Pre-hospital endotracheal intubation and positive pressure ventilation is associated with hypotension and decreased survival in hypovolemic trauma patients: an analysis of the National Trauma Data Bank

Influence of the National Trauma Data Bank on the study of trauma outcomes: is it time to set research best practices to further enhance its impact?

BACKGROUND

Risk-adjusted analyses are critical in evaluating trauma outcomes. The National Trauma Data Bank (NTDB) is a statistically robust registry that allows such analyses; however, analytical techniques are not yet standardized. In this study, we examined peer-reviewed manuscripts published using NTDB data, with particular attention to characteristics strongly associated with trauma outcomes. Our objective was to determine if there are substantial variations in the methodology and quality of risk-adjusted analyses and therefore, whether development of best practices for risk-adjusted analyses is warranted.

STUDY DESIGN

A database of all studies using NTDB data published through December 2010 was created by searching PubMed and Embase. Studies with multivariate risk-adjusted analyses were examined for their central question, main outcomes measures, analytical techniques, covariates in adjusted analyses, and handling of missing data.

RESULTS

Of 286 NTDB publications, 122 performed a multivariable adjusted analysis. These studies focused on clinical outcomes (51 studies), public health policy or injury prevention (30), quality (16), disparities (15), trauma center designation (6), or scoring systems (4). Mortality was the main outcome in 98 of these studies. There were considerable differences in the covariates used for case adjustment. The 3 covariates most frequently controlled for were age (95%), Injury Severity Score (85%), and sex (78%). Up to 43% of studies did not control for the 5 basic covariates necessary to conduct a risk-adjusted analysis of trauma mortality. Less than 10% of studies used clustering to adjust for facility differences or imputation to handle missing data.

CONCLUSIONS

There is significant variability in how risk-adjusted analyses using data from the NTDB are performed. Best practices are needed to further improve the quality of research from the NTDB.

Ventilation in chest trauma

Chest trauma is one important factor for total morbidity and mortality in traumatized emergency patients. The complexity of injury in trauma patients makes it challenging to provide an optimal oxygenation while protecting the lung from further ventilator-induced injury to it. On the other hand, lung trauma needs to be treated on an individual basis, depending on the magnitude, location and type of lung or chest injury. Several aspects of ventilatory management in emergency patients are summarized herein and may give the clinician an overview of the treatment possibilities for chest trauma victims.

Hyperpressure intraperitoneal fluid administration for control of bleeding after liver injury

BACKGROUND

Acute hemorrhage is the principal cause of death in trauma patients, with most fatalities occurring during the pre-hospital phase. Recently, intra-abdominal insufflation by carbon dioxide has been shown to drastically reduce bleeding in vascular and splanchnic hemorrhagic animal models simulating the pre-hospital phase. Here, we propose that using dialysate fluid for increasing intra-abdominal pressure is at least as effective as gas with some potential advantages.

MATERIALS AND METHODS

A novel method of inducing liver trauma was used in 24 White New Zealand rabbits randomized into three groups: intra-abdominal carbon dioxide insufflation (GAS) with 15 cm H(2)O pressure; intra-abdominal infusion of type III dialysate solution (DIAL) with the same pressure; no change in intra-abdominal pressure (CTRL). All groups received intravenous resuscitation when their mean arterial pressure was below 30 mmHg. Physiologic parameters were recorded during 20 min of bleeding.

RESULTS

Red blood cell (RBC) volume loss in the DIAL and GAS was 45% and 48% lower than that in the CTRL, respectively (P < 0.0005). Similar trends were observed for losses in RBC count and hemoglobin (Hb). Final mean arterial pressure, arterial RBC, Hb, and hematocrit were higher in the DIAL and GAS than in the CTRL; glucose concentration in the DIAL group was significantly higher than that in the GAS and CTRL groups. No intravenous fluid therapy was needed in the DIAL group.

CONCLUSIONS

Hyperpressure intraperitoneal dialysate administration successfully reduced bleeding after severe liver injury in rabbits. This method can potentially be used as an adjunct to increase patient survival during pre-hospital cares.

Revisiting the value of pre-hospital tracheal intubation: an all time systematic literature review extracting the Utstein airway core variables

Introduction

Although tracheal intubation (TI) in the pre-hospital setting is regularly carried out by emergency medical service (EMS) providers throughout the world, its value is widely debated. Heterogeneity in procedures, providers, patients, systems and stated outcomes, and inconsistency in data reporting make scientific reports difficult to interpret and compare, and the majority are of limited quality. To hunt down what is really known about the value of pre-hospital TI, we determined the rate of reported Utstein airway variables (28 core variables and 12 fixed-system variables) found in current scientific publications on pre-hospital TI.

Methods

We performed an all time systematic search according to the PRISMA guidelines of Medline and EMBASE to identify original research pertaining to pre-hospital TI in adult patients.

Results

From 1,076 identified records, 73 original papers were selected. Information was extracted according to an Utstein template for data reporting from in-the-field advanced airway management. Fifty-nine studies were from North American EMS systems. Of these, 46 (78%) described services in which non-physicians conducted TI. In 12 of the 13 non-North American EMS systems, physicians performed the pre-hospital TI. Overall, two were randomised controlled trials (RCTs), and 65 were observational studies. None of the studies presented the complete set of recommended Utstein airway variables. The median number of core variables reported was 10 (max 21, min 2, IQR 8-12), and the median number of fixed system variables was 5 (max 11, min 0, IQR 4-8). Among the most frequently reported variables were "patient category" and "service mission type", reported in 86% and 71% of the studies, respectively. Among the least-reported variables were "co-morbidity" and "type of available ventilator", both reported in 2% and 1% of the studies, respectively.

Conclusions

Core data required for proper interpretation of results were frequently not recorded and reported in studies investigating TI in adults. This makes it difficult to compare scientific reports, assess their validity, and extrapolate to other EMS systems. Pre-hospital TI is a complex intervention, and terminology and study design must be improved to substantiate future evidence based clinical practice.

Anesthesia in prehospital emergencies and in the emergency department

PURPOSE OF REVIEW

Recently, notable progress has been made in the field of anesthesia drugs and airway management.

RECENT FINDINGS

Anesthesia in prehospital emergencies and in the emergency department is reviewed and guidelines are discussed.

SUMMARY

Preoxygenation should be performed with high-flow oxygen delivered through a tight-fitting face mask with a reservoir. Ketamine may be the induction agent of choice in hemodynamically unstable patients. The rocuronium antagonist sugammadex may have the potential to make rocuronium a first-line neuromuscular blocking agent in emergency induction. Experienced healthcare providers may consider prehospital anesthesia induction. Moderately experienced healthcare providers should optimize oxygenation, hasten hospital transfer and only try to intubate a patient whose life is threatened. When intubation fails twice, ventilation should be performed with an alternative supraglottic airway or a bag-valve-mask device. Lesser experienced healthcare providers should completely refrain from intubation, optimize oxygenation, hasten hospital transfer and ventilate patients only in life-threatening circumstances with a supraglottic airway or a bag-valve-mask device. Senior help should be sought early. In a 'cannot ventilate-cannot intubate' situation, a supraglottic airway should be employed and, if ventilation is still unsuccessful, a surgical airway should be performed. Capnography should be used in every ventilated patient. Clinical practice is essential to retain anesthesia and airway management skills.

The association between prehospital endotracheal intubation attempts and survival to hospital discharge among out-of-hospital cardiac arrest patients

OBJECTIVES

The benefit of prehospital endotracheal intubation (ETI) among individuals experiencing out-of-hospital cardiac arrest (OOHCA) has not been fully examined. The objective of this study was to determine if prehospital ETI attempts were associated with return of spontaneous circulation (ROSC) and survival to discharge among individuals experiencing OOHCA.

METHODS

This retrospective study included individuals who experienced a medical cardiac arrest between July 2006 and December 2008 and had resuscitation efforts initiated by paramedics from Mecklenburg County, North Carolina. Outcome variables were prehospital ROSC and survival to hospital discharge, while the primary independent variable was the number of prehospital ETI attempts.

RESULTS

There were 1,142 cardiac arrests included in the analytic data set. Prehospital ROSC occurred in 299 individuals (26.2%). When controlling for initial arrest rhythm and other confounding variables, individuals with no ETI attempted were 2.33 (95% confidence interval [CI] = 1.63 to 3.33) times more likely to have ROSC compared to those with one successful ETI attempt. Of the 299 individuals with prehospital ROSC, 118 (39.5%) were subsequently discharged alive from the hospital. Individuals having no ETI were 5.46 (95% CI = 3.36 to 8.90) times more likely to be discharged from the hospital alive compared to individuals with one successful ETI attempt.

CONCLUSIONS

Results from these analyses suggest a negative association between prehospital ETI attempts and survival from OOHCA. In this study, the individuals most likely to have prehospital ROSC and survival to hospital discharge were those who did not have a reported ETI attempt. Further comparative research should assess the potential causes of the demonstrated associations.

Anaesthesia in prehospital emergencies and in the emergency room

AIMS

To review anaesthesia in prehospital emergencies and in the emergency room, and to discuss guidelines for anaesthesia indication; pre-oxygenation; anaesthesia induction and drugs; airway management; anaesthesia maintenance and monitoring; side effects and training.

METHODS

A literature search in the PubMed database was performed and 87 articles were included in this non-systematic review.

CONCLUSIONS

For pre-oxygenation, high-flow oxygen should be delivered with a tight-fitting face-mask provided with a reservoir. In haemodynamically unstable patients, ketamine may be the induction agent of choice. The rocuronium antagonist sugammadex may have the potential to make rocuronium a first-line neuromuscular blocking agent in emergency induction. An experienced health-care provider may consider prehospital anaesthesia induction. A moderately experienced health-care provider should optimise oxygenation, fasten hospital transfer and only try to intubate a patient in extremis. If intubation fails twice, ventilation should be resumed with an alternative supra-glottic airway or a bag-valve-mask device. A lesser experienced health-care provider should completely refrain from intubation, optimise oxygenation, fasten hospital transfer and only in extremis ventilate with an alternative supra-glottic airway or a bag-valve-mask device. With an expected difficult airway, the patient should be intubated awake. With an unexpected difficult airway, bag-valve-mask ventilation should be resumed and an alternative supra-glottic airway device inserted. Senior help should be called early. In a "can-not-ventilate, can-not-intubate" situation an alternative airway should be tried and if unsuccessful because of severe upper airway pathology, a surgical airway should be performed. Ventilation should be monitored continuously with capnography. Clinical training is important to increase airway management skills.

A prospective multicenter evaluation of prehospital airway management performance in a large metropolitan region

OBJECTIVES

To determine 1) the success rate of prehospital endotracheal intubation; 2) the unrecognized tube malposition rate; and 3) predictors of tube malposition upon arrival to the emergency department (ED) in the setting of a large metropolitan area that includes 18 hospitals and 34 transporting emergency medical services (EMS) agencies.

METHODS

Prospective data were collected on patients for whom prehospital intubation was attempted between September 1, 2004, and January 31, 2005. Endotracheal tube (ETT) position upon arrival to the ED was verified by emergency medicine attending physicians. Missing cases were identified by matching prospective data with lists of attempted intubations submitted by EMS agencies, and data were obtained for these cases by retrospective chart review. Successful intubation was defined as an "endotracheal tube balloon below the cords" on arrival to the ED. Patients were the unit of analysis; proportions with 95% confidence intervals were calculated.

RESULTS

Nine hundred twenty-six patients had an attempted intubation. Methods of airway management were determined for 97.5% (825/846) of those transported to a hospital and 33.8% (27/80) of those who died in the field. For transported patients, 74.8% were successfully intubated, 20% had a failed intubation, 5.2% had a malpositioned tube on arrival to the ED, and 0.6% had another method of airway management used. Malpositioned tubes were significantly more common in pediatric patients (13.0%, compared with 4.0% for nonpediatric patients).

CONCLUSIONS

Overall intubation success was low, and consistent with previously published series. The frequency of malpositioned ETT was unacceptably high, and also consistent with prior studies. Our data support the need for ongoing monitoring of EMS providers' practices of endotracheal intubation.

Information loss in emergency medical services handover of trauma patients

INTRODUCTION

Little is known about how effectively information is transferred from emergency medical services (EMS) personnel to clinicians in the emergency department receiving the patient. Information about prehospital events and findings can help ensure expedient and appropriate care. The trauma literature describes 16 prehospital data points that affect outcome and therefore should be included in the EMS report when applicable.

OBJECTIVE

To determine the degree to which information presented in the EMS trauma patient handover is degraded.

METHODS

At a level I trauma center, patients meeting criteria for the highest level of trauma team activation ("full trauma") were enrolled. As part of routine performance improvement, the physician leadership of the trauma program watched all available video-recorded full trauma responses, checking off whether the data points appropriate to the case were verbally "transmitted" by the EMS provider. Two EMS physicians then each independently reviewed the trauma team's chart notes for 50% of the sample (and a randomly selected 15% of the charts to assess agreement) and checked off whether the same elements were documented ("received") by the trauma team. The focus was on data elements that were "transmitted" but not "received."

RESULTS

In 96 patient handovers, a total of 473 elements were transmitted, of which 329 were received (69.6%). On the average chart, 72.9% of the transmitted items were received (95% confidence interval 69.0%-76.8%). The most commonly transmitted data elements were mechanism of injury (94 times), anatomic location of injury (81), and age (67). Prehospital hypotension was received in only 10 of the 28 times it was transmitted; prehospital Glasgow Coma Scale [GCS] score 10 of 22 times; and pulse rate 13 of 49 times.

CONCLUSIONS

Even in the controlled setting of a single-patient handover with direct verbal contact between EMS providers and in-hospital clinicians, only 72.9% of the key prehospital data points that were transmitted by the EMS personnel were documented by the receiving hospital staff. Elements such as prehospital hypotension, GCS score, and other prehospital vital signs were often not recorded. Methods of "transmitting" and "receiving" data in trauma as well as all other patients need further scrutiny.

Emergency airway management in critically injured patients: a survey of U.S. aero-medical transport programs

OBJECTIVE

Pre-hospital airway management represents the intervention most likely to impact outcomes in critically injured patients. As such, airway management issues dominate quality improvement (QI) reviews of aero-medical programs. The purpose of this study was to evaluate current practice patterns of airway management in trauma among U.S. aero-medical service (AMS) programs.

METHODS

The Association of Air Medical Services (AAMS) Resource Guide from 2005 to 2006 was utilized to identify the e-mail addresses of all directors of U.S. aero-medical transport programs. Program directors from 182 U.S. aero-medical programs were asked to participate in an anonymous, web-based survey of emergency airway management protocols and practices. Non-responders to the initial request were contacted a second time by e-mail.

RESULTS

89 programs responded. 98.9% have rapid sequence intubation (RSI) protocols. 90% use succinylcholine, 70% use long-acting neuromuscular blockers (NMB) within their RSI protocol. 77% have protocols for mandatory in-flight sedation but only 13% have similar protocols for maintenance paralytics. 60% administer long-acting NMB immediately after RSI, 13% after confirmation of neurological activity. Given clinical scenarios, however, 97% administer long-acting NMB to patients with scene and in-flight Glasgow Coma Scale (GCS) of 3, even for brief transport times.

CONCLUSIONS

The majority of AMS programs have well defined RSI and in-flight sedation protocols, while protocols for in-flight NMB are uncommon. Despite this, nearly all programs administer long-acting NMB following RSI, irrespective of GCS or flight time. Given the impact of in-flight NMB on initial assessment, early intervention, and injury severity scoring, a critical appraisal of current AMS airway management practices appears warranted.

Complications of emergency tracheal intubation: hemodynamic alterations--part I

Emergency airway management outside the elective operating room presents considerable risks to the patient and significant challenges to the practitioner. Complications and adverse consequences are commonplace, yet they have not received their justified discussion or scrutiny in the literature. This review will discuss potentially life-threatening complications partitioned into 2 broad categories: hemodynamic and airway. Part 1 will focus on alterations in the heart rate and blood pressure, new onset cardiac dysrhythmias and cardiac arrest. Part 2 will explore airway related consequences such as hypoxemia, esophageal intubation, multiple intubation attempts, and aspiration.