Helicopter Service Research Articles

Emergency ambulance assistance in The Netherlands: is the Dutch situation optimal?

The system of prehospital trauma care in the Netherlands is the subject of great concern. Although many improvements have been achieved in the last decade, there are still some deficits. Legislation concerning the minimal level of education for ambulance attendants was recently upgraded to 'registered nurse', a standard which must be achieved by 1997. Standardization with regard to extrication techniques, equipment and methods of treatment in prehospital trauma care does not yet exist. Although aware of the fact that large regional differences exist throughout the USA, a system of care in accordance with the advanced trauma life support (ATLS) standard of the American College of Surgeons (ACS) and by means of prehospital and advanced trauma life support (PHTLS) given according to the standards of the National Association of Emergency Medical Technicians (NAEMS) was considered to be the 'golden standard'. Nineteen ground ambulance and two helicopter services in different states of the USA, working according to ACS/NAEMS standard, were visited to analyse the system of care, with special reference to (para)medical education, communication, logistics, and immobilization materials and techniques. In the Netherlands all 41 central post ambulance services (CPAs) were asked to return a questionnaire. This resulted in a 90% (37 out of 41) response. The deficits of the Dutch system of care related to the PHTLS/ATLS standard are pointed out, resulting in recommendations to improve the Dutch system. The requirements of the dispatcher are far inferior to the optimal situation, which, together with the lack of technical equipment, results in serious communication problems. The Dutch ambulance attendant education, in which in the present system the education level reaches 'registered nurse' in only 91% and specialized courses are not mandatory, should be upgraded to the PHTLS level of care.

Cholera epidemic threatens Sierra Leone

Sierra Leone faces the threat of a major epidemic of cholera with the onset of the rainy season, according to the World Health Organization (WHO). The situation is particularly grave for the two million people displaced by the country's civil war. Already 1709 cases of cholera have been registered in Freetown, with 57 deaths. Freetown's population has doubled since the start of the war in 1991 with 750,000 refugees camping out in the town. The insurgent Revolutionary United Front is now within 32 km of the capital. Provinces are cut off from the capital, medical supplies are scarce. Doctors and aid workers are forced to rely on a private helicopter service for personal transport. As many as 10,000 people were affected by the disease last year. WHO experts predict that pneumonia is likely to claim the lives of many children, and a highly drug resistant strain of Plasmodium falciparum malaria is also looming. The greatest problems are the lack of safe drinking water and the attendant risks of cholera and dysentery. At one site in Freetown the 6000 refugees have to fetch water from a well and have no latrines. As a result there have been 277 cases of cholera and 2 deaths already among that group. The health department has set up five centers to treat cholera in Freetown and is organizing mobile clinics. WHO's Sierra Leone office is assisting the government mobile health teams, which provide free primary care to displaced people. Medicines and vaccines, however, are lacking. Many of the staff of the 13 district health authorities have been displaced to Freetown. Aid agencies such as Medecins Sans Frontieres and Oxfam have stepped into the role in many districts. Ironically, one of the Revolutionary United Front's main demands is for a free national health service.

Impact of emergency medical helicopter service on mortality for trauma in north-east Italy A regional prospective audit

The hypothesis that high level on-the-field ATLS could influence mortality in severe trauma patients was tested by means of a prospective study. During a 7 month period, data of all the victims of severe involuntary trauma (road traffic accidents, work and sport accidents) in 3 Provinces of north-east Italy were entered in a database and analysed. The whole area is covered by a single emergency service which has direct control over all the ambulances and the Emergency Helicopter Service (EMHS). The area concerned by the study has a surface of 7,300 kmq with a population of 1 million inhabitants and is served by 12 first level hospitals and 4 second level institutions (trauma centres). All the patients who were still alive at the time of arrival of the first rescuers were considered, but only severe trauma patients with ISS > 15 were enclosed into the study. All the patients were followed up to their discharge from the ICUs (end point). There were three different rescue approaches: 82 Patients (GROUP A) were rescued by EMTs with BLS training, transported to the nearest level 1 hospital for stabilisation and subsequently transferred to a trauma center; 98 Patients (GROUP B) were rescued by EMTs and directly transported to a trauma centre which was the nearest institution; 42 Patients were rescued on the scene by the EMHS team including an anaesthesiologist with 10 years experience in trauma care and directly transported to a trauma centre after full on-the-field stabilisation (GROUP C) RESULTS: 222 severe trauma patients (ISS > 15) were considered. Mean ISS was 35.1 +/- 18.2 in group A, 33.4 +/- 19.6 in group B and 36.0 +/- 17.8 in group C. 67 patients died previous to ICU discharge (31%). 31 over the 82 pts in Group A (38%) died. 23 of them died even before reaching the trauma centre. The mean time elapsed between the first emergency call and the arrival at the trauma centre was 162 min (90'-300'). Mean ICU stay for patients who survived was 15 days. In Group B 31 over 98 patients (32%) died before ICU discharge. The mean time between the emergency call and hospital admission was 27'. Mean ICU stay for patients who were discharged, was 13 days. 5 over 42 patients rescued by the EMHS (Group C) died, none of them in the pre-hospital setting. Stabilisation included tracheal intubation in 34 cases (81%) and thoracic drainage in 6 (14%). All the patients arrived at the hospital with 2 i.v. line. The average amount of infused fluids were 600 mls of colloids and 810 mls of crystalloid. 13 patients with hypotension received and average of 1000 mls of colloids and 1200 mls of crystalloid. The average time elapsed between the emergency call and the final admission to the definitive care institution was 55'. Mean ICU stay was 11 days. Mortality rate in this group was 12%, significantly lower than in group A (p < 0.005) and group B (p < 0.05).

72P The Pennsylvania emergency medical service helicopter registry

72P The Pennsylvania emergency medical service helicopter registry

Does Nasotracheal Intubation Increase Complications in Patients with Skull Base Fractures?

Study objectives: To determine if the complications associated with skull base fractures are increased when nasotracheal intubation is performed in the field. Design: Retrospective, case-control study over a five-year period. Setting: A helicopter service returning to a Level I trauma center. Type of participants: All injured patients treated in the field who had either radiographic or clinical evidence of skull base fractures in whom nasotracheal intubation was attempted (38) compared with all patients with skull base fractures in whom nasotracheal intubation was not attempted (48) and a convenience sample of patients without skull base fractures in whom nasotracheal intubation was attempted (45). Patients with obvious midface motion on initial examination were excluded. Complications of skull base fractures were categorized as cerebral spinal fluid leak of longer than 24 hours and/or meningitis, cranial nerve injury, diabetes insipidus, and intracranial placement of the endotracheal tube. Interventions: Blind nasotracheal intubation was performed by experienced flight nurses. Results: There were no patients in whom an endotracheal tube was placed intracranially. There was no significant difference in complication rate between the two groups with skull base fractures (with nasotracheal intubation, 24%; 95% confidence interval, 11% to 40%; without nasotracheal intubation, 25%; 95% confidence interval, 14% to 40%). The group without skull base fracture had none of the complications usually associated with skull base fractures. Conclusion: Patients with skull base fracture have a significant complication rate (25%). The complications associated with skull base fractures are not markedly increased by attempts at nasotracheal intubation in the field.

A comparison of the costs and performance of an emergency helicopter and land ambulances in a rural area

The costs and performance of the Cornwall and Isles of Seilly Ambulance Service Helicopter Unit (CASHU) air ambulance (A/A) was assessed during 1 year (1 December 1990–30 November 1991). The helicopter, with a crew of one pilot and two paramedics, commenced 79 7 patient-related missions during the year, 554 (69.5 per cent) as an emergency response ambulance. Eighty-one (15 per cent) of the emergency missions were aborted with no patient attended. Compared with the activity of ground ambulances, the A/A attended more accidents (66.5 per cent vs 40.8 per cent), and more incidents occurring outside in fields, or on cliffs or beaches (47.1 per cent vs 9.5 per cent). In its role as an emergency response vehicle the helicopter performance was not better than that of ground ambulances. Activation times, response times and on-scene times were all longer on average than for ground ambulances. However, transport times to hospital were sometimes much faster by helicopter. Although total times from 999 call to arrival in hospital were similar in the two cohorts, this was principally because longer distances were involved in the helicopter missions. Standardized for distance the A/A was, on average, 10 min faster than predicted for a land ambulance. The estimated direct costs of CASHU were £595,000 for the year, and the costs of carrying out the helicopter missions by road have been estimated to be £97,805. The consequent marginal cost of around £500,000 must be set against any health benefits accruing from the performance improvements for patients.

Development of a pregnancy policy for air medical personnel: An administrative approach

Pregnancy of air medical personnel poses a unique challenge for the administration of air medical services. Pregnant staff vary in their approach to individual pregnancy and their desire to continue flight duties. Administrators are limited to actions that ensure optimal care for the patient regardless of the caregivers' health or condition. Air medical programs must balance what is acceptable for patient care and safety with what are legally acceptable practice restrictions. The Staff For Life helicopter service uses experts in obstetric care to evaluate the pregnant staff members' abilities to perform pre-determined physical duties associated with air medical care. A signed consent form acknowledging risk factors associated with air medical care ensures that the flight staff member has had a frank and honest discussion with her physician. The obstetric evaluation and consent form confirm for program administration a pregnant flight staff member's ability to function within her role and removes all ambiguity from the process.

Neuromuscular blockade-assisted oral intubation versus nasotracheal intubation in the prehospital care of injured patients

To compare nasotracheal intubation (NTI) to neuromuscular blockade-assisted oral intubation (NMB-assisted oral intubation) in the prehospital care of injured patients. Prospective, randomized study conducted over 21 months. A university hospital-sponsored helicopter service. Consecutive adult (more than 12 years old) injured patients at the accident scene with an initial Glasgow Coma Scale of 8 or less in whom the airway was not managed immediately by unrelaxed oral intubation or cricothyrotomy. Subjects were randomized by 24-hour time blocks into NTI or NMB-assisted oral intubation treatment groups. Forty-four were entered into the NTI group (39 randomized, two crossed over to NMB-assisted oral intubation), and 33 were entered into the NMB-assisted oral intubation group (38 randomized, seven crossed over to NTI). NMB-assisted oral intubation (succinylcholine 1.5 mg/kg IV) or NTI was carried out according to standard protocols. The success rate for NTI was 79.5% (35 of 44) and was similar to that of NMB-assisted oral intubation, 75.8% (25 of 33; chi 2 = .16; P = .69). There were no significant differences between the NTI and the NMB-assisted oral intubation groups with regard to sex, age, outcome, and Glasgow Coma Scale. For those patients in whom the initial technique was successful, NTI was significantly quicker than NMB-assisted oral intubation (mean time of NTI, 2.9 minutes; mean time of NMB-assisted oral intubation, 5.9 minutes; Mann-Whitney U, 168.0; P < .01). In the prehospital management of severely injured patients, there is no significant difference between NMB-assisted oral intubation and NTI in the rate at which endotracheal intubation is achieved. However, practitioners may prefer NTI because it requires significantly less time to perform than NMB-assisted oral intubation.

Helicopter transfer of trauma patients: the Isle of Man experience

A 10-year study of the helicopter transfer of motorcyclists injured during the International Motorcycle Tourist Trophy races (TT) and the amateur Manx Grand Prix (MGP) is reported, A total of 266 riders was transferred from the scene of the accident to hospital by air. The overall mortality rate for those riders airlifted was 3.38 per cent. The figures are compared with similar emergency helicopter services.

Does nasotracheal intubation increase complications in patients with skull base fractures?

To determine if the complications associated with skull base fractures are increased when nasotracheal intubation is performed in the field. Retrospective, case-control study over a five-year period. A helicopter service returning to a Level I trauma center. All injured patients treated in the field who had either radiographic or clinical evidence of skull base fractures in whom nasotracheal intubation was attempted (38) compared with all patients with skull base fractures in whom nasotracheal intubation was not attempted (48) and a convenience sample of patients without skull base fractures in whom nasotracheal intubation was attempted (45). Patients with obvious midface motion on initial examination were excluded. Complications of skull base fractures were categorized as cerebral spinal fluid leak of longer than 24 hours and/or meningitis, cranial nerve injury, diabetes insipidus, and intracranial placement of the endotracheal tube. Blind nasotracheal intubation was performed by experienced flight nurses. There were no patients in whom an endotracheal tube was placed intracranially. There was no significant difference in complication rate between the two groups with skull base fractures (with nasotracheal intubation, 24%; 95% confidence interval, 11% to 40%; without nasotracheal intubation, 25%; 95% confidence interval, 14% to 40%). The group without skull base fracture had none of the complications usually associated with skull base fractures. Patients with skull base fracture have a significant complication rate (25%). The complications associated with skull base fractures are not markedly increased by attempts at nasotracheal intubation in the field.

Air medical transport utilization review in North Carolina.

To perform a review of the collective experience of all hospital-based helicopter ambulances in the state of North Carolina for compliance with utilization review criteria. Flight records of the six members of the North Carolina Aeromedical Affiliation for the months of November and December 1989 were compared with utilization review criteria by an independent reviewer. A secondary review was performed by a staff member for each service. Scene responses and patients flown to a hospital other than the sponsor were evaluated. All six hospital-based helicopter services in North Carolina. All available flight records for November and December 1989. None. Of 756 transports, 747 flight records were available for review. Initial review demonstrated compliance with the criteria for 713 (95.4%) patients; secondary review showed compliance for 18 of 34 flights not meeting initial review, for an overall compliance rate of 97.9%. Compliance rates for scene responses and transports taken to a hospital other than the sponsoring facility were 96.6% and 94.1%, respectively. Review of all flights over a period of two-months by all six hospital-based helicopter services in North Carolina using utilization review criteria demonstrated a very high rate of compliance with the established criteria.

Pulse oximetry in the air rescue service. 2: Methods of increasing the stability of pulse oximetry measurements--ECG-synchronized pulse oximetry and adhesive sensors

Pulse oximetric monitoring in air rescue service (rescue helicopter) is primarily influenced by motion artifacts (especially those of a passive nature), by low perfusion and by the problem of probe dislocation. In a prospective study involving 162 unselected emergency patients treated by the medical team of the emergency helicopter service "Christoph 22" (Ulm), we studied the possibility of reducing these adverse factors by applying available state-of-the-art technology, such as ECG-synchronization and adhesive probes. By applying the thus modified methods of monitoring, the interference factor was reduced to S = 0.056, that is only 5.6% of measurement time was adversely effected. The increase in measurement stability resulted from the reduction in number of described artifacts (motion artifacts and low perfusion), as well as from the reduction in duration of interfered measurement time. ECG-synchronization very effectively influenced the passive motion artifacts. Their frequency was reduced by the factor 8.2, respectively 42. An effective reduction in number of probe dislocations can be achieved by applying adhesive probes. The high costs of such probes presently limits their application. Radiation can be eliminated by redesigning the probe. ECG-synchronization of pulse oximetric signal has proved to be a method to reduce the artifacts frequently experienced in air rescue and has considerably contributed to the increase of emergency patient safety.

Pulse oximetry in the air rescue service. 1: Quantitative detection of interfering factors on the method

The introduction of pulse oximetric monitoring in prehospital emergency medicine considerably contributed to emergency patients' safety, stability and protection. As inherent in any method of measurement, certain factors can interfere with it and limit its practical application. The emergency helicopter service at Ulm, in a prospective study involving 400 patients, systematically collected data on these limiting factors and evaluated them. The index "S" was established to quantify the time lost due to malfunctioning. Within the study group, the index average was S = 0.269, that is 26.9% of measurement time was subject to interference. The major cause was motion artifacts (68%) sensor probe dislocation (15%), low perfusion (14%) and radiation (3%). Regarding the volume of time lost due to specific interfering factors, motion artifacts (61.8%) and low perfusion (25.5%) were dominant, followed by sensor probe dislocation (10.3%) and radiation (2.4%). Interference therefore, both in time and frequency was primarily due to motion artifacts and low perfusion. The conclusions from this study led to the evaluation of two methods by which the interfering factors could be reduced: 1. ECG-synchronisation of the pulse oximetric signal; 2. The use of adhesive sensors.--The degree of increase in pulse oximetric measurement stability achieved by these two methods will be investigated in part 2 of this study.

An evaluation of the Royal Air Force helicopter search and rescue services in Britain with reference to Royal Air Force Valley 1980-1989.

The Royal Air Force (RAF) operates a helicopter Search and Rescue (SAR) service in the United Kingdom and territorial waters; it also provides a similar service in several locations abroad. A 10-year retrospective study of the SAR helicopter service operating from the RAF base at Valley on the island of Anglesey in North Wales is presented, with national SAR statistics over a similar period provided for comparison. Analysis of records kept by SAR aircrew at RAF Valley shows that their assistance had been requested on 1490 occasions during the 10-year period studied; most of these requests were the result of incidents involving holidaymakers, particularly in the mountains or along the coast. The results illustrate the versatility and life-saving potential of a highly skilled and motivated service able to work in adverse weather and dangerous locations. In the light of current debate, the value of aeromedical evacuation of seriously ill patients using helicopters is discussed.

Enhancement of a critical care transport service

The MICU has provided a much needed mode of transportation for the critically ill or injured patient in the Metro LIFE FLIGHT service area. Even though our primary focus is helicopter transport, the MICU has proved to be a valuable "backup" to our helicopter service. The MICU has paved the way to provide a more comprehensive service to the critically ill or injured patient in Northeastern Ohio, regardless of weather or lack of landing zones.

Model curriculum in air medical transport for emergency medicine residencies

[Norton EG: Model curriculum in air medical transport for emergency medicine residencies. Ann Emerg Med April 1991;20:431-432.] PURPOSE To provide a comprehensive education to emergency medicine residents in the major aspects of air medical transport with a specific emphasis on helicopter transportation. The curriculum is designed to be used as preflight training for those emergency medicine programs with helicopter services using residents as part of the flight team, or as part of a complete prehospita] education program for those residencies without helicopter services. (Presented here are goals, objectives, a suggested teaching plan, and references. An appendix outlining the air medical curriculum is available from the author.) GOALS On completion of this program, the emergency medicine graduate should be prepared to participate in air medical transport. The graduate will have a knowledge base sufficient to assist in the development of an air medical transport program, to become a medical director of an existing service, and to make appropriate decisions for referring or accepting patients to be transported by air ambulances.

EMS Response to a Major Aircraft Incident: Sioux City, Iowa

On July 19,1989, at 1515h, United Airlines flight 232 with 297 passengers and crew on board, experienced disintegration of the number 2 engine (in the tail section) while at 40-thousand feet above Alta, Iowa (Map 1). The DC-10, en route from Denver to Chicago, was diverted to Sioux City, Iowa's Gateway Airport. The disabled jet made a crash landing on an unused runway, burst apart, and caught fire upon impact. Due to the advanced warning of the potential crash, local crash-fire-rescue (CFR) units from the Air National Guard stationed at Gateway Airport, local and regional paramedic and fire units, an advanced life-support EMS helicopter service, and the two Sioux City hospitals were on alert and ready. Firefighters and Air National Guard personnel fought the fire and EMS personnel performed triage, provided emergency care in the field, and transported victims from the crash scene to local health care facilities in Sioux City. Injured victims in critical condition were transported first followed by those with lesser injuries. All were being treated within one hour and 45 minutes of the event. Of the 297 passengers and crew, 59 were admitted to local hospitals in critical condition, and 124 were treated for less severe injuries and later released.

The Impact of Emergency Medical Helicopters on Prehospital Care

Emergency medical helicopter services have grown exponentially over the past seventeen years. These services offer rapid transport by flight crews to tertiary care centers with a higher level of medical capabilities. An impact because of helicopters on survival has been well-documented for trauma patients. Assessing usage for other critical care patients remains to be delineated further.

The decision to add a second hospital-based EMS helicopter

An analysis of the first seven years of performance of our hospital-based emergency medical services (EMS) helicopter was conducted to evaluate the possible need for a second aircraft. A survey of seven hospitals currently operating two or more helicopters resulted in a consensus that one helicopter can effectively perform only 70 to 90 flights per month.The number of requests for our helicopter service has increased 148% from 610 to 1,512 in seven years while the number of completed missions has increased only 92% from 486 (40.5/month) to 935 (78/month).Requests denied due to inclement weather (265 in 1988) cannot be captured with a second visual-flight-rated (VFR) EMS helicopter; however, those missed due to maintenance requirements of the helicopter and overlapping requests (232 in 1988) can be captured.The need for a second aircraft exists when the number of requests for the service grows while the number of captured flights plateaus. Our data and industry survey suggests this will occur at 75 captured flights per month. Affordability and continued overall growth of trauma and other critical care referrals to the base hospital (s) is mandatory.This study provides a model for hospital-based EMS helicopter operators to apply to the decision whether to add a second aircraft.

Helicopter use by rural emergency departments to transfer trauma victims: A study of time-to-request intervals

To assess how soon rural emergency departments (EDs) call for helicopters to transport seriously injured patients, the records of all trauma victims (excluding isolated CNS trauma) transported by an emergency helicopter service from referring hospitals to a trauma center over an 18-month period were studied. Admission time to the referring ED was compared with the exact time a call for the helicopter was received and a time-to-request interval (TTR) was calculated. A total of 64 cases were studied. Fifty (78%) of the patients had blunt trauma; 14 (22%) had penetrating trauma. The average TTR for the helicopter was 69.8 minutes, with a range from 17 minutes before arrival at the referring ED to 337 minutes after arrival. Children (aged ≤16 years) had an average TTR of 34.1 minutes compared with 76.4 minutes for adults (aged > 16 years). Of the variables examined, patient age was the only factor significantly associated with TTR. These observations suggest that, except in children, there frequently is a lengthy time interval between the time trauma patients arrive at EDs in rural eastern North Carolina and the time an emergency helicopter service is called to transport them to a trauma center.