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Biomedical subjects

R J Petersen

Publications and source records attributed to R J Petersen.

17 recordsLinked to original sources
PubMed1995

Cost-effectiveness and predictors of early extubation.

BACKGROUND: This study examined predictors and cost-effectiveness of early extubation after coronary artery bypass grafting. METHODS: Six hundred forty-five patients admitted to intensive care units after coronary artery bypass grafting at our institutions in 1993 were reviewed. There were 455 male and 190 female patients, which included all patients in DRG 106 and DRG 107. The patients were categorized into three groups: group A (269 patients) were extubated in less than 12 hours (7.55 +/- 2.5 hours), group B (291 patients) were extubated between 12 and 24 hours (16.85 +/- 3.3 hours), and group C (376 patients) were extubated any time after 12 hours. RESULTS: The reintubation rate for the entire group was less than 1%. Univariate preoperative analyses revealed small differences between groups A and B: only 6 of 25 variables were found to reach statistical significance. Stepwise logistic regression analyses were carried out in 269 patients of group A and 376 patients of group C. Older patients (log of age, p = 0.0001), female sex (p = 0.0129; odds ratio = 1.634), use of preoperative diuretics (p = 0.0010; odds ratio = 1.965) and unstable angina (p = 0.0301; odds ratio = 1.544) were noted to be clinical factors associated with late extubation (> or = 12 hours). Early extubation was accomplished in 42%; however, further analysis revealed that many patients who were intubated overnight should have been extubated sooner. CONCLUSIONS: Early extubation shortened the postoperative length of stay, resulting in reduction of cost and resource utilization. The average hospital charge per patient was approximately $6,000 less in the early extubation group.

Aged↗
PubMed1986

Indium-111 labeled leukocyte imaging following hepatic artery embolization.

The use of In-111 labeled leukocytes for abscess localization is becoming well established. The first report of In-111 imaging following hepatic embolization is presented. A 45-year-old man with adenocarcinoma of the colon and metastatic liver disease was treated for intractable pain using particulate embolization of the hepatic artery. In-111 leukocyte imaging was performed to rule out abscess formation. The distribution of the labeled leukocytes demonstrated hepatic uptake commensurate with Tc-99m sulfur colloid (SC) images. Areas of embolization did not accumulate tracer. Pathologic examination at autopsy correlated with the distribution of the labeled leukocytes. Thus, therapeutic embolization did not alter the normal distribution of this tracer in functional hepatic tissue.

Adenocarcinoma↗
PubMed1985

Disposal of low-level radioactive waste. Impact on the medical profession.

During 1985, low-level radioactive waste disposal has become a critical concern. The issue has been forced by the threatened closure of the three commercial disposal sites. The medical community has used radioactive isotopes for decades in nuclear medicine, radiation therapy, radioimmunoassay, and biomedical research. Loss of disposal capacity for radioactive wastes generated by these activities, by the suppliers of radioisotopes, and by pharmaceutical companies will have a profound impact on the medical profession.

Legislation as Topic↗
PubMed1983

Effect of acetaminophen on the leukocyte-labeling efficiency of indium oxine In 111.

The effect of acetaminophen on the labeling efficiency of leukocytes with indium oxine In 111 was studied. A blood sample was obtained from eight healthy men before and after they received acetaminophen 650 mg every four hours for 24 hours. After dividing the plasma from each sample into three portions, leukocytes were separated and labeled with indium oxine In 111. In an in vitro study, 200 ml of blood was obtained from one of the men, and the plasma was separated into four portions. Acetaminophen in 95% ethanol was added to three of the plasma fractions to produce acetaminophen concentrations of 4, 20, and 100 micrograms/ml; ethanol was added to the fourth fraction as a control. Each plasma fraction was then subdivided into three aliquots, and leukocytes were labeled as in the in vivo study. Mean leukocyte labeling efficiencies in both studies were calculated from the ratios of leukocyte radioactivity to initial radioactivity in the samples, expressed as percentages. Leukocyte labeling efficiencies before acetaminophen administration ranged from 79 to 85%; after administration, labeling efficiencies ranged from 70 to 87%. No significant differences in mean labeling efficiency before and after acetaminophen administration were noted in any of the subjects. Leukocyte labeling efficiencies in all in vitro plasma fractions were reduced, ranging from 54 to 63%, but no significant differences in labeling efficiency between any of the plasma fractions were found. Using the labeling procedures in this study, exposure of leukocytes from healthy men to acetaminophen in vivo or in vitro does not affect labeling efficiency with indium oxine In 111.

Acetaminophen↗
PubMed1982

Detection of metastatic liver disease. Use of liver scans and biochemical liver tests.

The records of 94 patients with a known diagnosis of extrahepatic cancer having liver scan, biochemical liver tests (alkaline phosphatase, SGOT, lactic dehydrogenase, and bilirubin levels, and subsequent liver biopsy within a six-week period were reviewed. The sensitivity, specificity, and accuracy of the scan and biochemical tests in the detection of metastatic liver disease were calculated. The most sensitive single examination was the group of biochemical liver tests. Liver scans performed in the presence of normal biochemical test results were insensitive when compared with the liver scan alone or the liver scan in the presence of abnormal biochemical test results. The specificity and accuracy of all tests and test combinations were statistically equivalent. Screening for hepatic metastases in patients with cancer is best accomplished with the more sensitive and less expensive group of biochemical liver tests, reserving the liver scan for those patients with abnormal biochemical test results.

Alkaline Phosphatase↗
PubMed1975

Ethylcellulose perfluorobutyrate: a highly non-thrombogenic fluoropolymer for gas exchange membranes.

A novel fluoropolymer prepared from ethylcellulose by acylation with perfluorobutyryl chloride has been shown to be remarkably non-thrombogenic in vena cava and renal embolus ring implant tests. Gas permeabilities of this fluoropolymer are dufficient to make it highly attractive for membrane blood oxygenators, either in the form of a thin film supported by a porous substrate or as a thin coating deposited onto microporous substrates. The broad solvent solubility of this fluoropolymer allows it to be fabricated into membranes by pratical processes. Good adhesion of coatings of this polymer to rigid and semi-rigid plastic surfaces can be achieved in many cases. This fluoropolymer represents an important new biomaterial for use in blood handling and oxygenation devices.

Animals↗