Biomedical subjects

A Holden

Publications and source records attributed to A Holden.

8 recordsLinked to original sources

PubMed1992

Oral anticoagulant therapy: practical considerations.

The key to safe and effective oral anticoagulation is to have an understanding of the rationale for dosing guidelines and therapeutic ranges; an appreciation of the imprecision of prothrombin time testing and its standardization; knowledge of the factors influencing prothrombin time response; and awareness of the importance of patient empowerment via ongoing patient education. This review focuses on the routine management of oral anticoagulant therapy to provide these practical insights and to promote safe and effective therapy.

Anticoagulants↗

PubMed1989

Thyroid lymphoma.

We have reviewed the local experience of 15 cases of thyroid lymphoma with a view to documenting the epidemiology, presentation, management and prognostic factors governing outcome for this rare condition. All the patients were European despite the fact that 15 per cent of the local population is either Maori or Polynesian. The average age at presentation was 62 years and 13 of the 15 patients were women. The duration of symptoms was short: on average 9 months. Where feasible a definitive resection of the lesion was performed but this could only be performed in six of the 15 cases. The commonest histological type was non-Hodgkin's lymphoma which accounted for 14 of the 15 cases with the large cell variant being the most common (five cases). The mean period of follow-up was 3.3 years: only eight patients were alive and well at that time. The prognostic factors that influenced outcome were: (1) the histology of the lesion - large cell lymphoma carried a bad outlook; (2) whether the lesion could be totally resected or not - five out of six patients undergoing total resection remain alive and well; (3) the presence of pre-existing Hashimoto's thyroiditis was a favourable prognostic factor as only one patient without underlying Hashimoto's disease or positive antithyroid antibodies was alive at the end of the study; (4) male sex may also be an unfavourable prognostic factor as both men in the study died of disease 0.3 and 5 years after diagnosis.

Adult↗

PubMed1989

Cost effectiveness of monitoring warfarin therapy using standard versus capillary prothrombin times.

The authors assessed the cost effectiveness of monitoring warfarin therapy guided by standard plasma prothrombin times performed on blood samples obtained by venipuncture versus prothrombin times performed on capillary whole blood samples obtained by fingerstick. Twenty patients receiving long-term oral anticoagulation had either standard or capillary prothrombin times determined every other week for eight weeks in a cross-over design. All time intervals were monitored, including receptionist, secretarial, nursing, phlebotomy, etc., and costs for all materials, procedures, and labor were calculated. The total cost per test by the capillary whole blood prothrombin time method was significantly less than by standard prothrombin time methods ($7.55 vs. $15.64) even though the nurse-patient encounter time was greater per test for the capillary method (12.4 minutes vs. 8.3 minutes). The management of oral anticoagulation guided by prothrombin times performed on instrumentation designed to sample capillary whole blood should result in a significant cost savings, and because of the immediate availability of results, provide the potential for improved health care.

Administration, Oral↗

PubMed1989

Comparison between videotape and personalized patient education for anticoagulant therapy.

To assess the effectiveness of videotape patient education, 22 patients were randomized to receive either videotape or personalized teaching for oral anticoagulant (warfarin) therapy. Both groups scored significantly higher on a questionnaire designed to assess knowledge gained after instruction, with no significant difference between the two groups. Videotape instruction required substantially less nursing time. A second questionnaire assessed patient satisfaction with respect to both methods, which were rated equally effective and worthwhile. Videotape teaching is an effective and well-accepted alternative form of patient education requiring significantly less personnel time.

Administration, Oral↗

PubMed1989

Patient self-management of oral anticoagulation guided by capillary (fingerstick) whole blood prothrombin times.

Physician management of long-term oral anticoagulation is labor-intensive and costly. Moreover, errors of communication may lead to complications. We assessed the ability of patients to regulate their own therapy based on fingerstick prothrombin times (PTs) in order to avoid these problems. Such management was made possible by the availability of a device capable of measuring a PT from a capillary sample of whole blood. Sixteen patients adjusted their warfarin therapy based on specially developed guidelines for a mean duration of 43 weeks (range, 8 to 92 weeks). Four hundred fifty-eight PTs were measured by patients at home during the entire study. Three hundred ninety-three were in therapeutic range and patients correctly continued their dosages. Of the 65 nontherapeutic PTs, patients made correct dose adjustments in 49 and incorrect adjustments in 16. These incorrect adjustments were minor and judged to be clinically insignificant. They often resulted from a misunderstanding of the dosage guidelines. Given the slow onset of warfarin's effect, the assessment of the PT on a weekly or biweekly basis, and the ability to refine dosage guidelines, these errors were not felt to represent a serious drawback to the concept of warfarin self-management. No complications of therapy occurred during the study. Although this mode of therapy needs further evaluation, this pilot study suggests that patient self-management is feasible and that this model of anticoagulant care offers the potential for improved care at reduced cost.

Administration, Oral↗

PubMed1988

Benzocaine--an unsatisfactory indicator of topical local anaesthetic sensitization for the U.K.

Three thousand consecutive patients undergoing patch tests were tested with a mix of benzocaine, amethocaine hydrochloride and cinchocaine hydrochloride. Eighty-four subjects (2.8%) were found to be allergic to this mix. Forty of these were patch tested with the constituents of the mix: 21 (52.5%) patients were sensitive to amethocaine hydrochloride or cinchocaine hydrochloride or both, but not to benzocaine. We recommend that a non-irritant 'caine mix' containing benzocaine, cinchocaine and amethocaine should be included in the standard patch test series for the U.K.

Benzocaine↗

PubMed1988

Age-related risks of long-term oral anticoagulant therapy.

Long-term oral anticoagulant therapy is critical to the optimal management of various thromboembolic and vascular disorders. To determine whether age is related to the development of bleeding complications in patients who are receiving long-term oral anticoagulant therapy, the records of 321 patients who were followed up in the university hospital outpatient anticoagulation clinic during an eight-year period were reviewed. During this period, 61 patients (19%) developed minor bleeding complications, and 14 patients (4.4%) developed major bleeding complications. In utilizing a life-table approach to adjust for varying lengths of follow-up, the risk of initial minor bleeding complications was found to be greatest within the first three months (14%). For major bleeding complications, risk increased throughout the first two years of anticoagulation clinic follow-up, with no particular period of greatest risk. No significant differences in the risk of initial minor or major bleeding complications were observed in the various age groups that were examined (less than 50, 50 to 59, 60 to 69, and greater than or equal to 70 years). A multivariate regression approach, controlling for several potentially confounding factors, confirmed the lack of an association of age with the risk of minor or major bleeding complications. The results of this retrospective follow-up study suggest that patient age, in and of itself, should not be considered a primary factor in assessing the risk of long-term oral anticoagulant therapy.

Administration, Oral↗

PubMed1987

Safety and efficacy of long-term oral anticoagulation in cancer patients.

The course of long-term oral anticoagulation in 25 patients (186 patient-months) with cancer managed in an outpatient anticoagulation clinic was analyzed to determine the frequency of complications. Major and minor hemorrhagic complications occurred in 10.7% and 32% of treatment courses, respectively, for an incidence of 1.6% and 4.8%, respectively, per patient-month. Recurrent thromboembolism occurred in 14% of treatment courses. These results are better than previous reports in the literature, but worse than our overall anticoagulation clinic experience. Patients with cancer requiring anticoagulation are at a higher risk of hemorrhagic and thrombotic complications. Accordingly, we recommend that such patients be monitored closely, preferably by physicians experienced with such therapy, as in an anticoagulation clinic, to avoid an excessive degree of morbidity.

Adult↗