Factors Which Affect Cardiac Performance during Hemodialysis

Abstract

Summary Cardiac performance during hemodialysis is dependent on preexisting conditions (i.e., coronary artery disease, myocardial hypertrophy, LV compliance, anemia, hypertension, etc.) and the hemodynamic alterations caused by the dialysis procedure itself (osmotic shifts, ionized calcium changes, etc.). Clinical hemodynamic investigations of cardiac performance during uremia have been hampered by the difficulty in isolating individual parameters of ventricular function. Myocardial reserve in dialysis patients is often reduced because of antecedent ischemic disease, hypertension, and the presence of autonomic dysfunction in many patients. Rapid volume losses or gains are likely to be less well tolerated with resultant hypotensive syndromes or pulmonary edema as the result. The controlled volume loss achievable with newer dialysis machines, the use of higher dialysate sodium concentrations, and the wider availability of erythropoietin may improve the tolerance to the procedure for many patients.

Intradialytic hypertension is a marker of volume excess

“…(iii) Intradialytic hypertension may be due to activation of either sympathetic nervous system or the renin-angiotensin system, but as reviewed by Inrig, the direct evidence implicating either of these two pathways is preliminary [6]. (iv) Intradialytic BP can rise due to high calcium dialysate that increased myocardial contractility and peripheral resistance or low potassium dialysate which can lead to vasoconstriction or stimulate the sympathetic nervous system [7][8][9]. (v) Finally, the rise in BP may be due to inadequate volume removal coupled with higher dialysate sodium use [10].…”

“…Without the use of several subjective assessments, there are some simpler, more objective nutritional assessments that have been developed for use in various patients, such as hospitalized, post-operative and elderly patients. These methods include the Mini Nutritional Assessment-Short Form (MNA-SF) [7], Nutrition Risk Score (NRS) [8], Malnutrition Universal Screening Tool (MUST) [9], Malnutrition Screening Tool (MST) [10] and Geriatric Nutritional Risk Index (GNRI) [11]. The GNRI was developed as a simple method to assess nutritional condition, which utilizes only three objective parameters of body weight, height…”

The main determinants of intradialysis hypertension during dialysis in chronic hemodialysis patients; a single-center study

“…Patients with kidney failure often have no problems with the functioning of the RAS system and increase renin levels in response to it. Increases in renin are most commonly found in people with high levels of renin (13,14). However, renin's response to ultrafiltration is already unknown but unmatched in all dialysis patients (5).…”

The Effect of Dialysate Composition on Systemic Hemodynamics

“…The hemodynamic response to hemodialysis is due to a complex interplay of factors: the autonomic nervous system, myocardial reserve (both inotropic and chronotropic), changes in volume status, and dialysis procedural factors which affect osmolality and electrolytes. Previous articles in this series have reviewed the role of the autonomic nervous system and myocardial performance in determining how the individual patient will respond to volume removal ( 1,2). The following discussion will focus on the way various constituents of the dialysate influence the hemodyamic response to hemodialysis.…”

“…Directly decreases peripheral vascular resistance (in approxi-Stimulates release of the vasodilator compound, interleukin-1 Induces metabolic acidosis via bicarbonate loss through the di-Associated with arterial hypoxemia and increases in oxygen convasodilatory tendency induced by the diffusive nature of the therapy. It is unclear, however, whether inability to vasoconstrict during conventional hemodialysis is related to use of acetate or, rather, a fall in serum osmolality.…”