of patients. In this study, only 1.1% of patients required a surgical airway. We attribute this low rate to the use of paralytic agents. The availability of paralytic agents also allows expansion of the indications for prehospital airway control.