Characteristics and toxicological processing of postmortem pilot specimens* from fatal civil aviation accidents

INTRODUCTION: Autopsied biosamples from civil aviation accident pilot fatalities are submitted to the Civil Aerospace Medical Institute (CAMI) for toxicological evaluation. However, such evaluation is dependent on types and amounts of submitted samples, and obtaining suitable samples is governed by the nature of the accident. Characteristics of those samples and associated toxicological processing have not been well documented in the literature. METHOD: Therefore, the CAMI Toxicology Database was searched for these aspects. RESULTS: CAMI received samples from the pilot fatalities (CAMI cases) of approximately 80% of the 1990-2000 aviation accidents reported by the National Transportation Safety Board. Accidents and cases during June-September were higher than the other months, and more than half of the received cases had multiple samples in sufficient amounts. For example, out of 1891 cases processed for the 1996-2000 accidents, 1211 had at least adequate amounts of blood, urine, and/or vitreous humor; 324 had inadequate amounts of blood and urine; and 356 had no blood or urine. Muscle, liver, lung, and/or kidney samples were submitted in 90% of the cases, while cerebrospinal fluids were submitted in only 8% of the cases. The toxicologically preferred samples, blood and urine, were available in 78% and 56% of the 1891 cases, respectively. Out of 51 cases containing only one sample type, 46 had muscle and the remaining 5 had other sample types. Samples were primarily analyzed for combustion gases, alcohol/volatiles, and drugs. Generally, the presence of analytes is demonstrated in at least two different sample types by using two different analytical techniques for reporting a particular case as "positive." An effective quality-assurance/quality-control is maintained throughout the process. CONCLUSION: In the majority of the aviation accidents, sufficient amounts and types of biological samples were submitted for toxicological evaluation.     

Prevalence of cardiovascular abnormalities in pilots involved in fatal general aviation airplane accidents

INTRODUCTION: Cardiovascular disease in general and coronary heart disease in particular remains the leading cause of morbidity and mortality in developed countries. Coronary artery disease is of concern in aviation because of its potential to cause sudden in-flight incapacitation. The purpose of this study was to analyze the cardiovascular abnormalities in pilots involved in fatal general aviation airplane accidents. METHOD: A comprehensive review was performed of all cardiovascular abnormalities detected during autopsies conducted on pilots involved in fatal fixed-wing general aviation aircraft accidents in the U.S. from 1996-1999. Data was obtained from the database maintained at Civil Aerospace Medical Institute in Oklahoma City. RESULTS: An analysis of 534 autopsy reports revealed presence of cardiovascular abnormalities in 234 pilots (prevalence rate 43.82%). Coronary artery stenosis had a prevalence rate of 37.64%. There were 41 pilots who had evidence of severe atherosclerosis of the left coronary artery. This was significantly associated with stenosis of the right coronary and circumflex arteries. There was a statistically significant relation between coronary atherosclerosis and advancing age. DISCUSSION: Although the overall prevalence of coronary atherosclerosis is lower than previously reported, evidence of severe atherosclerosis was found in a relatively high percentage of pilots and may be a cause for concern. The findings have implications for aircrew health education and primary prevention programs. There is also a need for more standardized data collection.     

Toxicological findings in fatal civil aviation accidents, fiscal years 1968-1974.

Toxicological findings in 1,345 fatal general aviation accidents from fiscal year 1968 through 1974 are summarized. Methods used in examination of specimens for alcohol, drugs, carbon monoxide, cyanide, and cholinesterase activity are described. Blood ethanol levels in excess of 0.050% were found in 117 of the 1,345 pilots (8.7%). Drugs were found in 16 cases (1.2%). These and other toxicological findings indicate that in more than 40% of the cases, information worthy of consideration in developing the human-factors history of an accident or the cause of death from survivable crashes was obtained.     

美国民用航空器事故医学调查简介

20 0 0年 7月 15日作为中美双方航空医学交流的一部分 ,由民航总局飞行标准司组团 ,前往位于美国俄克拉荷马城的美国联邦航空局 (Federal AviationAdministration,FAA)和民用航空医学研究所 (Civilian Aviation Medicine Insti-tute ,CAMI)接受为期两周的“民用航空器事故医学调查 "的培训。现将有关美国航空器事故医学调查的梗概介绍如下。一、航空器事故医学调查的组织管理1.航空器事故率 :1998年美国运输发生死亡性事故 4390 2起 ,其中高速路事故占 94.2 % ,航空性事故占 2 .4% ,航海和铁路事故各占 1.7%。航空事故发生的时段分布…     

民航飞行员白内障患病率调查及航空医学鉴定

目的 调查民航飞行员白内障患病率,探讨其航空医学鉴定. 方法 收集2009年5月至2010年4月民航飞行员眼科检查资料,分析白内障患病特点和4例白内障摘除联合人工晶状体植入术后特许飞行合格飞行员的随访资料.不同年龄组飞行员白内障检出率比较采用卡方检验. 结果民航飞行员白内障检出率为0.28％,患病年龄21～67岁,不同年龄组之间白内障检出率差异有统计学意义(x2 =217.737,P＜0.01),40岁以上飞行员白内障检出率随年龄逐渐升高.晶状体混浊部位以皮质性混浊为主.4例特许飞行合格飞行员白内障摘除联合人工晶状体植入术后视功能良好,特许合格以来已累计安全飞行1300～4000 h,无空中不适及事故征候. 结论 我国民航飞行员目前白内障检出率较低,但患病率有随年龄升高的趋势.白内障飞行员出现视物模糊、视力下降、视功能受损时应临时停飞治疗,术后观察3个月,进行航空医学鉴定时若视功能良好,无影响飞行安全的并发症,可考虑特许飞行合格;特许飞行随访3～4年,若视功能稳定,特许飞行安全,无事故征候,可考虑飞行合格.     

Selective serotonin reuptake inhibitors in pilot fatalities of civil aviation accidents, 1990-2001

INTRODUCTION: Selective serotonin reuptake inhibitors (SSRIs) are popularly prescribed for treating depression. With a few exceptions, these psychotropic medications are not approved by aeromedical regulatory authorities for use by aviators. Since SSRIs have the potential for impairing performance and causing drug-drug interactions, the prevalence of SSRIs in pilot fatalities of civil aviation accidents was evaluated. METHODS: Postmortem samples from pilots involved in fatal civil aircraft accidents are submitted to the Civil Aerospace Medical Institute (CAMI) for toxicological evaluation. Findings from such evaluations are maintained in the CAMI Toxicology Database. This database was examined for the presence of SSRIs in pilot fatalities of the accidents that occurred during 1990-2001. RESULTS: Out of 4,184 fatal civil aviation accidents from which CAMI received samples, there were 61 accidents in which pilot fatalities had SSRIs. Of these accidents, 56 were of the general aviation category, 2 were of the air taxi and commuter category, 2 were of the agricultural category, and 1 was of the ultralight category. Blood concentrations of SSRIs in the fatalities were 11-1121 ng x ml(-1) for fluoxetine; 47-13102 ng x ml(-1) for sertraline; 68-1441 ng x ml(-1) for paroxetine; and 314-462 ng x ml(-1) for citalopram. In 39 of the 61 pilots, other drugs--for example, analgesics, antihistaminics, benzodiazepines, narcotic analgesics, and/or sympathomimetics--and/or ethanol were also present. As determined by the National Transportation Safety Board, the use of an SSRI [with or without other drug(s) and/or ethanol] has been a contributory factor in at least 9 of the 61 accidents. CONCLUSIONS: Numbers of SSRI-involved accidents were low, and blood SSRI concentrations in the associated pilot fatalities ranged from subtherapeutic to toxic levels. However, the interactive effects of other drug(s), ethanol, and/or even altitude hypoxia in producing adverse effects in the pilots cannot be ruled out. Findings from this study should be useful in investigating SSRI and other substance-involved accidents and in making decisions concerning the use of SSRIs in aviation.     

Current role of alcohol as a factor in civil aircraft accidents.

Ethyl alcohol continues as a serious adverse factor in general aviation flight safety. According to FAA figures, the level of alcohol-associated general aviation fatal accidents has remained relatively static at a 16% general level since 1969. A recent survey of the attitudes of pilots toward alcohol and flying reveals a lack of appreciation among one-third of the pilots concerning the adverse effects of alcohol on safe flight. A renewed pilot education program on alcohol and flight safety appears indicated.     

First-generation H1 antihistamines found in pilot fatalities of civil aviation accidents, 1990-2005

INTRODUCTION: First-generation H1-receptor antagonists are popularly used for alleviating allergy and cold symptoms, but these antihistaminics cause drowsiness and sedation. Such side effects could impair performance and, thus, could be the cause or a factor in accidents. Therefore, the prevalence of these antagonists was evaluated in aviation accident pilot fatalities. METHODS: The Civil Aerospace Medical Institute's (CAMI's) Toxicology Database was examined for the presence of the first-generation antihistamines in pilot fatalities of civil aircraft accidents that occurred during a 16-yr (1990-2005) period. RESULTS: Of 5383 fatal aviation accidents from which CAMI received specimens, there were 338 accidents wherein pilot fatalities (cases) were found to contain brompheniramine, chlorpheniramine, diphenhydramine, doxylamine, pheniramine, phenyltoloxamine, promethazine, and triprolidine. Of the 338 accidents, 304 were general aviation accidents, and 175 of the 338 pilots held private pilot airman certificates. Antihistamines were detected alone in 103 fatalities (1 antihistamine in 94 and 2 antihistamines in 9), while other drug(s) and/or ethanol were also present in an additional 235 fatalities. The antihistamines were found in approximately 4 and 11% of the fatalities/accidents in 1990 and in 2004, respectively. The use of antihistamine(s) was determined by the National Transportation Safety Board to be the cause of 13 and a factor in 50 of the 338 accidents. CONCLUSIONS: There was an overall increasing trend in the use of antihistamines by aviators during the 16-yr span. Blood levels of the antihistaminics were in the sub-therapeutic to toxic range. Findings from this study will be useful in investigating future accidents involving antihistamines.     

Hypnosis in the investigation of aviation accidents

The efficacy of hypnotic inquiry techniques with ten witnesses to six recent Naval aircraft accidents was evaluated in this study. Eight witnesses had been directly involved in an accident, five as mishap pilots. Interviews were conducted under conservative standards of practice after regular interviews had been completed and all depositions taken. Naval officers who accompanied the witness(es) to the interviews and concomitantly assisted the accident investigation boards served as the evaluators. Important information concerning the accidents was gained in the majority of the interviews. Secondary survival information of importance was obtained in a number of cases as well. None of the witnesses experienced psychological or career problems as a result of the interviews, and the hypnosis seemed highly therapeutic in some cases. Results suggest that hypnotic interview techniques with witnesses may be of great value in the investigations of certain aircraft accidents.     

The right and wrong stuff in civil aviation

Aircrewmembers (ACMs) enter a mortally hostile environment when they take off from Earth in their flying machines. Their physiological adaptation has been augmented and supported through ergonomics, avionics, and engineering, but no such technological aid helps them adapt their minds to that atypical condition. They must rely upon their own psychic resources, i.e. "aeronautical motivation" in the three levels of consciousness, and defense mechanisms to counteract their "aeronautical anxiety." Various relationships of motivation and defense give rise either to the flying adaptation syndrome or the various forms of the secondary flying disadaptation syndrome when ACMs must face the dangers of flight. These alterations of the ACMs' psychic balance may cause temporary or permanent medical disqualification due to the impairment of safety which they provoke. This paper proposes an analysis of the interplay between motivation, psychic defenses, and aviation stress to explain the manifestations of flight adaptation and disadaptation seen in some aircrewmembers.     

民航飞行人员的飞行时限与休息制度问题

目的 综述民用航空中由于飞行时间不规律,夜航,快速时区变化等对飞行人员睡眠、疲劳和工作能力的影响,提出关于民航飞行人员时限与休息制度的建议。资料来源与选择 国内外该领域的研究论文及综述。资料引用 引用国内外学术刊物上发表的论文及综述。资料综合 就导致民航飞行人员飞行疲劳的相关问题进行讨论,并在此基础上提出民航飞行人员的飞行时限与休息制度的原则。结论 制定民航飞行人员的飞行时限与休息制度必须考虑到昼     

The consequences of in-flight incapacitation in civil aviation

Aviation medical standards world-wide place much emphasis upon the cardiovascular (CV) status of the individual. This is justified, especially in the Western world, because of the high incidence of CV disorders in the population and their likely similar occurrence in the aircrew peer group. These standards do not in general require the demonstration of any objective short fall in performance, but rather guard against a potential threat, that of sudden incapacitation. However, some observers have sought to question whether or not this threat and its potential consequences is as great as it might appear and to quantify the risks. We have now carried out and analysed over 1,300 closely observed simulator exercises, using two protocols, in which sudden and subtle incapacitation has been programmed to occur to the handling pilot at a critical phase of flight. The results have been assembled and extrapolated with the recorded incidence of sudden incapacitation in flight in civil airline operations so the actual degree of risk can be identified. Conclusions can be drawn from this on the relevance of present cardiovascular standards and suggestions for improvement are made.     

Fear of flying in civil aviation personnel.

Included in a multi-faceted questionnaire concerning the work environment within a commercial airline were questions on flight anxiety and exposure for critical incidents. A total of 1,147 respondents were included in the sample. Results show that 9.2% of the aircrew members feel anxious or afraid of flying monthly or more often. The cockpit crewmembers were less anxious than the cabin crewmembers, and female cabin crewmembers were more anxious than male. Aircrew who had experienced critical situations and had not sufficiently worked through their experiences, reported more anxiety than those with adequate work-through. We recommend that the cabin crewmembers be provided with better information on how the flight deck operates, and that more stable work crews and co-training of cabin and cockpit crewmembers be facilitated. A formal debriefing routine after critical incidents is advised. Personnel with flight anxiety should be offered help to reduce their fear level.     

民航飞行员能量消耗与总能量代谢的研究

采用Douglas－Haldane气体代谢法、膳食调查及生活作业追踪法，对67名民航飞行员的基础代谢率（BMR）、安静代谢率（RMR）、飞行作业能量消耗及全日能量代谢进行了测试。结果表明：BMR平均为2．6OkJ.m－2.min-1，RMR平均为3．10kJ．m－2.min－1，常规飞行动作能量消耗为3．49－5．57kJm－2.min－1，应急飞行作业能量消耗为8．25kJ.m－2·min－1。全日能量消耗平均为12293kJ．d－1，飞行员热能摄入量在11714一14225kJ.d－1。根据测试结果，对民航飞行员作业的劳动生理负荷进行了评价，并提出民航飞行员膳食热能需要量。     

Alcohol violations and aviation accidents: findings from the U.S. mandatory alcohol testing program

INTRODUCTION: Mandatory alcohol testing has been implemented in the U.S. aviation industry since 1995. This study documents the prevalence of alcohol violations and the association between alcohol violations and aviation accidents among aviation employees with safety-sensitive functions. METHODS: Data from the random alcohol testing and post-accident alcohol testing programs reported by major airlines to the Federal Aviation Administration for the years 1995 through 2002 were analyzed. A violation was defined as an alcohol level of > or = 0.04% or a refusal to submit to testing. Relative and attributable risks of accident involvement associated with alcohol violations were estimated using the case-control method. RESULTS: During the study period, random alcohol testing yielded a total of 440 violations, with an overall prevalence rate of 0.09% and a prevalence rate of 0.03% for flight crews. Alcohol violations were associated with an increased yet not statistically significant risk of accident involvement (odds ratio 2.56, 95% confidence interval 0.81-7.08) and were attributed to 0.13% of aviation accidents. DISCUSSION: Alcohol violations among U.S. major airline employees with safety-sensitive functions are rare and play a negligible role in aviation accidents.