Evaluation of three dosage-prediction methods for initial in-hospital stabilization of warfarin therapy

Three dosage-prediction methods for initial in-hospital stabilization of warfarin therapy were evaluated. Adult inpatients who had received warfarin sodium 10 mg daily for less than three days were eligible for the study. After receiving their third warfarin dose, patients were randomly assigned to have their warfarin dosages adjusted using one of three dosage-prediction methods: by analog computer (n = 31), linear regression (n = 22), or empiric dosing by the physician (n = 34). A prothrombin time (PT) ratio (patient PT divided by control PT) between 1.3 and 2.5 was considered to be in the therapeutic range. For patients who achieved a stable PT ratio (defined as a PT ratio between 1.3 and 2.5 that varied by less than 0.05 on two consecutive days or by less than 0.1 on three consecutive days without a dosage change) before discharge, the number of days (time to stabilization) from administration of the first warfarin dose to achievement of the warfarin dosage that produced a stable PT ratio (stabilization dosage) was compared. A total of 54 patients met the study criteria for a stable PT ratio before hospital discharge (analog computer, n = 20; linear regression, n = 15; empiric dosing, n = 19). The mean times to stabilization were 6.8 days in the analog-computer group, 7.3 days in the linear-regression group, and 8.4 days in the empiric-dosing group; these times were not significantly different. All 20 stabilized patients in the analog-computer group achieved a stable PT ratio by the fourth dosage prediction.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evaluation of a new fine needle technique in routine percutaneous liver biopsy

A new fine needle aspiration biopsy technique (Vacu-Cut, 19.5 G) was compared to the 17 G Menghini needle in 20 consecutive patients scheduled for routine percutaneous liver biopsy (10 at random with each needle). The Menghini system was superior in producing sufficient material for histological assessment with 90% success on first pass biopsy (100% with 12 passes in 11 patients) as compared to 60% with the Vacu-Cut needle (90% with 16 passes in 10 patients). The latter was easier to use. Ability to reach a histological diagnosis was 100% with both needles. No major complications occurred: only one Vacu-Cut patient (10%) developed pain at the puncture site as compared to seven patients (65%) in the Menghini group, irrespective of number of passes. The ease of use and lower incidence of pain may favour the Vacu-Cut needle in selected ill patients.     

Evaluation of a two-point method for prediction of lithium maintenance dosage

A lithium test dose method, based on the two-point method of Perry et al. (1982), was evaluated in 20 patients for the prediction of maintenance dosage of slow-release lithium carbonate tablets. These predictions were compared with the predictions obtained from the dosing chart of Cooper et al. (1973). The two-point method accurately predicted the maintenance dosage within clinically acceptable limits, but dosages predicted from the dosing chart would have yielded much higher serum lithium concentrations.     

Influence of lornoxicam a new non-steroidal antiinflammatory drug on lithium pharmacokinetics

The pharmacokinetics of lithium carbonate have been studied in 12 normal young volunteers when given alone and in combination with lornoxicam, a novel non-steroidal anti-inflammatory drug. Peak and 12-h lithium concentrations were significantly higher when both drugs were given together than when lithium was given alone. Caution should be exercised if and when the drugs are co-prescribed.     

Evaluation of the interaction of lithium and alprazolam

A potential pharmacokinetic interaction between lithium and alprazolam was studied in 10 normal subjects. Pharmacokinetic parameters were determined from the following regimens: single-dose alprazolam, multiple-dose lithium, and multiple-dose alprazolam with lithium. Steady-state alprazolam clearance during multiple dosing with lithium was not different from that with the single dose of alprazolam. Lithium renal clearance decreased when it was coadministered with alprazolam (31.2 vs. 22.4 ml/minute, p less than 0.05). There was a small but significant increase in the steady-state area under the curve for lithium in the presence of alprazolam (10.3 vs. 11.1 mEq/hour/liter). The small increase in the serum lithium concentrations and decrease in lithium renal clearance was probably the result of lower urine flow rates (1.46 vs. 0.98 ml/minute, p less than 0.05) with the combination of the drugs. This is supported by a weak but significant linear relationship between urine flow rates and lithium renal clearance (N = 57, r = 0.353, p = 0.007). The percent of daily lithium dose recovered at steady-state from the 24-hour urine collection decreased significantly from 93.6% to 78.2% in the presence of alprazolam. This suggests that alprazolam may decrease lithium absorption. The results of this study do not support a definitive interaction of lithium and alprazolam and there is little clinical significance to the small rise in serum lithium concentrations.     

Evaluation of a rapid technique for detecting minor tranquilizers

A technique, based on the inhibition by foot-shocks of a simple ongoing behaviour in mice (ambulation), is suggested for the preliminary screening of the minor tranquilizers. The effect of a large number of psychotropic drugs was studied: they include minor tranquilizers, hypnotics, anticonvulsants, antihistamines, neuroleptics, antidepressants, antiparkinsonism agents, stimulants, analgesics and others. The efficiency, specificity, reliability, simplicity and disadvantages of the method are discussed.     

Medication pass observation, a new survey technique

The United States Department of Health and Human Services, Health Care Financing Administration now requires that surveyors of pharmaceutical services in hospitals include a medication pass observation in the survey process. This observation affords the surveyor the opportunity to follow medications through the complete system, that is, from the time that the medication is prescribed by the physician to the time that it is administered to the patient. This enables the surveyor to determine if the quality of care provided to the patient meets the intent of the federal and state regulations. The article describes the surveyor's technique for performing the medication pass observation which has become an integral part of the survey process.     

Evaluation of a new semi-rigid intravenous container

Mercy Hospital, in cooperation with McGaw Laboratories, conducted a pre-marketing evaluation of a new intravenous solution container made of a polyallomer thermoplastic, polyolefin. Following a four-month evaluation period using the Accumed container in the pharmacy intravenous admixture program and on all nursing units, the container was evaluated by both the pharmacy and nursing staffs and compared with our present system, Viaflex. A questionnaire prepared and supplied by McGaw Laboratories allowed nurses to evaluate the container subjectively. A questionnaire was also prepared for members of the pharmacy staff, both professional and supportive personnel, to use in evaluating the container. In addition, a time and motion study was developed to compare the Viaflex, Travenol glass, and Accumed containers in all areas of the hospital where intravenous solutions were used. Both the subjective and objective evaluations demonstrated acceptance by the Departments of Pharmacy and Nursing, and the Accumed container performed comparably with the Viaflex and glass containers tested in intravenous admixture preparation and in their administration. A list of properties of the "ideal" system is proposed.     

Evaluation of a quality assurance technique for a pharmacokinetic dosing service

A quality assurance (QA) technique that measured process and outcome was tested on a clinical pharmacokinetic dosing service (CPDS). The process measurement criteria evaluated the CPDS pharmacists' ability to maintain serum aminoglycoside levels within the desired range (peak 6-10 micrograms/ml, trough less than 2.0 micrograms/ml). The outcome measurement criteria evaluated the patients' clinical response to the aminoglycoside therapy based on changes in the patients' temperature, white blood cell count, bacterial cultures, and other variables. The process evaluation found that in a majority of the patients (80 percent), the CPDS pharmacist was performing at a level exceeding the process criteria. The outcome evaluation found that in a majority of the patients (76 percent), the therapeutic outcome criteria were not met. Statistical analysis using Spearman's Rho was not able to relate process and outcome measures significantly (p greater than 0.05). The patient outcome criteria may not have accurately measured patient outcome because of inflexibility, not measuring other patient variables, and the lack of a subjective component. Validation of the QA technique was not possible in this study.     

Evaluation of a new vancomycin dosing method

Thirty-one patients who were prescribed vancomycin therapy at our institution since January 1, 1986, were dosed using the guidelines as described by Lake and Peterson. Peak and trough vancomycin serum concentrations were measured at steady state: 24 (77%) peak serum concentrations were within the range of 20-30 mg/L, and 24 (77%) trough serum concentrations were within the range of 5-10 mg/L. We have found that the method of Lake and Peterson is satisfactory for initiating vancomycin therapy in most patients. Some, however, may not achieve optimal serum concentrations using these guidelines alone, and their regimens may have to be adjusted based upon actual serum concentration data.     

Evaluation of a new germicidal hand creme

A new germicidal hand creme (Wash & Heal, Med-Chem Labs, Okemos, MI) was evaluated for its ability to reduce bacterial levels on the hands. Colony counts of coagulase-negative staphylococci were significantly reduced immediately after use, with notable antimicrobial activity present for the next 90-120 minutes. The germicidal creme was more active against staphylococci than gram negative bacilli. The creme's germicidal activity occurred rapidly and was targeted against gram positive cocci found on the skin; whereas the bar soap's activity occurred more slowly and had a broader target. This creme could be used between hand washings to further reduce microbial flora of the hands.     

Colonoscopy: a new diagnostic and therapeutic technique.

Since January 1974, 150 colonoscopies have been performed. The method is reviewed and indications for diagnosis or therapy are outlined and examples illustrating these indications are given. It has proved to be an excellent diagnostic and therapeutic technique.     

MolDock: a new technique for high-accuracy molecular docking

In this article we introduce a molecular docking algorithm called MolDock. MolDock is based on a new heuristic search algorithm that combines differential evolution with a cavity prediction algorithm. The docking scoring function of MolDock is an extension of the piecewise linear potential (PLP) including new hydrogen bonding and electrostatic terms. To further improve docking accuracy, a re-ranking scoring function is introduced, which identifies the most promising docking solution from the solutions obtained by the docking algorithm. The docking accuracy of MolDock has been evaluated by docking flexible ligands to 77 protein targets. MolDock was able to identify the correct binding mode of 87% of the complexes. In comparison, the accuracy of Glide and Surflex is 82% and 75%, respectively. FlexX obtained 58% and GOLD 78% on subsets containing 76 and 55 cases, respectively.     

Synthesis and psychotropic activity of new long-acting lithium compounds

Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 27, No. 3, pp. 19–22, March, 1993.     

Evaluation of a new Seralyzer assay for carbamazepine

The performance of a new dry-phase, strip immunoassay technique for the analysis of serum carbamazepine concentrations (Seralyzer), was compared to a standard high performance liquid chromatography (HPLC) method. One hundred blood samples were collected from 87 patients and analysed using both techniques. There was no significant difference between the concentrations measured by either technique, and the results were highly correlated (r = 0.97). The Seralyzer is a rapid and accurate method for use in carbamazepine therapeutic drug monitoring.