Thromboembolism

Venous Thromboembolism

Cancer care is complicated and Cancer patients are at high risk for developing thromboembolic disease. Nursing interventions for cancer related thrombosis are critical and potentially life saving. A coordinated and proactive approach from the nurse and the physician is involved in the provision of quality care to cancer patients and in the prevention as well as the management of VTE.

Venus thromoboembolism is a serious medical condition affecting millions of people world wide with a high mortality rate. It is estimated that every year around 250,000 new cases of VTE are diagnosed in the U.S. alone of which 50,000 cases are fatal. [Susan M] There is a significant association between cancer and Venous Thromboembolism and VTE continues to be the second leading cause of death among cancer patients falling next only to mortality associated with cancer itself. [Pfizer] Clinical statistics show that active cancer is responsible for around 20% of venous thromboembolism in the general community. It is also inferred that people presenting with idiopathic thromboembolic disease have a 3 to 4 fold increase in risk for occult malignancy. Statistics also show that therapeutic interventions for cancer contribute to an increased risk for developing VTE. Particularly, it is known that post-operative cancer patients have a 2 fold increased risk for developing DVT and 3 fold increased risk for PE compared with post-operative non-cancer patients. [Scully] Life expectancy is relatively low among cancer patients with a thrombotic event compared to those without such an associated complication. Off late, there has been considerable medical attention to studying VTE as an associated complication among cancer patients. A brief overview of the pathophysiology of VTE, symptomatic management and in particular nursing intervention for cancer patients presenting with VTE would help us get a better insight into the problem.

Venous Thromboembolism

Venous thromboembolism is a common clinical condition among inpatients and has a high mortality rate. Deep vein Thrombosis and pulmonary embolism are two different manifestations of VTE. Patients present with this condition develop a clot mass with the fusion of the red blood cells, fibrin, platelets and leukocytes inside the cardiovascular system. [Susan M] Though normal blood clots that appear on the skin surface are harmless, deep vein thrombosis is dangerous as it disrupts the flow of blood to the organs. Pulmonary embolism is more serious and is the result of a dislodged clot that finds its way into the arteries of the lungs where it blocks the blood supply to lungs thereby affecting its vital function of gaseous exchange resulting in breathlessness and dizziness and sometimes even sudden death. Thrombi may be lodged either in the distal or the lobar arteries within the lungs. Alveolar hyperventilation results as an involuntary reaction but in the absence of perfusion gaseous exchange could not be normalized. This results in bronchoconstriction and hypoxemia and pulmonary hypertension. [Susan M]

Pathophysiology of VTE

It is well-known that the onset of VTE involves abnormalities in a variety of conditions such as blood clotting components, blood vessels and blood flow which are together referred to as Virchow’s triad. Conditions such as venous statis or venous obstruction pose a high risk for developing VTE. Typically, patients who are bedridden for a long period of time are more at risk for venous statis. Venous obstruction on the other hand may result due to compression by tumors and from the accumulation of thrombi developed inside the blood vessels previously. Estrogen associated hyper-coagulation is also indicated in the pathophysiology of VTE. Several studies have found the link between increased estrogen levels due to the use of oral contraceptives or hormone replacement therapy among women to have a direct relation to the onset of VTE. [Guttmacher Institute, 2001] the association of cancer and VTE is now the topic of interest among researchers as it is found that adenocarcinoma and metastatic tumors are co morbid with VTE. This makes it clear that cancer has an altering effect on the normal clotting system. [Alexander G. Turpie, 2002] However, we are still a far way from understanding the mechanisms of cancer related thrombosis.

It is also evident from several studies that plasma levels of fibrin D-dimer is very elevated among cancer patients. It is thought that activation of extrinsic coagulation system is associated with metastasis. [Dirix et.al, 2002] Molecular studies reveal an increase in production of Tissue factor (TF) and procoagulants in a cancer patient. It is understood that tumor cells produce inflammatory cytokines and chemokines. These include tissue necrosis factor and interleukins that interact with leukocytes and endothelial cells to release TF and other cellular adhesion molecules that promote venous thrombosis. [John a Heit, 2005]

Nursing Care

Of all the complications and risk factors associated with the treatment of cancer, thrombosis management presents a serious issue. Since cancer patients are at an increased risk for bleeding and associated thrombosis, nursing care for VTE is crucial. It is well-known that almost half of the Deep Vein Thrombosis cases have their origin at the operating theatre. Hence prophylaxis is essential against the development of VTE. Typical symptoms of DVT include swelling of the limbs, rise in temperature of the affected region and localized skin redness. Similarly the symptoms for PE include sudden shortness of breath, chest pain and dizziness. Since in most cases VTE is asymtomatic it is the duty of the nurses to apprise the physician in cases of suspected DVT. Statistics show that around 75% of fatal PE cases are detected only in autopsy. [Theresa Wicklin Gillespie,2005]

Nurses are uniquely positioned in identifying potential candidates for screening and preventive therapy. If suspected, patients maybe subjected to laboratory tests and venous ultrasonography. Nurses have to personally supervise both the mechanical as well as pharmacological interventions against VTE. Since being bedridden is one of the high risk factors for developing VTE, nurses can be proactive and prevent the formation of VTE by initiating early ambulation in post surgical patients. Mechanical interventions may include the use of graduated compression stockings and intermittent pneumatic compression. These mechanical interventions are aimed at increasing the speed of the blood flow in the regions and thus prevent the formation of thrombi. Frequently, limb elevation and local heat application could help relive the symptoms. Patients with catheter related thrombosis could be treated with mild anticoagulants without having the need for removal of the catheter. [Scully] Anti-coagulant therapy may be continued in patients both as a prophylactic and on a treatment basis upon advice from the physician. [Diana M. Beck, 2002] Already evidence-based guidelines are established for the management of VTE and the main pharmacological intervention begins with administering low-molecular-weight heparin (LMWH) followed up with an oral anticoagulant such as warfarin. It is documented that the prophylactic use of LMWH reduces the risk of developing VTE by 80% in postoperative patients. The use of anticoagulant such as UFH requires parenteral administration and constant laboratory monitoring as against the use of LMWH, which requires very less monitoring. Drugs such as warfarin may induce vomiting and thus affect the oral intake of other drugs. [Theresa Wicklin Gillespie, 2005]

In patients who develop contraindications due to anticoagulant therapy or those who continue to develop embolism in spite of anticoagulant therapy, oncology nurses have to promptly consult the physician and use alternative methods such as placing ‘inferior vena cava filter’ to avoid the development of pulmonary embolism. [Roxanna Boelsen, 2001] Recent research has indicated that prophylactic screening and treatment should be extended to all the patients admitted to a hospital and not just limited to the surgical patients. It is recommended that a risk factor assessment tool be implemented covering all the patients admitted in a hospital setting so that the complications arising out of VTE could be prevented and hospital costs associated with the treatment of VTE minimized. Nurses play a vital role in the implementation of such a screening process. [Race, 2007]

Conclusion

Cancer patients are at high risk for developing venous thromboembolism. Nursing interventions for cancer care and in particular for cancer related thrombosis are critical. Nurses should keep themselves abreast with the latest evidence-based clinical methods in order to provide optimal care for cancer patients with VTE or in preventing the onset of VTE among cancer patients. Oncology nurses are also responsible for educating the patients about the risk factors, symptoms and the treatment and treatment related developments involved in VTE care. Post operative prophylaxis is particularly significant as around 80% of risk for VTE can be reduced if appropriate interventions are administered on a prophylactic basis. Asides the continual monitoring of the treatment process, cancer nurses should also be proactive in their approach and participate actively in VTE screening and assessment programs. There is no question of doubt that a coordinated approach from the nurse and the physician is involved in the provision of quality care to cancer patients and in the prevention as well as the management of VTE.

Bibliography

MF Scully (2005), ‘Clinical Guide Cancer and Thrombosis’, retrieved Feb 28th 2008, at http://www.tigc.org/pdf/cancervte05.pdf

Alexander G. Turpie, (2002) ‘ABC of Antithrombotic Therapy’, British Medical Journal, available at http://www.bmj.com/cgi/content/full/325/7369/887

Pfizer, ‘NEW FRAGMIN INDICATION FIGHTS SECOND LEADING CAUSE of DEATH in CANCER PATIENTS, CANCER-ASSOCIATED THROMBOSIS’, retrieved feb 29th 2008, from, http://www.pfizer.ca/english/newsroom/press%20releases/default.asp?s=1&releaseID=160

Dirix LY,

Salgado R,

Weytjens R,

Colpaert C,

Benoy I,

Huget P, van Dam P,

Prove a,

Lemmens J,

Vermeulen P. (2002), ‘Plasma fibrin D-dimer levels correlate with tumor volume, progression rate and survival in patients with metastatic Breast Cancer’, British Journal of Cancer, http://www.ncbi.nlm.nih.gov/pubmed/11875705

John a Heit, (Sep 2005), “Cancer and Venous Thromboembolism: Scope of the Problem’, Cancer Control, Vol! 2, Supplement 1.

Diana M. Beck, (Oct 2006), ‘Venous Thromboembolism: Prophylaxis: Implications for Medical Surgical Nurses,”

MEDSURG Nursing — October 2006 — Vol. 15/No. 5, Available online at, http://www.medsurgnursing.net/ceonline/2008/article10282288.pdf

Race, Tara Kay BSN, RN, CCRN; Collier, Paul E. MD, (July-Sep 2007), ‘The Hidden Risk of Deep Vein Thrombosis — the Need for Risk Factor Assessment: Case Reviews.’, Critical Care Nursing Quarterly, 30(3):245-254

Susan Begelman MD, ‘Venous Thromboembolism’, Retrieved 29th Feb 2008, from, ‘ http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/cardiology/vthromboembolism/vthromboembolism.htm

Roxanna Boelsen, RN, MS, AOCN, (2001), ‘Clinical Focus: Deep Vein Thrombosis’, Vol 5, No 4, Clinical Journal of Oncology Nursing. Available online at, http://www.ons.org/publications/journals/cjon/Volume5/Issue4/0504167.asp

Theresa Wicklin Gillespie (2005), ‘Nursing Interventions in the management of patients with cancer associated Thrombosis’, Seminars in Oncology Nursing, Volume 21 • Number 4 Suppl 1

http://www.nursingconsult.com/das/journal/view/89228769-2/N/15915438?issn=07492081&ja=516086&ANCHOR=text&PAGE=1.html

Guttmacher Institute, (June 2001), ‘Most Refined Analysis to Date Confirms Link Between Third-Generation Pills and Venous Thromboembolism’, Family Planning Perspectives, Volume 33, Number 3 http://www.guttmacher.org/pubs/journals/3313301.html