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This edition of Air Medical Journal features a cardiovascular focus and represents our second theme issue. The first special issue (April/May/June 1999) reviewed neurologic events and was edited by William Barsan, MD, of the University of Michigan. In response to comments on that issue, a number of changes have taken place, such as the inclusion of original research in this issue. In the first of our featured articles, David Dries, MD, discusses some upcoming trends in advanced cardiac life support (ACLS) protocols. Certainly, the recent favorable data for amiodarone in out-of-hospital cardiac arrest warrant attention in acute cardiac resuscitation. Other intriguing issues include the role of glucose in resuscitation fluids and the possibifity of a shift to nonadrenergic pressor agents given the dismal performance of many ACLS drugs now used. In the second article, Jeanette Goltermann, RN, describes reperfusion strategies in patients with acute myocardial infarction. Clearly, the American health system has an insufficient number of cardiac catheterization facilities to support the demand of patients with acute coronary conditions despite the obvious benefits of acute angioplasty with stenting. Ms. Goitermann reviews some of the associated data for various medical strategies for the acute cardiac patient. Our third cardiovascular article comes from Mark Lowell, MD, medical director of Survival Flight at the University of Michigan and director of the ED chest pain unit at the university medical center. He reviews life-threatening causes of chest pain and treatment strategies for acute ischemic cardiac symptoms. Finally, Dr. Lowell addresses the question of patients who require urgent air medical transfer to a cardiac referral center. Two original research articles included in this issue compliment the topics discussed above. Leanne Perez, RN, and coworkers from Stanford Life Fright describe oxygenation and ventilation experiences associated with transportation of intubated adults. A wide variety of practices are identified in this survey of air transport agencies conducted during 1998. This work is remarkable in that 78% of surveys mailed were returned. In the second original article, Steve Talbert, RN, a flight nurse at the University of Kentucky Air Medical Service and the incoming editor of AirMed, provides some of his initial data examining propriety of use for air medical helicopters in interfacility transports. He notes that not all physiologic information is valuable in determining the need for air medical transfer. On the other hand, type and quantity of interventions with relative urgency may be more helpful in distinguishing whether the helicopter is necessary. Mr. Talbert also addresses a critical ongoing need of our industry--developing a standard for utilization. We look forward to your comments on our second theme issue as we continue into a new millennium.

This issue of Air Medical Journal includes several articles that contribute to our thinking regarding safety in medical aviation. In a review of one program’s practice of hot-loading patients in Austin, Texas, Criddle points out that it frequently is difficult to identify patients based on dispatch information who require the added effort and risk associated with loading while the rotor blades are turning. Although she uses an ingenious method (pilot logs of engine use) to identity patients receiving hot-loading, it is unclear whether all hot-loaded patients are identified in this report. Among the interesting questions raised in this article is that of public relations, a critical part of any program’s survival. Do we use hot-load status in patient transports to increase our standing with referring agencies? Do the benefits of this ap preach realistically justify the added risk? We do not have enough prospectively gathered, multicenter data to answer these questions. Given that a large number of the patients re viewed by Criddle were discharged from the hospital within 24 hours of admission, it is unclear whether prospective determination of hot-loading criteria is an effective way to identify individuals requiring this treatment and supporting this risk. In a related investigation of helicopter loading comparing hot and cold patients, Deimlmg and associates from University Air Care in Cincinnati provide additional systematic data on the time impact of hotand cold-loading strategies. These authors use prospective randomization according to day of the month to compare hotand cold-loading methods with two aircraft used to transport patients from incident scenes. As we would expect, Deimling et al. are able to demonstrate shortened ground times in patients receiving hot-load status. However, all ground times presented in this article are short. It is unclear whether the amount of time saved is suflicient to justify movement of crew members and patients under turning ro tors. To their credit, the authors make no attempt to answer this broad question. This article can be recommended for solid statistical analysis and effective demonstration of the effect of aircraft type on hotand cold-loading times with scene conditions. A survey of chemical restraint in helicopter transport is pro vided by McMullan and colleagues from the University of Mis sissippi Medical Center in Jackson. Briefly these authors examined the utilization patterns for chemical restraints in air medical transport. A telephone survey received responses from 100 air medical programs. Notably these authors reported a small but important fraction of programs at which use of chemical re straints required physician orders. Occasionally a delay in ob taming physician assent could endanger the patient. Also reported was a low incidence of patient deterioration with the use of chemical restraint. As a survey of practice, an inherent weakness is the form of subjective data provided. Nonetheless, the importance of freedom to use chemical restraints for optimal patient care and tlight program safety is emphasized. Two additional articles highlight the need for preparation to face the unknown in air medical transport. Gillen discusses the critical role of isolation precautions in protecting patients and air crew members from new classes of infectious agents, including Ebola and the filoviruses. The importance of standard precautions in the manipulation of the air medical patient is emphasized and the pathophysiology associated with these agents is reviewed succinctly. The case report of Gibbons and Goldman describes unanticipated cardiac disease in a pediatric patient requiring transfer after injury. Although crew safety is not at issue here, the uncertainty inherent in transporting patients is reaffirmed. Finally, how do we evaluate and implement strategies that incorporate safety in the air medical environment? Williams, Rose, and Simon, reporting for the Med Teams Consortium, de scribe the evolution of thinking in aviation air analysis with blame for adverse incidents now typically ascribed to system failures instead of individual performance deviation. These authors highlight the interrelatedness of all participants in air medical transport and suggest a teamwork evaluation process to optimize not only aviation safety but also medical care. Although the road to applying these and other safety concerns is a long one, these articles highlight both the need for continued appraisal of our approaches to safety for crew members and patients and some of the directions we may take.

Cardiovascular collapse due to pulmonary hyperinflation was noted in a patient with chronic obstructive pulmonary disease following median sternotomy for cardiac surgery. Treatment included bronchodilator therapy to reduce airway obstruction, limitation of minute ventilation, and increasing time available for exhalation. High inspiratory flow rates and expiratory retard may be beneficial.

Sepsis associated with respiratory failure is a major cause of morbidity and mortality in the newborn. In adult animal models, TNFα is a proinflammatory cytokine that has been associated with endotoxin-induced lung injury. We examined this association in a neonatal model of sepsis.

Despite recent advances in basic life support and advanced cardiac lie sup port and community application of these techniques, people suffering cardiac arrest outside hospitals are in imminent danger of death, particularly if initial attempts at defibrillation are unsuccessful. Much of the original work demonstrating the efficacy of community performance of cardiac life support measures comes from the Seattle area and the University of Washington. A recent clinical trial by this group suggests that outcomes in outof-hospital cardiac arrest may .be improved by administering amiodarone, an antiarrhythmia medication typically used only in the coronary care unit. Data were presented at the recent meeting of the American Heart Association in Orlando from the ARREST (amiodarone in the out-of-hospital resuscitation of refractory sustained ventricular tachyarrhythmias) study, which was conducted between November 1994 and February 1997 with 500 subjects in Seattle and Ring County, Washington. Threequarters of the subjects were men who ranged in age from 20 to 94. Study participants had ventricular fibrillation with cardiac arrest. The study group re ceived amiodarone therapy in the field in addition to standard resuscitation measures. Control individuals received standard advanced cardiac life support after basic life support measures. These investigators noted that resuscitation to a stable heart rhythm improved 26% in patients treated with intravenous amiodarone compared with patients who received standard therapy alone. Although defibrillation temporarily restored a stable rhythm, amiodarone improved the patient’s likelihood of live admission to the hospital by approximately 56%. Long-term outcome data were unavailable. Overall, a slight improvement in survival to hospital discharge was ob served in cardiac arrest victims treated with amiodarone. The major treatment endpoint for the ARREST trial was admission alive to the hospital. The ARREST trial is an example of prehospital and resuscitation research that ideally may be conducted by highly trained air medical crews. In addition to cardiac resuscitation, head injury manage ment, uncontrolled hemorrhage, acute respiratory distress, and other forms of cardiopulmonary instability are only a few areas in which the medical aviation indus try may contribute to cutting-edge research in prehospital care. The ARREST trial was funded jointly by a local research agency and the pharmaceutical industry. Similar collaboration may facilitate clinicsl trials in our industry. For more details about amiodarone in this issue, turn to “Pharmacologic Update,” a new section that will appear occasionally in Air Medical Journal. Coeditor ReneC Holleran, RN, PhD, CEN, CCRN, CFRN, discusses amiodarone and fosphenytoin.

Burn injuries are resuscitated in accord with the depth of injury and cutaneous area involved. Secondand third-degree bums are resuscitated with crystalloid solutions during the first 24 hours, the time of maximal capillary leak. Crystalloid resuscitation to compensate for capillary integrity loss and sodium shiis must be given during the entire 24 hour period. Giving the patient’s entire re suscitation volume in the initial hours after injury will only increase the total amount of resuscitation fluid required be cause the vascular integrity loss occurring after bums goes on for the full initial day. Resuscitation should be given at a consistent rate sufticient to maintain ade quate urine output and vital signs. Some programs estimate the area of patient burns and continue resuscitation using Ringer’s lactate in accord with a Parkland or Moditied Parkland formula.1 Another prehospital standard comes from the “Prehospital Bum Liie Support Course” of the National Bum Institute.2 Give Ringer’s lactate to patients with bums exceeding 20% of their total body surface if transfer time to definitive care exceeds 1 hour. Dosage recommendations based on patient age are: l Older than 15 years old: 500 ml/hr l 5 to 15 years old: 250 ml/hr l Younger than 5 years old: 150 ml/hr Initial wound care consists of simple dkbridement and topical antimicrobial application. Each of these agents has associated risks and benefits. Escharotomy may be required to maintain perfusion to threatened extremities where circumferential burns exist. In general, patients transferred after thermal injury should be kept warm and covered with clean, dry sheets. Allow the receiving center to assess the wounds and determine the type and location of topical antimicrobial agents. Initial hemodynamic response to burn injury is significantly depressed. With completion of resuscitation, however, the patient moves into a hyperdynamic phase, which is diicult to distinguish from sepsis. Thus the hemo dynamic response of burn patients will vary depending on the time patient transfer occurs. Inhalation injury is one of the factors that is an independent cause of increased mortality with a given cutaneous injury. Care in general is sup portive. The simple presence of facial bums or singed nasal hair is not an immediate indication for placement of an endotracheal tube. Critically evaluate true respiratory effort and airway patency before deciding to intubate the trachea. All patients with carbon monoxide exposure should receive 100% oxygen. Electrical injury requires administration of resuscitation fluids for deep tissue loss in excess of that predicted by cutaneous injuries. These patients may require escharotomy and fasciotomy to release vascular compression limiting perfusion of vital structures. Although these are not field proce dures, serial assessment of the peripheral neurovascular examination will allow the receiving agency to appre ciate the rapidity and significance of deficits that occur. In general, the optimal approach to chemical injuries is aggressive irrigation with water and isolation of the patient from the source of injury. Patients exposed to gasoline or petroleum products at motor vehicle crash scenes must be isolated from these products to avoid rapid absorption and later multiple organ dysfunction. Treating cold injuries involves gentle rewarming and cautious debridement of injured tissue. These patients should not be aggressively massaged or manipulated in other ways. Full demarcation may not occur with soft tissue loss for as many as 3 to 6 weeks after injury. In the acute setting, warming should not be interrupted once it is started.