Plan and operation of the NHANES I Epidemiologic Followup Study, 1992

OBJECTIVES: The NHANES I Epidemiologic Followup Study (NHEFS) is a longitudinal study that uses as its baseline those adult persons 25-74 years of age who were examined in the first National Health and Nutrition Examination Survey (NHANES I). NHEFS was designed to investigate the association between factors measured at baseline and the development of specific health conditions. The three major objectives of NHEFS are to study morbidity and mortality associated with suspected risk factors, changes over time in participants' characteristics, and the natural history of chronic disease and functional impairments. METHODS: Tracing and data collection in the 1992 Followup were undertaken for the 11,195 subjects who were not known to be deceased in the previous surveys. No additional information was collected in the 1992 NHEFS for the 3,212 subjects who were known to be deceased before the 1992 NHEFS data collection period. RESULTS: By the end of the 1992 NHEFS survey period, 90.0 percent of the 11,195 subjects in the 1992 Followup cohort had been successfully traced. Interviews were conducted for 9,281 subjects. An interview was conducted for 8,151 of the 8,687 surviving subjects; 551 interviews were administered to a proxy respondent because the subject was incapacitated. A proxy interview was conducted for 1,130 of the 1,392 decedents identified in the 1992 NHEFS. In addition, 10,535 facility stay records were collected for 4,162 subjects reporting overnight facility stays. Death certificates were obtained for 1,374 of the 1,392 subjects who were identified as deceased since last contact. Approximately 32 percent of the NHEFS cohort is known to be deceased with a death certificate available for 98 percent of the 4,604 NHEFS decedents.     

A population-based prospective evaluation of risk of sudden cardiac death after operation for common congenital heart defects

1. Ischaemic cardiac preconditioning represents an important cardioprotective mechanism which limits myocardial ischaemic damage. The aim of this investigation was to assess the impact of dichloroacetate (DCA), a pyruvate dehydrogenase complex activator, on preconditioning. 2. Rat isolated hearts were perfused by use of the Langendorff technique, and were subjected to either preconditioning (3 x 4 or 3 x 6 min ischaemia) or continuous perfusion, followed by 30 min global ischaemia and 60 min reperfusion. DCA (3 mM) was either given throughout the protocol (pretreatment), during reperfusion only (post-treatment), or not at all. Throughout reperfusion mechanical performance was assessed as the rate-pressure product (RPP: left ventricular developed pressure x heart rate). 3. In non-preconditioned control hearts, mechanical performance was substantially (P < 0.001) depressed on reperfusion (the RPP after 60 min of reperfusion (RPP(t=60)) was 4,246+/-974 mmHg beats min(-1) compared to baseline value of 21,297+/-1,728 mmHg beats min(-1)). Preconditioning with either 3 x 4 min or 3 x 6 min cycles caused significant protection, as shown by enhanced recovery (RPP(t=60) = 7,818+/-1,138, P < 0.05, and 11,123+/-587 mmHg beats min(-1), P < 0.001, respectively). 4. Addition of DCA (3 mM) to hearts under baseline conditions significantly (P < 0.001) enhanced systolic function with an increased left ventricular developed pressure of 108+/-5 mmHg compared to 88.3+/-3.0 mmHg in the controls. 5. Pretreatment with 3 mM DCA had no effect on recovery of mechanical performance in the non-preconditioned hearts (RPP(t=60) = 3,640+/-1,235 mmHg beats min(-1)) while the beneficial effects of preconditioning were reduced in the preconditioned hearts (3 x 4 min: RPP(t=60) = 2,919+/-1,060 mmHg beats min(-1); 3 x 6 min: RPP(t=60) = 8,032+/-1,367 mmHg beats min(-1)). Therefore, DCA had increased the threshold for preconditioning. 6. By contrast, post-treatment of hearts with 3 mM DCA substantially improved recovery on reperfusion in all groups (RPP(t=60) = 5,827+/-1,328 (non-preconditioned), 14,022+/-3,743 (3 x 4 min; P < 0.01) and 23,219+/-1,374 (3 x 6 min; P < 0.001) mmHg beats min(-1)). 7. The results of the present investigation clearly show that pretreatment with DCA enhances baseline cardiac mechanical performance but increases the threshold for cardiac preconditioning. However, post-treatment with DCA substantially augments the beneficial effects of preconditioning.     

Inhaled nitric oxide for adult respiratory distress syndrome after pulmonary resection

BACKGROUND: The adult respiratory distress syndrome (ARDS) developing after pulmonary resection is usually a lethal complication. The etiology of this serious complication remains unknown despite many theories. Intubation, aspiration bronchoscopy, antibiotics, and diuresis have been the mainstays of treatment. Mortality rates from ARDS after pneumonectomy have been reported as high as 90% to 100%. METHODS: In 1991, nitric oxide became clinically available. We instituted an aggressive program to treat patients with ARDS after pulmonary resection. Patients were intubated and treated with standard supportive measures plus inhaled nitric oxide at 10 to 20 parts/million. While being ventilated, all patients had postural changes to improve ventilation/perfusion matching and management of secretions. Systemic steroids were given to half of the patients. RESULTS: Ten consecutive patients after pulmonary resection with severe ARDS (ARDS score = 3.1+/-0.04) were treated. The mean ratio of partial pressure of arterial oxygen to the fraction of inspired oxygen at initiation of treatment was 95+/-13 mm Hg (mean +/- SEM) and improved immediately to 128+/-24 mm Hg, a 31%+/-8% improvement (p<0.05). The ratio improved steadily over the ensuing 96 hours. Chest x-rays improved in all patients and normalized in 8. No adverse reactions to nitric oxide were observed. CONCLUSIONS: We recommend the following treatment regimen for this lethal complication: intubation at the first radiographic sign of ARDS; immediate institution of inhaled nitric oxide (10 to 20 parts per million); aspiration bronchoscopy and postural changes to improve management of secretions and ventilation/perfusion matching; diuresis and antibiotics; and consideration of the addition of intravenous steroid therapy.     

Laparoscopic cholangiography: a prospective study

This paper describes the analysis of injury-related linked hospital morbidity data by admissions and by individual patients in Western Australia (WA) from 1990 to 1994. Over this five-year period, there were an average of 35,385 admissions and 30,524 people admitted each year for injuries in WA. The age-standardised rates for injury-related hospital admissions and persons admitted for injuries increased significantly, by 2.4% and 1.5% per year respectively, over the five-year period. The number of admissions and the number of persons admitted peaked in the 20-24 years age group but the highest rates were among those aged 75 years and above. Injuries accounted for nearly 10% of all hospital bed day costs and cost about $50 per head of population per year. The cost of hospitalisation rose steadily from $85.2 million in 1990 to $113.6 million in 1994, the average cost being nearly $100 million per year. The average cost per injury related hospital episode was $2,748. Generally, the cost per hospital episode was higher for males and increased with age, following a similar pattern to that for the average length of stay.     

Management of renal trauma at a rural, level I trauma center

Eotaxin is a potent and selective CC chemokine for eosinophils and basophils. We established several monoclonal antibodies (Mabs) allowing the neutralization and measurement of human eotaxin. Using the Mabs as probes, we demonstrated that normal eosinophils contained intracellular granule-associated eotaxin. Quantification of cell-associated eotaxin in different leukocyte subsets revealed that it was principally expressed in eosinophils. Finally, we showed that normal eosinophils released eotaxin upon stimulation with either of two secretagogues, C5a or ionomycin. These findings raise the possibility that eosinophil-derived eotaxin contributes to the local accumulation of eosinophils at the site of inflammation.     

A survey of provider experiences and perceptions of preferential access to cardiovascular care in Ontario, Canada

BACKGROUND: The public health insurance system in Canada is predicated on equal access to care for persons in need. OBJECTIVE: To determine the views and experiences of Ontario physicians and hospital administrators in providing patients with preferential access to specialized cardiovascular care on the basis of nonclinical factors. DESIGN: Survey with self-administered questionnaire. SETTING: Ontario, Canada. PARTICIPANTS: All Ontario cardiologists (n = 268), cardiac surgeons (n = 68), and hospital chief executives (n = 218) and random samples of internists (n = 300) and family physicians (n = 300). MEASUREMENTS: Elicited responses (yes or no) to questions on whether and why preferential access occurred and whether the respondents had been personally involved in such a situation. RESULTS: After undeliverable surveys and respondents no longer involved with acute care were excluded, the eligible response rate was 71.3% (788 of 1105 respondents). More than 80% of physicians and 53% of hospital chief executives had been personally involved in managing a patient who had received preferential access on the basis of factors other than medical need. Patients deemed most likely to receive such treatment were those with personal ties to the treating physicians (93% [95% CI, 91% to 95%]), high-profile public figures (85% [CI, 82% to 87%]), and politicians (83% [CI, 80% to 86%]). Physicians were significantly more likely than chief executives to indicate that hospital board members (81% and 68%; P < 0.001) and donors to hospital foundations (63% and 42%; P < 0.001) would receive preferential access. Most respondents indicated that preferential access was more likely to be provided if patients or families were well informed, aggressive, or potentially litigious. The survey did not permit estimation of the frequency of episodes of preferential access. CONCLUSIONS: Although equality of access is a cornerstone principle of Canada's universal health care system, some access to specialized cardiovascular services occurs preferentially on the basis of factors other than clinical need. The actual magnitude and consequences of this phenomenon remain unknown.     

The effect of renal transplantation on hyperhomocysteinaemia in dialysis patients, and the estimation of renal homocysteine extraction in patients with normal renal function

Cystinuria is an inherited genetic disorder that results in excessive cystine excretion through defects in renal dibasic amino acid transport. Due to the relative insolubility of cystine in urine, patients with this condition are prone to progressive and recurrent episodes of stone formation. Medical treatment is aimed at decreasing the concentration of cystine in the urine as well as increasing its solubility. A standard regimen includes dietary manipulation with hydration and moderate salt restriction, alkalinization, and thiol derivatives. Despite aggressive medical management, cystinuric patients are likely to suffer stone recurrences, and urologic intervention often is required. Contemporary technology permits the use of minimally invasive techniques for the majority of these patients, and advances in shock wave lithotripsy, percutaneous nephrolithotomy, and ureteroscopic lithotripsy obviate the need for open surgery in essentially all instances.