Blood Pressure Trends Variable with Hemodialysis: Definition and Clinical Significance

Introduction to Blood Pressure Variability

Blood pressure trends variable with hemodialysis are associated with increased cardiovascular morbidity and mortality in dialysis patients, according to the Kidney International guidelines 1, 2

Intradialytic hypotension is defined as a decrease in blood pressure during dialysis, or a nadir systolic blood pressure < 90 mmHg during treatment, occurring in 15-50% of hemodialysis treatments, and is associated with vascular access thrombosis, inadequate dialysis dose, and increased mortality 3
Intradialytic hypertension is defined as an increase in blood pressure during or immediately after dialysis, with a systolic blood pressure increase > 10 mmHg from pre- to post-dialysis, and is associated with hospitalization and mortality 4

Blood pressure in hemodialysis patients varies across multiple timeframes, including very short-term, short-term, mid-term, and long-term, which are associated with target-organ damage, cardiovascular events, and mortality in hemodialysis patients 1, 2, 3

Volume shifts during ultrafiltration contribute to blood pressure variability in hemodialysis patients, according to the Kidney International and American Journal of Kidney Diseases guidelines 2, 5
Arterial stiffness and activation of sympathetic nervous and renin-angiotensin systems also play a role in blood pressure variability in hemodialysis patients 2, 4
Volume overload is a major factor in hypertension in dialysis patients, and endothelial dysfunction and effects of erythropoietin therapy also contribute to blood pressure variability 4, 5, 6, 7

The Kidney International guidelines recommend that any symptomatic decrease in blood pressure or systolic blood pressure < 90 mmHg should prompt reassessment of blood pressure management, and that systolic blood pressure increase > 10 mmHg from pre- to post-dialysis in ≥ 4 of 6 consecutive treatments warrants evaluation of volume management 3, 4
Management considerations include ultrafiltration rate, dry-weight estimation, and antihypertensive medication timing and selection, according to the Kidney International and American Journal of Kidney Diseases guidelines 3, 4, 6

Regular assessment of pre- and post-dialysis blood pressure is recommended, as well as consideration of ambulatory blood pressure monitoring or home blood pressure measurements for better assessment of interdialytic blood pressure load, according to the Kidney International and American Journal of Kidney Diseases guidelines 2, 5
Evaluation of blood pressure patterns over time rather than isolated readings is also recommended, as well as monitoring for both hypotensive and hypertensive episodes during and after dialysis 2, 3, 4