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Biomedical subjects

L Quan

Publications and source records attributed to L Quan.

At least 19 recordsLinked to original sources

Characteristics of drowning by different age groups.

CONTEXT: While it is known that the risk of unintentional drowning varies with age, the manner in which drowning episode characteristics vary by age has not been well described. Such information might be useful for prevention. OBJECTIVE: To describe characteristics of drowning by age group. DESIGN: Retrospective review of the characteristics of drowning victims and their drowning incidents obtained from death certificates, medical examiner, pre-hospital, emergency department, and hospital records. SETTING: Three counties in Western Washington state. SUBJECTS: Residents who died (n=709) of unintentional drowning within the study region during 1980 through 1995. OUTCOMES: Age specific counts, proportions, and rates per million person years were estimated for and compared among six age groups. RESULTS: Rates varied by age group: 0-4 (30.5), 5-14 (11.6), 15-19 (29.9), 20-34 (21.5), 35-64 (12.5), and 65 years or older (21.2). Among those 0-4 years, the proportions that drowned in pools, bathtubs, and open water were nearly equal. But from age 5-64 years, over 69% of deaths were in open water. Among those 65 years and older, the deaths were almost evenly divided between bathtub and open water; bathtub drowning rates were highest in this age group, 10.9. Pre-drowning activities were divided into boating, swimming, car passenger, bathing, and fell in while doing something else. Most (64/89, 76%) victims aged 0-4 years drowned while bathing or after falling in. Among those 15-19 years, most occurred while swimming (24/79, 34%) or boating (22/79, 31%). The drowning event was least often witnessed among those 0-4 years (10/36, 28%), and most often witnessed (44/58, 76%) among those 15-19 years. Medical care (pre-hospital, emergency department, or hospital) was most often involved in drownings of those 0-4 years (70/89, 79%) and least among those over 65 years (11/86, 13%). CONCLUSION: The characteristics of drowning episodes vary greatly by age. Different prevention strategies may be needed for different age groups.

Adolescent↗

Sudden death of an infant with 'an early epileptic encephalopathy'.

This article reports an autopsy case of sudden death of an infant with an infrequent encephalopathy involving epileptic episodes. The infant was a 1-year and 10-month-old boy, who had a history of the first convulsive seizures in the third month after birth. The clinical diagnosis was described as 'an early infantile epileptic encephalopathy with suppression-bursts' (Ohtahara syndrome). On a winter day, he was collapsed following a high fever and was already dead on the arrival at a hospital. The body was small for the age and poorly nourished. The autopsy and postmortem magnetic resonance imaging scan (MRI) of formalin-fixed brain revealed advanced unsymmetric brain atrophy with cortical dysplasia, which were prominent in the left temporal and right occipital lobes, and sclerotic atrophy of the parahippocampal gyri, additionally showing a feature of the olivo-ponto-cerebellar atrophy. However, the cause of death was pathologically and microbiologically determined as bacterial bronchopneumonia following pulmonary infection of the influenza A virus. In sudden death cases of physically handicapped infants, the investigation of viral infection in consideration of an epidemiological survey is important even when the death can be pathomorphologically explained.

Brain↗

Immunohistochemical investigation of pulmonary surfactant-associated protein A in fatal poisoning.

To evaluate the immunohistochemical distribution of pulmonary surfactant-associated protein A (SP-A) in fatal poisoning in relation to the effects of drugs and poisons on respiratory function, 42 forensic autopsy cases were examined by scoring the staining intensity. The highest scores of SP-A staining, with dense granular deposits (aggregates) in the intra-alveolar space, were observed in fatalities from pancuronium bromide (muscle relaxant) injection and petroleum (butane) gas inhalation. Poisoning with organophosphate pesticides and arsenic (ingestion) showed a second grade SP-A score. However, The SP-A scores were relatively low in ethanol and sedative-hypnotic intoxication. Carbon monoxide intoxication showed a varied degree of SP-A score, and the aggregated SP-A score tended to be higher in cases of lower blood carboxyhemoglobin concentration. A varied SP-A score was also observed in methamphetamine fatalities, in which the score was relatively low in cases with a higher serum drug level. Increase of SP-A was not always associated with the intra-alveolar effusion or hemorrhages. The above-described observations suggested that the immunohistochemical score of SP-A may be a possible indication for intensity and duration of drug/poison-dependent respiratory distress.

Adolescent↗

Fatal traumatic rupture of an aortic aneurysm of the sinus of Valsalva: an autopsy case.

This report describes an autopsy case of a rare type of aortic sinus of Valsalva aneurysm, which caused fatal rupture from a blunt chest impact. A 51-year-old male was hit in the chest with a fist, lost consciousness after about 15min and died after approximately 7h. The postmortem examination revealed a large saccular aneurysm of the right coronary sinus bulging on the right atrium, which had a full laceration causing pericardial hematoma (cardiac tamponade). A related chest wall injury was observed in the right outer mammary region. A rare type of bulging onto the right atrium and subsequent sclerosis of the right coronary artery appeared to have greatly contributed to the fatal rupture.

Aortic Rupture↗

Post-mortem urinary myoglobin levels with reference to the causes of death.

To evaluate pathophysiological significance of post-mortem urinary myoglobin levels in determining the cause of death, we investigated 210 forensic autopsy cases, partially in comparison with serum levels. Post-mortem serum myoglobin levels were extraordinary high in most cases possibly due to post-mortem change. Urinary myoglobin levels did not correlate with the serum levels, showing possible post-mortem elevation in cases of a prolonged post-mortem period over 48h. A high (>1000 ng/ml), moderate (100-1000 ng/ml), slight (50-100 ng/ml) and not significant (<50 ng/ml) elevation of urinary myoglobin were observed in 26, 43, 31 and 110 cases, respectively. Half the highly elevated cases were those with a survival time over 24h. In cases of minor muscle injury such as head trauma, elevation of urinary myoglobin level was closely related to longer survival. In acute/subacute deaths with a post-mortem interval within 48h, a significant difference was observed in relation to the blood carboxyhemoglobin (COHb) levels of fire victims: myoglobinuria over 100 ng/ml was more frequently and markedly observed in cases with COHb below 60% than over 60%, suggesting muscle damage in fatal burns. Similar elevation was observed in heat stroke victims, and also in some cases of acute and subacute death from polytrauma, asphyxiation, drowning, electricity and spontaneous cerebral bleeding, but not in myocardial infarction. Thus, it was suggested that high post-mortem urinary myoglobin levels in acute and subacute death cases may be a possible indicator of antemortem massive skeletal muscle damage as well as exertional muscle hyperactivity or convulsive disorders associated with hypoxia.

Adolescent↗

Intranuclear ubiquitin immunoreactivity in the pigmented neurons of the substantia nigra in fire fatalities.

To evaluate the significance of immunohistochemical staining of ubiquitin (heat shock protein) in the midbrain for medico-legal investigation of death in fires, we examined forensic autopsy cases of fire fatalities (n = 35) in comparison with controls (n = 27; brain stem injury, acute myocardial infarction and carbon monoxide poisoning other than fire fatality). There were two intranuclear staining patterns in the nuclei of pigmented substantia nigra neurons: a type of inclusion (possible Marinesco bodies) and a diffuse staining. Percentage of nuclear ubiquitin positivity (Ub-positive %) in fire fatalities (2.7-44.7%; mean, 18.5%) was significantly higher than in brain stem injury (n = 9; 0-10.4%; mean, 4.5%) and myocardial infarction (n = 14; 1.5-14.6%; mean, 6.9%), independently of blood carboxyhemoglobin (COHb) levels. Age-dependent increase in Ub-positive % was observed in lower COHb (< 60%) cases. The intranuclear diffuse ubiquitin staining was not observed in cases of high blood cyanide level (> 1.0 microg/ml). These observations showed that intranuclear ubiquitin immunoreactivity of the pigmented substantia nigra neurons in the midbrain was induced by severe stress in fires.

Aged↗

Intranuclear ubiquitin immunoreactivity of the pigmented neurons of the substantia nigra in fatal acute mechanical asphyxiation and drowning.

To evaluate the significance of immunohistochemical staining of ubiquitin (heat shock protein) in the midbrain for the medico-legal diagnosis of fatal asphyxiation and drowning, we investigated forensic autopsy cases of fatal mechanical asphyxia (n = 18), manual/ligature strangulation (n = 9), hanging (n = 4), aspiration/choking (n = 5) and drowning (n = 16). These were compared to control groups (n = 30) consisting of fatalities from brainstem injury (n = 12) and acute myocardial infarction (n = 18). Ubiquitin was clearly demonstrated in the nuclei of pigmented substantia nigra neurons, showing two intranuclear staining patterns: a type of inclusion (possibly Marinesco bodies) and a diffuse staining. The diffuse staining was significantly more frequently observed in cases of drowning. The percentage of total ubiquitin positive neurons was frequently higher in strangulation (5.1-28.4%, mean 17.0%), aspiration/choking (5.3-32.0%, mean 17.6%) and drowning (7.0-34.1%, mean 19.8%), but relatively low in hanging (5.1-12.7%, mean 8.6%), brainstem injury (0-10.4%, mean 5.0%) and acute myocardial infarction (1.5-16.9%, mean 8.3%). These observations suggest that intranuclear ubiquitin immunoreactivity of the pigmented substantia nigra neurons in the midbrain was induced by a fatal severe stress on the central nervous system in asphyxiation and drowning.

Adult↗

Immunohistochemical investigation of pulmonary surfactant-associated protein A in fire victims.

To evaluate the forensic pathological significance of the immunohistochemical distribution of pulmonary surfactant-associated protein A (SP-A) in determining the cause of death in fires, 57 fire victims were examined by scoring the staining intensity. The highest SP-A score with dense granular deposits (aggregates) in the intra-alveolar space was frequently observed in cases with a lower blood carboxyhemoglobin (COHb) level (<60%). The SP-A score was relatively low in carbon monoxide intoxication due to causes other than fires. High SP-A scores showed a relation to the serum level and in part related to the bloody exudate in the lower airway. These observations suggested that the increase in SP-A in fire victims may be mainly related to pulmonary alveolar injury due to the inhalation of hot air and/or irritant gases rather than hypoxia.

Journal Article↗

Immunohistochemistry of pulmonary surfactant-associated protein A in acute respiratory distress syndrome.

Acute respiratory distress syndrome (ARDS) is a fatal complication in severe traumas and diseases. Although the contribution of pulmonary surfactant abnormality to the pathogenesis of ARDS has been clinically fairly well investigated, the histopathological evidence has not been established. The aim of this study was to clarify the immunohistochemical distribution of surfactant-associated protein A (SP-A) for early diagnosis of ARDS with special regard to hyaline membrane (HM) formation. Two-hundred-and-ten autopsy cases of prolonged death from various traumas and diseases were investigated. ARDS were observed in 23 cases, showing speckled SP-A immunostaining. During the early, exudative phase of ARDS, characteristic SP-A distribution showed intense staining in the intra-alveolar massive aggregates and thick 'peeling'-like substances accompanied with a lot of granular staining. During the proliferative phase, localized accumulation of granular SP-A and macrophages containing dense granular SP-A became predominant. During the final fibrotic phase, SP-A staining in HMs became weak, and disseminated granular staining was observed in the alveolar spaces. These findings provide morphological evidence of the increase of SP-A during the early phase of ARDS, including some molecular alteration and its decrease during the late phase. Characteristic SP-A distribution in the exudative phase appeared to be especially useful for early histopathological diagnosis of respiratory distress, even prior to the appearance of typical HMs.

Journal Article↗

Do parents value drowning prevention information at discharge from the emergency department?

STUDY OBJECTIVE: We determined parent recall and perceived usefulness of drowning prevention messages included in routine computer-generated discharge instructions. METHODS: All pediatric emergency department patients' computerized discharge instructions included 3 prevention messages: wear a life vest, swim in safe areas, and do not drink alcohol while swimming or boating. Parents were telephoned 1 to 2 weeks after the visit and asked to recall the prevention messages and rate the usefulness of the instructions. Responses were linked with patient characteristics and ED visit variables (day and time of visit, duration of ED visit, severity of condition, diagnostic category, number of tests, and treatments). RESULTS: Of 914 parents who were contacted, 795 were eligible. Of those, 619 (78%) completed the interview. Fifty percent of parents recalled receiving drowning prevention information; of these, 41% recalled unaided the life vest messages and 35% of 155 parents who did not own a life vest stated they would subsequently consider buying their child a life vest. Most (88%) rated the prevention information useful or very useful. No patient or visit variables were associated with usefulness ratings. CONCLUSION: Written injury prevention messages with discharge instructions were well received by parents of children in a pediatric ED. The ED may be a setting where families could receive injury prevention education.

Chi-Square Distribution↗

Cervical spine injuries among submersion victims.

BACKGROUND: Submersion victims are frequently considered at high risk for cervical spine (C-spine) injury regardless of whether they sustain a traumatic injury. We hypothesized that C-spine injury is unlikely in submersion victims who do not sustain high-impact injuries. METHODS: The study was a cohort study of all people who submerged between January 1974 and July 1996 and received medical care or were seen by the medical examiner in King, Pierce, and Snohomish counties in Washington State. RESULTS: Eleven (0.5%) of 2,244 submersion victims had C-spine injuries. All 11 had submerged in open bodies of water; had clinical signs of serious injury; and had a history of diving, motorized vehicle crash, or fall from height. No C-spine injuries occurred in 880 low-impact submersions. CONCLUSION: Submersion victims are at risk for C-spine injury only if they have also sustained a traumatic injury. Routine C-spine immobilization does not appear to be warranted solely on the basis of a history of submersion.

Adolescent↗

Use of Washington State newspapers for submersion injury surveillance.

OBJECTIVES: To evaluate the usefulness of newspapers as a surveillance tool for submersion injury, the proportion of submersion events and important details reported in Washington State newspapers was determined. It was also determined whether a letter sent to newspaper editors to encourage reporting changed the proportion and content of reported submersion events. METHODS: Newspaper articles regarding submersion were collected from 225 Washington newspapers from June 1993 through September 1998. Newspaper articles were linked to computerized state death and hospital records. Reporting during periods before and after a letter was sent encouraging more newspaper articles on submersion injury and preventative factors was compared. RESULTS: A total of 1,874 submersion victims were identified in the three data sources. Of the 983 victims who had a death certificate, 52% were reported in at least one news article. Of the 471 persons in hospital discharge data, 25% were reported in a newspaper. Reporting of pediatric victims who died increased from 63% to 79% (p=0.008); reporting of hospitalized persons increased from 23% to 27% (p=0.3). There were increases in reporting of swimming ability (7% to 15%, p<0.001), supervision (82% to 91%, p<0.001), and alcohol use (7% to 24%, p<0.001). Reporting of life vest use decreased (35% to 23%, p<0.001). CONCLUSIONS: Newspapers failed to report about one half of fatal submersions and three quarters of submersions that resulted in a hospitalization. An effort to improve reporting was associated with an increase in the proportion of pediatric drownings that were reported, but a consistent improvement in content was found. The usefulness of newspaper articles as a surveillance tool may be limited.

Adolescent↗

Evaluation of resuscitation skills in new residents before and after pediatric advanced life support course.

OBJECTIVE: Acquisition of resuscitation skills taught in advanced resuscitation courses has not been evaluated. We sought to determine the interobserver reliability of a resuscitation performance skills checklist to assess resident performance of bag mask ventilation, intubation, defibrillation, and intraosseous vascular access, and to measure skill acquisition by entering residents after a pediatric advanced life support (PALS) course. DESIGN: The resuscitation skills of all 39 pediatric R1's in 2 university-based training programs were assessed immediately before and after completion of a PALS course just before starting residency. Independent observers scored and timed resident performance of bag mask ventilation, endotracheal intubation, intraosseous access, and defibrillation. Scores before and after the PALS course were compared. Four independent observers scored 4 residents' videotaped skills performance. Observers' scores for each resident were compared. RESULTS: Successful performance improved for bag mask ventilation from 62% to 97% after the PALS course; for successful endotracheal intubation, from 64% to 90%; for successful intraosseous needle placement, from 54% to 92%; and for successful defibrillation, from 77% to 97%. Interobserver reliability was high for continuous and noncontinuous variables. CONCLUSIONS: New residents demonstrated significant acquisition of pediatric resuscitation skills immediately after completion of the PALS course. The skills performance checklist has excellent interobserver reliability and is a useful tool for evaluation of other training venues.

Clinical Competence↗

[Radiographic examination of skeletalized remains of an abandoned infant: a case report with special reference to odontological findings].

A homeless couple confessed that they had buried their baby, who died at the age of three months, in the graveyard two years earlier. The recovered infantile remains had been already completely skeletonized and dismembered. However, the maxilla and mandibula of the average matured infants, the age of the body was estimated to be 1 to 2.5 months old on the basis of the degree of calcification of deciduous teeth.

Age Determination by Teeth↗

Child and elderly victims in forensic autopsy during a recent 5 year period in the southern half of Osaka city and surrounding areas.

To outline the recent features of child and elderly victims from the medico-legal perspective with special reference to abuse and neglect, a retrospective investigation of forensic autopsy cases over a 5 year period (1994-1998) in the southern half of Osaka city and surrounding areas (a population of 1.57 million) was undertaken. Among 646 autopsy cases, there were 53 child cases (under the age of 15 years, about 80% below 6) and 121 elderly cases (65 years old and above). Nearly half of the child deaths and more than half of the elderly deaths were described as accidental. Fire and traffic victims were much more frequent in the elderly. Child victims included those of neonaticide/infanticide (n=6), physical abuse (n=10), unintentional fatal infliction (n=2), neglect (n=2), mutual suicide (n=2), suicide (n=1) and murder (n=3). Child abuse and neglect were domestic maltreatment by the parents. In this series, there was a comparable number of fatalities due to maltreatment in the elderly (n=13) and in children, and non-domestic violence was more frequent in the elderly than domestic violence. Elderly females tended to be battered by their sons or grandsons in domestic violence cases, whereas males were predominantly attacked by younger males in non-domestic violence. The other elderly victims included those of self-neglect (n=2), murder (n=7) and suicide (n=9). Non-domestic homicide of the elderly occurred mainly in the center of the city, whereas domestic maltreatment of children and the elderly was sporadic, although somewhat more frequent in the peripheral zone of the city and the surrounding areas. The above profile of child and elderly abuse suggests a substantial influence of social and familial backgrounds.

Accidents↗

Automated determination of carboxyhemoglobin contents in autopsy materials using head-space gas chromatography/mass spectrometry.

To establish a method for the routine analysis of carboxyhemoglobin (COHb) in autopsy materials including those which have undergone postmortem changes, e.g. thermo-coagulation, putrifaction and contamination, an automated head-space gas chromatography/mass spectrometry (GC/MS) analysis was utilized. The procedure consisted of preparation of the sample in a vial and a carbon monoxide (CO) saturated sample, for estimation of hemoglobin content, in another vial, the addition of n-octanol, potassium ferricyanide and an internal standard (t-butanol), GC separation and determination of CO using a GC/MS system equipped with an automated head-space gas sampler. The method was practical not only with the blood and bone marrow aspirates to confirm the findings on the CO-oximeter system, but also with the thermo-coagulated and putrified blood.

Automation↗