Hemodialysis: Acute Complications – Intradialytic hypertension

Does this patient have intradialytic hypertension?

Intradialytic hypertension is defined as an intradialytic increase in the systolic blood pressure by greater or equal than 10 mmHg or the mean arterial pressure by greater or equal than 15 mmHg.

The hypertension usually develops during the second or third hour of hemodialysis after significant ultrafiltration has taken place; the increase in the blood pressure is characterized as being resistant to ultrafiltration.

Aggravation of pre-existing hypertension or development of de novo hypertension might be related to the use of erythropoiesis-stimulating agents

Symptoms vary and depend on the level of blood pressure:

  • Asymptomatic

  • Acute headache

  • Acute target organ damage as a result of malignant hypertension

    Blurred vision due to hypertensive retinopathy (retinal hemorrhage, papilledema)

    Altered mental status, cerebral infarct, intracranial hemorrhage, or seizure due to hypertensive encephalopathy

    Acute myocardial ischemia/infarction (chest pain), aortic dissection (chest pain), and acute pulmonary edema from left ventricular dysfunction (dyspnea)

What tests to perform?

  • This is a clinical diagnosis that relies on the review of the blood pressure values and the patient’s symptoms (target organ damage).

  • Laboratory tests and imaging studies that might help identify causes as well as severity assessment include:

    Hemoglobin (to exclude erythrocytosis)

    Serum calcium (to exclude hypercalcemia)

    EKG (to exclude acute myocardial infarction or arrhythmias)

    Cardiac biomarkers (CK-MB, troponin T, troponin I) if EKG abnormality or chest pain

    Bioelectrical impedance analysis (BIA) for better estimation of dry weight

    Chest x-ray if suspicion of acute aortic dissection (widening of mediastinum) or pulmonary edema from acute left ventricular dysfunction

    CT scan of the head if suspicion of cerebrovascular accident (hemorrhagic or ischemic)

How should patients with intradialytic hypertension be managed?

Acute management
  • If patient has evidence of acute target organ damage, the blood pressure should be lowered by 30% or systolic blood pressure to less than 180/110 mmHg by using intravenous hydralazine or labetalol

  • If patient is asymptomatic or has mild symptoms in the setting of a systolic blood pressure > 180/110 mmHg, short acting ACE inhibitor such as captopril is a reasonable initial approach. Other oral antihypertensive drugs that can be used include clonidine, a calcium channel blocker, or an adrenergic blocker (alpha- or beta-blockers)

  • If predialysis serum sodium level is < 140 mEq/L, dialysate sodium concentration may be decreased to minimize intradialytic sodium gain

  • If patient develops edema, increase ultrafiltration rate to optimize fluid removal (optional)

Prevention
  • Nonpharmacologic

    Adjust dry weight (BIA may be helpful to guide optimization of dry weight)

    Provide dietary counseling on sodium restriction

  • Dialysis prescription

    Adjust dialysate sodium to minimize intradialytic sodium gain (individualized dialysate sodium modeling; optional)Decrease dialysate calcium to 2.5 mEq/L

    Adjust dialysate potassium to avoid hypokalemia as it might induce vasoconstriction

    Consider frequent (short daily or nocturnal) hemodialysis if hypertension remains resistant to preventive therapies

  • Pharmacologic

    Use non-dialyzable anti-hypertensive drugs (Figure 1)

    Do not hold anti-hypertensive drugs before dialysis

    Decrease erythropoietin dose if pre-dialysis hemoglobin is higher than 11 g/dL

    Switch erythropoietin administration from intravenous to subcutaneous route

Figure 1.

Percent removed of commonly prescribed antihypertensive drugs during hemolysis.

What happens to patients with intradialytic hypertension?

There is an increased risk for hospitalization

There is a potential increased risk for mortality

How to utilize team care?

  • Nurse – Close monitoring in high-risk patients.

  • Pharmacist – Review timing, dosing, and dialyzability of anti-hypertensive medications, adherence to drug therapy, and monitor for drug-related side effects.

  • Dietitian- counsel patients on low sodium diet (2 gm/day) and fluid restriction (1 liter/day)

  • Specialist – Consider consulting cardiologist or neurologist if patient develops target organ damage such as acute myocardial infarction, acute decompensate heart failure or cerebrovascular accident

Are there clinical practice guidelines to inform decision making?

Applications

2004 Clinical practice guidelines on hypertension and anti-hypertensive agents in chronic kidney disease. (Published by National Kidney Foundation, K/DOQI)

2005 Clinical practice guidelines for cardiovascular disease in dialysis patients.(Published by National Kidney Foundation, K/DOQI)

2007 Guidelines for the management of arterial hypertension (Published by European Society of Cardiology, ESC).

Limitations – paucity of randomized controlled trials and meta-analyses on this topic.

Other considerations

ICD-10-CM diagnosis code I97.3: Postprocedural hypertension

What is the evidence?

“K/DOQI clinical practice guidelines on hypertension and antihypertensive agents in chronic kidney disease”. Am J Kidney Dis.. vol. 43. 2004. pp. S1-S290.

“K/DOQI clinical practice guidelines for cardiovascular disease in dialysis patients”. Am J Kidney Dis.. vol. 45. 2005. pp. S1-153 .

Chen, J, Gul, A, Sarnak, MJ. “Management of intradialytic hypertension: the ongoing challenge”. Semin Dial. vol. 19. 2006. pp. 141-5.

“2007 Guidelines for the management of arterial hypertension: The Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC)”. Eur Heart J.. vol. 28. 2007. pp. 1462-1536.

Locatelli, F, Cavalli, A, Tucci, B. “The growing problem of intradialytic hypertension”. Nat Rev Nephrol. vol. 6. 2010. pp. 41-48.

Peixoto, AJ, Santos, SF. “Blood pressure management in hemodialysis: what have we learned?”. Curr Opin Nephrol Hypertens.. vol. 19. 2010. pp. 561-566.

Inrig, JK. “Intradialytic hypertension: a less-recognized cardiovascular complication of hemodialysis”. Am J Kidney Dis. vol. 55. 2010. pp. 580-589.