Evidence-Based Practice Initiative.
Venous Thromboembolism in ICU Patients
Introduction
Most patients admitted to the ICU are unable to move about and are at high risk for developing venous thromboembolism in the form of deep vein thrombosis (DVT) or pulmonary emboli (PE). This paper is about an ongoing effort in the writer’s facility’s ICU to prevent occurrences of venous thromboembolism. Compliance with proper use of mechanical thrombo-prophylaxis, staff education and compliance played a major role in the decrease of DVT at this facility. This facility’s quality initiative and DVT/PE eradication program was towards prevention of these vulnerable at risk patients. Venous thromboembolism (VTE), manifested as either DVT or PE, is the most common preventable cause of hospital death. (SOURCE)? This paper focuses on the role the ICU nurses are playing to help track and prevent at risk patients from developing DVT/PE. Adherence to prophylaxis guidelines supported with regular interactive education, preprinted order sets, reminders, and computer support systems were significant.
Literature Review
Although there is substantial evidence that primary preventive therapy effectively reduces the risk of VTE, under-treatment, it remains a problem (Cohen et al, cited in Duggan-Keen, 2010). For patients at risk for VTE in the acute hospital care setting, studies showed that approximately 40% of at risk surgical patients and approximately 60% of at risk medical patients did not receive appropriate VTE prophylaxis (Cohen et al, cited in Duggan-Keen, 2010). The incidence of DVT in ICU patients has ranged from approximately 10% to 100% depending on the specific ICU patient population studied (Pastores, 2008). More importantly, unsuspected DVT may be present in patients before ICU admission. Unsuspected PE may account for acute episodes of hemodynamic instability or hypoxia in many mechanically ventilated patients in the ICU and may also contribute to difficulty weaning from mechanical ventilation. Autopsies in 436 critically ill patients in six studies detected PE in 7% to 27 % of patients (McLeod & Geerts, 2011). However, studies have demonstrated that ICU patients who receive both low molecular weight heparin (LMWH) and vasopressors have significantly lower anti-factor Xa activity than patients given the same dose of LMWH without vasopressors. Thus, vasopressor use contributes to poor efficacy of subcutaneous LMWH as a result of impaired peripheral perfusion and subsequent inadequate systemic bioavailability of the anticoagulant (McLeod & Geerts, 2011).
Factors necessitating change.
Deep vein thromboembolism is becoming an epidemic if not identified early. Nurses play major roles every day in patient’s life with the overwhelming increase of DVT/PE nationwide and in this ICU facility, nurses took it upon themselves to help fight this occurrence. This ICU facility had total cases of five patients with DVT and four cases of PE amongst sixty five patients sampled in a period of nine months. It became a very big concern needing action. Approximately the annual incidence of VTE in the United States is 900,000 and 100,000 Americans will die of Pulmonary embolism each year (Moores, 2008). Estimates suggest that per patient costs for deep vein thrombosis and pulmonary embolism are more than $10,000 and $16,000 respectively (Chan & Shorr, 2008). The direct cost of treating this preventable complication amounts to $1.5 billion annually (Roth-Yelinek, 2012).
Venous thromboembolism is a major cause of morbidity and mortality in patients admitted to the intensive care unit (ICU). In addition, the economic impact of VTE in treatment of non-fatal symptomatic VTE and related long-term morbidities is associated with a considerable health care burden with annual costs 6-7 times higher in patients with VTE than in the general population.
Implementation
So many strategies were employed in the ICU to reduce the incident of both DVT and PE in this facility. The presence of central venous catheters, mechanical ventilation, prolonged immobilization, pharmacologic paralysis, recent surgery or trauma, malignancy, and acquired coagulation disorders also contribute to VTE. Volunteer champions were created to track patients from admission and measures were implemented as DVT prophylactics, checklists were added in the admission database which includes DVT screenings. This facility protocol included administration of some form of DVT prophylaxis for all patients without contraindication. The DVT/PE bundle includes ultrasound Doppler as protocol to rule out DVT upon admission. Computed tomography (CT) angiography has replaced both the ventilation-perfusion scan and the pulmonary angiography as the diagnostic imaging modality of choice in patients with suspected PE. In patients with renal insufficiency, prophylactic hydration with sodium lower extremity venous ultrasonography revealing DVT may support a clinical diagnosis of PE. Included in the DVT/PE protocols were the measurement of D-dimer levels. The goal was to guide the need for diagnostic imaging in patients with low clinical probability for PE or if PE is unlikely coagulation system that commonly occurs during critical illness. All ICU nurses were educated on new DVT/PE screenings and prophylactic treatment. DVT/PE nurse champions meet for two hours once monthly to discuss outcome. A key priority to nurses is to encourage patients to mobilize as soon as possible. For patients at very high risk and unsuitable prophylactic treatments, temporary inferior vena cava filters were considered.
Results
The management of VTE in the critically ill patient admitted to the ICU can be exceedingly complex. First, the presence of multisystem organ failure, especially of the liver and kidney, may complicate decisions on anticoagulant therapy. The main treatment objectives are the prevention of recurrent PE and, in case of hemodynamic compromise, definitive therapy for DVT or PE involving removal of thrombus. Prevention of recurrent PE is accomplished with anticoagulation, placement of an inferior vena cava (IVC) filter, and mechanical thrombo-prophylaxis (graduated compression stockings or intermittent pneumatic compression devices). The data collected from random patients’ in the ICU showed that there was a 90% reduction in the incident of thromboembolism in ICU patients at this facility. Low molecular weight heparins have several advantages including improved bioavailability and lesser incidence of heparin-induced thrombocytopenia (Pastores, 2009). In ICU patients who are morbidly obese or develop renal failure, dosing of low molecular weight heparins were unpredictable and may lead to serious adverse consequences such as prolonged bleeding.
The use of graduated compression stockings (GCS) or intermittent pneumatic compression (IPC) or both is recommended for use in patients with a contraindication to anticoagulation prophylaxis. Compliance with proper use of mechanical thrombo-prophylaxis is often poor, depriving patients of the protection that it should provide. A study of 137 patients who were prescribed either GCS or IPC found adherence in only 26 % of the stocking patients and Pharmacological or mechanical thrombo-prophylaxis is cost-effective when administered to at-risk patients. Better awareness and judicious use of risk assessment models should help the attending physician to balance the risk of VTE against the potential bleeding risk. Despite the availability of pharmacological and mechanical measures to prevent VTE, prophylaxis for eligible patients in medical wards is still widely underused. Several practice audits and review showed that only 10% to 50% (with few exceptions) of the at-risk medical patients were managed according to these guidelines (Roth-Yelinek, 2011).
Standardized Guidelines.
In January 2010, the National Institute for Health and Clinical Excellence (NICE) issued a new guideline addressing the prevention of VTE in patients admitted to hospital. The latest clinical guideline on VTE prevention from the National Institute for Health and Clinical Excellence (NICE; CG92B) recommends that all patients be assessed for VTE risk on admission to hospital and then provided with preventive treatment tailored to their individual needs. The NICE guideline includes clear advice on assessing the risk of VTE according to the reason for admission and other relevant factors. Implementation of this guideline has the potential to prevent unnecessary deaths due to VTE, and to reduce long-term illnesses associated with non-fatal symptomatic VTE.
A key priority is to encourage patients to mobilize as soon as possible. Treatment options for VTE include non-pharmacological (mechanical) and pharmacological prophylaxis. For patients at very high risk and unsuitable for these options, temporary inferior vena caval filters may be considered. Once the risks of VTE and bleeding have been ascertained, the optimal course of treatment can be selected using the guideline algorithms.
Therefore, prevention of VTE in critically ill patients is effective in reducing the frequency of clinically important thrombotic events, thus preventing considerable morbidity. Better awareness and judicious use of individualized risk assessment models should help to improve the management of these complex patients. According to Chan& Shorr, (2008) approaches shown to be effective in VTE prevention include electronic alerts and clinical decision support system.
Evaluation.
Despite appropriate thrombo-prophylaxis, proximal DVT still occurs in approximately 2% of ICU patients who received prophylaxis. Studies to identify risk factors for patients who fail appropriate thrombo-prophylaxis and ways to manage patients at high risk of bleeding and thrombosis are needed.
Therefore, it is vital that efforts continue to be made to find means of preventing and managing VTE that are safer and more effective than those currently being used. All physicians and health care systems should develop tools or algorithms for appropriate prophylaxis in ICU patients. All nurses in critical care units should be educated appropriately regarding risks of venous thromboembolism. For all healthcare providers in critical units, the prevention of VTE must also be a high priority and should be a routine, daily consideration for every critically ill patient.
All ICU patients should be considered at risk for VTE and all patients should be provided anticoagulant or mechanical prophylaxis depending on bleeding risk. Consideration of specific prophylaxis should be individualized to each patient’s thrombotic and bleeding risks and this requires assessment on admission as well as daily reassessment. Mechanical thrombo-prophylaxis should generally be restricted to patients with or at high risk for bleeding. Prophylaxis should not be interrupted for procedures or surgery. To reduce the temptation to hold nighttime anticoagulant prophylaxis for procedures, anticoagulant should be given in the evening; this will safely allow surgery or other procedures to be done the next morning without missing any doses.
All members of the critical care team should be encouraged to take an active role in the implementation and daily assessment of VTE prevention and other key patient safety strategies. Low molecular weight heparins should not be interrupted at night time. Daily checklist of key ICU patient safety strategies including thrombo-prophylaxis should be maintained. Compliance should be monitored with regular audits.
References
Chan, C.M., & Shorr, A. F. (2009). Prevention of VTE in medical patients: Current evidence and recommendations. Elsevier Inc. and the American College of Chest Physicians.
Duggan-Keen, M. (2010). Reducing the risk of VTE: The new NICE clinical guideline. Nurse Prescribing. 8 (2). 589-594.
Geerts, W. H., Bergqvist, D., Pineo, G. F., et al (2008). Prevention of Venous thromboembolism The American College of Chest Physicians evidence based practice guidelines (8th ed). (6 suppl):381S-453S
McLeod, A. G., & Geerts, W. ( 2011). Venous thromboembolism prophylaxis in critically ill patients. Retrieved from http:// www. criticalcare.theclinics.com.
Moore, L. K. (2009). Prevention of VTE in hospitalized medical patients: just do it. Elsevier Inc. and the American College of Chest Physicians.
Pastores, S. M. ( 2009). Management of venous thromboembolism in the intensive care unit. Journal of Critical Care. 24, 185-194
Roth-Yelinke, B. (2012). Venous thromboembolism prophylaxis in acutely ill hospitalized medical patients: Are we undertreating our patients? European Journal of Internal medicine. 23. 236-239.