Biomedical subjects

M J Tanasijevic

Publications and source records attributed to M J Tanasijevic.

26 records · Page 2Linked to original sources

PubMed1995

Total serum calcium reference intervals in postmenopausal outpatients.

The distribution of values of serum calcium has been studied in the following four outpatient populations: premenopausal (n = 411) and postmenopausal women (n = 399), men less than 50 years old (n = 365) and men over 55 years old (n = 361). Their respective average total serum calcium values (mg/dl) were 9.42, 9.56, 9.53, and 9.45. The reference intervals derived for total serum calcium (mg/dl) were 8.4-10.3 (premenopausal women), 8.4-10.7 (postmenopausal women), 8.6-10.5 (men less than 50 years old), and 8.4-10.4 (men over 55 years old). Increased total serum calcium levels were observed in the postmenopausal women as compared with both premenopausal women (p < 0.001) and with men over 55 years old (p < 0.003). Eight percent of the values obtained in postmenopausal women were above the current reference interval, as compared to 1.7% in premenopausal women, and 3.3% in men over 55 years old. In conclusion, the age-related increase in total serum calcium in postmenopausal female outpatients warrants a higher upper limit of the reference interval for this subpopulation.

Calcium↗

PubMed1995

Evolution beyond the shared services model of consolidated hospital clinical laboratories.

OBJECTIVE: To compare the operational and financial outcomes of the transition from shared laboratory services to a recentralized model, in a consolidated hospital system. SETTING: United Health Services Hospitals (Binghamton General, Wilson Memorial, and Ideal hospitals, New York State). INTERVENTION: Consolidation of hospital services and recentralization of laboratory testing to a single site (Wilson Memorial Hospital). MAIN OUTCOME MEASURES: Laboratory workload, testing efficiency, personnel and nonpersonnel expenses, analytic error rate, turnaround time, and proficiency-testing scores. RESULTS: The postintervention period (1988 to 1992) was characterized by a 51% and a 10% increase in the out- and inpatient workloads, respectively, with a concomitant 24% increase in testing efficiency. The salary expenses were 26% lower, while the total true cost savings ranged from $1,544,000 (11.6%) to $2,500,000 (21.9%) compared with the shared services model. The recentralization produced decreased analytic error rates and improved testing turnaround time. CONCLUSIONS: The total costs per test have been lowered in the recentralized model. Recentralization may provide further true cost savings over the shared services model while maintaining high-quality service.

Cost Control↗

PubMed1994

A predictive model for fetal lung maturity employing gestational age and test results.

Most laboratory tests for fetal lung maturity (FLM) are optimized to exclude false-negative predictions of absence of respiratory distress syndrome (RDS), with a reciprocal low predictive value for maturity. The authors employed FLM Surfactant/Albumin Ratio (FLM S/A) test results to construct a predictive model for FLM that included the obstetric estimates of gestational age. The charts of 388 newborns were abstracted and reviewed. The clinical outcome was the gold standard of the multivariate logistic analysis. Both the obstetric estimates of gestational age and the test result were significant predictors of the clinical outcome (P values of < .0002 and .001, respectively). The prediction rule for RDS as a function of both of these variables allows for adjustment of the test cutoffs, so that there is a consistent probability of RDS at the cutoff FLM S/A result for different gestational ages. Fetal lung maturity probability reporting may facilitate clinical decision-making.

Albumins↗

PubMed1994

The fiscal consequences of central vs distributed testing of glucose.

We have compared the operational, medical, and fiscal consequences of performing urgent glucose testing at the bedside vs in the central laboratory. The turnaround time (TAT) with bedside testing was only 1-2 min shorter than that from the central laboratory, to which specimens are sent by pneumatic tube and from which results are automatically broadcast by computer to the originating site. No significant adverse medical outcomes were associated with this difference in TAT. The cost of bedside testing is approximately twice that of central laboratory testing.

Blood Glucose↗

PubMed1993

Phosphorylation of the insulin receptor substrate IRS-1 by casein kinase II.

IRS-1, a principal substrate of the insulin receptor, is phosphorylated on serine, threonine, and tyrosine residues in a variety of tissues during insulin stimulation. Casein kinase II, an insulin-sensitive serine/threonine kinase, catalyzed the in vitro incorporation of 1 to 2 mol of phosphate/mol of recombinant rat IRS-1. Two-dimensional phosphopeptide mapping of IRS-1 phosphorylated by casein kinase II in vitro and IRS-1 immunoprecipitated from intact Chinese hamster ovary cells demonstrated multiple common phosphopeptides, suggesting that overexpressed IRS-1 is a substrate for casein kinase II in these cells. Moreover, the common phosphopeptides that appeared to be insulin-sensitive in intact cells comprised 22% of casein kinase II-catalyzed 32P incorporation into IRS-1 in vitro. These data suggest that casein kinase II mediates a portion of the insulin-stimulated serine/threonine phosphorylation of overexpressed IRS-1 in vivo. By using phosphoamino acid analysis, strong cation exchange analysis, manual Edman degradation, and automated amino acid sequencing, Thr-502 was identified as the major casein kinase II-catalyzed phosphorylation site in rat IRS-1. Furthermore, Ser-99, an additional site labeled at low yield, appeared to be contained in an insulin-sensitive phosphopeptide. Thus, casein kinase II-catalyzed phosphorylation of IRS-1 may be a component of the intracellular insulin signalling cascade.

Amino Acid Sequence↗

PubMedDate not supplied

How promptly are inpatients treated for critical laboratory results?

OBJECTIVE: The purpose of the study is to determine how frequently critical laboratory results (CLRs) occur and how rapidly they are acted upon. A CLR was defined as a result that met either the critical reporting criteria used by the laboratory at Brigham and Women's Hospital or other, more complex criteria. DESIGN: This is a retrospective cohort study in a large academic tertiary-care hospital. MEASUREMENTS: The proportion of chemistry and hematology results obtained in a 13-day period that met the hospital laboratory's critical reporting criteria were calculated. The charts of a stratified random sample of patients with CLRs due to sodium, potassium, and glucose were reviewed to determine the time interval until an appropriate treatment was ordered and the time interval until the critical condition was resolved. RESULTS: In 13 days, 1938 of 201,037 laboratory results (0.96%, or 0.44 per patient-day) met the hospital's critical reporting criteria. In the chart review, 222 CLRs were included in the stratified random sample, and 99 of these met the inclusion criteria. Among these 99 CLRs, the median time interval until an appropriate treatment was ordered was 2.5 hours. This interval was 1.8 hours when the CLR met the laboratory's criteria and a phone call was made, and 2.8 hours when the CLR met more complex criteria not requiring a phone call (p = 0.07). For 27 (27%) of the CLRs, an appropriate treatment was ordered only after five or more hours. The median time until the condition resolved was 14.3 hours: 12.0 hours for CLRs that met the hospital's criteria and 20.9 hours for the CLRs that met the more complex criteria (p = 0.006). CONCLUSION: Although CLRs meeting the hospital's criteria were reported promptly by the laboratory, treatment delays were still common. Results that did not meet the hospital's critical criteria but still represented serious clinical situations were more often associated with treatment delays. Difficulty communicating critical results directly to the responsible caregiver is the likely cause of some delays in treatment. New communications methods, including computer-based technologies, should be explored and tested for their potential to reduce treatment delays and improve clinical care.

Academic Medical Centers↗

PubMedDate not supplied

Improving response to critical laboratory results with automation: results of a randomized controlled trial.

OBJECTIVE: To evaluate the effect of an automatic alerting system on the time until treatment is ordered for patients with critical laboratory results. DESIGN: Prospective randomized controlled trial. INTERVENTION: A computer system to detect critical conditions and automatically notify the responsible physician via the hospital's paging system. PATIENTS: Medical and surgical inpatients at a large academic medical center. One two-month study period for each service. MAIN OUTCOMES: Interval from when a critical result was available for review until an appropriate treatment was ordered. Secondary outcomes were the time until the critical condition resolved and the frequency of adverse events. METHODS: The alerting system looked for 12 conditions involving laboratory results and medications. For intervention patients, the covering physician was automatically notified about the presence of the results. For control patients, no automatic notification was made. Chart review was performed to determine the outcomes. RESULTS: After exclusions, 192 alerting situations (94 interventions, 98 controls) were analyzed. The intervention group had a 38 percent shorter median time interval (1.0 hours vs. 1.6 hours, P = 0.003; mean, 4.1 vs. 4.6 hours, P = 0.003) until an appropriate treatment was ordered. The time until the alerting condition resolved was less in the intervention group (median, 8.4 hours vs. 8.9 hours, P = 0.11; mean, 14.4 hours vs. 20.2 hours, P = 0.11), although these results did not achieve statistical significance. The impact of the intervention was more pronounced for alerts that did not meet the laboratory's critical reporting criteria. There was no significant difference between the two groups in the number of adverse events. CONCLUSION: An automatic alerting system reduced the time until an appropriate treatment was ordered for patients who had critical laboratory results. Information technologies that facilitate the transmission of important patient data can potentially improve the quality of care.

Academic Medical Centers↗

PubMedDate not supplied

Appropriateness of antiepileptic drug level monitoring.

OBJECTIVES: To develop explicit, reliable appropriateness criteria for antiepileptic drug level monitoring and to assess the appropriateness of monitoring in one tertiary care institution. DESIGN: Appropriateness criteria derived from the literature and through expert opinion were used to evaluate a stratified random sample of antiepileptic drug level determinations obtained from chart review. SETTING: Tertiary care center performing more than 10,000 antiepileptic drug level determinations per year. PATIENTS: A total of 330 inpatients in whom antiepileptic drug levels were measured a total of 855 times. METHODS: Drug levels were assessed at least 200 times for each of four antiepileptic drugs (phenytoin, carbamazepine, phenobarbital, and valproic acid). MAIN OUTCOME MEASURES: The proportion of antiepileptic drug levels with an appropriate indication and, of those, the proportion sampled appropriately. RESULTS: Overall, 27% (95% confidence interval, 24% to 30%) of levels had an appropriate indication. Interrater agreement for appropriateness was substantial (kappa = 0.61). There was no significant difference in the appropriateness rate among the four drugs (range, 25% to 29%). Of the 624 antiepileptic drug level determinations considered inappropriate (73%), only four (0.6%) were more than 20% higher than the upper limit of normal, and none of the four patients had clinical signs of drug toxicity. A median of six levels (range, one through 69) was determined per patient, and the median interval between level determinations was 24 hours. Of the 27% of level determinations with an appropriate indication, 51% were sampled correctly, resulting in an overall appropriateness rate of 14%. CONCLUSIONS: Only 27% of antiepileptic drug level determinations had an appropriate indication, and half of these were not sampled correctly. Routine daily monitoring without pharmacological justification accounted for most of the inappropriate drug level determinations. Efforts to decrease inappropriate monitoring may result in substantial cost reductions without missing important clinical results.

Adolescent↗