Etomidate versus succinylcholine for intubation in an air medical setting.

The objective was to compare rates of successful endotracheal intubation (ETI) and requirement for multiple ETI attempts in patients receiving etomidate (ETOM) versus succinylcholine (SUX). This retrospective study analyzed adults in whom oral ETI was attempted by a helicopter EMS (HEMS) service between July 1997 to July 1999. Data were from records of the HEMS service, which uses a RN/EMTP crew; analysis was with chi-square and logistic regression (P = .05). ETI was successful in 269 (97.8%) of 275 patients, with multiple attempts occurring in 54 (20.1%) of 269. Success rates for SUX (209 of 213, 98.1%) and ETOM (60 of 62, 96.8%) were similar (P = .62). However, of 60 ETOM patients successfully intubated, 7 (11.7%) required rescue succinylcholine. When these patients are tallied as ETOM failures and SUX successes, resultant success rates for ETOM (86.9%) and SUX (98.2%) are different (P = .001). ETOM patients were more likely (P = .004) than SUX patients to require multiple attempts (33.3% versus 16.3%). ETI success rates were high in patients receiving SUX or ETOM as primary adjuncts for airway control, but initial success was more likely with SUX, and ETOM patients were more likely to require multiple attempts.

Appropriateness of endotracheal tube size and insertion depth in children undergoing air medical transport.

OBJECTIVES: Guidelines for pediatric endotracheal tube (ETT) size and insertion depth are important in the helicopter EMS (HEMS) setting, where intubated patients are frequently transported by a non-physician flight crew providing protocol-based care in an environment noted for limitations in clinical airway assessment. The objectives of this study were to characterize, in a HEMS pediatric population, the frequency of compliance with guideline-recommended ETT size and insertion depth, and to test for association between guideline noncompliance and subsequent receiving hospital adjustment of ETT size or insertion depth. DESIGN: This retrospective review analyzed 216 consecutive pediatric (age <14) scene and interfacility HEMS transports, of patients intubated before or during HEMS transport, by an urban two-helicopter HEMS service providing protocol-based care with a nurse/paramedic crew configuration. Patients were transported to one of three receiving academic pediatric referral centers. Pediatric Advanced Life Support (PALS) criteria for ETT size and insertion depth were used to assess guideline-appropriateness of pediatric ETTs. Receiving hospital records were reviewed to determine if post-transport ETT size or lipline adjustment were associated with guideline-appropriateness of size and lipline during HEMS transport. Univariate (chi-square and Fisher's exact) and multivariate (logistic regression) statistics were used to assess and control for the following covariates: intubator group (physician, flight crew, ground EMS), transport year, sex, age, transport type (scene versus interfacility), and receiving hospital. For all analyses, statistical significance was set at the 0.05 level. RESULTS: The initial ETT size was within 0.5 mm of guideline-recommended sizes in 178 (83.6%) of the 213 patients for whom this data were available. Inappropriate sized ETTs were nearly always (32 of 35, 91.4%) too small. Compared to initial ETTs placed by ground EMS personnel, initial ETTs placed by flight crew or physicians were more likely to be appropriate as defined by guidelines (P = .008 and .032, respectively). Receiving hospitals changed the ETT size in 18 (8.3% of 216) cases. Receiving hospital ETT size change was more likely with later transport year (P = .018) and less likely in patients over 2 years of age (P = .03); there was no significant association between receiving hospital ETT size change and intubator group (P > .22) or guideline-appropriateness of ETT size (P = 0.94). The initial ETT insertion depth was within 1 cm of the guideline-recommended lipline in 86 (43.2%) of the 199 patients for whom this data were available. Inappropriate liplines were almost always (109 of 113, 96.5%) too deep. Compared to initial ETT liplines determined by ground EMS personnel, initial liplines determined by flight crew (P = .007), but not physician (P = .47) were more likely to be appropriate as defined by guidelines. Receiving hospitals changed the ETT insertion depth in 72 (33.3% of 216) cases. Receiving hospital lipline change was more likely (P = .03) in patients older than 2 years of age, but was not associated with intubator group (P = .75) or lipline guideline-appropriateness (P = .35). CONCLUSIONS: As judged by frequently used guidelines, pediatric ETTs are often too small and commonly inserted too deep. However, this retrospective study, limited by lack of clinical correlation for ETT size and insertion depth, failed to find an association between lack of ETT size or lipline guideline compliance and subsequent ETT adjustment at receiving pediatric centers. This study's findings, which should be confirmed with prospective investigation, cast doubt upon the utility of pediatric ETT size/lipline guidelines as strict clinical or quality assurance tools for use in pediatric airway management.

Helicopter emergency medical services roles in disaster operations.

Rotor-wing aircraft have previously proven utility in disaster operations, but recent expert reviewers have identified areas of potential improvement in integration of helicopter emergency medical services (HEMS) resources into disaster planning and management. This paper discusses salient points regarding helicopter operations in disaster management, using prior reports regarding rotor-wing aircraft utilization as a basis upon which to provide a concise review of HEMS operations in disasters.

Frequency and costs of laboratory and radiograph repetition in trauma patients undergoing interfacility transfer.

Receiving trauma centers often duplicate laboratory and radiograph testing performed by referring institutions. Our objective was to quantify frequency and costs of this practice. In this prospective study of 104 consecutive interfacility-transported adult trauma patients flown by an emergency medical service to an urban level I center, flight crew noted which labs and radiographs were done at referring hospitals, which tests were sent with patients, and which were repeated on trauma center arrival. Overall, results from 246 of 283 (86.9%) laboratory tests and 241 of 249 (96.8%) radiographs done at referring hospitals were sent with patients. Repetition of laboratory tests at the receiving hospital was frequent regardless of whether initial results were sent (P = .6 by chi2), and radiograph repetition was unrelated to whether sent films were originals or copies (P = .2 by chi2). For these 104 patients, the receiving hospital charged $66,463 for repetition of work-up done at referring facilities.

Flight crew airway management in four settings: a six-year review.

OBJECTIVE: To analyze flight crew airway management in four different settings (in flight, at trauma scenes, in ambulance, and in referring hospitals) and in two different aircraft used by the same helicopter EMS (HEMS) service. The null hypothesis was that there was no association between practice setting, or aircraft, and airway practices or success rate. METHODS: This retrospective study analyzed all patients in whom advanced airway management was attempted by the HEMS service during the study period October 1991 through October 1997. Data used were from flight records of Boston MedFlight Critical Care Transport Service, which uses a nurse/paramedic crew and had a paralytic-assisted intubation protocol in place. Data were analyzed with chi-square and Fisher's exact testing, risk ratio analysis, and logistic regression. RESULTS: Advanced airway management was attempted in 722 patients, with an airway placed in 705 (97.8%). Intubation success was unrelated to site of airway management (p = 0.14), but patients were more likely to have intubation attempted prior to flight (as opposed to in flight) if the crew were in the AS365N2 Dauphin as compared with the BK-117 (p<0.0001). In addition, patients were 0.77 times as likely (95% confidence interval, 0.68-0.88) to receive paralytic-facilitated intubation if airway management occurred in the hospital setting as compared with other sites. CONCLUSIONS: While HEMS crew airway management success rates are equally high in all practice settings, airway management decision making and practice appear to be significantly influenced by practice setting and aircraft type. These data support contentions that nonphysician HEMS crews can effectively manage airways in a variety of circumstances.

Prehospital and emergency department analgesia for air-transported patients with fractures.

OBJECTIVE: To evaluate prehospital and receiving emergency department (ED) analgesia administration in air-transported patients with isolated fractures. METHODS: The study was a retrospective descriptive analysis of flight and hospital records. Study patients were consecutive adults (not pharmacologically paralyzed) with fractures undergoing scene or interfacility helicopter transport during 1994-1996. The study aeromedical program uses two helicopters staffed by a nurse/paramedic flight crew providing protocol-guided care. The receiving ED was in an urban academic Level I trauma center (annual census 65,000). Primary data collected were timing and amount of prehospital and ED analgesia. Analysis was mainly descriptive, with chi-square and nonparametric methods used to compare patients who did and did not receive intratransport fentanyl. RESULTS: 130 patients with isolated fractures underwent air transport during the study period 1994-1996. Of these, 98 (75.4%) received intratransport fentanyl; 20 of 98 (20.4%) received no analgesia in the receiving ED. Patients who did receive repeat analgesia in the receiving ED (n = 78, 79.6% of those receiving prehospital fentanyl) had a median interval of 42.5 minutes (interquartile range 25-100) between ED arrival and analgesia administration; only 62.8% of these patients received their ED analgesia within 60 minutes of arrival. CONCLUSIONS: Some patients receiving intratransport fentanyl received no ED analgesia, and those who did receive ED analgesia often had administration delays surpassing the clinical half-life of intratransport-administered fentanyl. Further study should investigate whether setting-specific analgesia practice differences reflect true differences in analgesia needs, overmedication by prehospital providers, or undermedication by ED staff.

Prehospital fentanyl analgesia in air-transported pediatric trauma patients.

OBJECTIVE: To review the 5.5-year safety record of a protocol guiding fentanyl administration to pediatric trauma patients undergoing aeromedical transport. METHODS: Retrospective review of an urban aeromedical program's trauma scene responses from October 1991 to March 1997 identified the study population as all pediatric patients (age <15 years) receiving fentanyl for analgesia during air transport. Patients receiving fentanyl concurrently with other agents, eg, paralytics, were not studied. The air transport team consisted of a flight nurse and flight paramedic who provided protocol-driven patient care with off-line medical control. Study patients' flight records were reviewed to determine vital signs (systolic blood pressure [SBP], heart rate [HR], and oxygen saturation [SAT]) before and after fentanyl administration. Postfentanyl vital signs were reviewed for evidence of hemodynamic or ventilatory compromise. Pre- and postfentanyl vital signs were compared with the paired t test (P < 0.05). Flight records were also analyzed for narrative information, eg, naloxone administration and assisted ventilation, indicative of fentanyl side effects. RESULTS: Fentanyl (0.33-5.0 microg/kg) was administered 211 times to 131 patients who had a median age of 6.2 years (0.1-14 years), median Glasgow coma score (GCS) of 9 (3-15), and a mean pediatric trauma score of 8.3+/-2.4. Seventy-nine (60.3%) patients were intubated; these patients received 139 (65.9 %) of the 211 total fentanyl doses. No adverse effects from fentanyl were noted in flight record narratives. The median interval between fentanyl administration and postfentanyl vital sign assessment was 9.5 minutes (1-35 minutes). Median postfentanyl changes in SBP and HR were -4.7 and -2.9%, respectively. No patient became hypotensive after fentanyl administration. In nonintubated patients, mean postfentanyl SAT (99.2+/-1.3%) was not significantly different (P = 0.70) from prefentanyl SAT (99.1+/-1.3%), and no patient was noted to have clinically significant SAT decrement after fentanyl. CONCLUSION: Retrospective review of more than five years of prehospital fentanyl administration revealed no untoward events. Although prospective definitive demonstration of fentanyl's field use is pending, it is reasonable to continue discretionary fentanyl administration to injured pediatric children in pain.

Guidelines on admission and discharge for adult intermediate care units. American College of Critical Care Medicine of the Society of Critical Care Medicine.

OBJECTIVE: To present guidelines for writing admission and discharge policies for adult intermediate care units. DATA SOURCES: Opinion of practitioners with experience and expertise in managing critical and intermediate care units. DATA SYNTHESIS: Consensus was reached regarding the characteristics of patients best suited for management in an intermediate care unit, as supported by a literature review. CONCLUSION: Criteria were developed that define patients who are optimal candidates for management in an intermediate care unit.

In-flight oral endotracheal intubation.

This study's goal was to analyze aeromedical emergency medical services (EMS) endotracheal intubation (ETI) success rates for in-flight intubations, and to retrospectively compare in-flight ETI success rates with those achieved in hospital and trauma scene settings. Patients undergoing flight crew ETI during a 3-year study period were reviewed, and flight team-performed intubations were classified as in-flight, hospital (at referring hospital), or ground (at trauma scene). Flight crews attempted ETI in 302 patients, with success in 291 patients (96.4%). ETI success rates for in-flight, hospital, and ground groups were 94.2%, 96.8%, and 98.3%, respectively (P = .22). There were no differences among the groups in proportions of pediatric patients (P = .55) or multiple intubation attempts (P = .83). Use of paralytic agents was more frequent in ground and in-flight groups as compared with hospital group patients (P = .03). We conclude that with the aircraft and aeromedical crew studied, ETI was as likely to be successful in-flight as in other settings.

Reduced emergency department stabilization time before cranial computed tomography in patients undergoing air medical transport.

INTRODUCTION: Advanced patient stabilization skills provided by air medical providers were hypothesized to result in streamlined emergency department (ED) stabilization of patients with head injuries requiring urgent cranial computed tomography (CCT). The goal of this study was to compare initial ED stabilization times between air- and ground-transported patients requiring urgent CCT and emergency neurosurgical hematoma evacuation. SETTING: Academic Level trauma center (annual ED census 60,000) receiving patients from ground EMS and a nurse/paramedic air medical transport team. METHODS: This retrospective study identified, from a database of 15 months of ED visits, consecutive group of adults who had CCT performed within 60 minutes of ED arrival and underwent emergent craniotomy for intracranial hematoma. Demographics, hemodynamic status, patient acuity, and time intervals between ED and CCT suite arrivals were compared between air and ground patients using chi-square, Fisher's exact, and t-tests (p = 0.05). RESULTS: Eleven air- and 39 ground-transported patients were eligible. All patient acuity data were similar between groups. Air patients were more likely to be intubated (100% versus 71.8%, p = .04) and had shorter mean ED stabilization times (29 versus 40 minutes, p = .02) than the ground. CONCLUSION: This study suggests that advanced patient stabilization offered by air medical transport may result in reduced ED stabilization time for patients requiring urgent craniotomy.

Interhospital aeromedical transports: air medical activation intervals in adult and pediatric trauma patients.

The purpose of this study was to determine whether pediatric trauma patients were transferred from community hospitals to trauma centers more expeditiously than adults of similar injury acuity. The study analyzed the air medical activation time, defined as the time delay between patient arrival at community hospitals and subsequent request for air medical transport to a Level I trauma center. Retrospective analysis of all interfacility air medical trauma transports by one service from October 1994 to June 1995 identified 40 pediatric and 156 adult patients. The mean air medical activation times for pediatric and adult trauma Interfacility transports were 36.5 and 70.1 minutes, respectively (P = .016). The study shows that community hospitals are able to expedite transfer of pediatric trauma patients and suggests that transfer delays for adult trauma patients may be reducible.

Analysis of patients discharged from receiving hospitals within 24 hours of air medical transport.

INTRODUCTION: Use review has become increasingly important in the current atmosphere of cost justification for air medical transport. One criterion for use review is patient discharge from receiving hospitals within 24 hours of transport. The objective of this study was to determine the frequency and characteristics of patients discharged within 24 hours of air transport; the goal was to identify particular patient types likely to be discharged soon after air transport. METHODS: Flight records from November 1994 to September 1995 were reviewed. Follow-up identified patients who were discharged within 24 hours of air medical transport; these were designated the "24-hour group." Other patients were designated the "overall group." Comparisons between groups were made using the t test, Wilcoxon rank sum, and chi-square analysis (alpha = 0.05) for the following factors: age, vital signs, Glasgow coma score, percentage of intubated patients, and percentage of trauma and scene transports. RESULTS: Of the 945 flights analyzed, 42 (4.4%) transported patients who were discharged within 24 hours of air transport. Patients in the 24-hour group were younger, less likely to be intubated, and more likely to be scene-trauma transports compared with the overall group. CONCLUSION: This study demonstrates that air medical transports meet currently accepted criteria for helicopter transport. This study suggests that inappropriate air medical transport is rare, even in patients discharged from receiving hospitals within 24 hours of air transport.

Cabin configuration and prolonged oral endotracheal intubation in the AS365N2 Dauphin EMS helicopter.

INTRODUCTION: Most patients transported by air who require endotracheal intubation undergo endotracheal intubation before transport. However, in-flight endotracheal intubation may be indicated in the setting of certain scene conditions, in-flight patient deterioration, or endotracheal tube dislodgement. A previous report of high endotracheal intubation efficacy in the BK-117 in-flight recommended that flight programs review endotracheal intubation capabilities in their own aircraft. This study was conducted to determine whether in-aircraft endotracheal intubation times in the AS365N2 Dauphin were comparable to those previously reported for the BK-117. SETTING: AS365N2 and BK-117 helicopters stationary on a helipad. METHODS: Eight flight team members per formed three mannequin endotracheal intubations in each aircraft. Three time intervals were assessed: Setup, time required for equipping and positioning for endotracheal intubation; placement, time from laryngoscopy to endotracheal intubation; and total (Setup + Placement). Mean times for the BK-117 and AS365N2 were compared using the t test (a=0.05). RESULTS: All endotracheal intubation attempts were successful, but setup (p=0.0001), placement (p=0.0271), and total (p=0.0011) times were longer in the Dauphin. Crew members unanimously expressed endotracheal intubation difficulty caused by positioning problems in the Dauphin. CONCLUSION: In-aircraft intubation is significantly more time-consuming in the Dauphin than in the BK-117. This prolongation of intubation appears to be due to problems with positioning of the air medical crew and patient.

Regionalization of critical care medicine: task force report of the American College of Critical Care Medicine.

OBJECTIVES: To review the existing literature and task force opinions on regionalization of critical care services, and to synthesize a judgement on possible costs, benefits, disadvantages, and strategies. DATA SOURCES: Pertinent literature in the English language. STUDY SELECTION: One hundred forty-six English language papers were studied to determine possible ramifications of regionalization of critical care or other similar services. DATA EXTRACTION: Information on possible influence on the care of the critically ill was sought and integrated with the opinions of task force members. Possible costs, benefits, as well as disadvantages to the patient, transferring and receiving institutions, and region as a whole were sought. DATA SYNTHESIS: Regionalization of critical care services was thought to be advantageous to the patient. The larger academic institutions tend to have more resources, better subspecialty availability, and expertise in the care of the critically ill. Efficiency and safety during transport need to be in place. Disadvantages of overutilization, possible costliness to both the referring institution as well as to the receiving institution were outlined. It was agreed that pediatric critical care medicine was a separate issue. CONCLUSIONS: Regionalization of critical care medicine probably is beneficial and the concept should be explored.

The efficacy of sequential compression devices in multiple trauma patients with severe head injury.

Thirty-two multiple trauma patients with severe head injury and a Glasgow Coma Scale (GCS) score of 8 or less were prospectively studied to assess the occurrence of deep venous thrombosis (DVT) and pulmonary embolism (PE). All patients required mechanical ventilation. A sequential compression device (SCD) was used in 14 patients and 18 patients received no prophylaxis for thromboembolism. Bilateral lower extremity technetium venoscans and ventilation/perfusion (V/Q) lung scans were performed within 6 days of admission and every week for 1 month or until the patient developed DVT or PE or was discharged from the SICU. Deep venous thrombosis occurred in two patients (6%) at 16 and 28 days following trauma. Twenty-five patients had normal or low probability V/Q scans. Six had high probability V/Q scans confirmed by pulmonary arteriograms (PAGs) at 12.5 +/- 4 days. Clinical signs of PE were absent in all patients with a positive PAG. There were no differences in age, Injury Severity Score (ISS), GCS Score, APACHE II Score, or Trauma Score between the patients who developed DVT or PE and those who did not. A SCD was used in four of the eight patients with DVT or PE. All but one patient with DVT or PE underwent placement of a vena caval filter. Multiple trauma patients with severe head injury (GCS score < or = 8) are at high risk for thromboembolism. The available means of prevention and diagnosis of DVT or PE in multiple trauma patients with severe head injury are not entirely effective.

Management of the trauma patient with pre-existing renal disease.

Chronic renal disease is associated with fluid retention, electrolyte disturbances, anemia, platelet dysfunction, malnutrition, and, often, underlying disease such as diabetes, hypertension, and coronary artery disease. The mortality and morbidity of trauma increases when the victim has pre-existing renal disease. Special attention must be given to fluid resuscitation in these patients because of their limited or absent ability to excrete solutes and fluids. Invasive hemodynamic monitoring is helpful in guiding the resuscitation efforts because urine output and acid-base balance are unreliable markers. Knowledge of pharmacokinetics and pharmacodynamics is necessary in patients with renal disease. Choice of therapy for solute and fluid removal depends on the patient's hemodynamic status, the presence or absence of coagulopathy, and the type of traumatic injury. Renal replacement therapies are recommended for hemodynamically compromised patients.

Drug removal during continuous arteriovenous hemofiltration: theory and clinical observations.

We have discussed the basic principles of pharmacokinetics and convective solute removal in the context of each other. Clinical observations appear to follow the theoretical expectations. For practical purposes plasma and plasma water are not different. In the calculation of drug sieving, venous samples do not contribute enough to warrant their extra costs. We recommend that drug removal in hemofiltration be expressed by the sieving coefficient, UF/A. Drug sieving data in humans undergoing CAVH are tabulated. Recommendations for supplemental dosing are discussed which are applicable to any clinical setting.