Reevaluation of a weight-based heparin dosing nomogram: is institution-specific modification necessary?

OBJECTIVE: To compare a heparin dosing nomogram using an initial infusion rate of 18 units/kg/h with physician-directed heparin prescribing and with a modified version of the nomogram adjusted for institution-specific data. METHODS: During consecutive phases of this cohort study, patients' intravenous heparin therapies were initiated and adjusted by using one of the following three methods: (1) physician-directed dosing, (2) a body weight-based dosing nomogram with an initial infusion rate of 18 units/kg/h, and (3) a body weight-based dosing nomogram with an initial infusion rate determined by the median dose of heparin (in units/kg/h) required to achieve therapeutic activated partial thromboplastin times (aPTTs) during the first two phases. The time required to achieve therapeutic aPTTs as well as the percentage of initial aPTTs in the therapeutic range were compared for the three phases. RESULTS: The heparin dosing nomogram in which the initial infusion rate was adjusted for our individual institution resulted in a statistically shorter median time until aPTTs were in the therapeutic range than did either the physician-directed dosing or unmodified nomogram groups (6.1 h in the modified nomogram group, 10.5 h in the physician-directed group, 21.5 h in the unmodified nomogram group; p < 0.05 for all differences). Use of the institution-specific nomogram resulted in the greatest percentage of initial aPTTs in the therapeutic range (84% in the 13 units/kg/h nomogram group vs. 47% in the physician-directed group and 18% in the 18 units/kg/h nomogram group; p < 0.05 for all differences). CONCLUSIONS: Use of a heparin dosing nomogram with an initial infusion rate of 18 units/kg/h resulted in prolongation of the time to reach therapeutic aPTTs. By modifying the nomogram for use at an individual institution, we reduced the time to achieve therapeutic range of aPTTs while still reducing the likelihood of excessive anticoagulation of patients.

Physician practices regarding anticoagulation and cardioversion of atrial fibrillation.

BACKGROUND: Stroke is one of the most significant potential complications in patients who are undergoing cardioversion for atrial fibrillation. To minimize the risk of stroke, the American College of Chest Physicians' (ACCP's) Third Consensus Conference on Antithrombotic Therapy developed specific recommendations regarding anticoagulation before and following elective cardioversion of patients with atrial fibrillation. OBJECTIVE: To determine if patients undergoing cardioversion for atrial fibrillation are administered anticoagulants according to the ACCP's Third Consensus Conference on Antithrombotic Therapy recommendations. DESIGN: A retrospective review of cases of atrial fibrillation at a tertiary care teaching hospital to determine if physicians are routinely following these recommendations. METHODS: Data were collected for the year 1994 for all patients admitted to a tertiary care teaching hospital with a diagnosis of atrial fibrillation (n = 111). The ACCP's recommendations that were evaluated included the following: patients undergoing elective cardioversion for atrial fibrillation should receive anticoagulation for 3 weeks before and 4 weeks following cardioversion except in cases of new-onset atrial fibrillation, and warfarin and heparin should be administered jointly for several days before discontinuation of heparin therapy. RESULTS: Of the 111 patients who presented with a diagnosis of atrial fibrillation, 51 underwent elective cardioversion. In 18 (35%) of 51 cases, physicians failed to follow at least one of ACCP's recommendations regarding anticoagulation. These included failing to (1) administer anticoagulants to patients for 3 weeks before elective cardioversion (n = 14); (2) administer anticoagulants to patients for 4 weeks following cardioversion (n = 6); and (3) overlap heparin and/or warfarin therapies for 72 hours (n = 4). Six cases failed to meet more than one of these recommendations. CONCLUSION: Physicians are not routinely following the ACCP's Third Consensus Conference on Antithrombotic Therapy recommendations regarding anticoagulation in elective cardioversion of atrial fibrillation, thus increasing patients' risk of stroke.

The effect of prophylactic nifedipine on renal function in patients administered contrast media.

STUDY OBJECTIVE: To determine if prophylaxis with nifedipine could decrease the frequency of contrast medium-induced renal impairment. DESIGN: Prospective, randomized clinical trial. SETTING: A university-affiliated hospital. PATIENTS: Patients undergoing scheduled radiologic examinations involving infusion of contrast media. INTERVENTIONS: Forty-two patients were randomized to receive nifedipine 10 mg orally 1 hour before the imaging procedure, and 43 to receive no treatment. MEASUREMENTS AND MAIN RESULTS: Baseline serum creatinine levels were compared with maximum levels 24 and 48 hours after administration of contrast medium. No statistically significant difference was seen in either the mean change or mean percentage change in serum creatinine between the control and nifedipine groups. The mean changes in serum creatinine were +7.4 mumol/L in the control group and +2.7 mumol/L in the nifedipine group (p = 0.33); the mean percentage changes were +10.2% and +4.8%, respectively (p = 0.54). CONCLUSION: Regardless of statistical analysis, it is unlikely that elevations in serum creatinine of this magnitude (< 0.1 mg/dl) are of clinical significance. We therefore conclude that prophylactic nifedipine is not clinically beneficial in preserving renal function in patients receiving contrast medium and that the agent should not be routinely administered for this purpose.

Treatment of bacterial vaginosis.

OBJECTIVE: The purpose of this article is to review the treatment options for bacterial vaginosis, including the newer topical antibiotics, metronidazole gel and clindamycin cream. The article also examines the controversies over whether bacterial vaginosis is a sexually transmitted disease and whether asymptomatic women should be treated. DATA SOURCE: A MEDLINE search was conducted to identify pertinent literature, including review articles. STUDY SELECTION: Emphasis was placed on those clinical trials using metronidazole gel or clindamycin cream. Studies addressing the complications of bacterial vaginosis in pregnancy, the risk of treatment in pregnancy, and the method of transmission of the disease also were reviewed. DATA EXTRACTION: Clinical studies evaluating clindamycin cream and metronidazole gel were scarce; therefore, data from all available trials were reviewed. The objectives, methodology, and results from other studies were reviewed; those addressing complications of the disease and risks and benefits of treatment were included. DATA SYNTHESIS: There is evidence both for and against bacterial vaginosis being a sexually transmitted disease. Potential complications of the disease may warrant treatment of certain asymptomatic women, especially during pregnancy. Treatment options include oral or vaginal metronidazole or clindamycin, all of which provide high cure rates. Vaginal antibiotics result in minimal risk to the fetus in pregnant patients. CONCLUSIONS: Complications of bacterial vaginosis may be associated with significant morbidity, especially among pregnant women. Treatment of asymptomatic women with the disease is controversial, but may be justified in certain high-risk populations. The topical agents, clindamycin vaginal cream 2% and metronidazole vaginal gel 0.75% provide a safe, effective, but expensive alternative to oral antibiotic regimens for the treatment of bacterial vaginosis.

Survey and evaluation of newsletters marketed to family physicians.

BACKGROUND: Newsletters are marketed to physicians to provide a concise, accurate, and timely overview of the medical literature. The goal of these newsletters seems to be to present information that can be a suitable substitute for reading the original article. The purpose of this paper is to describe and evaluate newsletters pertinent to family physicians. METHODS: Newsletters appropriate for family physicians were selected by collecting newsletter advertisements and by searching newsletter directories. A 3-month sample and pertinent data were collected from the publishers. Evaluation criteria included accuracy and completeness of the abstracts, scope of coverage of the medical literature, and relevance of article sources. RESULTS: Eight newsletters were collected and evaluated. Accuracy was high for the evaluated abstracts. Abstract completeness averaged only 70 percent (range 55 percent to 92 percent). The type and source of abstracted articles varied widely among the newsletters. CONCLUSION: Newsletters available to family physicians vary widely; personal evaluation should supplement the results of the evaluation.

Use of a personal computer to monitor adverse drug reactions.

The Pharmacy department at Sewickley Valley Hospital, Sewickley, Pennsylvania, has developed an adverse drug reaction database using DBase III Plus software. The computer database allows instant, custom manipulation of large amounts of data, and aids in the analysis of adverse drug reaction reports for quality assurance purposes.