Jess Frank Kraus

Incidence of traumatic spinal cord lesions

Abstract The incidence of acute spinal cord lesions was studied in the population of 18 Northern California counties for the years 1970 and 1971. Case ascertainment included the complete review of all hospital admissions in these counties as well as the review of all death certificates, autopsy protocols, and records of the State of California Departments of Health (Crippled Childrens Service), Rehabilitation, and Industrial Relations (Workmens Compensation). The average annual incidence rate was 53.4 per million population, and the case fatality rate was 48 per cent. Almost 56 per cent of the spinal cord injuries were attributed to motor vehicle crashes. Incidence rates were three times higher for males 20–24 yr of age and females 25–29 yr of age. The pattern of case fatality rates were not similar for males and females. Age-adjusted incidence rates were highest for black males and lowest for males of Asian origin. Risk of spinal cord injury was highest for divorced or separated persons or those who have never been married. The most frequent type of impairment among persons hospitalized with a spinal cord injury was quadriparesis. Functional impairment was related to the external cause of spinal cord injury. The use of hospitalized persons as a basis for enumeration of spinal cord injuries will result in a gross underestimation of actual incidence. Due to the extremely high costs for medical care of spinal cord injury survivors and the fact that over one-half of all persons who sustained a traumatic lesion to the spinal cord were injured as a result of a motor vehicle crash, any organized program to reduce the incidence of this tragic problem must focus on the reduction of motor vehicle crashes and/or the severity of injuries sustained in them.

Acute spinal-cord lesions in a pediatric population: epidemiological and clinical features

The occurrence of acute spinal-cord lesions in children has been reported to be rare, comprising from less than one to 33 per cent of all cases of spinal-cord injuries (Audic & Maury, 1969; Burke, 1971; Melzak, 1969).To our knowledge, the epidemiological features of all cases of acute spinal-cord lesions in a pediatric population have not been previously reported. The objective of this communication is, therefore, to describe the incidence and selected epidemiological and clinical features of acute spinal-cord lesions in children, aged 1 to 15 years.

Drowning in childhood and adolescence: a population-based study.

We present the results of a residence-based study of drownings among Sacramento County, California children and adolescents ages 0-19 years for the years 1974-84. Children ages 1-3 had the highest drowning rates. The majority of drownings in this group, and one-third of all drownings in the study, occurred in residential swimming pools. Males ages 15-19 had a high drowning rate as well; at least 38 per cent of drownings in that age group were alcohol-associated. The implications for preventive efforts are discussed.

The choice of weapons in firearm suicides.

We report on the firearms used in 235 suicides in Sacramento County, California, during 1983-85. Handguns were used in 69 per cent of firearm suicides--65 per cent for males, 88 per cent for females--and in all such deaths among women ages 35 and older. We tested the hypothesis that the choice of firearms by persons committing suicide at home would passively reflect the reported prevalence of firearms by type in households in the region. Handguns were used more frequently (rate ratio 2.00; 95% CI = 1.68, 2.39), and rifles and shotguns less frequently than expected.

Survival with an acute spinal-cord injury

Abstract Survival of a cohort of 619 persons who had a spinal-cord injury while resident in one of 18 Northern California counties was determined according to external cause of the injury, level of impairment, age and sex. In addition, causes of death are described and observed and expected numbers of deaths are compared. The case fatality rate was 51.7% over five six years after the spinal-cord injury. Probability of survival was lowest for those injured from motor-vehicle collisions and within this group, the chances of survival were poorest for pedestrians and those involved in multiple-vehicle crashes. Quadriplegics had the lowest survival rates. Survival rates were higher for males than for females. Mortality attributable to the spinalcord lesion was lowest in the young, increasing with age irrespective of type of external cause of the injury, severity of the spinal-cord lesion, or sex. The relative risk of death decreased with age for each of these parameters. Cardiorespiratory complications were the most frequent immediate cause of late deaths for those surviving at least 45 days post-injury.

The epidemiology of drowning in adulthood: Implications for prevention

Previous epidemiological studies of drowning in the United States have dealt primarily with children. The epidemiology and prevention of drowning in adulthood may be very different. To test this general hypothesis, we analyzed the 293 drownings occurring among Sacramento County residents 20 years of age and above during 1974 to 1985. Drowning rates were highest for men 20-29 years of age (11.5 per 100,000 population) and blacks (7.5 per 100,000 population). Swimmers, boaters, and motor vehicle occupants were most frequently represented. Alcohol use was involved in 48% of cases overall and 77% of those involving motor vehicle occupants. A history of seizure disorder was another contributing factor. Important differences do exist in drowning epidemiology between children and adults. Our results suggest that preventing drowning will be more problematic among adults than among children. The study was also used to test the sensitivity of two commonly used methods of case ascertainment for cases in Sacramento County. A manual review of coroners records had a sensitivity of 96%. A computerized review of death certificate data from the states vital statistics data base had a sensitivity of 79%. The sources and implications of these differences are discussed.

Death resulting from motor vehicle immersions: the nature of the injuries, personal and environmental contributing factors, and potential interventions

We present an epidemiologic characterization of deaths from motor vehicle immersions, based on 77 deaths in 63 motor vehicle immersions in Sacramento County, CA, during 1974-85. All persons were autopsied; all but one of the deaths were due to drowning. Average annual mortality rates per million person years were 12 for males, four for females, 30 for Hispanics, six for White non-Hispanics, Blacks and Asians. Seventy-one percent of drivers and 60 percent of passengers had a blood alcohol concentration greater than or equal to 22 mmol/L. Most cases (57 percent) had an Injury Severity Score of 1 (minor injury) or 0 (no injury). Alcohol use was associated with higher Injury Severity Scores. Road curvature of 20 degrees or greater was far more common at crash sites than at matched control sites one mile away (OR = 6.57, 95% CI = 2.93, 14.71). Guard rail placement along highly curved sections of roadway may be an effective preventive measure.

The Validity of 99mTc-Pyridoxylideneglutamate (P.G.) Cholescintigraphy as a Diagnostic Test for Cholecystitis

The purpose of this investigation was to determine the diagnostic value (validity) of technetium-99mpyridoxylideneglutamate cholescintigraphy (99mTc- PGC) in patients with and without cholecystitis and to compare its validity to those of oral cholecystography (OC) and ultrasonography (US). 99mTc-PGC was applied to 50 patients with acute, subacute, and/or chronic cholecystitis with cystic duct obstruction proven histologically and operatively, and also to 27 non-diseased volunteers and 43 patients with right upper quadrant abdominal pain who subsequently were proven free of gallbladder disease. In addition, 38 patients had OC, and 31 had US performed. The results shows that the sensitivity and specificity of 99mTc-PGC were 100%. Whereas for OC the sensitivity was 87%, specificity was 100%. For US the sensitivity was 70%, and specificity was 93%. The repeatability of 99mTc-PGC, OC, and US were 100%, 94% and 81% respectively. These data show that 99mTc-pyridoxylideneglutamate cholescintigraphy is a valid diagnostic tool in the evaluation of patients with cholecystitis, and is also safe and simple.

Epidemiologic study of physiological effects in usual and volunteer citrus workers from organophosphate pesticide residues at reentry

Biological parameters associated with organophosphate (OP) pesticide exposure were evaluated in a study of citrus harvesters. Changes in these parameters related to environmental residues of cholinesterase (ChE) inhibiting pesticides were studied. Further, it was determined whether usual and volunteer workers differed in their biochemical parameters after exposure to pesticide residues during field operations. Urine metabolite findings for usual farm workers showed that some exposure to OP pesticides had occurred. Too few workers were available during the reentry stage of the field study to evaluate the effect of this exposure on blood ChE. Baseline (nonexposure) acetylcholinesterase (AChE) and plasma cholinesterase (PChE) activities were significantly higher in usual (Mexican American) workers than in volunteer workers (student volunteers). Student volunteers in the test citrus grove showed statistically significant declines in PChE during the exposure period, yet changes in AChE activity, urine metabolites, and residue levels were very small. The implications of these findings are discussed in light of current reentry standards as well as future epidemiologic studies on reentry research.

Monitoring of grape harvesters for evidence of cholinesterase inhibition.

This report describes the results of a long-term monitoring study of 36 grape harvesters who were occupationally exposed to organophosphate pesticide residues following reentry into vineyards during September and October 1976. The study was designed to evaluate biochemical parameters associated with organophosphate pesticide residues. Insignificant changes in blood cholinesterase activity were found. Some workers had very low levels of organophosphate metabolites in the urine during the entire 6 wk of study. Ethion dioxon was the only pesticide residue detected on the grape leaves. The harvesting of wine grapes involves numerous work crews of four to six people each, requiring a highly mobile monitoring staff. A single stationary location for collecting blood and urine samples will result in massive losses to follow-up since the workers cannot be relied on to report on their own. It is recommended that, to maximize worker cooperation, future monitoring studies rely more on analyses of urine specimens and less on venipuncture for evidence of pesticide exposure.