Download Ventricular assist devices are primarily indicated for either a one or a

During my clinical experience, it was my privilege to spend time on the transplant
unit. While there, I assisted in the care of several patients whose primary diagnosis
was congestive heart failure. As a result of their weakened heart, these patients
were provided a ventricular assist device to assist in the circulation of blood. The
ventricular assist device was certainly the highlight of my clinical experience this
semester and the purpose of this paper is to correlate the use of ventricular assist
devices with other comorbidities.
Ventricular assist devices are primarily indicated for either a one or a combination
of several factors. These factors include destination therapy, bridge to transplant,
bridge to recovery, and eligibility for transplant. Most often, congestive heart failure
is the causative force that necessitates the placement of a VAD. Congestive heart
failure can be defined as an inability of the heart to generate an adequate cardiac
output to perfuse vital tissues. Cardiac output is dependent upon heart rate and
stroke volume. Stroke volume is influenced by three major determinants:
contractility, preload, and afterload. Any disease that disrupts the activity of the
myocyte reduces contractility. Ejection fraction is the measurement used to
quantify the force by which the heart is pumping blood. Normal ejection fraction
ranges from 55 – 70%. This means that up to 70% of the total circulating blood
volume is forced out through the left ventricle after one contraction. For one of the
patients that I cared for, contractility was so diminished (ejection fraction of 15%)
that continuous inotrope infusion was necessary to maintain a viable ejection
fraction. CHF affects nearly 10% of individuals older than age 65. Ischemic heart
disease and hypertension are the most important predisposing risk factors of
congestive heart failure. Other risk factors include age, obesity, diabetes, renal
failure, valvular heart disease, cardiomyopathies, myocarditis, congenital heart
disease, and excessive alcohol use. Of these risk factors, my patient was diagnosed
with hypertension, coronary artery disease, and diabetes.
Some of the interventions necessary for a patient with a VAD in place are primarily
preventative in nature. The goals of therapy include the prevention of infections
and maintaining a therapeutic level of blood fluidity. Infections alone increase the
risk of a thromboembolic event, further increasing the amount of anticoagulant
therapy a patient may need (Wever-Pinzon, et al., 2012). Pharmacological choices of
anticoagulation and antiplatelet therapy recommendations vary largely, partly due
to the variance between devices. Dabigtran is a new medication recently approved
by the Food and Drug Administration. This medication is a direct thrombin
inhibitor that disrupts the clotting cascade of both free and clot-bound thrombin
(Wever-Pinzon, et al., 2012).
For the patient in my care, maintaining the balance between bleeding and thrombus
formation and preventing infections were the priority interventions. This was
accomplished through the use of aspirin and warfarin, and periodically checking
clotting times. When necessary, times of increased clotting, heparin was initiated to
return the patient to a therapeutic level of anticoagulation. Meticulous care was
practiced during the VAD driveline dressing change. The effects of infection thwart
almost every aspect of VAD therapy and the nurses’ attention to detail was
indicative of this knowledge.
Between the recommended interventions and the therapeutic measures I witnessed
during my time on the transplant unit, I noticed no gaps of care. Moreover, the
attention to detail of the nurses’ I shadowed inspired me to incorporate such
diligence within my own nursing practice. I thoroughly enjoyed my time on the unit
and learned a great deal about how caring, compassionate, and competent nurses
operate on a daily basis. I look forward to working with nurses of similar dedication
once I graduate from this program.
Bibliography
Drakos, S. G., Kfoury, A. G., Selzman, C. H., Verma, D. R., & Nanas, J. N. (2011). Left
ventricular assist device unloading effects on myocardial structure and function:
current status of the field and call for action. Current Opinions Cardiology , 26 (3),
245-255.
Wever-Pinzon, O., Stehlik, J., Kfoury, A., Terrovitis, J., Diakos, N., Charitos, C., et al.
(2012). Ventricular assist devices: Pharmacological aspects of a mechanical therapy.
Pharmacology & Therapeutics , 134 (2), 189-199.