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Query: UMLS:C0034065 (pulmonary embolism)
 14,979 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Heparin and warfarin sodium (Coumadin, Panwarfin, Sofarin) are used most often to treat acute and recurrent venous thromboembolic disease, arterial disease, valvular heart disease, and atrial fibrillation. These agents along with dextran, pneumatic compression devices, and gradient stockings are also used to prevent deep venous thrombosis and pulmonary embolism in patients at high risk (eg, those with venous stasis, lower limb or spinal cord trauma, clotting abnormalities). Anticoagulation therapy is monitored by maintaining the activated partial thromboplastin time and the prothrombin time in the therapeutic range.
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PMID:Using anticoagulants safely. Guidelines for therapeutic and prophylactic regimens. 188 10

All surgical patients are at risk for the development of deep venous thrombosis and subsequent pulmonary embolism or postphlebitic syndrome. The evolution of ultrasonographic imaging has increased the awareness of prevention, diagnosis, and treatment of deep venous thrombosis. Duplex imaging and Doppler color flow imaging have made the diagnosis of deep venous thrombosis relatively simple, painless, inexpensive, and definitive. These procedures have gained acceptance by both patients and physicians. Several risk factors have been identified that increase the chance of the development of deep venous thrombosis. These factors include a history of deep venous thrombosis, presence of a malignant process, increasing age, cigarette smoking, obesity, prolonged bed rest, and general anesthesia. The greater the number of risk factors, the more aggressive prophylaxis should be. Means of prophylaxis have improved, and surgeons now generally agree that some form of prophylaxis is required. Heparin and intermittent compression devices appear to be equally effective in preventing deep venous thrombosis. The addition of venous monitoring in high-risk patients permits immediate identification of the presence of deep venous thrombosis. During the last decade, the treatment of patients with deep venous thrombosis has changed little. Heparin followed by warfarin remains the treatment of choice. A small group of patients receive fibrinolytic therapy for deep venous thrombosis. Although the incidence of postoperative deep venous thrombosis has decreased during the last decade, it remains a significant complication.
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PMID:Deep venous thrombosis and pulmonary embolism. 194 69

Standard unfractionated heparin is a mixture of mucopolysaccharide chains of various length that may vary from 5000 to 30,000 daltons. Heparin is only effective as an anticoagulant in the presence of a plasma protein termed antithrombin III, with which it forms a complex. High- and low-affinity heparin are 2 types that readily bind or do not bind, respectively, to antithrombin III. The pharmacokinetics of unfractionated heparin are compatible with a model based on the combination of a saturable and a linear mechanism. The primary indication for intravenous infusion of conventional heparin is to prevent extension of an established arterial, venous or intracardiac thrombus. The average requirement is 400 U/kg/24h. Subcutaneous administration of 5000U of concentrated unfractionated heparin, administered every 8 or 12 hours, is effective and safe in the prevention of postoperative venous thrombosis and pulmonary embolism in patients at medium thrombotic risk. Adequate prophylaxis is also obtained in patients at high thrombotic risk if 5000U of heparin combined with 0.5mg dihydroergotamine is given subcutaneously 3 times daily, or by monitoring the 3 subcutaneous doses of heparin in order to maintain an adjusted activated partial thromboplastin time (APTT) of around 50 to 70 seconds. Low molecular weight heparins have been produced by a variety of techniques and their molecular weights range from 3000 to 9000 daltons. These preparations have a ratio of anti-factor Xa activity to anti-factor IIa activity of about 4, while the ratio for unfractionated heparin is 1. After intravenous administration of low molecular weight heparin, the half-life of the anti-factor Xa activity is considerably longer than for unfractionated heparin, while the anti-factor IIa half-lives are similar. In contrast to unfractionated heparin, low molecular weight heparin is completely absorbed after subcutaneous administration and its biological half-life is almost twice as long. In spite of certain differences with regard to the ratio between factor Xa and IIa inhibition, the various low molecular weight preparations show a rather similar absorption pattern. The bioavailability of all low molecular weight heparin fractions is substantially higher than that of unfractionated heparin, which renders their use more simple. Low molecular weight heparins less readily enhance platelet aggregation although there is no evidence that low molecular weight heparins are less antigenic or that they do not interact with platelet IgGFc receptor. A lower bleeding incidence for equivalent antithrombotic efficacy of fractionated heparins when compared to unfractionated heparins has yet to be established in humans.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Pharmacotherapeutic aspects of unfractionated and low molecular weight heparins. 196 34

Acute and subacute deep venous thrombosis can be followed by two serious complications: pulmonary embolism feared in the early stadium and the postthrombotic syndrome (PTS) as a late complication. After a lapse of months and years there might appear a complete or incomplete recanalization, but the valves of the veins will be destroyed. Therefore it is understandable to strive first an active therapy as thrombectomy or thrombolysis to remove thrombosis. There will be released a physiological tissue plasminogen activator from the endothelium of the vein increasing a local fibrinolytic activity. But it is not strong enough to reopen the occlusion within a few days. This is only possible adding exogenous activators as streptokinase, urokinase and recently rt-PA. Heparin is well known at low-dose subcutaneously for thrombosis prophylaxis. The high doses of heparin infusion intravenously with 30-40,000 units daily are used "therapeutically" inhibiting growth-promotion of the thrombus and reducing the incidence of pulmonary embolism markedly. In respect of a postthrombotic syndrome (oedema, leg ulcers) it needs the evaluation of the early and follow up late results and the analysis of efficiency and risk of the two models of treatment. It was necessary comparing the success rate of reopening of the occluded veins after some days and follow up 5 or 6 years in clinical studies. The reopening rate in thrombolysis was about 3 times higher than in heparin therapy. But in contrast bleeding was 3 times lower in heparin therapy. For the long term follow up, physical examination, doppler-sonography phlebodynamometry and vein occlusion plethysmography were assessed. The acute intervention, regarding treatment, turned out to be the crucial prognostic parameter. Syndromes and clinical findings did indeed correlate quite well with the outcome of fibrinolytic treatment. Postthrombotic syndrome was rare in cases with complete patency. In cases where patency was only partially or not at all achieved, postthrombotic syndrome was present to a higher degree the more central and the more extensive the remaining thrombus was. In deep venous thrombosis of the lower extremity thrombolytic therapy is recommended mostly to younger patients with acute, the popliteal and the femoral vein including thrombosis, except of contraindications. More over in each of an individual case it has to be decided whether the aggressive or conservative therapy is to prefer.
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PMID:[The treatment of deep venous thrombosis. Thrombolysis vs heparin]. 209 22

Once daily dosing of Enoxaparin to prevent deep vein thrombosis (DVT) after total hip replacement has been defined through two double-blind prospective, randomized multicentric trials. A previous prospective study including 228 consecutive patients had determined optimal dose to be 40 mg daily (4000 anti Xa U) begun 12 hours pre-operatively. The first trial (118 patients) compared two modes of administration of the dose of 40 mg--either 40 mg once daily or 20 mg twice daily, every twelve hours. Results were a figure of 6% for total DVT detected by ascending bilateral phlebography, 5% of wound hematoma and did not shown a statistically significant difference between the two modes of administration as regard tolerance. The second trial (237 patients) compared unfractionated calcic Heparin (5000 U.I. every eight hourly begun two hours before surgery) with Enoxaparin, 40 mg/day begun twelve hours before surgery. In the unfractionated Heparin group, we observed 27 total DVT (25%) 20 proximal DVT (12.5%) and one case of non fatal pulmonary embolism. In the Enoxaparin group, we observed 15 total DVT (12.5%), 9 proximal DVT (7.5%) no case pulmonary embolism. Red-cell transfusion requirements and hemoglobin levels on the third post-operative day shown a significant better tolerance in the Enoxaparin group. Theses results are coherent with those observed in the placebo controlled trial of Turpie, Levine, et al (1986). They used a dose of 30 mg twice daily (6000 anti Xa IU) begun 12/24 hours post-operatively, and observed a figure of 12% for total DVT and 4% for proximal DVT. Tolerance was the same than in the placebo group.
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PMID:[Prevention of deep vein thrombosis by enoxaparin after total hip prosthesis]. 217 35

The first, from the beginning of 1986 to September 1987 prescribing subcutaneous Heparin; the second from October 1987 to the end of 1988, prescribing a low molecular weight Heparin. There was a 2.6% incidence of pulmonary embolism and a 5.2% incidence of phlebitis in the first group (77 cases). In the second group there was a 1.54% incidence of PE and 3.08% incidence of phlebitis (65 cases). Other techniques know for decreasing the risk of thromboembolic complications were in both groups: hemodilution--locoregional anesthesia--early rising--post-op respiratory and functional physiotherapy.
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PMID:[A retrospective evaluation of venous thrombosis prevention in regulated orthopedic surgery (1986-1989) at the Saint-Germain-en-Laye hospital center]. 217 37

Several invasive and noninvasive tests are available to aid the clinician in the diagnosis of deep venous thrombosis and pulmonary embolism. Contrast venography remains the standard for diagnosing deep venous thrombosis of the lower extremity, while impedance plethysmography is sensitive, specific, and noninvasive. Compressive duplex ultrasonography is useful for deep venous thrombosis of the thigh down to the popliteal vein. The ventilation-perfusion lung scan is the most common test for diagnosing pulmonary embolism, but pulmonary angiography remains the standard. Heparin is the mainstay of treatment for deep venous thrombosis and pulmonary embolism, with an important role played by warfarin therapy.
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PMID:Venous thromboembolic disease: diagnosis and use of antithrombotic therapy. 219 12

Total knee arthroplasty patients are at high risk for deep venous thrombosis and pulmonary embolism. Prophylaxis against deep venous thrombosis and pulmonary embolism in these patients seems mandatory. Pharmacologic agents such as dextran 40, aspirin, and warfarin are effective but may be associated with significant complications such as drug reaction, bleeding, hematoma, and hemarthrosis. Heparin was not effective and was associated with significant bleeding complications. Mechanical methods such as continuous passive motion and sequential pneumatic compression stockings were without complications and seemed equal to or more effective than pharmacologic agents. Adding warfarin to mechanical methods did not seem to augment the antithromboembolic effect of the mechanical methods.
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PMID:Mechanical measures in the prophylaxis of postoperative thromboembolism in total knee arthroplasty. 222 29

271 patients with acute symptomatic deep venous thrombosis of lower limbs, confirmed by strain-gauge plethysmography and/or venography, were randomly assigned to receive intermittent subcutaneous heparin calcium or heparin sodium by continuous intravenous infusion for 6-10 days. Heparin dosage was adjusted to maintain activated partial thromboplastin time values (Thrombofax reagent) at 1.3-1.9 times the basal ones. Strain-gauge plethysmography was repeated at the end of heparin treatment, and evaluation of therapy was performed by comparing the indexes of venous hemodynamics and by assessing the incidence of pulmonary embolism and of bleeding complications. In the intravenous group, Maximal Venous Outflow (MVO) increased from 20.8 +/- 12.8 to 28.4 +/- 17.5 ml/min per 100 ml of tissue and Venous Capacitance (VC) from 1.39 +/- 0.92 to 1.94 +/- 1.0 ml/100 ml of tissue (mean +/- SD). In the subcutaneous group, MVO increased from 21.0 +/- 12.7 to 27.5 +/- 18.1 and VC from 1.60 +/- 0.86 to 2.06 +/- 1.0. The median improvement of MVO and VC were 22% and 36% respectively in the IV group and 20% and 24% in the SC group. Clinical pulmonary embolism occurred in 2 patients in the intravenous group (1 fatal) and in 4 in the subcutaneous group (1 fatal). 9 major bleeding complications occurred in the intravenous group (1 fatal) and 5 in the subcutaneous group (1 fatal). The differences were not significant at the statistical analysis. The results suggest that subcutaneous intermittent heparin has a comparable efficacy to continuous intravenous heparin in the treatment of deep venous thrombosis. To the same conclusion points an overview of the seven randomized trials which compared these treatment modalities.
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PMID:Subcutaneous vs intravenous heparin in the treatment of deep venous thrombosis--a randomized clinical trial. 227 May 31

Two cases of spinal subarachnoid haematoma occurring after spinal anaesthesia are reported. In the first case, lumbar puncture was attempted three times in a 81-year-old man; spinal anaesthesia trial was than abandoned, and the patient given a general anaesthetic. He was given prophylactic calcium heparinate soon after surgery. On the fourth day, the patient became paraparetic. Radioculography revealed a blockage between T10 and L3. Laminectomy was performed to remove the haematoma, but the patient recovered motor activity only very partially. The second case was a 67-year-old man, in whom spinal anaesthesia was easily carried out. He was also given prophylactic calcium heparinate soon after surgery. On the fourth postoperative day, pulmonary embolism was suspected. Heparin treatment was then started. Twelve hours later, lumbar and bilateral buttock pain occurred, which later spread to the neck. On the eighth day, the patient had neck stiffness and two seizures. Emergency laminectomy was carried out, which revealed a subarachnoid haematoma spreading to a level higher than T6 and below L1, with no flow of cerebrospinal fluid, and a non pulsatile spinal cord. Surgery was stopped. The patient died on the following day. Both these cases are similar to those previously reported and point out the role played by anticoagulants. Because early diagnosis of spinal cord compression is difficult, the prognosis is poor, especially in case of paraplegia.
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PMID:[Subarachnoid hematoma and spinal anesthesia]. 227 24


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