DEMYSTIFYING VADs. Nicolle Choquette RN MN Athabasca University

Transcription

1 DEMYSTIFYING VADs Nicolle Choquette RN MN Athabasca University

2 Objectives odefine o Heart Failure o VAD o o o o Post Operative Complications Acute Long Term Nursing Interventions

3 What is Heart Failure? This occurs when the Heart cannot effectively propel enough blood through the body to meet its metabolic needs.

4 New York Heart Association Heart Failure Classification System Class I (Mild) No limitation of physical activity. Class II (Mild) Slight limitation of physical activity. Comfortable at rest, but ordinary physical activity results in fatigue, palpitation, or dyspnea. Class III (Moderate) Marked limitation of physical activity. Comfortable at rest, but less than ordinary activity causes fatigue, palpitation, or dyspnea. Class IV (Severe) Unable to carry out any physical activity without discomfort. Symptoms of cardiac insufficiency at rest. If any physical activity is undertaken, discomfort is increased.

5 If medical and surgical treatments fail for Sustained End-Stage Class IV Heart Failure, heart transplantation is the therapy of choice.

6 There is are long heart transplant wait times due to: shortage of donor hearts and increased numbers of chronic patients who qualify for heart transplants. Ventricular assist devices [VADs] were therefore developed as an alternative treatment that provides circulatory assistance to patients with end-stage heart failure.

7 What is a Ventricular Assist Device? It is an implantable mechanical pump that helps propel blood out of the heart, overcoming cardiac afterload and improving cardiac preload.

8 VADs have been mainly used as a bridge-to-recovery in acute heart failure due to cardiogenic shock. a "bridge-to-transplant" for patients on a heart transplant waiting list. a permanent bridge-to-destination therapy for patients who do not qualify for transplant.

9 Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure (REMATCH) trial Landmark trial ( ) proves benefits of heart pumps for heart failure patients compared the long term left ventricular assist device (LVAD) with maximum medical management in patients with endstage heart failure who were not candidates for heart transplantation. 90 % of the subjects improved to a NYHA functional class I,10 percent to a functional class II 70% of VAD patients lived at the 2 year marker versus 15% with medical management alone

10 Devices Where the device is positioned in the heart depends primarily on the underlying heart disease.

11 Is designed to take over the pumping function of the patient s left ventricle and transfer blood to the aorta. Blood is restored throughout the body to improve perfusion and organ function. This is the most common inserted device.

12 When pulmonary arterial resistance is high, right ventricular assistance becomes necessary. Is generally used as short-term support of the right ventricle to pump blood to the pulmonary artery.

13 Is used if both ventricles are not meeting the needs of the body by using a combination of a LVAD and a RVAD.

14 Short-term bridge to recovery up to 7 days. Allows time for definitive treatment strategy. Propulsion of blood from the left side of the heart into the aorta.

15 Three Generations of VADs 1 st generation- obsolete 2 nd generation- in the market 3 rd generation - entering the market by clinical trials.

16 Postoperative Complications Although the VAD therapy improves patient mortality and quality of life, it does come with complications such as:

17 Acute Complications Thromboembolism Hemorrhage Immune Response Multi-organ Failure Right Ventricular Failure

18 Thromboembolism 10-25% due to the contact between the device foreign surface and the patient's blood. activates immune cells and coagulation pathways, attracting platelets and complement proteins to initiate the formation of a clot. Most common areas are: cerebrovascular circulation splenic Renal visceral arteries.

19 Nursing Interventions Monitor for adequate anticoagulation therapy (PTT < 60 sec and the INR between 2.5 & 3.5). S&S emboli

20 Hemorrhage 60% of patients due to: anticoagulation prolonged surgical procedure with cardiopulmonary bypass extensive surgical dissection Hepatic dysfunction and congestion from chronic heart failure

21 If a patient requires massive blood transfusions, there is a risk of: respiratory failure due to acute respiratory distress syndrome (ARDS) compromised immune system distention to right heart contributes to a release of cytokines resulting in PHTN and RVF. elevated antibodies which can interfere with a future heart transplantation.

22 Nursing Interventions Monitor: CVP coagulation and liver function studies. increased output from chest tubes tachycardia tachypnea decreased urine output changes in mental status diaphoresis prolonged capillary refill dry mucous membranes.

23 Immune Response Device biomaterials can trigger an inflammatory response and affect host immunity. promotes proliferation of T cells which leads to cell death and may affect the patient's immunity. can also induce B cell hyper-reactivity causing an autoimmune reaction. Risk of post-transplantation organ rejection.

24 Multi-Organ Failure is the major cause of death (34.8%) many are already compromised due to advanced heart disease and prolonged hospital admission. To minimize organ failure, the implantation of the device should be optimally done before any signs of organ dysfunction.

25 Nursing Interventions Accurate VS, assessments, and laboratory. Strict infection control due to risk for immunosuppression.

26 Right Ventricular Failure Approximately 11% Imbalance between newly supported left ventricle and failing right ventricle. Myocardial stunning, ischemia, arrhythmias, and increased pulmonary vascular resistance.

27 Nursing Interventions Watch for: increasing CVP decreasing device flow empty left ventricle elevated pulmonary pressures. May require inotropes to unload RV, and pulmonary vasodilators such as nitric oxide. When medical therapy is ineffective, some of the patients may require insertion of right VAD.

28 Long Term Complications Infection malnutrition abdominal complications device failure psychosocial problems.

29 This completes my presentation of ventricular assist devices. I welcome questions or comments regarding nursing care at this time.

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