Patricia J. McFeeley

Hantavirus pulmonary syndrome in the United States: A pathological description of a disease caused by a new agent

An outbreak of an acute respiratory disease in the southwestern United States has led to the recognition of a new hantaviral illness. This report describes a unique spectrum of antemortem and postmortem pathological findings seen in a case series of nine surviving patients and 13 who died. Clinical, laboratory, and autopsy findings were derived from a consecutive series of individuals confirmed to have hantavirus pulmonary syndrome. Laboratory studies included chemical, hematological, and bone marrow analyses as well as flow cytometric and immunohistochemical phenotyping. Autopsy tissues were examined by routine histological stains, immunohistochemical methods, and transmission electron microscopy. The lung is the primary target organ in this illness. Pulmonary abnormalities include pleural effusions, alveolar edema and fibrin, and an interstitial mononuclear cell infiltrate. Large immunoblast type cells are seen in the lungs, blood, bone marrow, lymph nodes, liver, and spleen. A tetrad of hematological findings includes left-shifted neutrophilic leukocytosis, thrombocytopenia, hemoconcentration in severe cases, and circulating immunoblasts. In contrast to previously described nephropathic hantaviral syndromes, hantavirus pulmonary syndrome is characterized by a unique constellation of pulmonary, hematological, and reticuloendothelial pathological findings. The pulmonary findings are distinguishable from fatal adult respiratory distress syndrome. The data suggest a capillary leak syndrome restricted to the pulmonary circulation. Likewise, the hematological picture is unique and may be valuable in the rapid identification of cases for further diagnostic studies.

Cricothyrotomy performed by prehospital personnel: A comparison of two techniques in a human cadaver model

Little is known about the proficiency of prehospital personnel when performing cricothyrotomies. The authors compared two techniques for establishing an airway through the cricothyroid membrane used by paramedic students. One technique used a prepackaged kit that consisted of a dilator that is passed percutaneously through a breakaway needle. This percutaneous device (PD) was compared with a standard surgical approach (SA) using a scalpel and endotracheal tube. Data was collected on a total of 44 paramedic students who were allowed to attempt each of the procedures. No significant difference in the success rate on the first attempt was found between the two procedures (86% for the SA and 73% for the PD; P = .186). The surgical approach was significantly faster (46 +/- 17 seconds v 103 +/- 62 seconds; P < .01). It was also judged to be significantly easier to perform when evaluated on a linear analog scale (SA, 2.6 +/- 2.0 v PD, 5.1 +/- 2.8; P < .001). Because some procedures were performed on cadavers whose cricothyroid membranes had already been violated, the procedures performed on intact membranes only were also analyzed. Similar, statistically significant differences for insertion time and ease of insertion were again found. Prehospital personnel can be trained to perform cricothyrotomies with a reasonable degree of proficiency. A traditional surgical approach, however, may be faster and less difficult to perform than a comparable procedure using a commercially available percutaneous device.

Increased pedestrian mortality among the elderly

Elderly pedestrians struck by motor vehicles have the highest mortality rate of all pedestrian injury victims. One thousand eighty-two motor vehicle-pedestrian accidents occurring in a metropolitan area over a 5-year period were studied. Age-specific injury rates and fatality rates were evaluated with respect to the injury severity scores (ISS) for all fatally injured autopsied pedestrians. Of the 1,082 injuries, 131 fatalities occurred. Mean ISSs were found to be significantly higher for pedestrians dying at the scene of the accident (mean ISS, 54.83) and higher for those dying in the emergency department (mean ISS, 45.18), than for pedestrians who died in the hospital (mean ISS, 30.57) (P less than .0001). The mortality rate for pedestrians aged greater than or equal to 60 years was substantially higher than for those adults aged less than 60 years of age (P less than .001). Elderly patients involved in accidents were much more likely to die than younger pedestrians (44.6% v 10.4%; P less than .0001). Elderly pedestrians were significantly overrepresented in the group of pedestrians dying in the hospital compared with younger injury victims (52.5% v 21.5%; P less than .008). This study shows that elderly pedestrians struck by motor vehicles die at a higher rate because they succumb to injuries in the hospital more frequently than younger pedestrians. This may reflect the greater susceptibility of the elderly to metabolic, surgical, and infectious complications after admission to the hospital. A decrease in mortality rates of elderly patients suffering pedestrian injuries will probably follow improved in-hospital intensive care services for the elderly.

Traumatic asphyxia in New Mexico: A five-year experience

Compression of the chest causing facial petechiae, violaceous facial hue, subconjunctival hemorrhages, and frequent mental status abnormalities has been termed traumatic asphyxia. We identified 35 such cases occurring in the State of New Mexico from 1980 to 1985 from records of the Office of the Medical Investigator (n = 30) and from cases presenting to the University of New Mexico Trauma Center (n = 5). Among those found at highest risk for traumatic asphyxia were people ejected from motor vehicles, men working under cars that were inadequately supported and fell onto the victims, children under the age of 5 years who were crushed under household furniture, and people involved in construction activities. Traumatic asphyxia following a moving motor vehicle accident was significantly associated with alcohol ingestion (p less than 0.001). Preventive and therapeutic strategies should focus on the groups and events identified.

Motorcycle fatalities in New Mexico: The association of helmet nonuse with alcohol intoxication

STUDY OBJECTIVE To determine the relationship among helmet use, alcohol use, and ethnicity in people killed on motorcycles. DESIGN Retrospective review of all motorcycle fatalities in New Mexico from 1984 through 1988. SETTING Office of the Medical Investigator, State of New Mexico. TYPE OF PARTICIPANTS All decedents of motorcycle crashes in New Mexico from 1984 through 1988. INTERVENTIONS Review of all autopsies, medical investigator reports, traffic fatality reports, and toxicological studies on fatally injured motorcyclists. RESULTS Nine of the helmeted drivers (18%) were legally intoxicated compared with 67 of the nonhelmeted drivers (51%) (chi 2 = 15.7, P less than .0001); 42 of the white nonHispanic decedents (37%), ten of Hispanic decedents (12%), and none of the Native-American decedents were wearing helmets. The head and neck region was the most severely injured body region in 42 of the nonhelmeted cases (84%) and in eight of the helmeted cases (50%) (Fishers exact test, P less than .02). CONCLUSION There is an association between nonuse of helmets and alcohol intoxication in fatally injured motorcyclists in New Mexico. Strategies for preventing motorcycle fatalities should address alcohol abuse and ethnicity in conjunction with helmet use.

Accidental firearm fatalities among New Mexico children.

STUDY HYPOTHESIS Risk factors associated with unintentional gunshot fatalities among children include gender and race of the decedent, type of firearm used, and whether loaded guns are stored within the home. STUDY POPULATION All New Mexico children 0 to 14 years old unintentionally killed by a firearm between 1984 and 1988. METHODS The New Mexico Office of the Medical Investigator master mortality file was reviewed retrospectively to identify all unintentional firearm fatalities occurring in New Mexico children during a five-year period. Medical investigator, autopsy, and police reports were analyzed to identify epidemiologic factors associated with these deaths. Chi-square and Fishers exact tests were used to analyze the data. RESULTS Twenty-five unintentional firearm fatalities were identified. These deaths occurred most frequently among children playing with loaded firearms found within the home. A disproportionate number involved handguns. CONCLUSIONS The study results provide a basis for preventive strategies that limit accessibility or decrease lethality of loaded firearms within the home.

The Spectrum of Neuropathologic Findings in Deaths Associated with Seizure Disorders

The pathologic and neuropathologic findings in 90 autopsied cases of death associated with a seizure disorder or complication thereof were reviewed. Most (69%) of the deceased individuals were between 21 and 40 years of age; two thirds were male. In 58% of patients, no cause of death other than seizure disorder was found. The ultimate cause of death in those patients was assumed to be a cardiac arrhythmia or respiratory arrest. Drowning accounted for 19% of deaths, and 17% of patients died of other contributory causes such as suicide, exposure, or atherosclerotic coronary vascular disease. Aspiration was found in the remaining 6%. Tongue lacerations or bite marks were observed in only one third of cases. The brain was normal in approximately two thirds of cases, with no focus for the origination of seizure found on neuropathologic examination. In the remainder of cases, a variety of lesions was found, with cavitary lesions, contusions, and dural lesions being the most common ones.

Rare electrocution due to powerline contact in a hot-air balloon: comparison with fatalities from blunt trauma

Powerline contact by hot-air balloons is one of the most frequent concurrences in balloon accidents resulting in injury or death. Injuries and deaths are usually a result of blunt trauma from falls. In this report, we describe the aircraft, the circumstances of the accidents and the autopsy data in two powerline contact accidents involving three deaths, one from electrocution and two, from blunt trauma sustained in falls. Appropriate pilot behavior is briefly discussed.

The investigation of alleged insecticide toxicity: a case involving chlordane exposure, multiple sclerosis, and peripheral neuropathy.

A man with no previous medical problems had two documented exposures to an insecticide containing the organophosphorous compounds chlordane and heptachlor. Six months to one year later, he began to experience neurological symptoms which progressed until his death. At autopsy, his brain showed classic findings of multiple sclerosis, and he had a severe peripheral neuropathy. Review of the literature indicates that the findings are not compatible with chlordane toxicity. Some of the factors to be used in determining the casual relationship between toxic exposure and disease processes are discussed.

Medicolegal Aspects of Necrotizing Fasciitis of the Neck

Necrotizing fasciitis of the neck (NFN) is a relatively rare, fulminating infectious process of the cervicofacial tissues which may cause sudden and unexpected death. Although often the result of a dental infection, injuries of the soft tissues of the neck may also initiate rampant cellulitis, and recognition of the underlying etiology of such cases is necessary to determine properly the manner of death. Five cases of NFN are presented with a review of the causative factors and usual bacteriology, and specific factors of medicolegal interest are addressed.