PubMed Health⌕ Search

Biomedical subjects

G Backhouse

Publications and source records attributed to G Backhouse.

7 recordsLinked to original sources
PubMed1992

Effective reversal of warfarin-induced excessive anticoagulation with low dose vitamin K1.

Reversal of the anticoagulant effect of warfarin in patients with no active haemorrhage can be achieved by administration of intravenous vitamin K1. Currently recommended doses of intravenous vitamin K1, for this purpose often result in subsequent difficulties in anticoagulation. We observed the response to low dose intravenous vitamin K1 in patients requiring reversal of anticoagulant therapy. Ten consecutive patients received 1 mg and 21 further patients received 0.5 mg of intravenous vitamin K1. In 50% of the patients who received 1 mg of vitamin K1 the INR (International Normalised Ratio) fell below 2 at 24 h whereas in patients who received 0.5 mg the INR fell below 5.5 in all subjects after 24 h and in none did it fall below 2.0. No patient had any thrombotic or haemorrhagic complications and no difficulty was encountered in re-establishing anticoagulant control after 24 h. We recommend 0.5 mg of vitamin K1 as an effective and convenient method of predictable and fine control of oral anticoagulant therapy.

Adult↗
PubMed1987

A comparison of 3 and 6 weeks' anticoagulation in the treatment of venous thromboembolism.

One hundred hospital in-patients treated for pulmonary embolism (PE) and/or deep vein thrombosis (DVT) were randomly allocated to receive 3 or 6 weeks' anticoagulation with heparin and warfarin. At one year recurrence rates were 12% in the 6 week group and 10% in those treated for 3 weeks. No patient died as a result of recurrence. Our study suggests that 3 weeks' anticoagulation therapy, using intravenous heparin for the first 5 days and warfarin from the third day, is adequate for patients without persisting risk factors.

Adult↗
PubMed1986

Investigation of patients with abnormal response to warfarin.

In 55 patients in whom warfarin control had been satisfactory for at least 4 months, warfarin dose, plasma warfarin concentration and plasma clearance were measured. The mean dose to maintain the BCR (INR) between 2.3 and 3.3 was 5.1 +/- 2 mg day-1 (range 1.5-10 mg). Plasma warfarin concentrations and warfarin clearance were log-normally distributed with 95% confidence limits between 0.8 and 2.4 mg l-1 and 2.5 and 8.71 day-1 respectively. These confidence limits were used to construct algorithms which correctly predicted the cause of abnormal warfarin sensitivity in two patients and resistance in two further patients. These algorithms should help to identify the cause of abnormal warfarin responsiveness in the clinical setting.

Adolescent↗
PubMed1984

Flexible induction dose regimen for warfarin and prediction of maintenance dose.

Fifty patients with venous thromboembolic disease being treated by heparin infusion received a three day warfarin induction regimen tailored according to the prothrombin time (British comparative ratio) measured on days 2 and 3. A prediction of the final maintenance dose of warfarin was made on the basis of a prothrombin time measured on day 4. All patients were safely anticoagulated by day 6, and the prediction was accurate to within 1 mg in 46 patients. Predicted and actual maintenance doses were closely related (r = 0.867; n = 50; p less than 0.001). This scheme should prove helpful in the control of anticoagulation, particularly in patients likely to be sensitive to warfarin, and should shorten hospital stay.

Adult↗