Succinylcholine-assisted intubations in prehospital care

Comparison of Intubating Conditions with Succinylcholine Versus Rocuronium in the Prehospital Setting

OBJECTIVE

Rapid sequence intubation (RSI) is frequently performed by emergency medical services (EMS). We investigated the relationship between succinylcholine and rocuronium use and time until first laryngoscopy attempt, first-pass success, and Cormack-Lehane (CL) grades.

METHODS

We included adult patients for whom prehospital RSI was attempted from July 2015 through June 2022 in a retrospective, observational study with pre-post analysis. Timing was verified using recorded defibrillator audio in addition to review of continuous ECG, pulse oximetry, and end-tidal carbon dioxide waveforms. Our primary exposure was neuromuscular blocking agent (NMBA) used, either rocuronium or succinylcholine. Our prespecified primary outcome was the first attempt Cormack-Lehane view. Key secondary outcomes were first laryngoscopy attempt success rate, timing from NMBA administration to first attempt, number of attempts, and hypoxemic events.

RESULTS

Of 5,179 patients in the EMS airway registry, 1,475 adults received an NMBA while not in cardiac arrest. Cormack-Lehane grades for succinylcholine and rocuronium were similar: grade I (64%, 59% [95% CI 0.64-1.09]), grade II (16%, 21%), grade III (18%, 16%), grade IV (3%, 3%). The median interval from NMBA administration to start of the first attempt was 57 s for succinylcholine and 83 s for rocuronium (mean difference 28 [95% CI 20-36] seconds). First attempt success was 84% for succinylcholine and 83% for rocuronium. Hypoxemic events were present in 25% of succinylcholine cases and 23% of rocuronium cases.

CONCLUSIONS

Prehospital use of either rocuronium or succinylcholine is associated with similar Cormack-Lehane grades, first-pass success rates, and rates of peri-intubation hypoxemia.

A Study of Orotracheal Intubation in Emergency Departments of Five District Hospitals in Hong Kong

Objective

To study the success rates and complications of orotracheal intubation in emergency departments of five district hospitals in Hong Kong in order to identify ways for improvement.

Method

This was a prospective observational study. The emergency department doctors performing the intubation were asked to complete an intubation study form immediately after the procedure over a period of four months. Data collected included vital signs, experiences of intubators, method of intubation and complications.

Results

A total of 347 cases were collected and 93% of them were non-trauma cases. Fifty-two percent (52%) of the cases were in cardiac arrest before intubation. Rapid sequence intubation (RSI) was applied in 36% of the cases. Junior doctors first intubated about 72% of the patients. Successful intubation was achieved in 1 and 2 attempts in 70% and 89% of the cases respectively. In 10 cases (3%), secondary methods such as laryngeal mask airway, Combitube, Trachlight or cricothyroidotomy were needed. The overall complication rate was 7.8% and the complication rate in the RSI group was 15.3%. The complication rate was even higher (20%) if intubation without medication was used in non-cardiac arrest patients. Significant drop in blood pressure was the most common complication and it could be attributed to the use of midazolam as induction medication. The success rate was found to correlate with the experience of the first intubator (p<0.05) and the laryngeal view (p<0.001). The complication rate increased with repeated attempts (p<0.001) and was higher among junior doctors (p<0.05). Early use of elastic gum bougie was associated with lower complication and higher success rates.

Conclusion

Orotracheal intubation in the emergency department was associated with high complication rate. Many complications came from junior intubators. Hypotension was the most common complication. Potentially avoidable complications may be a result of failure to use RSI in non-cardiac arrest patients and failure to use bougie in cases of poor laryngeal view.

The effect of scene time on survival

A review of the literature was carried out to determine the importance of pre-hospital scene times and how it can be affected. In the UK, and certain centres in North America, mortality and morbidity in critically injured patients appears to be related to scene times. The majority of these patients only require basic life support at the scene. Consequently the possible benefits of more advanced procedure need to be compared with the transportation period, the time needed to mobilize a medical team and skill proficiency. Cardiovascular resuscitation procedures in particular require reappraisal. Though haemostasis is essential, there is little evidence to support the use of fluid resuscitation in nontrapped urban patients with a significant haemorrhage problem. In contrast patients who are not bleeding do appear to benefit from advanced life support procedures even though this increases scene time. There is therefore a need for pre-hospital paramedic workers to triage patients so that appropriate resuscitation can be carried out.

The prehospital management of traumatic brain injury

Traumatic brain injury (TBI) is an important cause of death and disability, particularly in younger populations. The prehospital evaluation and management of TBI is a vital link between insult and definitive care and can have dramatic implications for subsequent morbidity. Following a TBI the brain is at high risk for further ischemic injury, with prehospital interventions targeted at reducing this secondary injury while optimizing cerebral physiology. In the following chapter we discuss the prehospital assessment and management of the brain-injured patient. The initial evaluation and physical examination are discussed with a focus on interpretation of specific physical examination findings and interpretation of vital signs. We evaluate patient management strategies including indications for advanced airway management, oxygenation, ventilation, and fluid resuscitation, as well as prehospital strategies for the management of suspected or impending cerebral herniation including hyperventilation and brain-directed hyperosmolar therapy. Transport decisions including the role of triage models and trauma centers are discussed. Finally, future directions in the prehospital management of traumatic brain injury are explored.

Emergency Resuscitation of Patients Enrolled in the US Diaspirin Cross-linked Hemoglobin (DCLHb) Clinical Efficacy Trial

INTRODUCTION

Optimal emergent management of traumatic hemorrhagic shock patients requires a better understanding of treatment provided in the prehospital/Emergency Medical Services (EMS) and emergency department (ED) settings. Hypothesis/Problem Described in this research are the initial clinical status, airway management, fluid and blood infusions, and time course of severely-injured hemorrhagic shock patients in the EMS and ED settings from the diaspirin cross-linked hemoglobin (DCLHb) clinical trial.

METHODS

Data were analyzed from 17 US trauma centers gathered during a randomized, controlled, single-blinded efficacy trial of a hemoglobin solution (DCLHb) as add-on therapy versus standard therapy.

RESULTS

Among the 98 randomized patients, the mean EMS Glasgow Coma Scale (GCS) was 10.6 (SD = 5.0), the mean EMS revised trauma score (RTS) was 6.3 (SD = 1.9), and the mean injury severity score (ISS) was 31 (SD = 17). Upon arrival to the ED, the GCS was 20% lower (7.8 (SD = 5.3) vs 9.7 (SD = 6.3)) and the RTS was 12% lower (5.3 (SD = 2.0) vs 6.0 (SD = 2.1)) than EMS values in blunt trauma patients (P < .001). By ED disposition, 80% of patients (78/98) were intubated. Rapid sequence intubation (RSI) was utilized in 77% (60/78), most often utilizing succinylcholine (65%) and midazolam (50%). The mean crystalloid volume infused was 4.2 L (SD = 3.4 L), 80% of which was infused within the ED. Emergency department blood transfusion occurred in 62% of patients, with an average transfused volume of 1.2 L (SD = 2.0 L). Blunt trauma patients received 2.1 times more total fluids (7.4 L vs 3.5 L, < .001) and 2.4 times more blood (2.4 L vs 1.0 L, P < .001). The mean time of patients taken from injury site to operating room (OR) was 113 minutes (SD = 87 minutes). Twenty-one (30%) of the 70 patients taken to the OR from the ED were sent within 60 minutes of the estimated injury time. Penetrating trauma patients were taken to the OR 52% sooner than blunt trauma patients (72 minutes vs 149 minutes, P < .001).

CONCLUSION

Both GCS and RTS decreased prior to ED arrival in blunt trauma patients. Intubation was performed using RSI, and crystalloid infusion of three times the estimated blood loss volume (L) and blood transfusion of the estimated blood loss volume (L) were provided in the EMS and ED settings. Surgical intervention for these trauma patients most often occurred more than one hour from the time of injury. Penetrating trauma patients received surgical intervention more rapidly than those with a blunt trauma mechanism.

Advances in prehospital trauma care

Prehospital trauma care developed over the last decades parallel in many countries. Most of the prehospital emergency medical systems relied on input or experiences from military medicine and were often modeled after the existing military procedures. Some systems were initially developed with the trauma patient in mind, while other systems were tailored for medical, especially cardiovascular, emergencies. The key components to successful prehospital trauma care are the well-known ABCs of trauma care: Airway, Breathing, Circulation. Establishing and securing the airway, ventilation, fluid resuscitation, and in addition, the quick transport to the best-suited trauma center represent the pillars of trauma care in the field. While ABC in trauma care has neither been challenged nor changed, new techniques, tools and procedures have been developed to make it easier for the prehospital provider to achieve these goals in the prehospital setting and thus improve the outcome of trauma patients.

An Algorithmic Approach to Prehospital Airway Management

Airway management, including endotracheal intubation, is considered one of the most important aspects of prehospital medical care. This concept paper proposes a systematic algorithm for performing prehospital airway management. The algorithm may be valuable as a tool for ensuring patient safety and reducing errors as well as for training rescuers in airway management.

Paramedic Rapid Sequence Intubation for Severe Traumatic Brain Injury: Perspectives from an Expert Panel

Although early intubation has become standard practice in the prehospital management of severe traumatic brain injury (TBI), many patients cannot be intubated without neuromuscular blockade. Several emergency medical services (EMS) systems have implemented paramedic rapid sequence intubation (RSI) protocols, with published reports documenting apparently conflicting outcomes effects. In response, the Brain Trauma Foundation assembled a panel of experts to interpret the existing literature regarding paramedic RSI for severe TBI and offer guidance for EMS systems considering adding this skill to the paramedic scope of practice. The interpretation of this panel can be summarized as follows: (1) the existing literature regarding paramedic RSI is inconclusive, and apparent differences in outcome can be explained by use of different methodologies and variability in comparison groups; (2) the use of Glasgow Coma Scale score alone to identify TBI patients requiring RSI is limited, with additional research needed to refine our screening criteria; (3) suboptimal RSI technique as well as subsequent hyperventilation may account for some of the mortality increase reported with the procedure; (4) initial and ongoing training as well as experience with RSI appear to affect performance; and (5) the success of a paramedic RSI program is dependent on particular EMS and trauma system characteristics.

Predictors of Intubation Success andTherapeutic Value of Paramedic Airway Management in a Large, Urban EMS System

BACKGROUND

Endotracheal intubation (ETI) is commonly used by paramedics for definitive airway management. The predictors of success and therapeutic value with regard to oxygenation are not well studied.

OBJECTIVES

1) To explore the relationship between intubation success and perfusion status, Glasgow Coma Scale (GCS) score, and end-tidal carbon dioxide (EtCO2); 2) to describe the incidence of unrecognized esophageal intubations with use of continuous capnometry; and 3) to document the incremental benefit of invasive versus noninvasive airway management techniques in correcting hypoxemia.

METHODS

This was a prospective, observational study conducted in a large urban emergency medical services system. Paramedics completed a telephone debriefing interview with quality assurance personnel following delivery of all patients in whom invasive airway management had been attempted. Continuous capnometry was used for confirmation of tube position in all patients. Descriptive statistics were used to document airway management performance, including first-attempt ETI success, overall ETI success, and Combitube insertion (CTI) success. In addition, the incidence of unrecognized esophageal intubation was recorded. The relationship between intubation success and perfusion status, GCS score, and initial EtCO2 value was explored using logistic regression. Finally, recorded SpO2 values and the incidence of hypoxemia (SpO2 < 90%) at baseline, following noninvasive airway maneuvers, and after invasive airway management were compared for perfusing patients.

RESULTS

A total of 703 patients were enrolled over 12 months. First-attempt ETI success was 61%, and overall ETI success was 81%; invasive airway management (ETI or CTI) was unsuccessful in 11% of patients. A single unrecognized esophageal intubation was observed (0.1%). A clear relationship between airway management success and perfusion status, GCS score, and initial EtCO2 value was observed. Only EtCO2 demonstrated an independent association with ETI success after adjusting for the other variables. Significant improvements in mean SpO2 and the incidence of hypoxemia over baseline were observed with both noninvasive and invasive airway management techniques in 168 perfusing patients.

CONCLUSIONS

A relationship between intubation success and perfusion status, GCS score, and initial EtCO2 value was observed. Capnometry was effective in eliminating unrecognized esophageal intubations. Both noninvasive and invasive airway management strategies were effective in increasing SpO2 values and decreasing the incidence of hypoxemia, with additional benefit observed with invasive airway maneuvers in some patients.

The Effectiveness of a Novel, Algorithm-Based Difficult Airway Curriculum for Air Medical Crews Using Human Patient Simulators

INTRODUCTION

Airway management is one of the most important skills possessed by flight crews. However, few data exist about the efficacy of various educational approaches. Traditional models for airway training, including cadaver labs, operating room exposure, and clinical apprenticeships, are scarce and offer variable educational quality. The objective of this analysis was to evaluate the effectiveness of a simulator-based difficult airway curriculum in a large, aeromedical company.

METHODS

Simulation training was integrated into existing airway training for all crew members; an original difficult airway algorithm was used to guide scenarios. To evaluate its effectiveness, rapid sequence intubation (RSI) success before and after curriculum implementation was determined. In addition, crew members rated their confidence with various aspects of airway management before and after exposure to the airway workshops.

RESULTS

First attempt and overall ETI success improved from 71.3% and 89.3% before (n=261) to 87.5% and 94.6% after (n=504) implementation of the algorithm and simulation training, whereas the incidence of hypoxic arrests during RSI decreased from 2.7% to 0.2% (p<0.01 for all comparisons). Crew members reported improvements in confidence with regard to all aspects of airway management following participation in the simulation workshops.

CONCLUSIONS

A novel, integrated airway management curriculum using treatment algorithms and simulation appeared to be effective for improving RSI success among air medical crews in this program.

Ensuring quality in prehospital airway management

PURPOSE OF REVIEW

Ensuring quality in prehospital airway management is challenging because the out-of-hospital setting is a fast-paced and unpredictable environment. The first step in meeting this challenge is the recognition by emergency medical service leaders that prehospital airway management is prone to error. Quality core values such as safety, effectiveness, timeliness, efficiency, and equity for prehospital airway management, specifically endotracheal intubation, will be discussed.

RECENT FINDINGS

Controlled studies in prehospital airway management are few. In those that have evaluated the use of endotracheal intubation in this setting, safety issues, increased scene time, and lack of effectiveness to improve outcome have been revealed.

SUMMARY

Emergency medical service administrators must critically evaluate the quality of prehospital airway management that they are providing to patients within their system by collecting the data necessary to identify quality issues and developing strategies to implement change. Research into other techniques that can provide ventilation and oxygenation to patients in the prehospital environment and that are safe and effective, such as laryngeal mask airway, need to be performed.

Hyperventilation following aero-medical rapid sequence intubation may be a deliberate response to hypoxemia

BACKGROUND

Recent studies document a high incidence of hyperventilation by prehospital providers, with a potentially detrimental effect on outcome in traumatic brain injury (TBI).

PURPOSE

To document the incidence of hyperventilation by aero-medical providers and explore a possible relationship between hyperventilation episodes and desaturations or impending hypoxemia.

METHODS

This was a prospective, descriptive study using TBI patients undergoing prehospital RSI by aero-medical crews. Continuous data regarding end-tidal CO2 (EtCO2), ventilatory rate, and oxygen saturation (SpO2) were downloaded from hand-held oximeter-capnometer devices. Two investigators independently assessed oximetry/capnometry data to identify the following occurrences: desaturation during RSI (SpO2 < 90%), impending hypoxemia (SpO2 decrease by >or=3% to a value <95%) following intubation, loss of SpO2 signal, hyperventilation (EtCO2<30 mm Hg), and severe hyperventilation (EtCO2 < 25 mm Hg). Covariate analysis was used to explore the possible association between hyperventilation episodes and either desaturation, impending hypoxemia, or loss of SpO2 signal.

RESULTS

A total of 32 aero-medical patients were enrolled with a mean duration of ventilation monitoring of 14.8 min. The incidence of hyperventilation or severe hyperventilation was substantially lower than previously documented with ground paramedics. A total of 28 hyperventilation episodes were identified in 16 patients; 13 of these were associated with impending hypoxemia following intubation, five were associated with desaturation during RSI, and seven were associated with loss of SpO2 signal. The remaining three occurred immediately following intubation without desaturation during RSI. Desaturation was observed in 62% of patients; of note, desaturation was recorded on the quality improvement document in only 23% of these. Covariate analysis revealed an association between hyperventilation episodes and either desaturatios during RSI, impending hypoxemia following intubation, or loss of SpO2 signal.

CONCLUSIONS

The incidence of hyperventilation by aeromedical crews was lower than reported for ground paramedics and appears to occur in response to desaturation, impending hypoxemia, or loss of SpO2 signal.

National Variability in Out-of-Hospital Treatment After Traumatic Injury

STUDY OBJECTIVE

The optimal out-of-hospital treatment for trauma patients remains a subject of national debate. Researchers designing future studies to address these issues must understand the variability in treatment that exists across the United States. We define the variability in the out-of-hospital treatment provided to trauma patients in the United States.

METHODS

This was a retrospective analysis of prospectively collected data for a cohort study of trauma outcomes. The study was conducted at 15 urban or suburban regions across the United States, 18 Level I trauma centers and 51 nontrauma centers. We used a weighted population sample based on data from all hospital trauma deaths and a sample of patients discharged between January 2001 and December 2002. Entry criteria included at least 1 body region with an Abbreviated Injury Score greater than 3 and age between 18 and 84 years. Exclusion criteria were patient age greater than 65 years and isolated hip fractures and patients with burns.

RESULTS

Complete out-of-hospital data were available for 3,357 patients, representing a weighted population sample of 9,929 patients. Out-of-hospital treatment varied substantially among the regions, including out-of-hospital intubation (5% to 48%), use of neuromuscular blocking agents or sedatives to facilitate intubation (0% to 100%), surgical airway access (0.1% to 3.5%), peripheral and central intravenous access (22% to 95%), and needle thoracentesis (0% to 5%).

CONCLUSION

There is considerable national variability in out-of-hospital procedures performed for trauma patients.

Prehospital rapid-sequence intubation of patients with trauma with a Glasgow Coma Score of 13 or 14 and the subsequent incidence of intracranial pathology

AIM

To identify the incidence of intracranial pathology in a population of patients with trauma with an on-scene Glasgow Coma Score (GCS) of 13 or 14, and the proportion that required prehospital intubation and ventilation.

METHOD

A retrospective review of a prehospital trauma database was carried out over a 12-month period, and 81 patients were reviewed. All had a traumatic mechanism of injury and had an on-scene GCS of 13 or 14 recorded by a prehospital doctor. 43 patients required prehospital rapid-sequence intubation. Overall, 31.5% of patients with a GCS of 13 or 14 had an abnormal computed tomography scan of the head and 20.5% had an intracranial haemorrhage.

RESULTS

For this group of patients with trauma with a drop of only one or two points on the GCS, the incidence of intracranial pathology was almost one in three and that of intracranial haemorrhage was one in five.

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 > or =3 were identified from our county trauma registry.

INTERVENTIONS

Intubated patients were stratified into 5 mm Hg arrival PCO(2) 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, PO(2), and base deficit. Increments with the highest relative survival were used to define the optimal PCO(2) range. Outcomes for patients with arrival PCO(2) 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 PCO(2) range 30-49 mm Hg. Patients with arrival PCO(2) 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 PCO(2) 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 PCO(2) 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.

The association between field Glasgow Coma Scale score and outcome in patients undergoing paramedic rapid sequence intubation

Early intubation is standard for treating severe traumatic brain injury (TBI). Aeromedical crews and select paramedic agencies use rapid sequence intubation (RSI) to facilitate intubation after TBI, with Glasgow Coma Scale (GCS) score commonly used as a screening tool. To explore the association between paramedic GCS and outcome in patients with TBI undergoing prehospital RSI, paramedics prospectively enrolled adult major trauma victims with GCS 3-8 and clinical suspicion for head trauma to undergo succinylcholine-assisted intubation as part of the San Diego Paramedic RSI Trial. The following data were abstracted from paramedic debriefing interviews and the county trauma registry: demographics, mechanism, vital signs including GCS score, clinical evidence of aspiration before RSI, arrival laboratory values, hospital course, and outcome. Paramedic GCS calculations were confirmed during debriefing interviews. Patients were stratified by GCS score, with chi-square and receiver-operator-curve (ROC) analysis used to explore the relationship between GCS and hypoxia, head injury severity, aspiration, intensive care unit (ICU) length of stay, and outcome. Cohort analysis was used to explore potential reasons for early extubation and discharge from the ICU in some patients. A total of 412 patients were included in this analysis. A total of 81 patients (20%) were extubated and discharged from the ICU in 48 h or less; these patients had higher pre-RSI oxygen saturation (SaO(2)) values and higher arrival serum ethanol levels. Paramedic and physician GCS calculations had high agreement (kappa=0.995). A statistically significant relationship was observed between GCS score and Head Abbreviated Injury Score (AIS), survival, and pre-RSI SaO(2) values. However, ROC analysis revealed a limited ability of GCS to predict the presence of severe TBI, injury severity, desaturation, aspiration, ICU length of stay, or ultimate survival. In conclusion, paramedics seem to accurately calculate GCS values before prehospital RSI. Although a relationship between paramedic GCS and outcome exists, the ability to predict the severity of injury, airway-related complications, ICU length of stay, and overall survival is limited using this single variable. Other factors should be considered to screen TBI patients for prehospital RSI.

The ability of paramedics to predict aspiration in patients undergoing prehospital rapid sequence intubation

One of the purported benefits to invasive prehospital airway management is the prevention of aspiration; however, aspiration events may occur before the arrival of prehospital personnel. We explore the timing of aspiration in patients with severe traumatic brain injury (TBI) undergoing paramedic rapid sequence intubation (RSI). Severely head-injured (Glasgow Coma Scale [GCS] score 3-8) adults were prospectively enrolled into the San Diego Paramedic RSI Trial. As part of the prehospital data collection tool, paramedics prospectively assessed for clinical evidence of aspiration before RSI (pre-intubation), aspiration events occurring during RSI (peri-RSI), and regurgitation of vomitus or blood after intubation (post-intubation). Data were abstracted from work sheets used during the RSI procedure, a telephone debriefing by one of the principal investigators immediately after delivery of the patient, and San Diego County prehospital and trauma databases. The incidence of pre-intubation aspiration, peri-RSI aspiration, and post-intubation regurgitation of vomitus or blood were determined. Patients with and without pre-intubation aspiration were compared with regard to pre- and post-intubation hypoxia and the rate of aspiration pneumonia. Logistic regression was used to explore the association between pre-intubation aspiration and various demographic and clinical factors. The results showed that pre-intubation aspiration was noted by paramedics in 72/269 patients in whom complete data were available. Peri-RSI aspiration was reported in one patient; there were no reported cases of post-intubation regurgitation of vomitus or blood. Patients in the pre-intubation aspiration group required more intubation attempts, had a higher incidence of desaturations and lower pre- and post-intubation SaO(2) values, and were more frequently diagnosed with aspiration pneumonia. Pre-intubation aspiration was associated with severe TBI, GCS score of 3, younger age, and the absence of alcohol intoxication despite controlling for age, gender, GCS, Head AIS (Abbreviated Injury Score), and serum ethanol. It is concluded that paramedics seem to be able to accurately assess for aspiration in patients undergoing prehospital RSI. The vast majority of aspiration events seem to occur before the arrival of prehospital personnel. Alteration in consciousness from TBI may carry a higher risk of aspiration than with other causes, such as alcohol intoxication.

Prehospital management of earthquake casualties buried under rubble

Earthquakes continue to exact a heavy toll on life, injury, and loss of property. Survival of casualties extricated from under the rubble depends upon early medical interventions by emergency teams on site. The objective of this paper is to review the pertinent literature and to analyze the information as a practical guideline for the medical management of casualties accidentally buried alive.

Esophageal intubation with indirect clinical tests during emergency tracheal intubation: a report on patient morbidity

STUDY OBJECTIVE

To determine the consequences of esophageal intubation (EI) when using standard indirect clinical tests to detect endotracheal tube (ETT) placement in the emergency setting outside the operating room (OR).

DESIGN

An observationally based review of a quality improvement database for emergency intubation outside the OR.

SETTING

Seven hundred sixty-five-bed tertiary care, level I trauma center in central Connecticut.

PATIENTS

Critically ill patients (n = 2377) experiencing cardiopulmonary, traumatic, septic, metabolic, or neurologic-based deterioration and requiring emergency airway management. Tracheal intubation of patients with cardiopulmonary resuscitation and chest compressions were excluded.

MEASUREMENTS

A quality improvement emergency intubation database from 1990 to 2001 was reviewed to determine the incidence of EI and its associated complications (mild and severe hypoxemia, regurgitation, aspiration, hemodynamic alteration, cardiac dysrhythmias, and cardiac arrest) when ETT position is determined by standard indirect clinical tests without the benefit of ETT-verifying devices.

RESULTS

Patients who had EI, in contrast to those who did not, had significant rates of hypoxemia (64.7% vs 13.1%; P < .001) and severe hypoxemia (Spo2 < 70%) (25% vs 4.4%; P < .001). The rate of regurgitation (24.7% vs 2.4%) and aspiration (12.8% vs 0.8%) also differed significantly (P < .001). The overall incidence of bradycardia, typically hypoxia-driven, was more common (14-fold) after EI (21.3% vs 1.5%), as was new onset cardiac dysrhythmia (6-fold increase, 23.4% vs 4.1%) and cardiac arrest (14-fold increase, 10.2% vs 0.7%), all P < .001.

CONCLUSION

These data suggest that EI during emergency intubation, when detected by standard indirect clinical tests based on physical examination, contributes significantly to mild and severe hypoxemia, regurgitation, aspiration, bradycardia, cardiac dysrhythmias, and cardiac arrest. Pursuing methods to hasten the detection of EI in the emergency setting appear warranted.

The use of neuromuscular blocking agents to facilitate prehospital intubation does not impair outcome after traumatic brain injury

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.

Opinions of Trauma Practitioners Regarding Prehospital Interventions for Critically Injured Patients

BACKGROUND

Significant controversy surrounds the prehospital management of trauma patients.

METHODS

A questionnaire describing clinical scenarios was mailed to a random sample of 345 trauma practitioners.

RESULTS

The 182 trauma practitioners (52.8%) who returned the surveys were predominantly general or trauma surgeons (83.5%) in academic or university practice (68.1%). For a patient with a severe traumatic brain injury, 84.5% of trauma practitioners recommended that emergency medical services personnel attempt intubation at least once when transport time was 20 to 40 minutes. For a patient with a gunshot wound to the epigastrium in decompensated shock, the majority of trauma practitioners believed that a relatively hypotensive state should be maintained, regardless of transport time. Trauma practitioners (52.2%) have recommended the use of the pneumatic antishock garment for transports of 20 to 40 minutes for patients with an unstable pelvic fracture and decompensated shock.

CONCLUSIONS

Most trauma practitioners believe that emergency medical services providers should attempt intubation for a patient with a severe traumatic brain injury, should treat decompensated shock in a patient with penetrating torso trauma but maintain the patient in a relatively hypotensive state, and should apply and inflate the pneumatic antishock garment for a suspected pelvic fracture accompanied by decompensated shock if the patient is 20 to 40 minutes from a trauma center. The recommendations of trauma practitioners regarding appropriate prehospital care are significantly influenced by the time required for transport to the trauma center.

Factors associated with the use of pharmacologic agents to facilitate out-of-hospital endotracheal intubation

OBJECTIVE

To identify a set of clinical factors most strongly associated with the use of drug-facilitated intubation (DFI) in the out-of-hospital setting.

METHOD

The authors used data from a prospective, multicentered endotracheal intubation (ETI) observational cohort trial, including patients from 45 emergency medical services in Pennsylvania. Providers reported clinical, physiologic, and anatomic factors associated with each ETI effort. The authors included only data from the 23 services using DFI. They identified all non-arrest (presence of a pulse) adult patients. They included both successful and failed ETIs. They defined DFI cases as patients who received a sedative or neuromuscular-blocking agent to facilitate ETI. The authors also classified patients who underwent nasotracheal intubation as DFI. They defined control subjects as patients undergoing conventional oral ETI. They performed multivariate logistic regression to identify the clinical, physiologic, and anatomic factors characteristic of DFI. They examined alternate forms of the final prediction model.

RESULTS

The authors analyzed data from 208 nonarrest patients, including 92 DFIs and 116 control subjects. Of 34 factors potentially related to DFI, 17 were excluded on univariate analysis (likelihood ratio p>0.25). Multivariate logistic regression revealed the following as positively associated with DFI: presence of clenched jaw/trismus (odds ratio [OR], 2.33; 95% confidence interval [CI], 1.10-4.95; p=0.026); increased verbal Glasgow Coma Scale score (OR, 1.71; 95% CI, 1.29-2.26; p<0.001); use of cervical spine precautions (OR, 2.30; 95% CI, 1.15-4.62; p=0.018). Anterior vocal cords (OR, 0.27; 95% CI, 0.10-0.71; p=0.004) and laryngospasm (OR, 0.14; 95% CI, 0.02-1.17; p=0.025) were negatively associated with DFI. The model showed good fit (Hosmer-Lemeshow p=0.75) and discrimination (area under the curve=0.76).

CONCLUSIONS

The authors identified a set of predictors strongly associated with DFI. These data offer insight into the current use of DFI and support the development of consensus-based guidelines for this procedure.

Incidence of transient hypoxia and pulse rate reactivity during paramedic rapid sequence intubation

STUDY OBJECTIVE

We determine the incidence of desaturation and pulse rate reactivity during paramedic rapid sequence intubation of patients with severe head injuries (Glasgow Coma Scale score <or=8).

METHODS

Adult patients with severe head injuries had recording oximeter-capnometers applied before rapid sequence intubation. Desaturation was defined as a reduction in oxygen saturation (Spo(2)) to less than 90% from an initial Spo(2) of greater than or equal to 90% or a decrease from a baseline of less than 90%. Event records were analyzed with emergency medical services (EMS) run sheets and debriefing reports.

RESULTS

Thirty-one (57%) of 54 patients demonstrated desaturation during rapid sequence intubation. Twenty-six (84%) of these 31 events occurred in patients whose initial Spo(2) value with basic airway skills was greater than or equal to 90%. The median duration of desaturation was 160 seconds (interquartile range 48 to 272 seconds), and the median decrease in Spo(2) was 22%. Six (19%) patients experienced marked bradycardia (pulse rate <50 beats/min) during desaturation events. Paramedics described rapid sequence intubation as "easy" in 26 (84%) of 31 patients with desaturation.

CONCLUSION

Out-of-hospital rapid sequence intubation by paramedics was complicated by a concerning incidence of desaturation and bradycardia. Paramedic reports did not reflect the presence of these concerning derangements. Most patients had acceptable Spo(2) values before rapid sequence intubation. An effective strategy for preoxygenation is needed before it can be concluded that rapid sequence intubation is of value in the out-of-hospital care of patients with serious closed head injury.

Paramedic-Administered Neuromuscular Blockade Improves Prehospital Intubation Success in Severely Head-Injured Patients

BACKGROUND

The purpose of this study was to evaluate the effect of paramedic-administered neuromuscular blocking agents as part of a rapid-sequence intubation (RSI) protocol on successful intubation of severely head-injured patients in a large, urban prehospital system.

METHODS

Adult head-injured patients were prospectively enrolled over 1 year using these inclusion criteria: Glasgow Coma Scale (GCS) score of 3 to 8, transport time > 10 minutes, and inability to intubate without RSI. Midazolam and succinylcholine were administered before laryngoscopy; rocuronium was given after tube placement was confirmed using capnometry, syringe aspiration, and pulse oximetry. The Combitube was used as a salvage airway device. All adult trauma victims with a GCS score of 3 to 8 were identified during the first 12 months of the study as the trial cohort and from the preceding 12 months as the control cohort. The trial and control cohorts were compared with regard to demographic data, mechanism of injury, initial vital signs, and GCS scores. The primary outcome measure was intubation success, defined as insertion of either an endotracheal tube or a Combitube, with patients stratified by GCS score.

RESULTS

The trial cohort (n = 249) and control cohort (n = 189) were similar with regard to demographic data, mechanism of injury, and initial vital signs and GCS scores. Intubation success rates increased significantly during the trial period for all patients and when stratified into GCS score of 3 and GCS score of 4 to 8. The percentage of patients intubated without neuromuscular blocking agents actually increased during the trial period. Although the number of intubations by helicopter flight crews decreased during the trial, the overall use of aeromedical resources did not change.

CONCLUSION

Paramedic-administered neuromuscular blockade as part of an RSI protocol improves intubation success in a large, urban prehospital system.

The effect of paramedic rapid sequence intubation on outcome in patients with severe traumatic brain injury

OBJECTIVE

To evaluate the effect of paramedic rapid sequence intubation (RSI) on outcome in patients with severe traumatic brain injury.

METHODS

Adult major trauma victims were prospectively enrolled over two years using the following inclusion criteria: Glasgow Coma Scale (GCS) 3-8, suspected head injury by mechanism or physical examination, transport time > 10," and inability to intubate without RSI. Midazolam and succinylcholine were administered before laryngoscopy; rocuronium was given after tube placement was confirmed using physical examination, capnometry, syringe aspiration, and pulse oximetry. The Combitube was used as a salvage airway device. For this analysis, trial patients were excluded for absence of a head injury (Head/Neck AIS score < 2), failure to fulfill major trauma outcome study criteria, unsuccessful intubation or Combitube insertion, or death in the field or in the resuscitation suite within 30" of arrival. Each study patient was hand matched to three nonintubated historical controls from our trauma registry using the following parameters: age, sex, mechanism of injury, trauma center, and AIS score for each body system. Controls were excluded for Head/Neck AIS defined by a c-spine injury or death in the field or in the resuscitation suite within 30" of arrival. chi 2, odds ratios, and logistic regression were used to investigate the impact of RSI on the primary outcome measures of mortality and incidence of a "good outcome," defined as discharge to home, rehabilitation, psychiatric facility, jail, or signing out against medical advice.

RESULTS

A total of 209 trial patients were hand matched to 627 controls. The groups were similar with regard to all matching parameters, admission vital signs, frequency of specific head injury diagnoses, and incidence of invasive procedures. Mortality was significantly increased in the trial cohort versus controls for all patients (33.0% versus 24.2%, p < 0.05) and in those with Head/Neck AIS scores of 3 or greater (41.1% versus 30.3%, p < 0.05). The incidence of a "good outcome" was lower in the trial cohort versus controls (45.5% versus 57.9%, p < 0.01). Factors that may have contributed to the increase in mortality include transient hypoxia, inadvertent hyperventilation, and longer scene times associated with the RSI procedure.

CONCLUSION

Paramedic RSI protocols to facilitate intubation of head-injured patients were associated with an increase in mortality and decrease in good outcomes versus matched historical controls.

[Rapid sequence intubation in emergency: is there any place for fentanyl?]

OBJECTIVES

Rapid sequence intubation (RSI) with the association of etomidate and succinylcholine is the French "Gold standard" for urgent "full stomach" endotracheal intubations. The aim of this study is to assess the fentanyl as a co-induction agent to take over the sedation between the RSI and the keeping of sedation, which is a critical period in which harmful neuro-vegetatives events, and awakening signs are frequently seen.

STUDY DESIGN

Randomized, double blind controlled prospective study, after acceptation by the local ethical committee.

PATIENTS AND METHODS

Three groups of patients undergoing RSI in the intensive care unit and by the out-of-hospital medical team were compared: group A patients received fentanyl 3 micrograms kg-1 during RSI, before paralysis was induced. Group B patients received the same dose of fentanyl immediately after endotracheal intubation. Group C patients did not received fentanyl (control group). Outcome measures were awakening signs arrival (respiratory movements, eyes opening, spontaneous limb movements), Ramsay score assessment, and haemody namics. Attempt at intubation and vomiting incident were also measured. Discrete data were compared by chi-2 analysis, continuous data were compared with two-way analysis of variance. A p value < 0.05 was the significant threshold.

RESULTS

Thirty-six patients were enrolled and completed the study. All the included patients presented awakening signs. The use of fentanyl did not prevent the recourse of other sedative medications. Ten minutes after endotracheal intubation, significant differences has been noticed for the awakening signs arrival between fentanyl groups (A: 42% and B: 36%) and control group (C: 77%). The Ramsay score evolution follows the same variation. All the patients were intubated on the first attempt, there was no vomiting incident noticed.

CONCLUSION

The use of fentanyl, as a co-induction agent with etomidate and succinylcholine during RSI, allows a significant delay of the awakening signs arrival and attenuate the neurovegetative response during the minutes after endotracheal intubation after RSI, without deleterious haemodynamic effects.

Role of rapid sequence induction for intubation in the prehospital setting: helpful or harmful?

Use of rapid sequence induction for intubation was introduced to the prehospital environment in the hope of enhancing patient outcome by improving early definitive airway management. Varying success has been achieved in both air and ground transport emergency medical services systems, but concern persists about the potential to cause patients harm. Individual emergency medical services systems must determine the need for rapid sequence induction for intubation and their ability to implement a rapid sequence induction for intubation protocol effectively with minimal adverse events. Therefore, the value of rapid sequence induction for intubation is dependent on each emergency medical services system design in their ability to establish personnel requirements and ongoing training, expertise in airway management skills, medical direction and supervision, and a quality assurance program. If these principles are strictly adhered to, rapid sequence induction for intubation may be safely used as an advanced airway management technique in the prehospital setting.

Paramedic-performed rapid sequence intubation of patients with severe head injuries

STUDY OBJECTIVE

We evaluate the ability of paramedic rapid sequence intubation (RSI) to facilitate intubation of patients with severe head injuries in an urban out-of-hospital system.

METHODS

Adult patients with head injuries were prospectively enrolled over a 1-year period by using the following inclusion criteria: Glasgow Coma Scale score of 3 to 8, transport time of greater than 10 minutes, and inability to intubate without RSI. Midazolam and succinylcholine were administered before laryngoscopy, and rocuronium was given after tube placement was confirmed by means of capnometry, syringe aspiration, and pulse oximetry. The Combitube was used as a salvage airway device. Outcome measures included intubation success rates, preintubation and postintubation oxygen saturation values, arrival arterial blood gas values, and total out-of-hospital times for patients intubated en route versus on scene.

RESULTS

Of 114 enrolled patients, 96 (84.2%) underwent successful endotracheal intubation, and 17 (14.9%) underwent Combitube intubation, with only 1 (0.9%) airway failure. There were no unrecognized esophageal intubations. On arrival at the trauma center, median oxygen saturation was 99%, mean arrival PO2 was 307 mm Hg, and mean arrival PCO2 was 35.8 mm Hg. Total out-of-hospital times were higher when RSI was performed on scene (26 versus 13 minutes).

CONCLUSION

Paramedics can use RSI protocols that include neuromuscular blocking and sedative agents to facilitate intubation of patients with head injuries.

An analysis of advanced prehospital airway management

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.

Regional EMS experience with etomidate for facilitated intubation

OBJECTIVE

To report the preliminary experience of the Central New York emergency medical services (EMS) region with etomidate for prehospital facilitated intubation.

METHODS

Prospective recording of all intubations (facilitated and nonfacilitated) was completed during the first six months of the etomidate protocol, from January 1 to June 30, 2000. These results were compared with retrospective comparison data obtained for an 18-month period from stored documented prehospital care reports (PCRs), a period when diazepam was used for facilitated intubation.

RESULTS

During the study period, 343 (84%) of 409 attempted intubations were successful. Of these, 24 facilitated intubations (using etomidate) were attempted (all on breathing, agitated patients), and 19 (79%, CI 63%-95%) were successful. Eighteen of these (95%) were intubated successfully on the first attempt. The median age of the patients requiring intubation was 70 years (range 14-90), and 60% were female. There were no reported incidences of vomiting, broken teeth, or bleeding. The region's prior 18-month experience using diazepam for facilitated intubation resulted in ten (23%, CI 1%-36%) successful intubations of 43 facilitated intubation attempts.

CONCLUSIONS

Preliminary data suggest increased rates of success for facilitated intubation using etomidate, when compared with diazepam, with most intubations successful on the first attempt. Limitations of this study include a small sample size and self-reporting of airway data by paramedics.

Role of the emergency medicine physician in airway management of the trauma patient

BACKGROUND

A Level I trauma center recently underwent a policy change wherein airway management of the trauma patient is under the auspices of Emergency Medicine (EM) rather than Anesthesiology.

METHODS

We prospectively collected data on 11 months of EM intubations (EMI) since this policy change and compared them to the last year of Anesthesia-managed intubations (ANI) to answer the following questions: (1) Is intubation of trauma patients being accomplished effectively by EM? (2) Has there been a change in complication rates since the policy change? (3) How does the complication rate at our trauma center compare with other institutions?

RESULTS

EM residents successfully intubated trauma patients on their first attempt 73.7% of the time compared with 77.2% ANI. The overall success rates, i.e., securing the airway within three attempts, were 97.0% (EMI) and 98.0% (ANI). The airway was successfully secured by EMI 100% of the time while a surgical airway was performed in two ANIs.

CONCLUSION

EM residents and staff can safely manage the airway of trauma patients. There is no statistically significant difference in peri-intubation complications. The complication rate for EDI (33%) and ANI (38%) is higher than reported in the literature, although the populations are not entirely comparable.

Prehospital and resuscitative airway care: should the gold standard be reassessed?

In the context of prehospital care and resuscitation, tracheal intubation has been regarded as the standard in airway treatment. The evidence for this status is rather weak. It does not take into account the level of training and experience of the personnel attempting intubation, and whether they use neuromuscular blockers. In unskilled hands, attempted tracheal intubation is harmful; unrecognized esophageal intubation is disastrous. When healthcare providers lack adequate skills in tracheal intubation, alternative airway devices, such as the laryngeal mask airway or the Combitube, may be better options than a simple facemask. Healthcare personnel using any of these devices should be adequately trained and maintain frequent practice.

Failed prehospital intubations: an analysis of emergency department courses and outcomes

OBJECTIVE

To examine the reasons for failed prehospital endotracheal intubation (ETI) and to identify how the airway was subsequently managed in the emergency department (ED).

METHODS

Data were collected from January to December 1998 for a county-wide paramedic system. Failed prehospital ETIs and perceived reasons for failure were identified. Subsequent ED airway management was reviewed.

RESULTS

During the study period there were 13,112 patient contacts resulting in ETI attempts on 592 patients, of whom 536 (90.5%) were successfully intubated. Of the 56 failed field intubations, 49 (87.5%) had ED charts available for review. Endotracheal intubation failure was associated with inadequate relaxation in 24 (49%), difficult anatomy in ten (20%), and obstruction in five (10%). Successful ETI was achieved in the ED in 42 cases (86%). Twenty cases (41%) were facilitated by rapid-sequence intubation (RSI) in the ED. For those with incomplete relaxation in the field, 13 of 24 (54%) were intubated in the ED using RSI. Factors associated with the use of ED RSI include attempted prehospital nasotracheal intubation or attempted prehospital midazolam-facilitated intubation (p < 0.001). The predicted need for RSI in this prehospital system is approximately 3.9%. In eight cases, three or more ETI attempts or the use of rescue airways was required in the ED. The predicted minimum incidence of "truly difficult" intubation in this system is approximately 0.8-1.6%.

CONCLUSIONS

Paramedic intubation failures result from a variety of factors. Less than half of field intubation failures were remedied in the ED by the use of neuromuscular-blocking agents. A similar number were intubated without the use of RSI. A fraction of failed field ETIs may have resulted from inadequate operator training or experience. A small percentage of field patients were "truly difficult" and required advanced resources in the ED to facilitate airway management. Medical directors should be cognizant of the numerous factors affecting intubation performance when designing and implementing approaches to difficult prehospital airways.

The use of midazolam for prehospital rapid-sequence intubation may be associated with a dose-related increase in hypotension

OBJECTIVE

To investigate the incidence of hypotension associated with the use of midazolam for prehospital rapid-sequence intubation (RSI).

METHODS

A retrospective review was performed using charts from the two aeromedical agencies servicing the authors' region. The RSI protocols used by crews from the northern (north) and the southern (south) parts of the region were identical, with the exception of midazolam dosing. The north crews used 0.1 mg/kg for all patients, while the south crews used 0.1 mg/kg up to a maximum of 5 mg. All patients receiving midazolam for prehospital RSI were pooled, with multiple linear regression used to investigate the relationship between midazolam dose and both hypotension and a decrease in systolic blood pressure (SBP) following RSI. Patients weighing >50 kg and patients with traumatic brain injury (TBI) were evaluated separately to determine differences between north and south with regard to midazolam dosing and incidence of hypotension. Multivariate logistical regression was used to test for these differences and for potential confounders such as age, initial SBP, and Glasgow Coma Scale score (GCS).

RESULTS

A total of 219 patients were identified from the north (n = 75) and the south (n = 144). Multiple linear regression revealed a statistically significant relationship between midazolam dose and both hypotension and an SBP decrease following RSI. There was no difference between north and south with regard to age, sex, incidence of TBI, initial SBP, or GCS. In patients >50 kg, those from the north received higher doses of midazolam and had a higher incidence of hypotension than those from the south. This relationship was also present in 184 patients with TBI.

CONCLUSION

The use of midazolam with prehospital RSI is associated with a dose-related incidence of hypotension.

Patient status and time to intubation in the assessment of prehospital intubation performance

Assessment of paramedic endotracheal intubation (ETI) performance often does not account for varied clinical conditions or the time required to complete the procedure.

OBJECTIVE

To demonstrate the utility of patient status and time to intubation (TTI) for evaluating prehospital ETI performance.

METHODS

Paramedic charts were reviewed for the period January-December 1998. Patient clinical status was defined as cardiac arrest (absence of perfusing rhythm) or non-cardiac arrest (presence of perfusing rhythm). Method, route, and success of ETI were noted. The TTI was determined as the elapsed time from on-scene arrival to securing of the endotracheal tube. Time elapsed from on-scene arrival to emergency department arrival was noted for instances of failed ETI. Statistical analysis was performed using chi-square and survival analysis (Kaplan-Meier estimator).

RESULTS

Computer records were available for 26,026 patient contacts. Of 893 documented ETI attempts, 771 (86%) were successful. The ETI success rate was significantly higher (p<0.001) for cardiac arrests (551 of 591, 93.2%) than for non-cardiac arrests (220 of 302, 72.9%). Median TTIs were 5 minutes (95% CI: 5, 5) for cardiac arrests and 17 minutes (95% CI: 14, 20) for non-cardiac arrests; this difference was significant (p<0.001). For non-cardiac arrests, ETI success was significantly (p = 0.002) higher for orotracheal intubation (OTI) (168 of 214, 78.5%) than for nasotracheal intubation (NTI) (52 of 88, 59.1%). Median TTIs were 15 minutes (95% CI: 13, 17) for OTI and 25 minutes (95% CI: 23, 27) for NTI; this difference was significant (p = 0.002). For non-cardiac arrests, the difference i

Prehospital rapid sequence induction by emergency physicians: is it safe?

OBJECTIVES

To determine if there were differences in practice or intubation mishap rate between anaesthetists and accident and emergency physicians performing rapid sequence induction of anaesthesia (RSI) in the prehospital setting.

METHODS

All patients who underwent RSI by a Helicopter Emergency Medical Service (HEMS) doctor from 1 May 1997 to 30 April 1999 were studied by retrospective analysis of in-flight run sheets. Intubation mishaps were classified as repeat attempts at intubation, repeat drug administration and failed intubation.

RESULTS

RSI was performed on 359 patients by 10 anaesthetists (202 patients) and nine emergency physicians (157 patients). Emergency physicians recorded a larger number of patients as having Cormack and Lehane grade 3 or 4 laryngoscopy than anaesthetists (p<0.0001) but were less likely to use a gum elastic bougie to assist intubation (p=0.024). Patients treated by emergency physicians did not have a significantly different pulse, blood pressure, oxygen saturation or end tidal CO2 to patients treated by anaesthetists at any time after intubation. Emergency physicians were more likely to anaesthetise patients with a Glasgow Coma Score >12 than anaesthetists (p=0.003). There were two failed intubations (1%) in the anaesthetist group and four (2.5%) in the emergency physician group. Repeat attempts at intubation and repeat drug administration occurred in <2% of each group.

CONCLUSIONS

RSI performed by emergency physicians was not associated with a significantly higher failure rate or an increased number of intubation mishaps than RSI performed by anaesthetists. Emergency physicians were able to safely administer sedative and neuromuscular blocking drugs in the prehospital situation. It is suggested that emergency physicians can safely perform rapid sequence induction of anaesthesia and intubation.

Paramedic success rate for blind nasotracheal intubation is improved with the use of an endotracheal tube with directional tip control

STUDY OBJECTIVES

Blind nasotracheal intubation (BNTI) is used to secure the airway in patients who are spontaneously breathing. The success rate for BNTI is often lower than for orotracheal intubation. We conducted this study to determine whether the use of an endotracheal tube (ETT) capable of directional tip control can improve the BNTI success rate.

METHODS

This prospective, experimental study was conducted by a state emergency medical services agency during 1997, 1998, and 1999. Consecutive patients undergoing attempted BNTI or orotracheal intubation were included. Five paramedic units were trained to use an ETT with triggeractivated distal tip directional control for BNTIs (intervention group). Ten units used conventional ETTs for BNTIs and served as concurrent controls (control group). Subjects in the 2 groups were enrolled concurrently with nonrandomized allocation based on the agency providing service. An intubation attempt was defined by tube passage, and success was defined as confirmed endotracheal placement.

RESULTS

A total of 219 BNTIs were studied (141 in the control group and 78 in the intervention group). BNTI was successful in 82 (58%) of 141 cases using conventional ETTs, and in 56 (72%) of 78 cases using directional tip control (P =.04). The overall success rate was 63%.

CONCLUSION

Use of ETTs with distal directional control is associated with a higher success rate for BNTI than conventional ETTs. Use of ETTs with directional tip control significantly improves the success rates for BNTIs.

A literature review of the prehospital use of neuromuscular blocking agents by air medical personnel to facilitate endotracheal intubation

Air medical personnel in the United States have used neuromuscular blocking agents to facilitate endotracheal intubation in the field for more than a decade. This literature review examines 15 studies to investigate their experience and explores the following specific areas: the intubation success rate in patients who did or did not receive these agents, the intubation success rate of air medical personnel before and after they incorporated these agents into their practice, the neuromuscular blocking agents and adjunct medications used by air medical personnel, and the disposition of patients who could not be intubated after an agent was given. The data suggest that, overall, air medical personnel use these agents safely and effectively. Suggestions are offered for future studies, including examining ground time when agents are used to facilitate intubation, complications of their use in this setting, and the use of simulators to train personnel in the administration of these medications.