Editorials: Assessment of Blood Pressure in Hemodialysis Patients

Abstract

It is self-evident that accurate measurement of blood pressure (BP) is essential for the diagnosis and treatment of hypertension. Patients on hemodialysis typically do not have their BP measured under standardized conditions, a source of error in the assessment of their BP. However, their are some unique sources of error involving interdialytic weight gain, occurrence of sleep apnea and consequent nocturnal hypertension, inability to take BP in both arms in patients who have hemodialysis angioaccess in the arm, and the white coat effect in these patients as well. Precise measurement of BP in hemodialysis patients requires interdialytic ambulatory BP monitoring. However, when ambulatory BP monitoring is not possible, BP obtained in the dialysis unit can be used in a qualitative sense for prediction of hypertension in these patients. A 2-week average predialysis BP of greater than 150/85 mmHg or a postdialysis BP of greater than 130/75 mmHg has at least 80% sensitivity in diagnosing hypertension. Specificity of at least 80% can be achieved if predialysis BP of greater than 160/90 mmHg or postdialysis BP of greater than 140/80 mmHg are used. However, poor agreement between hemodialysis unit BP and ambulatory BP precludes their use for the precise prediction of BP. Improving measurement techniques in the dialysis unit, averaging multiple BP values, using 20-minute postdialysis readings, or home BP monitoring can improve BP determination when interdialytic BP monitoring is not possible.

Median Intradialytic Blood Pressure Can Track Changes Evoked by Probing Dry-Weight

“…In part, these controversies have arisen because of inadequate BP assessment techniques in hemodialysis units. The accurate measurement of arterial pressure is the essential first step in managing this cardiovascular risk factor, yet the best way to diagnose hypertension among hemodialysis patients remains unknown (7,8).…”

“…There are several options available for assessment of hypertension among hemodialysis patients (7). These options include techniques to obtain BP both in and out of dialysis units (9).…”

Diagnosing Hypertension by Intradialytic Blood Pressure Recordings

“…Whereas many have suggested that blood pressure (BP) recordings are of little value in managing cardiovascular risk (3,4), others have argued that BP control is important (2,5,6). The accurate measurement of arterial pressure is the essential first step in managing this cardiovascular risk factor, yet the diagnosis of hypertension in hemodialysis patients continues to be a vexing problem (7,8).…”

Acute vs chronic volume overload on arterial stiffness in haemodialysis patients

“…Measurements immediately at the start of haemodialysis may be subject to biases from the white coat effect on blood pressure due to the anticipatory anxiety with cannulation of the fistula or graft. 11 Those measured immediately after haemodialysis may also be confounded by the incomplete intercompartmental fluid shift.…”