Transcript Treatment of Hypertension in Patients on Hemodialysis

Hypertension
In Hemodialysis
Patients
Dr. Shahrokh Ezzatzadegan
Department of Internal Medicine
Shiraz University of Medical Sciences
Prevalence of hypertension in chronic HD pts
50 to 60 % of hemodialysis patients
30 % of PD patients
Relationship between BP and mortality in
dialysis patients
Luther JM Kidn Int 2008;73:667-668
Mechanism of HTN
•Sodium and volume overload.
•Sympathetic nervous system activity
• Inappropriate renin secretion.
• Alteration in endothelin and nitric oxide.
• Erythropoietin therapy.
• Hyperparathyroidism.
• Other:
• Uremic toxins, Nocturnal hypoxemia and sleep disturbances
Nephrol Dial Transplant. 2004 May; 19(5):1058-68
Volume overload
• Hypervolemia is the major factor
• Achieving DW will control 60% of cases of HTN
The absence of edema does not exclude hypervolemia.
K/DOQI
Blood Pressure Goals in Hypertensive ESRD Patients
≤ 140/90 mmHg (predialysis)
≤ 130/80 mmHg (postdialysis)
When and How to measure the BP in dialysis
patients?
• Predialysis SBP overestimated mean SBP by an average of 10 mm Hg
• Postdialysis SBP underestimated mean SBP by an average of 7 mm Hg
• BP reasings over a period of 1 to 2 weeks rather than isolated
readings should be used
Home blood pressure monitoring is of greater prognostic value
than hemodialysis units recordings
Alborzi et al. CJASN 2007;2:1228-1234
Management
Management of Hypertension
• Step 1: Lifestyle modifications and control of volume status with
lifestyle modifications.
• Step 2: Control of volume status with dialysis.
• Step 3: Administration of antihypertensive drugs.
Treatment of hypertension in
patients on hemodialysis
Treatment of hypertension is often a multiple-step,
multidisciplinary process to reach KDOQI guidelines
of predialysis BP values of <140/90 mm Hg.
The key to successful treatment is patience; it often
takes 4-6 weeks to achieve results.
(This represents the lag phenomenon )
Lag period between normalisation of
ECF and optimal control of BP
DLIS etc
Chronic
volume
expansion
LAG
BP
ADMA
Vascular Na/K
ATPase
NO Synthetase
iCa++
NO
DLIS etc
ADMA
ECV
Vasoconstriction
Sustained UF & Na restriction
DLIS:digoxin-like immunoreactive substance
ADMA:asymmetric-dimethyl arginine
Treatment of Intradialytic Hypertension
The step-by-step approach
Control of volume status
• Limit interdialytic weight gain
• Achieve dry weight
• Frequent dialysis & Longer dialysis time
Agarwal R, et al. Hypertension. 2009 Mar; 53(3):500-7.
Choice of antihypertensive drugs
All classes of antihypertensive drugs can be used
in dialysis patients, with the sole exception of
diuretics, which are not commonly used because
of their lack of efficacy.
Therefore, with the exceptions of diuretics, the
criteria for drug selection are quite similar to
those used in non-dialysis patients.
Postdialysis dosing or extra doses after
HD may be necessary for certain
antihypertensive agents:
•Angiotensin converting enzyme inhibitors (ACE-I): all are
dialyzable except fosinopril
•Angiotensin receptor blockers (ARB): none are dialyzed
•B-blockers: atenolol and metoprolol are dialyzable but
labetolol and carvedilol are not
•Calcium channel blocker: amlodipine is not dialyzable
Resistant Hypertension
•The use of NSAID drugs
• Renovascular hypertension
• Increasing cysts in polysystic kidney disease
• Compliance
Peritoneal dialysis
• Patients undergoing hemodialysis
who are noncompliant and in
whom volume status and
hypertension cannot be
controlled may also benefit by
switching to peritoneal dialysis.
• Nearly all peritoneal dialysis
patients can become
normotensive with strict
adherence to volume control.
Anatomical Location of Renal Sympathetic
Nerves
• Arise from T10-L1
• Follow the renal artery to the
kidney
• Primarily lie within the
adventitia
The Journal of Clinical Hypertension. 14, pages 799–801,2012
Circulation. 2002;106:1974–1979
Bilateral nephrectomy
• May be considered in
the rare, noncompliant
individual with lifethreatening
hypertension unable to
be controlled with any
dialysis modality.
Intradialytic hypertension
• 5-15%
• Mechanism
•
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•
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Extracellular volume overload
Increased cardiac output
Changes in sodium levels
Activation of the renin–angiotensin–aldosterone system
Overactivity of the sympathetic nervous system
Endothelial cell dysfunction.
Removal of anti HTN during dialysis
Intradialytic Hypertension
• Carvedilol, which blocks endothelin-1 release, appears to be
effective in this setting.
• This was suggested by a 12-week pilot study in which the initiation of
carvedilol titrated to 50 mg twice daily was associated with a
decrease in the frequency of intradialytic hypertensive episodes from
77 to 28 percent of hemodialysis sessions.
HTN following erythropoietin
• ↑BP in 20 to 30 % of IV EPO
• SQ<IV
HTN following erythropoietin
• Intravenous administration (versus subcutaneous)
• HD> peritoneal dialysis (CAPD)
• Family history of hypertension
• Higher hemoglobin (Hb) target
• Higher EPO dose
HTN following erythropoietin
PREVENTION AND TREATMENT
• The risk of hypertension can be ameliorated by raising the Hb slowly.
• Patients who still remain hypertensive can be treated with fluid
removal and the administration of antihypertensive agents.
• The dose of erythropoietin should be reduced or discontinued for
several weeks in severe cases or when other therapeutic measures
are ineffective.
Summary
• Sodium excess and extracellular volume expansion is the major factor
in the development of hypertension.
• Lifestyle modifications is critical.
• Control of volume status (Dietary salt and fluid restriction).
• Correcting adequately volume expansion with dialysis.
• All classes of antihypertensive drugs can be used in dialysis patients