Clinical case-based approach to understanding intradialytic hypotension

The approach to end-stage renal disease (ESRD) patients who develop intradi alytic hypotension (IDH) encompasses an understanding of the pathophysiolog y, appropriate dialysis prescription modification, application of newer pha rmacologic therapies, and development of strategies for prevention. Patient s should have a "minimal data set" as part of their predialysis assessment. This information is critical to prescription modifications that may help d ecrease the risk for IDH. Individuals at "high risk" for IDH should be kept to a "safe zone" for dialysis ultrafiltration (less than or equal to3% of body weight). Specific maneuvers that may decrease the risk for IDH include adjustment of the dialysate sodium or calcium concentration and dialysate temperature. The first priority for patients developing IDH should be the s tabilization of the blood pressure and improvement in the patient's symptom ology. Pharmacologic Intervention should be considered for patients who req uire repeat interventions for IDH. "At-risk" patients with a strong cardiac history should undergo an assessment of their cardiovascular status if IDH episodes occur. The use of pharmacologic therapy, ie, midodrine, alone or in combination with prescription modification, can be helpful in decreasing Interventions required for IDH. Noncompliance and high interdialytic weigh t gain in the setting of left ventricular hypertrophy (LVH) and diastolic d ysfunction can increase the risk of IDH. Assessment of antihypertensive med ications should be performed on a regular basis to determine the correct do sing schedule for patients with hypertension who develop IDH. Coronary flow reserve may be compromised in patients with LVH, adding to the risk for pe rfusion injury with low blood pressure. Increasing the dialysate calcium co ncentration may decrease the incidence of arrhythmogenicity in certain pati ents. Patients with low body temperature may benefit most from cool dialysa te. Unit personnel should be aware of the potential link between hypotensio n and the increased relative risk for death in ESRD patients. Clinical trai ning sessions on IDH risk recognition and appropriate treatment should be i mplemented within the dialysis unit. Because repeated bouts of IDH can be d isruptive to the smooth efficiency of unit operations, attention to prevent ion as well as acute intervention of IDH is important. Preventive strategie s can be developed in each unit to decrease the number of future IDH events . Considering the importance of hypotension in overall patient survival, at tention to identifying the percentage of patients in each unit who experien ce IDH and/or who present with low blood pressure (systolic < 110 mm Hg) sh ould be tracked as a quality assurance initiative. (C) 2001 by the National Kidney Foundation, Inc.