Blood Pressure Management in Hemodialysis Patients
The optimal approach to manage blood pressure in hemodialysis patients requires attention to both fluid status management and appropriate antihypertensive medication selection, with predialysis and postdialysis blood pressure goals of <140/90 mmHg and <130/80 mmHg, respectively. 1, 2, 3
Assessment and Measurement Considerations
- Blood pressure should be measured with the patient seated quietly for at least 5 minutes, feet on floor, arm supported at heart level 3
- In patients who have undergone multiple vascular access procedures in both arms, blood pressure should be measured in the thighs or legs using appropriate cuff size and in the supine position 1, 2
- Home blood pressure monitoring or ambulatory blood pressure monitoring provides more accurate assessment of true blood pressure than in-center measurements 1, 2, 3
- Pre-dialysis blood pressure may overestimate true blood pressure by approximately 14/7 mmHg 3
Volume Management (First-Line Approach)
- Focus first on achieving dry weight through appropriate ultrafiltration during dialysis sessions 1, 3
- Implement strict dietary sodium restriction (2-3 g/day) with regular counseling by dietitians 1, 3
- Consider the following strategies for difficult-to-control hypertension 1:
- Increased ultrafiltration
- Longer dialysis sessions
- More frequent dialysis (>3 treatments per week)
- Intradialytic sodium modeling to minimize hypotension
Pharmacological Management
- If volume control is insufficient, initiate antihypertensive medications 1, 4
- ACE inhibitors or ARBs should be used as first-line agents because they 1, 3:
- Cause greater regression of left ventricular hypertrophy
- Reduce sympathetic nerve activity
- Reduce pulse wave velocity
- May improve endothelial function
- May reduce oxidative stress
- Beta-blockers are preferred in patients with coronary artery disease or heart failure 1, 2, 5
- Calcium channel blockers have demonstrated efficacy in reducing cardiovascular events in hemodialysis patients with hypertension 1
- Diuretics may help preserve residual kidney function and limit fluid overload in patients with residual diuresis 1
Medication Administration Considerations
- Antihypertensive drugs should be given preferentially at night to 1, 4:
- Reduce nocturnal blood pressure surge
- Minimize intradialytic hypotension
- Consider the dialyzability of medications when selecting agents 1, 3
- For patients with poor medication adherence, renally eliminated agents (such as lisinopril and atenolol) can be administered thrice weekly following hemodialysis 4, 5
Monitoring and Special Considerations
- Monitor for orthostatic hypotension, particularly in elderly patients 2
- Be cautious with excessive blood pressure reduction as a U-shaped relationship exists between blood pressure and mortality in dialysis patients 1, 3, 6
- Low predialysis systolic BP (<110 mmHg) and diastolic BP (<70 mmHg) are associated with increased mortality 6
- Evaluate for secondary causes of resistant hypertension if blood pressure remains uncontrolled despite optimal therapy 3
Common Pitfalls to Avoid
- Relying solely on predialysis or postdialysis blood pressure measurements, which correlate poorly with interdialytic ambulatory blood pressure 1
- Neglecting volume status assessment before initiating or increasing antihypertensive medications 1, 3
- Using high-dose antihypertensive medications without adequate sodium restriction 1, 7
- Failing to consider dialyzability of medications, which may lead to suboptimal blood pressure control 1, 8
- Administering antihypertensive medications immediately before dialysis, which may contribute to intradialytic hypotension 1, 4