Mechanisms and Treatment of Intradialytic Hypertension

Abstract

Background: Intradialytic hypertension is a condition where there is an increase in blood pressure (BP) from pre- to post-hemodialysis; this condition has been recently identified as an independent mortality risk factor in hypertensive hemodialysis patients. The mechanisms and management of intradialytic hypertension have been explored in numerous research studies over the past few years. Summary: Patients with intradialytic hypertension have been found to be more chronically volume overloaded compared to other hemodialysis patients, although no causal role has been established. Patients with intradialytic hypertension have intradialytic vascular resistance surges that likely explain the BP increase during dialysis. Acute intradialytic changes in endothelial cell function have been proposed as etiologies for the increase in vascular resistance, although it is unclear if endothelin-1 or some other vasoconstrictive peptide is responsible. There is an association between dialysate to serum sodium gradients and BP increase during dialysis in patients with intradialytic hypertension, although it is unclear if this is related to endothelial cell activity or acute osmolar changes. In addition to probing the dry weight of patients with intradialytic hypertension, other management strategies include lowering dialysate sodium and changing antihypertensives to include carvedilol or other poorly dialyzed antihypertensives. Key Messages: Hemodialysis patients with intradialytic hypertension have an increased mortality risk compared to patients with modest decreases in BP during dialysis. Intradialytic hypertension is associated with extracellular volume overload in addition to acute increases in vascular resistance during dialysis. Management strategies should include reevaluation of dry weight and modification of both the dialysate prescription and medication prescription.

Brain natriuretic peptide reflects individual variation in hydration status in hemodialysis patients

“…No correlation was found between BNP and blood pressure, and blood pressure did not correlate with hydration status either. In clinical assessment of hydration status, blood pressure is often used as a marker of overhydration, but although sodium retention and volume overload are considered the prominent pathogenic mechanisms of hypertension in hemodialysis patients, a number of nonvolume mediated pathways may also play important roles in the complex pathogenesis of hypertension . It has been argued that BNP cannot predict the amount of fluid to be removed, as its relationship with blood pressure is not due to volume .…”

“…In clinical assessment of hydration status, blood pressure is often used as a marker of overhydration, 50 but although sodium retention and volume overload are considered the prominent pathogenic mechanisms of hypertension in hemodialysis patients, a number of nonvolume mediated pathways may also play important roles in the complex pathogenesis of hypertension. [51][52][53] It has been argued that BNP cannot predict the amount of fluid to be removed, as its relationship with blood pressure is not due to volume. 24,27 However, our results, in line with other reports, question the use of blood pressure guided fluid management.…”

Pathogenesis and treatment of hypertension in haemodialysis patients with chronic kidney disease

“…It is of note that in the Inrig et al study [38], the change of plasma ET-1 concentration from pre-to post-haemodialysis was not different between the intradialytic hypertension patients and haemodialysis controls. So, while endothelial cell dysfunction appears to be more pronounced in intradialytic hypertension patients, the most recent research has focused on specific mechanisms, by which the endothelial cells influence intradialytic blood pressure [40].…”

Blutdruckeinstellung und -medikation

“…Ein Blutdruckanstieg während der Dialyse weist häufig auf eine Hypervo lämie, also ein inadäquat eingestelltes Trocken gewicht, hin [32,33]. Diese intradialytische Hypertonie ist mit einer erhöhten kardiovaskulären Ereignisrate verbunden und kann durch die Senkung des Trockengewichts effektiv behandelt werden [34,35]. So zeigen Daten des USRDS, das bei Patienten im Alter von über 67 Jahren, die mit der Dialysebehandlung beginnen, im Verlauf die Zahl der Antihypertensiva deutlich reduziert wird, die Vorordnung von Diuretika geht um ca.…”