Designing the death out of balloons.
Explore the source record for details and available documents.
Airway Obstruction↗
Biomedical subjects
S P Baker
Publications and source records attributed to S P Baker.
Triple therapy in cadaveric renal transplantation: role of induction cyclosporine and targeted levels to avoid rejection.
The updated data on 61 consecutive cadaveric transplants performed at our institution from 1987 to 1990 (followup 31 to 82 months, median 54 months) were analyzed with emphasis on cyclosporine monitoring and long-term results. All patients received triple therapy with cyclosporine induction, azathioprine and prednisone regardless of graft function, and they were preferentially placed on the calcium blocker nifedipine. We monitored 12-hour cyclosporine trough levels in whole blood using high performance liquid chromatography and the dose was adjusted to maintain levels at 150 ng./ml. or greater for the first 3 months. In 17 of 61 patients (28%) 22 rejection episodes occurred and 20 nephrotoxicity episodes occurred in 17 of 61 patients (28%). There was no significant difference in the mean cyclosporine levels among 32 rejection, nonrejection, nephrotoxic and nonnephrotoxic cases at any interval. Rejection occurred by 1 month in 13 (76%) and by 3 months in 15 (88%) of 17 patients. Comparisons were made in the first month to define the desirable cyclosporine levels by calculating the mean cyclosporine only within 10 to 14 days of rejection or nephrotoxicity events. The mean cyclosporine level before rejection was significantly lower than that for nephrotoxicity (188 +/- 113 versus 304 +/- 62 ng./ml., p < 0.01). The median cyclosporine level for first month rejection was also significantly lower than that for nonrejection (156 versus 218 ng./ml., p < 0.05) and it was significantly greater for nephrotoxicity versus nonnephrotoxicity (272 versus 218 ng./ml., p < 0.05). Of 13 rejections in the first month 10 (77%) were associated with mean levels of less than 210 ng./ml. Actuarial graft survival at 1, 3 and 5 years was 93.4%, 87.8% and 78.5%, respectively. The 3-year graft survival was significantly worse for patients who experienced acute rejection episodes versus those who did not (68.8% versus 96.7%, p < 0.05) but it was not different for nephrotoxic versus nonnephrotoxic groups (85.6% versus 79.6%). Long-term function was not influenced by the occurrence of acute nephrotoxicity events. These findings confirm the efficacy of triple therapy with induction cyclosporine in cadaveric transplantation, yielding improved short-term and intermediate graft survival without any adverse effects on long-term graft function. Specific cyclosporine level monitoring is invaluable, particularly initially, with high target levels of 200 ng./ml. or greater. The use of calcium blockers may have allowed higher cyclosporine dosing in the first 3 months, mitigating against cyclosporine associated chronic nephrotoxicity.
Actuarial Analysis↗
International comparisons of injury mortality in the elderly: issues and differences between New Zealand and the United States.
BACKGROUND: International comparisons of mortality rates for injury, as for other conditions, can suggest priorities for further research and intervention. However, variability in the assignment of underlying cause, especially among the elderly, may lead to difficulty in interpreting cross-national differences in death rates. Despite similarities between the two countries, the injury death rate for ages < or = 65 in New Zealand is substantially higher than the United States rate. The objective of this study was to investigate possible reasons for this difference. METHODS: We used data not previously reported for New Zealand to calculate the cause-specific injury death rates for ages > or = 65, compared them with US rates, and examined other injury rates that could help explain the observed difference. RESULTS: The New Zealand death rate from falls for ages > or = 65 was nearly three times the US rate (92 versus 32 per 100,000), causing the death rate for all injuries in this age group to be 34% higher in New Zealand (153 versus 114 per 100,000). However, hospitalization rates for both falls and hip fractures are similar for the two countries. CONCLUSIONS: The substantially higher fall injury death rates for older New Zealanders are not fully explained by differences in the incidence of falls resulting in injury nor the case fatality rate for fall-related injury. US injury death rates based on underlying cause of death might be similar to New Zealand rates, and thus substantially higher, if subjected to comparable procedures for the completion and coding of death certificates. As in studies of other conditions, international comparisons of injury death rates based on underlying cause, especially in studies of the elderly, must consider variation between countries in death certification and coding practices.
Accidental Falls↗
Factors related to the presence of head injury in bicycle-related pediatric trauma patients.
Using data from the National Pediatric Trauma Registry, this study examined the characteristics of bicycle-related head injury, factors related to the presence of head injury, and different outcomes of head injury up to the time of discharge. Of the 2,333 patients ages 0 to 14 years who were admitted to trauma centers because of bicycle-related injury during 1989 through 1992, more than one-half (54%) sustained head injury, predominantly concussions and skull fractures. With adjustment for age, sex, and motor vehicle involvement, children who had pre-existing mental disorders, who did not wear a helmet at the time of injury, or who were injured on roads had a significantly increased likelihood of sustaining head injuries. Patients with a head injury were four times as likely as patients with no head injury to be treated in intensive care units, and were almost twice as likely to develop complications. Head injury was associated with an increased risk of inhospital fatality and high prevalence rates of communication and behavior impairments at discharge. Although it is urgent to increase helmet use substantially by child bicyclists, special attention should be paid to high-risk groups, such as children with mental disorders and children who are likely to ride in traffic.
Adolescent↗
Putting "human error" into perspective.
Explore the source record for details and available documents.
Accidents, Aviation↗
Pilots involved in multiple crashes: "accident proneness" revisited.
Analysis of crashes of air taxi and commuter flights explored the controversial issue of "accident proneness." There were 20 pilots who had 2 or more crashes during 1983-88. These pilots (repeaters) and their 42 crashes were compared with 534 pilots who were each involved in a single air taxi or commuter crash during the same period (nonrepeaters). Unexpectedly, repeaters were more experienced pilots with a mean total flight time of 7016 h vs. 5321 for nonrepeaters. Repeaters did not differ from nonrepeaters in the overall proportion of crashes in which pilot performance appeared to be a major factor. Repeaters differed significantly from nonrepeaters as to flight hours during the past 90 d (mean 215 vs. 183 h) and the proportion of their crashes that occurred in Alaska (48% vs. 24%). Alaska repeaters differed from non-Alaska repeaters with regard to the proportion of crashes on takeoff (40% vs 14%) and airport conditions as a factor (50% vs. 18%). The high proportion of repeaters involved in crashes in Alaska, where environmental conditions make flying more hazardous, and the substantially greater recent flight time suggest that the intensity and amount of occupational exposure are major determinants of pilot involvement in more than one crash.
Accident Proneness↗
Factors related to pilot survival in helicopter commuter and air taxi crashes.
We examined factors related to pilot survival in 167 consecutive helicopter commuter and air taxi crashes that occurred during 1983-88. Case fatality rates and adjusted odds ratios from multivariate logistic regression models were determined using data from the National Transportation Safety Board (NTSB). During this 6-year period, 29 pilots-in-command died in 167 helicopter commuter and air taxi crashes, a case fatality rate of 17.4%. Factors significantly associated with increased risk of pilot fatality were aircraft fire [odds ratio (OR) 20.0, 95% confidence interval (CI) 4.6-86.8], not using shoulder harnesses (OR 9.2, 95% CI 2.2-37.3), and aircraft with two engines (OR 4.8, 95% CI 1.3-17.4). In addition, we present data regarding success and failure of emergency flotation devices. The results suggest that the likelihood of pilot survival in helicopter crashes could be greatly improved by preventing crash associated fires and promoting the usage of shoulder restraints.
Accidents, Aviation↗
Injuries in working mothers.
Explore the source record for details and available documents.
Accidents, Occupational↗
Substituted 1,3-dipropylxanthines as irreversible antagonists of A1 adenosine receptors.
This report describes the synthesis of 29 xanthines containing a chemoreactive chloroaryl, beta-chloroethylamino, alpha,beta-unsaturated carbonyl, bromoacetyl, 3-(fluorosulfonyl)benzoyl, or 4-(fluorosulfonyl)benzoyl group as part of an exocyclic 1-, 3-, or 8-substituent. The xanthines inhibited the binding of [3H]-8-cyclopentyl-1,3-dipropylxanthine ([3H]CPX) to the A1 adenosine receptor (A1AR) of DDT1 MF2 cells at IC50s in the low-nanomolar to low-micromolar range. Seven of the 29 analogues irreversibly inhibited the binding of [3H]CPX without changing the KD of that ligand; five were 1,3-dipropylxanthines having the following reactive groups as 8-substituents: (bromoacetamido)methyl (24), (bromoacetamido)ethyl (25), (bromoacetamido)propyl (26), [4-(fluorosulfonyl)benzamido]methyl (33) or 3-[[4-(fluorosulfonyl)benzoyl]oxy]cyclopentyl (42). Both 8-cyclopentyl-3-[3-[[4- (fluorosulfonyl)benzoyl]oxy]propyl]-1-propylxanthine (53) and 8-cyclopentyl-1,3-bis[3-[[4- (fluorosulfonyl)benzoyl]oxy]propyl]xanthine (55) inhibited [3H]CPX binding irreversibly. Five of the ligands, including 26, 33 (IC50 = 49 microM), and 53 (IC50 = 9 microM), antagonized the binding of [3H]NECA to the A2aAR of PC12 cells, but unlike binding to the A1AR, binding to the A2aAR was completely reversible. The potency of 33 (IC50 = 2 microM, 72% loss of CPX binding at 1 microM) and 53 (IC50 = 0.01 microM, 74% loss of CPX binding at 0.05 microM) and their selectivity for the A1AR suggest that those two ligands may be useful in studies of the structure and function of that receptor.
Adenosine↗
Maternal umbilicus: ultrasound window to the gravid uterus.
Transabdominal sonograms of 68 consecutive pregnant women were reviewed retrospectively. Images of fetal parts obtained through the umbilical window (UW) were compared with those obtained through the paraumbilical window (PUW) as to (1) thickness of tissue to amniotic cavity, (2) clarity of the part imaged, and (3) noise produced. The paraumbilical tissue thickness had a mean of 18 mm; the umbilical tissue thickness, a mean of 11 mm. In patients where the difference in thickness of their paraumbilical tissue and umbilical tissue was only 0 mm to 6 mm (group 1), the UW improved clarity in 10 of 34 (29%), reduced clarity in 3 of 34 (9%), and did not change clarity in 21 of 34 (62%). Improvement of images with use of the UW was not statistically significant. However, in the group of patients with the difference in tissue thickness between the paraumbilical and umbilical areas of > 6 mm (group 2), clarity was improved in 19 of 32 (60%), reduced in 2 of 32 (6%), and was unaltered in 11 of 32 (34%). In this group the image improvement with the UW was statistically significant. Images through the UW had relatively less noise. In group 1, noise was reduced in 12 of 35 (34%). The effect of the UW on noise reduction was more significant in group 2 (tissue thickness difference > 6 mm): 24 of 31 (77%) of cases.
Female↗
Alcohol in fatally injured bicyclists.
Bicycling injury results in about 580,000 emergency room visits and 900 deaths each year in the United States. Alcohol involvement in bicycling injury has not been well documented in the literature. Using data from the Fatal Accident Reporting System, blood alcohol concentrations (BACs) among fatally injured bicyclists ages 15 years or older were examined for the years 1987-1991. Of 1,711 bicyclists who were killed at age 15 or older and tested for alcohol, 32% were positive and 23% legally intoxicated. Adjusted for age, time of crash, and other variables, male decedents were 3.3 times [95% confidence interval (CI) 2.1, 5.1] as likely as female decedents to be BAC positive, and 3.9 times (95% CI 2.2, 6.8) as likely to be legally intoxicated. Decedents ages 25 to 34 and those who died from nighttime crashes also had significantly increased likelihood of being BAC positive and being legally intoxicated. Even among decedents aged 15-19, who were legally prohibited from drinking, 14% had positive BACs. Further studies are needed to confirm the causal relationship between alcohol use and bicycling injury and to better understand the factors related to drinking and biking. The role of alcohol should be seriously considered in developing strategies of bicycling injury control and prevention.
Accidents, Traffic↗
Fluoxetine and violent death in Maryland.
A retrospective Medical Examiner case review of all deaths in Maryland where either fluoxetine or tricyclic antidepressant (TCA) use was forensically detected was conducted for the time period January 1987-July 1991. Case records and toxicology reports from the Office of the Chief Medical Examiner were reviewed to determine cause and manner of death, circumstances of death, demographic information on the decedent, prior medical history of the decedent, and presence and level of either fluoxetine or TCA in various body fluids/tissues. Suicide was the manner of death most frequently associated with TCA and fluoxetine detection. Violent methods were more often associated with fluoxetine suicides than with TCA suicides (65% v. 23%, P < 0.001). Demographic characteristics of antidepressant-related deaths in Maryland were similar to those of the entire USA. Possible explanations for the results obtained include the inherent lower lethality of fluoxetine compared to the TCAs, necessitating the use of additional means to complete the act of suicide; that physicians may have switched more impulsive, high risk patients to this new agent as it became available, thus creating a selection bias for more violence-prone individuals in the fluoxetine group; or that fluoxetine may be associated with induction of violence and/or suicidal ideation. Further research examining the possible association of these agents with violent acts is warranted.
Adolescent↗
Intentional and unintentional injuries in women. An overview.
Injuries are the leading cause of death for females 1 to 34 years old, and a major source of preventable morbidity and mortality in middle-aged and elderly women. In the United States, 43,000 women die from injuries and approximately 1 million women are hospitalized for injuries annually. The leading causes of injury death in women are motor vehicle-related injuries (34%), suicide (14%), falls (14%), and homicide (12%). Injuries of particular concern include fatal and nonfatal falls in elderly women, homicides among young black women, suicides among young white women, work-related homicides among female convenience store workers, and fatal and nonfatal injuries in pregnant and nonpregnant women associated with domestic violence. Strategies to prevent most types of injuries are either known or being investigated. Increased efforts to develop, implement, and evaluate such interventions would help to reduce the toll of injuries on women's health.
Accidental Falls↗
Head injuries incurred by children and young adults during informal recreation.
To examine injuries related to playground equipment, children's vehicles, roller skates, and skateboards, 1991 data on emergency room patients younger than 25 years in the Consumer Product Safety Commission's 91 surveillance hospitals were used. Head injury was the primary diagnosis for an estimated 58,480 patients, exceeding the total number of head injuries to bicyclists younger than 25 years. The head injury rate decreased with age. The large number and high rate of head injuries in children involved in a variety of recreational activities suggests the value of multipurpose helmets.
Adolescent↗
Drinking behavior in relation to cause of death among US adults.
OBJECTIVES: Alcohol involvement is common in many fatal injuries. This study examines drinking behavior in a nationally representative sample of US adult decedents aged 25 through 64 years and its association with cause of death. METHODS: Proxy-reported information from the 1986 National Mortality Followback Survey was used to profile the decedents' usual frequency and quantity of drinking. The association of drinking behavior with underlying cause of death was assessed while adjusting for demographic characteristics. RESULTS: Of the decedents, 17% were daily drinkers, 22% usually consumed five drinks or more per occasion, and 27% were classified as heavier drinkers. Persons who died of injury drank more frequently and heavily than those who died of disease. The adjusted odds ratio of injury's being the underlying cause of death was 1.4 (95% confidence interval [CI] = 1.1, 1.8) for daily drinkers, 1.5 (95% CI = 1.1, 2.0) for those drinking five or more drinks per occasion, and 1.4 (95% CI = 1.1, 1.7) for heavier drinkers. CONCLUSIONS: Daily drinking, binge drinking, and heavier drinking were each associated with an increased likelihood of injury as the underlying cause of death. Persons who were young, male, Native American, or divorced or separated were more likely to drink frequently and heavily.
Adult↗
Prior crash and violation records of pilots in commuter and air taxi crashes: a case-control study.
With a case-control design, this study examined the relationships of crash/incident history, violation history, pilot age, flight experience, and recent flight time with the likelihood of being involved in commuter aircraft and air taxi crashes. Cases (n = 725) were pilots who had been involved in commuter aircraft or air taxi crashes during 1983-88, identified from the National Transportation Safety Board aviation crash data base. From the Federal Aviation Administration (FAA) airmen information system, 1,555 pilots were randomly selected as controls. Controls were frequently-matched with cases on medical class and calendar year. Different data bases within the FAA's airmen information system were linked to ascertain information about crash/incident and violation records in the previous 3 years, age, total flight time, and flight time in the prior 6 months. Multivariate logistic regression models were fitted to estimate odds ratios and evaluate dose-response effects, non-linear relationships, and interactions. Cases had significantly higher prevalence rates of prior crash/incident and violation records. The estimated odds ratio of being involved in a commuter aircraft or an air taxi crash was 1.7 (95% confidence interval [CI], 1.3-2.4) for crash/incident history, and 1.6 (95% CI, 1.1-2.2) for violation history. A "dose-response effect" was found with both crash/incident history and violation history, with higher odds ratios for pilots with crashes versus incidents or with more serious violations. Total flight time showed a diminishing protective effect. Either very small or very large recent flight time increased the risk of being involved in a commuter aircraft or an air taxi crash.
Accidents, Aviation↗
Epidemiology of hot-air balloon crashes in the U.S., 1984-88.
Hot-air ballooning crashes in the U.S. during 1984-88 were examined using National Transportation Safety Board reports. The 138 crashes occurred most frequently during recreational flights (51% of the total) and paid rides (28%). A total of 480 persons were involved; 6 were killed and 123 seriously injured. Pilot error contributed to 88% of the crashes, and equipment failure or malfunction to 11%. Of the six fatal crashes, five involved collision with power lines. Crashes occurring outside optimal flying times accounted for 15% of the total. Pilots with 10 h or less flight time accounted for fewer than expected crashes. All five student pilots flying solo sustained serious injuries. Suggested prevention efforts include better training in avoidance of power lines and proper handling of rapid descents; more stringent and frequent flight testing of pilots; and a longer training period before granting pilot certificates. Attention should be given to delethalizing balloon crashes and encouraging the use of protective equipment.
Accidents, Aviation↗
The cellular and physiological actions of insulin in the central nervous system.
Insulin is a peptide hormone involved in the regulation of glucose homeostasis. Its synthesis and function in the peripheral tissues have been extensively studied and well understood. In contrast, demonstration of insulin in the brain has raised questions concerning its origin and physiological significance. In spite of extensive studies, the source of insulin present in the brain has not yet been conclusively identified. Evidence exists in support of both peripheral and central origins of this hormone in the brain. Recognized physiological effects of insulin in the central nervous system (CNS) include regulation of food intake, control of glucose uptake and trophic actions on neuronal and glial cells. These actions of insulin are mediated by insulin receptor resembling closely that in peripheral tissues and coupled with tyrosine kinase signal transduction pathway. In this review we will discuss theories concerning the origin of insulin in the CNS. In addition, we will present current information on both cellular and physiological effects of this hormone in the brain.
Animals↗