When to Stop Dialysis in Intradialytic Hypertension
Dialysis should NOT be routinely stopped when intradialytic hypertension occurs; instead, continue the session while implementing management strategies focused on volume removal and dry weight optimization. 1, 2
Understanding Intradialytic Hypertension
Intradialytic hypertension is defined as a systolic blood pressure increase >10 mm Hg from pre- to post-dialysis, affecting 5-15% of hemodialysis patients. 1, 3 This condition is independently associated with increased hospitalization and mortality risk comparable to severe intradialytic hypotension, making it a serious cardiovascular complication that requires management rather than session termination. 1, 3
Why Dialysis Should Continue
The blood pressure rise during dialysis reflects chronic volume overload, sympathetic nervous system overactivity, and vascular resistance surges—not an acute emergency requiring immediate cessation. 1, 4 Patients with intradialytic hypertension typically have significant chronic extracellular volume excess despite small interdialytic weight gains, meaning they need continued ultrafiltration rather than session termination. 3, 5
Immediate Management During the Session
When intradialytic hypertension is identified during a dialysis session:
Continue ultrafiltration to achieve the prescribed dry weight target, as volume removal remains the cornerstone of management even when blood pressure rises. 1, 6
Do not reduce ultrafiltration rate unless there are signs of acute volume depletion (severe cramping, symptomatic hypotension upon standing, or clinical evidence of hypovolemia). 6, 7
Monitor for symptoms rather than stopping based on blood pressure numbers alone, as the elevated post-dialysis pressure reflects the underlying pathophysiology requiring treatment. 1, 2
Post-Session Management Algorithm
After identifying intradialytic hypertension, implement the following systematic approach:
Step 1: Volume Assessment and Dry Weight Challenge
- Immediately initiate out-of-unit blood pressure measurements (home or ambulatory monitoring) to assess true interdialytic burden. 1
- Aggressively challenge and reduce dry weight over subsequent sessions (typically 4-12 weeks, potentially up to 6-12 months for patients with diabetes or cardiomyopathy). 6, 1
- Continue this gradual dry weight reduction until the intradialytic hypertension pattern normalizes or clinical signs of volume depletion appear. 1, 6
Step 2: Dialysate Modification
- Lower dialysate sodium concentration, as this is the only controlled intervention proven to interrupt the blood pressure increase during dialysis. 1, 3, 5
- Consider longer or more frequent dialysis sessions to achieve better volume control without excessive ultrafiltration rates. 1, 6
Step 3: Medication Optimization
- Prioritize nondialyzable antihypertensive agents, particularly beta-blockers with vasodilatory properties (such as carvedilol). 1, 4, 5
- Add ACE inhibitors or angiotensin receptor blockers to inhibit the renin-angiotensin-aldosterone system, as these agents cause greater regression of left ventricular hypertrophy. 1, 6
- Administer antihypertensive medications preferentially at night to reduce nocturnal blood pressure surge and minimize intradialytic hypotension risk. 1, 6
- Avoid dialyzable antihypertensive medications that may be removed during the session. 6, 8
Step 4: Dietary Intervention
- Implement strict dietary sodium restriction (2-3 g/day) with regular counseling by dietitians. 6, 1
- This reduces interdialytic fluid accumulation and allows for more effective volume control. 6
Critical Pitfalls to Avoid
Do not mistake intradialytic hypertension for a reason to stop dialysis or reduce ultrafiltration. The elevated blood pressure during dialysis reflects chronic volume overload that requires continued aggressive fluid removal, not session termination. 1, 3
Do not assume patients with small interdialytic weight gains are euvolemic. Bioimpedance spectroscopy shows these patients have significant chronic extracellular volume excess despite appearing clinically dry. 3, 5
Do not stop the dry weight probing process prematurely. Blood pressure may continue to decrease for 8 months or longer after extracellular fluid volume normalizes—this "lag phenomenon" means persistence is required. 6
When to Actually Consider Stopping Dialysis
Dialysis should only be stopped for:
- Symptomatic hypotension with systolic blood pressure <90 mm Hg despite position changes and reduced ultrafiltration rate. 2
- Severe muscle cramping unresponsive to reduced ultrafiltration rate. 6
- Clinical evidence of acute volume depletion (orthostatic symptoms, altered mental status from cerebral hypoperfusion). 6
- Other acute complications unrelated to blood pressure (chest pain, arrhythmias, access problems). 6
Elevated blood pressure alone during or after dialysis is NOT an indication to stop the session. 1, 2