Should chronic hemodialysis be continued when intradialytic hypertension causes systolic blood pressure to rise to 180 mm Hg?

Management of Rising Blood Pressure During Hemodialysis

Yes, hemodialysis should be continued and ultrafiltration maintained to achieve the prescribed dry weight target even when blood pressure rises from 170/80 to 180/100 mmHg during the session, as volume removal remains the cornerstone of managing intradialytic hypertension. 1

Immediate Management During This Session

Continue ultrafiltration to reach your target dry weight unless the patient develops signs of acute volume depletion (severe cramping unresponsive to reduced ultrafiltration rate, symptomatic hypotension upon standing, or clinical hypovolemia). 1, 2

• Do not reduce the ultrafiltration rate simply because blood pressure is rising, as this blood pressure pattern (intradialytic hypertension) actually indicates chronic volume overload in most cases, not volume depletion. 1, 3

• The blood pressure elevation you're observing affects 10-15% of hemodialysis patients and paradoxically signals that these patients carry significant chronic extracellular volume excess despite often having small interdialytic weight gains. 3, 4

• Only stop or reduce ultrafiltration if the patient develops acute symptoms of volume depletion - not based on the blood pressure number alone. 1, 2

Understanding the Pathophysiology

This rising blood pressure pattern is driven by an intradialytic vascular resistance surge, not by the dialysis procedure itself causing harm. 3, 5

• Patients with this pattern have been shown by bioimpedance spectroscopy to have significant chronic extracellular volume overload, even when their interdialytic weight gains appear small. 3

• The blood pressure increase extends throughout the entire interdialytic interval and is independently associated with increased hospitalization and mortality risk comparable to severe intradialytic hypotension. 1, 4

• Multiple mechanisms contribute: volume overload, sympathetic nervous system overactivity, renin-angiotensin-aldosterone system activation, endothelial dysfunction, and arterial stiffness. 1, 5

Post-Session Management Algorithm

Step 1: Volume Assessment and Dry Weight Challenge

Aggressively challenge and reduce the dry weight over subsequent sessions (typically 4-12 weeks, potentially up to 6-12 months for patients with diabetes or cardiomyopathy). 1, 2

• This is the single most important intervention, as volume control underlies most cases of blood pressure elevation in dialysis patients. 6

• 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 due to a "lag phenomenon." 1, 2

• The relationship between extracellular volume and blood pressure may be sigmoidal rather than linear, meaning blood pressure rises markedly only when autoregulatory capacity is exceeded. 6, 2

Step 2: Dialysate and Dietary Sodium Management

Lower dialysate sodium concentration to ≤140 mmol/L (ideally 135-138 mmol/L) to promote sodium removal without stimulating thirst. 2

• Implement strict dietary sodium restriction to 2-3 g/day with regular dietitian counseling to reduce interdialytic fluid accumulation. 1, 2

• There is a direct association between dialysate-to-serum sodium gradients and blood pressure increases during dialysis in patients with intradialytic hypertension. 5

• Limit interdialytic weight gain to <3% of body weight (ideally <4% of dry weight), as gains >4% markedly increase cardiovascular mortality and force unsafe ultrafiltration rates. 2

Step 3: Dialysis Prescription Optimization

Consider longer or more frequent dialysis sessions to achieve better volume control without excessive ultrafiltration rates. 1, 2

• Extending treatment time to ≥5 hours decreases ultrafiltration rates, reduces hemodynamic stress, and improves blood pressure control. 1

• Keep ultrafiltration rates ≤6 mL/kg/h to avoid acute hemodynamic instability. 2

• Reduce dialysate temperature to 35-35.5°C to lessen intradialytic symptoms without compromising delivered dialysis dose. 2

Step 4: Antihypertensive Medication Optimization

Prioritize nondialyzable antihypertensive agents, particularly beta-blockers with vasodilatory properties like carvedilol. 1, 7

• Carvedilol demonstrated lower risk of death and cardiovascular death versus placebo in hemodialysis patients with dilated cardiomyopathy, and pilot data show it reduces the frequency of intradialytic hypertension. 1, 7

• Add ACE inhibitors or angiotensin receptor blockers to inhibit the renin-angiotensin-aldosterone system, as they may reduce left ventricular mass index and preserve residual kidney function. 1

• Amlodipine reduced cardiovascular events compared with placebo in hemodialysis patients with hypertension. 1

• Administer antihypertensive medications preferentially at night to reduce nocturnal blood pressure surge and minimize intradialytic hypotension risk. 1, 2

• Avoid highly dialyzable beta-blockers (atenolol, metoprolol) in favor of nondialyzable options (propranolol, carvedilol), as nondialyzable agents preserve intradialytic protection against arrhythmias. 6

Monitoring and Follow-Up

Initiate out-of-unit blood pressure measurements immediately to assess true interdialytic burden and distinguish isolated intradialytic rises from persistently elevated interdialytic hypertension. 1, 2

• Define intradialytic hypertension as a systolic blood pressure rise >10 mmHg from pre- to post-dialysis occurring in ≥4 of 6 consecutive treatments. 1, 2

• Reassess blood pressure response after each intervention using both dialysis unit measurements and out-of-unit monitoring. 1

• Continue dry weight challenges until the intradialytic blood pressure pattern normalizes or clinical signs of volume depletion appear. 1

Critical Pitfalls to Avoid

Never stop ultrafiltration or give saline boluses simply because blood pressure is rising - this worsens extracellular fluid excess and perpetuates the hypertension cycle. 2

• Do not rely solely on antihypertensive drugs without correcting volume overload, as this strategy fails to control blood pressure adequately. 2

• Avoid continuing standard thrice-weekly dialysis in patients with recurrent intradialytic hypertension and large interdialytic weight gains, as this forces unsafe ultrafiltration rates. 2

• Do not assume the patient is at dry weight just because they lack obvious clinical signs of volume overload - bioimpedance studies show these patients consistently have hidden volume excess. 3

When to Actually Stop Dialysis

Only stop dialysis for severe muscle cramping unresponsive to reduced ultrafiltration rate, clinical evidence of acute volume depletion, or other acute complications unrelated to blood pressure (such as chest pain suggesting acute coronary syndrome, altered mental status suggesting hypertensive encephalopathy, or acute pulmonary edema). 1, 2

• Exclude hypertensive emergency by looking for acute end-organ damage when systolic/diastolic pressure is ≥180/110 mmHg. 2

• If breathlessness develops during dialysis, this most often indicates volume overload or acute heart failure, making urgent continuation of dialysis necessary despite elevated pressures. 2