Venous thromboembolism pertains to a serious complication that affects individuals who have spent some extensive time in lying down in bed. This disorder, presenting as either deep vein thrombosis or pulmonary embolism, may afflict both sick and healthy individuals because the symptoms are generally indistinct. Venous thromboembolism is a major human health concern because it has resulted in damage, as well as death, among individuals yet clinical research has categorized this disorder as treatable and preventable.
Unfortunately, approximately 80% of patients die from this complication because it was not considered as a major risk factor in these cases (Ryu et al. , 1998). In addition, venous thromboembolism has been observed to recur in an individual, thus resulting in a significant reduction in a person’s quality of life and a greater expense in terms of healthcare services. The obscure nature of the symptoms of venous thromboembolism is mostly due to the insensitivity and the low specificity of current available diagnostics tests.
The type of diagnostic assay thus plays a critical role in making a true diagnosis of this disorder and current estimates show that only 1% of cases are positively identified. In the United States, venous thromboembolism has caused the mortality of around 200,000 patients each year. Several risk factors are strongly associated with venous thromboembolism, including dysfunctional blood flow, as well as an escalated rate for coagulation of the blood or hypercoagulability. The thrombi, or clots, generally contain fibrin protein materials that are interspersed in platelets, which are the main cells associated with blood clotting.
Leukocytes are also commonly found intertwined in these thrombi. Small thrombi are initially developed in the lower extremities of the body and these may travel to other parts of the body by flowing with the circulating blood. Venous thrombosis occurs when a clot is lodged in a particular blood vessel and this attachment may cause changes in blood flow. The accumulation of platelets and leukocytes to the small thrombi may eventually lead to a bigger clot, thus impeding and ultimately preventing normal blood flow.
Other cases of venous thromboembolism are caused by physical trauma, wherein a fibrin nidus develops at the area wherein extreme pressure was introduced. Although fibrin nidi are very small in size, the continuous accumulation of fibrin and platelets will eventually generate a sizable clot that may confer changes in the blood flow. It is therefore important that prophylactic treatment be administered to patients in order to prevent thrombus formation and possibly death. It is a general procedure that patients with venous thromboembolism are administered with anticoagulants such as heparin of the unfractionated form.
It has been recently reported that low molecular weight heparin is more efficient than heparin because it is less likely to result in bleeding (Segal et al. , 2007). This observation has thus resulted in the replacement of unfractionated heparin for the prophylaxis of venous thromboembolism. In other hospitals, low molecular weight heparin is the recommended initial treatment for venous thromboembolism and a subsequent oral administration of anticoagulants is continued for the next few months.
In cases wherein venous thromboembolism seems to be of idiopathic origin, a prolonged administration of oral anticoagulants is conducted (Nicolaides et al. , 2006). Clinical testing has also shown that fondaparinux is as effective as low molecular weight heparin (Buller et al. , 2004). Guidelines have thus been designed to administer fondaparinux or heparin initially to patients with venous thromboembolism, but for outpatients who are not fully supervised by physician and other home-based patients with a reported shorter life expectancy, low molecular weight heparin is the preferred anticoagulant for prophylaxis.
The reason for the employment of low molecular weight heparin for patients with a short life expectancy is that healthcare professionals would suggest that these individuals prioritize their time in achieving a good quality of life instead of spending their time dealing with anticoagulation therapies. For home-based patients with recurrent venous thromboembolism, the recommended prophylactic regimen is dalteparin, which is taken for approximately six months. This intensive prophylactic treatment involves the initial dose of 200 IU/kg/day for the first month and then a lower dose such as 150 IU/kg/day for the next five months.
In cases where it involves prophylactic treatment of a cancer patient, the same dose should be administered for the entire duration that the cancer is determined to be active or for the duration of the anticancer treatment (van Dongen et al. , 2004). Pharmacological analyses of low molecular weight heparin have indicated these anticoagulants are entirely unique in terms of the interactions and dynamics in the body hence it is important that the same subtype of heparin be administered for the entire treatment and not be arbitrarily interchanged for another subtype (Wells et al.
, 2005). This suggestion is based on the need for more intensive toxicity testing of low molecular weight heparin during clinical trials. It has also been recommended that the same low molecular weight heparin from a specific manufacturer be used for the entire treatment because different pharmaceutical companies produce different doses of this anticoagulant, hence it would be safer for the patient to adhere to the same brand of low molecular weight heparin.
It has also been described that comparison of one brand of low molecular weight heparin with another brand is not reliable and it is more risky to attempt to extrapolate readings of one brand in order to adapt to another brand. It is thus recommended that low molecular weight heparins that have been identified in evidence-based medical reports be administered to patients with venous thromboembolism. Several risk factors have been identified to help a healthcare professional to determine whether a certain patient should be given prophylactic treatment for venous thromboembolism.
It is a standard procedure to administer anticoagulants to patients who underwent orthopedic surgery. For other surgical patients of non-orthopedic nature, these individuals are classified based on their possible risk of forming thrombi and those who are at medium- or high-risk are thus given prophylactic treatment for venous thromboembolism. For hospital patients of any other acute health disorder may also be susceptible to develop venous thrombi. It has been estimated that hospitalization of a patient may increase the risk for developing venous thromboembolism by 8-fold (Heit et al.
, 2000). Specific acute illnesses that are commonly associated with extended periods of bed rest include stroke, as well as heart and respiratory diseases. These medical conditions are characterized by a significant reduction in the mobility of the patient, thus providing a great chance of developing venous thrombi. In addition, advanced age, level of obesity and inherent coagulation disorders also influence the chances of developing venous thromboembolism.
Cancer patients have been reported to be at a higher risk for venous thromboembolism than non-cancer patients and this disease has been identified as a second cause for the mortality of cancer patients. Prophylactic treatment for venous thromboembolism is thus an important procedure that should be considered when caring for hospitalized patients. This condition is both treatable and preventable and it could decrease complications among patients who are being treated for other diseases.
Although the signs and symptoms of venous thromboembolism remain elusive, a number of predictors may be employed in order to determine whether a patient should be given preventive treatment. Several evidence-based reports describe the benefits of prophylactic treatment for venous thromboembolism, as well as differences in the types of anticoagulants that may be employed for this treatment regimen.
References
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