How to manage hypertension episodes in a patient with chronic kidney disease (CKD) undergoing hemodialysis (HD)?

Managing Hypertension Episodes During Hemodialysis

For hypertension episodes occurring during hemodialysis, prioritize achieving true dry weight through aggressive ultrafiltration and strict dietary sodium restriction (2 g/day) before initiating or escalating antihypertensive medications, as volume overload is the primary driver of intradialytic hypertension. 1, 2

Immediate Assessment and Volume Management

First, verify the patient is at true euvolemia by gradually reducing target dry weight by 0.1 kg per 10 kg body weight over 4-12 weeks, which reduces ambulatory blood pressure by approximately 7 mmHg. 2, 3 This is the single most important intervention, as extracellular volume expansion drives hypertension in the vast majority of hemodialysis patients. 3

Dietary and Dialysis Modifications

• Implement strict dietary sodium restriction to 2-3 g/day with intensive dietitian counseling every 3 months. 1, 2, 3
• Consider lowering dialysate sodium concentration to approximately 135 mmol/L rather than 140 mmol/L to improve volume control. 2
• Avoid high dialysate sodium concentration and sodium profiling, as these aggravate thirst, fluid gain, and hypertension. 2
• For difficult-to-control cases, increase ultrafiltration, extend dialysis session duration, or increase frequency to more than 3 treatments per week. 1, 2

Critical pitfall to avoid: Never initiate or escalate antihypertensive medications without first optimizing volume status, as this leads to suboptimal outcomes and increased risk of intradialytic hypotension. 3, 4

Pharmacological Management Algorithm

Only after 4-12 weeks of optimized volume management should you consider antihypertensive medications. 3

First-Line Agents

Beta-blockers are the preferred first-line agents for patients with coronary artery disease, prior myocardial infarction, or heart failure, as they demonstrate the strongest evidence for reducing cardiovascular mortality and heart failure hospitalizations. 3, 4

• For patients with frequent intradialytic hypotension, use dialyzable beta-blockers like atenolol or metoprolol. 4
• For patients with stable intradialytic blood pressure, use non-dialyzable agents like carvedilol, but hold before dialysis if hypotension occurs frequently. 4

Calcium channel blockers are preferred first-line agents for patients without specific cardiovascular indications, as amlodipine reduced cardiovascular events compared with placebo in randomized controlled trials of hemodialysis patients. 3, 4

Second-Line Agents

Add ACE inhibitors or ARBs if blood pressure remains uncontrolled after optimizing volume and initiating first-line agents, as they cause greater regression of left ventricular hypertrophy, reduce sympathetic nerve activity, and improve endothelial function. 1, 2, 3

• ACE inhibitors/ARBs provide additional benefits through left ventricular mass reduction and preservation of residual kidney function. 4
• Consider dialyzability when selecting specific agents: enalapril and ramipril are dialyzable, while benazepril and fosinopril are not. 1

Medication Timing Strategy

Administer antihypertensive medications preferentially at night to reduce nocturnal blood pressure surge and minimize intradialytic hypotension. 2, 3, 4

• For patients with frequent intradialytic hypotension, hold non-dialyzable agents like carvedilol before dialysis and administer after the session. 3, 4
• Dialyzable agents like atenolol can be given thrice weekly following hemodialysis in noncompliant patients. 5

Blood Pressure Targets

Target predialysis blood pressure <140/90 mmHg and postdialysis blood pressure <130/80 mmHg while avoiding targets that cause substantial orthostatic hypotension or symptomatic intradialytic hypotension. 1, 2, 3, 4

• Maintain mean arterial pressure (MAP) ≥65 mmHg during hemodialysis sessions to ensure adequate tissue perfusion. 2
• Post-dialytic drops in systolic blood pressure up to 30 mmHg are associated with improved survival, but greater decreases correlate with higher mortality. 2

Important caveat: A U-shaped relationship exists between blood pressure and mortality in dialysis patients, with excess mortality at both very low and very high blood pressures. 1 This paradoxical observation may reflect greater prevalence of systolic and diastolic dysfunction in patients with lower blood pressure. 1

Monitoring and Special Considerations

Use home blood pressure monitoring or ambulatory blood pressure monitoring rather than relying solely on predialysis or postdialysis measurements, as these correlate poorly with interdialytic ambulatory blood pressure and are better determinants of all-cause mortality. 1, 2

Intradialytic Hypertension

If systolic blood pressure rises >10 mmHg from pre- to post-dialysis in at least 4 of 6 consecutive treatments (intradialytic hypertension), perform extensive evaluation including home blood pressure monitoring and reassess dry weight before adjusting medications. 3, 4 This phenomenon affects 5-15% of hemodialysis patients and is associated with increased hospitalization and mortality. 3

Resistant Hypertension

If blood pressure remains >140/90 mmHg after achieving dry weight and using three different antihypertensive agents at adequate doses, evaluate for secondary causes of resistant hypertension. 1

• The regimen should include nearly maximal doses of at least three different pharmacological agents from ACE inhibitors, calcium antagonists, beta-blockers, antiadrenergic agents, or direct vasodilators. 1
• Consider adding minoxidil for severe resistant hypertension. 1

Additional Considerations

Erythropoietin therapy can worsen hypertension, particularly in patients with pre-existing hypertension, severe anemia, or rapid anemia correction. 2, 3

Preserve residual kidney function when possible by using large doses of potent loop diuretics (such as furosemide) in patients with residual kidney function to promote sodium and water loss, though this should be approached with caution. 2