Tim Harrison

Helicopter Transport and Blunt Trauma Mortality: A Multicenter Trial

BACKGROUND Despite many studies addressing potential impact of helicopter transport on trauma mortality, debate as to the efficacy of air transport continues. METHODS This retrospective study combined trauma registry data from five urban Level I adult and pediatric centers. Logistic regression assessed effect of helicopter transport on mortality while adjusting for age, sex, transport year, receiving hospital, prehospital level of care (Advanced Life Support vs. Basic Life Support), ISS, and mission type (scene vs. interfacility). RESULTS The study database comprised 16,699 patients. Crude mortality for Air (9.4%) was 3.4 times (95% CI, 2.9-4.0, p < 0.001) that of Ground (3.0%) patients. In adjusted analysis, helicopter transport was found to be associated with a significant mortality reduction (odds ratio, 0.76; 95% CI, 0.59-0.98; p = 0.031). CONCLUSION The results of this study are consistent with an association between helicopter transport mode and increased survival in blunt trauma patients.

Isolated prehospital hypotension after traumatic injuries: a predictor of mortality? ☆

In patients with traumatic injuries, prehospital hypotension that resolves by Emergency Department (ED) arrival is of uncertain significance. We examined the impact of prehospital hypotension (PH) in normotensive ED patients with traumatic injuries on predicting mortality and chest/abdominal operative intervention. A retrospective cohort study was conducted of consecutive patients undergoing helicopter transport to two trauma centers between 1993 and 1997. Outcomes were mortality and chest or abdominal operative intervention. Of 545 scene transports, 55 (10.1%) patients were hypotensive on ED arrival, leaving 490 normotensive ED patients. Of 490 patients, 35 (7%) had PH and 455 (93%) had no PH. Multiple logistic regression showed the PH group to have a relative risk for death of 4.4 (95% CI: 1.2-16.6, p < 0.03) and for chest or abdominal operative intervention of 2.9 (1.1-7.6, p < 0.03). In this study of normotensive trauma center patients, prehospital hypotension was associated with increased risk of mortality and significant chest or abdominal injury.

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 Fishers 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.

Success rates of pediatric intubation by a non-physician-staffed critical care transport service.

Objectives: Previous researchers have found that institution of an endotracheal intubation (ETI) protocol into a large urban paramedic program resulted in low success rates and had no beneficial effects. The primary goal of the current study was to assess ETI success rates achieved by a small cadre of nonphysician critical care transport (CCT) providers. A secondary objective was to assess for association between ETI success and factors such as age group or ETI setting (eg, in-hospital, in-aircraft). Design: This retrospective study analyzed transport records of consecutive pediatric patients (younger than 13 years) in whom ETI was attempted by a nurse/paramedic (RN/EMTP) CCT crew working under protocols which included neuromuscular blockade (NMB)-facilitated ETI. The CCT service performs scene and interfacility transports in helicopter, fixed-wing (airplane), and ground critical care vehicles; pediatric patients are transferred to 4 receiving tertiary care centers. χ2 test, Fisher exact test, and logistic regression analysis (P = 0.05) examined ETI success rates and assessed for association between ETI success and various characteristics (eg, age group, ETI setting). Results: The CCT crew attempted ETI in 143 patients, with success in 136 cases (95.1%). There were no unrecognized esophageal intubations. ETI success was of similar likelihood across pediatric age groups (P = 0.19) and in different ETI settings (P = 0.57). Conclusions: CCT crew airway management success was very high in all practice settings. These data support contentions that, with a high level of initial and ongoing training, nonphysician CCT crew can successfully manage pediatric airways in a variety of circumstances.

In-flight oral endotracheal intubation

This studys 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.

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.

What Happens to Spo2 During Air Medical Crew Intubations

Objectives. Studies finding adverse outcomes associated with emergency medical services intubation (ETI) have prompted recommendations for prehospital services to improve tracking of oxygenation during airway management. Our goals were to 1) implement a documentation requirement for helicopter EMS (HEMS) crews, entailing tracking andnotation of the lowest SpO2 value (peri-ETI SpO2 nadir) occurring during HEMS crew ETI, and2) assess the findings associated with the peri-ETI SpO2 documentation parameter. Methods. This was a prospective study conducted at an urban HEMS program with flight nurse/flight paramedic staffing andprotocol-driven care. There were 200 consecutive cases undergoing HEMS ETI between April 2004 andJuly 2005. Univariate logistic regression with odds ratio (OR) was used to assess for association between ETI-related hypoxemia (decrease in SpO2 value to < 90% during ETI) andpatient/intubator characteristics. Results. HEMS crew ETI was successful in 189 (95.4%) of the 200 patients. The lowest peri-ETI SpO2 value was specifically documented in 170 patients (85%) in the study group. In univariate analysis, successful crew ETI was correlated with avoidance of crew-recorded SpO2 value decreasing to < 90% (OR, 0.23; 95% confidence interval, 0.07–0.83). Similarly, requirement for multiple attempts at ETI was correlated with higher likelihood that crews recorded peri-ETI SpO2 value decreasing to < 90% (OR, 7.8; 95% confidence interval, 3.2–18.8). However, in nearly two thirds of cases in which multiple attempts were executed, the peri-ETI SpO2 value remained > 90%. Of the seven patients in whom rescue laryngeal mask airways were placed, the peri-ETI SpO2 value remained > 90% in three (42.9%). Conclusion. Documentation of crew-recorded peri-ETI SpO2 nadir is a useful andpractical prehospital data point.

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.

Airway management in the air medical setting

Abstract Research into air medical team airway management practice has answered many questions and demonstrated the ability of flight crews to manage even the most difficult airways effectively. Further study in air medicine will continue to refine airway management protocols to result in maximum safety and efficacy for air-transported patients.