Prophylactic Anticoagulation In Patients Research Articles

Maternal and perinatal outcome in women with a history of stroke

Objective The purpose of this study was to determine recurrence risk and pregnancy outcome in 23 women with a history of stroke. Study design We conducted a descriptive study of 23 women (35 pregnancies) with a history of stroke. Charts were reviewed from 1990 through 2002. The data were analyzed for the antenatal treatment strategies, recurrence risk for stroke, and pregnancy outcome. Results There were 23 study patients with 35 subsequent pregnancies. Associated risk factors of the stroke were thrombophilia (5 women), sickle cell disease (3 women), maternal cardiac malformations (3 women), hypertension (3 women), oral contraceptive use (2 women), cerebral arteriovenous malformations (2 women), head trauma (1 woman), meningitis (1 woman), endocarditis (1 woman), and idiopathic reason (2 women). Four women with 9 subsequent pregnancies had a stroke that was associated with a previous pregnancy or postpartum incident. Two of these 9 pregnancies received anticoagulation (heparin, 1 pregnancy; heparin plus aspirin, 1 pregnancy). Nineteen women with 26 subsequent pregnancies had a stroke before pregnancy. Nine of these 26 pregnancies received anticoagulation (heparin, 5 pregnancies; aspirin, 3 pregnancies; heparin plus aspirin, 1 pregnancy). The remaining pregnancies did not receive prophylactic anticoagulation. Overall, there were 21 term deliveries, 8 preterm deliveries, 5 miscarriages, and 1 fetal death. Three of 34 pregnancies (9%) were small for gestational age infants. There were no recurrent thrombotic episodes during pregnancy or after delivery. Maternal complications included admission to the intensive care unit for uncontrolled hypertension in 1 patient. Conclusion Women with a history of stroke have a low risk of recurrent stroke (0%). This information is useful for the prepregnancy counseling of such individuals. The need for prophylactic anticoagulation in patients with a previous stroke cannot be answered by this study.

Maternal and perinatal outcome in women with a history of stroke

Objective The purpose of this study was to determine recurrence risk and pregnancy outcome in 23 women with a history of stroke. Study design We conducted a descriptive study of 23 women (35 pregnancies) with a history of stroke. Charts were reviewed from 1990 through 2002. The data were analyzed for the antenatal treatment strategies, recurrence risk for stroke, and pregnancy outcome. Results There were 23 study patients with 35 subsequent pregnancies. Associated risk factors of the stroke were thrombophilia (5 women), sickle cell disease (3 women), maternal cardiac malformations (3 women), hypertension (3 women), oral contraceptive use (2 women), cerebral arteriovenous malformations (2 women), head trauma (1 woman), meningitis (1 woman), endocarditis (1 woman), and idiopathic reason (2 women). Four women with 9 subsequent pregnancies had a stroke that was associated with a previous pregnancy or postpartum incident. Two of these 9 pregnancies received anticoagulation (heparin, 1 pregnancy; heparin plus aspirin, 1 pregnancy). Nineteen women with 26 subsequent pregnancies had a stroke before pregnancy. Nine of these 26 pregnancies received anticoagulation (heparin, 5 pregnancies; aspirin, 3 pregnancies; heparin plus aspirin, 1 pregnancy). The remaining pregnancies did not receive prophylactic anticoagulation. Overall, there were 21 term deliveries, 8 preterm deliveries, 5 miscarriages, and 1 fetal death. Three of 34 pregnancies (9%) were small for gestational age infants. There were no recurrent thrombotic episodes during pregnancy or after delivery. Maternal complications included admission to the intensive care unit for uncontrolled hypertension in 1 patient. Conclusion Women with a history of stroke have a low risk of recurrent stroke (0%). This information is useful for the prepregnancy counseling of such individuals. The need for prophylactic anticoagulation in patients with a previous stroke cannot be answered by this study.

Thrombosis prophylaxis in patient populations with a central venous catheter: a systematic review.

Central venous catheters (CVCs) are used in a wide variety of patients. Associated complications are thrombosis and infection. It is a matter of debate whether thromboprophylaxis is beneficial. We performed a systematic review of 3 different patient populations to render the available information in the literature more accessible to clinical practice: patients receiving parenteral nutrition (PN), patients with cancer, and patients admitted to intensive care units. Prophylaxis with heparin added to PN was found to give a nonsignificant reduction in the incidence of catheter-related thrombosis (pooled relative risk of randomized studies, 0.77; 95% confidence interval [CI], 0.11-5.48). In cancer patients, both low-dose warfarin and low-molecular-weight heparin significantly reduced the incidence of catheter-related thrombosis (relative risk of randomized studies, 0.25 [95% CI, 0.09-0.70] and 0.10 [95% CI, 0.01-0.71], respectively). So far, intensive care patients have hardly been studied with respect to thromboprophylaxis and the incidence of CVC thrombosis. Any effect of the type of catheter could not be established because of small numbers. There was no apparent increase in bleeding events with prophylactic anticoagulation in patients with CVCs. In the small number of patients studied, the addition of heparin to PN did not significantly decrease the risk of catheter-related thrombosis, whereas warfarin and dalteparin did decrease the thrombosis risk in cancer patients with CVCs. There is no apparent increase in bleeding events with prophylactic anticoagulants in patients with CVCs.

Detection of lupus anticoagulant identifies patients with autoimmune haemolytic anaemia at increased risk for venous thromboembolism.

Venous thromboembolism (VTE) is a well-recognized complication of autoimmune haemolytic anaemia (AIHA), and is a major cause of morbidity and mortality in this disorder. However, the incidence, pathogenesis and risk-factors for VTE in AIHA remain poorly defined. Lupus anticoagulants (LA) and anticardiolipin (ACA) antibodies are autoantibodies directed against epitopes on prothrombin or beta2 glycoprotein I (beta2-GPI). Both LA and ACA (together called antiphospholipid antibodies, APLA) are associated with VTE. We have prospectively studied the occurrence of VTE and APLA in 30 patients with AIHA. VTE was objectively documented in eight (27%) patients. APLA were detected in 19 (63%) patients with AIHA, of whom nine (30%) had a LA and 17 (57%) ACA. Seven patients had both LA and ACA. Among the eight patients with VTE, LA was detected in five (63%) and ACA in four (50%). There was a statistically significant association between presence of LA and occurrence of VTE (RR: 7.50, 95% CI: 1.25-45.2, P = 0.03). VTE is a frequent and life-threatening complication of AIHA. Detection of the lupus anticoagulant in patients with AIHA identifies individuals at significantly increased risk for VTE. Future studies should address the role of prophylactic anticoagulation in patients with AIHA.

Physician compliance with warfarin prophylaxis for central venous catheters in patients with solid tumors.

There is an established benefit of prophylactic warfarin in cancer patients with central venous catheters. This study assessed the compliance rate of prophylactic low-dose warfarin prescription in cancer patients with central venous catheters at a single institution. Oncology patients with central venous catheters were identified by a retrospective chart review. Information retrieved included whether prophylactic warfarin had been prescribed and whether the patient had suffered a thrombotic or bleeding event. After the initial chart review, physicians were notified of the benefits of warfarin prophylaxis, and subsequently, a physician-independent mechanism of prescribing prophylactic warfarin was instituted. After each of these interventions, we retrospectively reviewed a further two cohorts of patients to assess compliance with warfarin prophylaxis. During the baseline study, only 10% of patients were prescribed prophylactic warfarin. After physician notification, the compliance rate increased to only 20% (P =.3). After instituting the physician-independent mechanism of prescribing prophylactic warfarin, the compliance rate increased to 95% (P <.001). The rate of catheter-related thrombosis was 11% for patients who were prescribed warfarin compared with 21% in those who were not anticoagulated (P =.2). At our institution, the rate of prescribing prophylactic warfarin was low in this patient population, and there was a reluctance of treating physicians to change their prescribing practice. Mechanisms exist to improve the rate of anticoagulant prophylaxis in this clinical setting. We recommend that institutions review their rate of compliance with prophylactic anticoagulation for patients with central venous catheters and solid tumors.

IMPLICATIONS OF RECENT INSIGHTS INTO THE PATHOPHYSIOLOGY OF PAROXYSMAL NOCTURNAL HAEMOGLOBINURIA

IMPLICATIONS OF RECENT INSIGHTS INTO THE PATHOPHYSIOLOGY OF PAROXYSMAL NOCTURNAL HAEMOGLOBINURIA

A warfarin induction regimen for out‐patient anticoagulation in patients with atrial fibrillation

Currently available protocols for induction of warfarin anticoagulation employ initial doses of 10 mg and are best suited to in-patient use. However, with the increasing number of elderly patients with atrial fibrillation requiring anticoagulation, there is a need for a less intense regimen which could be used for out-patients. We have established such a regimen and report on its prospective evaluation in 3 7 patients referred for out-patient initiation of warfarin, and a non-randomized comparison with 37 in-patients, with similar diagnoses, commenced on a traditional warfarin protocol. After exclusion of five patients on amiodarone, all of whom experienced supratherapeutic International Normalized Ratio (INR) results, the new out-patient regimen, employing an initial 5 mg dose, resulted in a lower maximum INR during the first 21 d therapy (median 2.9 v 4.0; P = 0.0001) and fewer INRs >4.5 (2/36 v 9/33) compared to the traditional 10 mg regimen. Time to reach stable anticoagulation was similar with each regimen; however, the 5 mg regimen gave a more accurate prediction of maintenance dose (correlation coefficient for predicted versus actual maintenance dose, r = 0.985). In comparison to a traditional 10 mg protocol, the proposed 5 mg warfarin induction regimen proved both safer and more reliable for initiation of prophylactic anticoagulation in patients with atrial fibrillation.

Microsurgical Free Flap Transfer in Sickle Cell Disease

A patient with sickle cell anemia and recurrent ankle ulceration is presented. Multiple previous skin grafts did not resolve the painful ulcers. A radial forearm free flap was attempted. Despite preoperative transfusions to reduce her hemoglobin S levels, postoperative thrombosis occurred. The true risk of free flap failure in sickle cell anemia is unknown and there is still debate about the exact nature of the hypercoagulable state that exists in this disease. We recommend, however, that consideration is given to the use of prophylactic anticoagulation in patients undergoing complex procedures or in whom other risk factors have been identified.

The Efficacy of Low-Dose Heparin-Warfarin Anticoagulation Prophylaxis After Total Hip Replacement Arthroplasty

The prime therapeutic objective of prophylactic anticoagulation for patients undergoing total hip replacement is to reduce to a minimum fatalities from pulmonary embolism. Our low-dose heparin-warfarin prophylactic anticoagulation protocol affords significant protection in this regard (one fatal pulmonary embolism in 796 cases) without the use of venography or other objective tests to check for deep venous thrombosis and for all patients including those with venous disease or a history of prior thromboembolic disease. The 13.1% hematoma rate (5.0% late major) is a small, nonlethal, and acceptable price to pay for this protection.

Delayed cardiac tamponade associated with prophylactic anticoagulation in patients undergoing coronary bypass grafting: Early diagnosis with two-dimensional echocardiography

Pericardial tamponade occurring late in the hospitalization of a patient who has undergone a heart operation can be life threatening. Recognition of this insidious, but treatable, complication is difficult. Three patients experienced delayed tamponade while receiving warfarin prophylactically following coronary arter bypass. Two-dimensional echocardiography was useful in recognizing the effusion (and thus aided the diagnosis of tamponade) in each patients. The question of whether prophylactic antiocagulatin should be employed for patients undergoing coronary artery bypass procedures is also considered in light of both the present experience and collected reports from the literature.