Gary M. Vilke

The impact of prehospital endotracheal intubation on outcome in moderate to severe traumatic brain injury.

BACKGROUND Although early intubation to prevent the mortality that accompanies hypoxia is considered the standard of care for severe traumatic brain injury (TBI), the efficacy of this approach remains unproven. METHODS Patients with moderate to severe TBI (Head/Neck Abbreviated Injury Scale [AIS] score 3+) were identified from our county trauma registry. Logistic regression was used to explore the impact of prehospital intubation on outcome, controlling for age, gender, mechanism, Glasgow Coma Scale score, Head/Neck AIS score, Injury Severity Score, and hypotension. Neural network analysis was performed to identify patients predicted to benefit from prehospital intubation. RESULTS A total of 13,625 patients from five trauma centers were included; overall mortality was 22.9%, and 19.3% underwent prehospital intubation. Logistic regression revealed an increase in mortality with prehospital intubation (odds ratio, 0.36; 95% confidence interval, 0.32-0.42; p < 0.001). This was true for all patients, for those with severe TBI (Head/Neck AIS score 4+ and/or Glasgow Coma Scale score of 3-8), and with exclusion of patients transported by aeromedical crews. Patients intubated in the field versus the emergency department had worse outcomes. Neural network analysis identified a subgroup of patients with more significant injuries as potentially benefiting from prehospital intubation. CONCLUSION Prehospital intubation is associated with a decrease in survival among patients with moderate-to-severe TBI. More critically injured patients may benefit from prehospital intubation but may be difficult to identify prospectively.

Early versus Later Rhythm Analysis in Patients with Out-of-Hospital Cardiac Arrest

BACKGROUND In a departure from the previous strategy of immediate defibrillation, the 2005 resuscitation guidelines from the American Heart Association-International Liaison Committee on Resuscitation suggested that emergency medical service (EMS) personnel could provide 2 minutes of cardiopulmonary resuscitation (CPR) before the first analysis of cardiac rhythm. We compared the strategy of a brief period of CPR with early analysis of rhythm with the strategy of a longer period of CPR with delayed analysis of rhythm. METHODS We conducted a cluster-randomized trial involving adults with out-of-hospital cardiac arrest at 10 Resuscitation Outcomes Consortium sites in the United States and Canada. Patients in the early-analysis group were assigned to receive 30 to 60 seconds of EMS-administered CPR and those in the later-analysis group were assigned to receive 180 seconds of CPR, before the initial electrocardiographic analysis. The primary outcome was survival to hospital discharge with satisfactory functional status (a modified Rankin scale score of ≤3, on a scale of 0 to 6, with higher scores indicating greater disability). RESULTS We included 9933 patients, of whom 5290 were assigned to early analysis of cardiac rhythm and 4643 to later analysis. A total of 273 patients (5.9%) in the later-analysis group and 310 patients (5.9%) in the early-analysis group met the criteria for the primary outcome, with a cluster-adjusted difference of -0.2 percentage points (95% confidence interval, -1.1 to 0.7; P=0.59). Analyses of the data with adjustment for confounding factors, as well as subgroup analyses, also showed no survival benefit for either study group. CONCLUSIONS Among patients who had an out-of-hospital cardiac arrest, we found no difference in the outcomes with a brief period, as compared with a longer period, of EMS-administered CPR before the first analysis of cardiac rhythm. (Funded by the National Heart, Lung, and Blood Institute and others; ROC PRIMED ClinicalTrials.gov number, NCT00394706.).

Rapid sequence intubation in the field versus hospital in trauma patients.

We conducted a retrospective review of all adult trauma patients who underwent prehospital field rapid sequence intubation (RSI) by aeromedical crews from 1988 through 1995 and compared them to all trauma patients who arrived by ground transportation and underwent RSI in the trauma suite from 1992 through 1995 at a University hospital. Of the 47 field RSI patients, 46 (97.9%) were successfully intubated, whereas 263 of the 267 (98.5%) hospital RSI patients were successfully intubated. There were no statistical differences in success rates, number of attempts, or immediate intubation events in the procedure between the two groups. There were no differences in delayed events with the exception of pneumonia, which occurred more frequently in the field RSI group (28% vs. 6%, respectively). We performed a subgroup analysis on isolated head injury patients to evaluate outcome. There was no difference in total hospital days, length of ICU stay, mortality or final disposition in the two head injury groups. Though this study is limited by small sample size, we conclude that field RSI is equally successful and safe as hospital RSI.

Early ventilation and outcome in patients with moderate to severe traumatic brain injury.

Objectives:An increase in mortality has been reported with early intubation in severe traumatic brain injury, possibly due to suboptimal ventilation. This analysis explores the impact of early ventilation on outcome in moderate to severe traumatic brain injury. Design:Retrospective, registry-based analysis. Setting:This study was conducted in a large county trauma system that includes urban, suburban, and rural jurisdictions. Patients:Nonarrest trauma victims with a Head Abbreviated Injury Score of ≥3 were identified from our county trauma registry. Interventions:Intubated patients were stratified into 5 mm Hg arrival Pco2 increments. Logistic regression was used to calculate odds ratios for each increment, adjusting for age, gender, mechanism of injury, year of injury, preadmission Glasgow Coma Scale score, hypotension, Head Abbreviated Injury Score, Injury Severity Score, Po2, and base deficit. Increments with the highest relative survival were used to define the optimal Pco2 range. Outcomes for patients with arrival Pco2 values inside and outside this optimal range were then explored for both intubated and nonintubated patients, adjusting for the same factors as defined previously. In addition, the independent outcome effect of hyperventilation and hypoventilation was assessed. Measurements and Main Results:A total of 890 intubated and 2,914 nonintubated patients were included. Improved survival was observed for the arrival Pco2 range 30–49 mm Hg. Patients with arrival Pco2 values inside this optimal range had improved survival and a higher incidence of good outcomes. Conversely, there was no improvement in outcomes for patients within this optimal Pco2 range for nonintubated patients after adjusting for all of the factors defined previously. Both hyperventilation and hypoventilation were associated with worse outcomes in intubated but not nonintubated patients. The proportion of arrival Pco2 values within the optimal range was lower for intubated vs. nonintubated patients. Conclusions:Arrival hypercapnia and hypocapnia are common and associated with worse outcomes in intubated but not spontaneously breathing patients with traumatic brain injury.

Copeptin Helps in the Early Detection of Patients With Acute Myocardial Infarction Primary Results of the CHOPIN Trial (Copeptin Helps in the early detection Of Patients with acute myocardial INfarction)

OBJECTIVES The goal of this study was to demonstrate that copeptin levels <14 pmol/L allow ruling out acute myocardial infarction (AMI) when used in combination with cardiac troponin I (cTnI) <99 th percentile and a nondiagnostic electrocardiogram at the time of presentation to the emergency department (ED). BACKGROUND Copeptin is secreted from the pituitary early in the course of AMI. METHODS This was a 16-site study in 1,967 patients with chest pain presenting to an ED within 6 hours of pain onset. Baseline demographic characteristics and clinical data were collected prospectively. Copeptin levels and a contemporary sensitive cTnI (99 th percentile 40 ng/l; 10% coefficient of variation 0.03 μg/l) were measured in a core laboratory. Patients were followed up for 180 days. The primary outcome was diagnosis of AMI. Final diagnoses were adjudicated by 2 independent cardiologists blinded to copeptin results. RESULTS AMI was the final diagnosis in 156 patients (7.9%). A negative copeptin and cTnI at baseline ruled out AMI for 58% of patients, with a negative predictive value of 99.2% (95% confidence interval: 98.5 to 99.6). AMIs not detected by the initial cTnI alone were picked up with copeptin >14 pmol/l in 23 (72%) of 32 patients. Non-ST-segment elevation myocardial infarctions undetected by cTnI at 0 h were detected with copeptin >14 pmol/l in 10 (53%) of 19 patients. Projected average time-to-decision could be reduced by 43% (from 3.0 h to 1.8 h) by the early rule out of 58% of patients. Both abnormal copeptin and cTnI were predictors of death at 180 days (p < 0.0001 for both; c index 0.784 and 0.800, respectively). Both were independent of age and each other and provided additional predictive value (all p < 0.0001). CONCLUSIONS Adding copeptin to cTnI allowed safe rule out of AMI with a negative predictive value >99% in patients presenting with suspected acute coronary syndromes. This combination has the potential to rule out AMI in 58% of patients without serial blood draws.

Amiodarone, Lidocaine, or Placebo in Out-of-Hospital Cardiac Arrest

BACKGROUND Antiarrhythmic drugs are used commonly in out-of-hospital cardiac arrest for shock-refractory ventricular fibrillation or pulseless ventricular tachycardia, but without proven survival benefit. METHODS In this randomized, double-blind trial, we compared parenteral amiodarone, lidocaine, and saline placebo, along with standard care, in adults who had nontraumatic out-of-hospital cardiac arrest, shock-refractory ventricular fibrillation or pulseless ventricular tachycardia after at least one shock, and vascular access. Paramedics enrolled patients at 10 North American sites. The primary outcome was survival to hospital discharge; the secondary outcome was favorable neurologic function at discharge. The per-protocol (primary analysis) population included all randomly assigned participants who met eligibility criteria and received any dose of a trial drug and whose initial cardiac-arrest rhythm of ventricular fibrillation or pulseless ventricular tachycardia was refractory to shock. RESULTS In the per-protocol population, 3026 patients were randomly assigned to amiodarone (974), lidocaine (993), or placebo (1059); of those, 24.4%, 23.7%, and 21.0%, respectively, survived to hospital discharge. The difference in survival rate for amiodarone versus placebo was 3.2 percentage points (95% confidence interval [CI], -0.4 to 7.0; P=0.08); for lidocaine versus placebo, 2.6 percentage points (95% CI, -1.0 to 6.3; P=0.16); and for amiodarone versus lidocaine, 0.7 percentage points (95% CI, -3.2 to 4.7; P=0.70). Neurologic outcome at discharge was similar in the three groups. There was heterogeneity of treatment effect with respect to whether the arrest was witnessed (P=0.05); active drugs were associated with a survival rate that was significantly higher than the rate with placebo among patients with bystander-witnessed arrest but not among those with unwitnessed arrest. More amiodarone recipients required temporary cardiac pacing than did recipients of lidocaine or placebo. CONCLUSIONS Overall, neither amiodarone nor lidocaine resulted in a significantly higher rate of survival or favorable neurologic outcome than the rate with placebo among patients with out-of-hospital cardiac arrest due to initial shock-refractory ventricular fibrillation or pulseless ventricular tachycardia. (Funded by the National Heart, Lung, and Blood Institute and others; ClinicalTrials.gov number, NCT01401647.).

Comparison of wire-guided cricothyrotomy versus standard surgical cricothyrotomy technique.

e Abstract—We compared a wire-guided cricothyrotomy technique vs. standard surgical cricothyrotomy in terms of accuracy in placement, complications, performance time, incision length, and user preference. We conducted a randomized, crossover controlled trial in which Emergency Medicine (EM) attendings and residents performed cricothyrotomies by both standard and wire-guided techniques (using a commercially available kit) on human cadavers after a 15-min training session. Procedure time, incision length, and physician preference were recorded. Cadavers were inspected for accuracy of placement and complications. Airway placement was accurate in 13 of 15 cases for the standard technique (86.7%), and 14 of 15 cases for the wire-guided technique (93.3%). When comparing wireguided vs. standard techniques, there were no differences in complication rates or performance times. The wire-guided technique resulted in a significantly smaller mean incision length than the standard technique (0.53 vs. 2.53 cm, respectively, p < 0.0001). Overall, 14 of 15 physicians stated that they preferred the wire-guided to the standard technique. Our data suggest that this wire-guided cricothyrotomy technique is as accurate and timely to use as the standard technique and is preferred by our physician operators. In addition, the technique results in a smaller incision on human cadaver models.

Intubation techniques in the helicopter

The purpose of this study is an analysis of 630 field intubations of trauma patients by flight personnel of the San Diego Life Flight program. We compared nasotracheal intubation to rapid sequence induction orotracheal intubation and noninduced orotracheal intubation. We measured success of intubation route, complications, and overall patient outcome. Flight records, quality assurance flight procedure data, and hospitalization data from the San Diego Trauma Registry were reviewed over a 4-year period, from 1988 to 1991. The results of our study show that rapid sequence induction orotracheal intubation has a higher success rate, fewer complications, and a better patient outcome compared to noninduced orotracheal intubation and blind nasotracheal intubation. We recommend that rapid sequence induction oral intubation be the standard method for prehospital airway management in trauma patients.

The Combitube as a salvage airway device for paramedic rapid sequence intubation

STUDY OBJECTIVE The safety of out-of-hospital rapid sequence intubation depends on a reliable strategy when orotracheal intubation is unsuccessful. Here we describe our experience with the Combitube (esophageal-tracheal twin-lumen airway device) as a salvage airway device for paramedic rapid sequence intubation. METHODS The San Diego Paramedic Rapid Sequence Intubation Trial was performed to assess the effect of paramedic rapid sequence intubation on outcome in severely head-injured patients. Adults with severe head trauma (Glasgow Coma Scale score 3 to 8) who were unable to be intubated without medications were enrolled. Midazolam and succinylcholine were administered, and paramedics were allowed a maximum of 3 attempts at orotracheal intubation. If the attempts were unsuccessful, Combitube insertion was mandated. After confirmation of tube position, rocuronium was given and standard ventilation protocols were used. The primary outcome measure for this analysis was the success rate for Combitube insertion after unsuccessful orotracheal intubation. In addition, Combitube insertion and orotracheal intubation patients were compared with regard to demographic, clinical, and outcome data. RESULTS A total of 426 patients were enrolled in the trial, with 420 meeting inclusion criteria for this analysis. Orotracheal intubation was successful in 355 (84.5%) of 420; Combitube insertion was successful in 58 (95.1%) of 61 attempts, with no reported complications. Patients undergoing Combitube insertion had higher Face Abbreviated Injury Scale scores and were more likely to have oropharyngeal blood or vomitus. Arrival Pco(2) values were higher, and arrival Po(2) values were lower but still supranormal in patients undergoing Combitube insertion. There were no mortality differences between patients undergoing Combitube insertion and those undergoing orotracheal intubation. CONCLUSION The Combitube can be an effective salvage airway device for paramedic rapid sequence intubation in an urban/suburban, high-volume emergency medical services system with paramedics who are experienced in Combitube placement and with stringent protocols for its use. The device should be tested in other sizes and types of systems and under less medical scrutiny than was used in this study.

Successful prehospital airway management by EMT-Ds using the combitube.

Objective. To evaluate the ability to train emergency medical technicians-defibrillation (EMT-Ds) to effectively use the Combitube for intubations in the prehospital environment. Methods. This was an 18-month prospective field study in which EMT-Ds were trained how and in what situations to use the Combitube. Data were then obtained for all patients in whom Combitube insertion was attempted. Indications for use of the Combitube included: unconsciousness without a purposeful response, absence of the gag reflex, apnea or respiratory rate less than 6 breaths/min, age more than 16 years, and height at least 5 feet tall. Contraindications were: obvious signs of death, intact gag reflex, inability to advance the device due to resistance, or known esophageal pathology. Data were entered prospectively from the San Diego County EMS QANet database for prehospital providers. Results. Twenty-two EMT-D provider agencies, involving approximately 500 EMT-Ds, were included as study participants. Combitube insertions were attempted in 195 prehospital patients in cardiorespiratory arrest, with appropriate indication for Combitube use. An overall successful intubation rate (defined as the ability to successfully ventilate) of 79% was observed. Identical success rates for medical and trauma patients were noted. The device was placed in the esophagus 91% of the time. Resistance during insertion was the major reason for unsuccessful Combitube intubations. An overall hospital admission rate of 19% was observed. No complications were reported. Conclusion. EMT-Ds can be trained to use the Combitube as a means of establishing an airway in the pre-hospital setting. Future studies will need to further evaluate its effect on patient outcome.