Pathogenesis and treatment of dialysis hypotension

Abstract

Dialysis-induced hypotension (DIH) is a very serious clinical problem. It is one of the most frequent complication in renal replacement therapy which diminish patient's quality of life, and increases mortality in the dialyzed population. The main

Association of Mortality Risk with Various Definitions of Intradialytic Hypotension

“…In the study by Tisler et al, 4 patients with as few as one episode of IDH per month met the criteria for frequent IDH, potentially leaving too little separation between the exposure and control groups to detect a clinically important difference. In contrast, our study definition required that patients meet the specified IDH definition in at least 30% of baseline sessions to qualify as (+) IDH; for example, patients with 13 treatments in the LDO cohort's 4-week at-risk period had to have four IDH episodes to qualify, nearly four times the number required in the study by Tisler et al 4 Despite the plethora of IDH-related studies (a Pubmed search for IDH captured 318 articles 16 ) and common allusions to IDH being a cardiovascular risk factor, 17,18 strikingly little data exist to inform a prognostically relevant IDH definition. In publishing its IDH diagnostic criteria, the European guidelines group acknowledged that "no evidence-based recommendation regarding the definition of IDH can be given."…”

Left-Ventricular Diastolic Dysfunction as a Risk Factor for Dialytic Hypotension

“…Intradialytic hypotension not only causes discomfort and has a negative impact on health-related quality of life, but it may also adversely affect the outcome of chronic hemodialysis and thus reduce the patients’ life expectancy and favor underdialysis [6,7,8,9,10,11]. The immediate cause of intradialytic hypotension is acute central hypovolemia [3, 5]. Frank hypotension occurs when cardiovascular mechanisms do not adequately compensate for the blood volume reduction that results from the imbalance between the ultrafiltration rate and the plasma refilling rate [12].…”

“…There are two main clinical patterns of dialysis-associated hypotension: the first is episodic hypotension that typically occurs during the later stages of dialysis sessions and is generally favored by excessive weight gain, and the second is chronic persistent hypotension which affects about 10% of long-term dialysis patients [1,2,3]. Most of these latter patients experience frequent episodes of hypotension during dialysis sessions, whereas some patients have permanent hypotension with low predialysis systolic pressure (often less than 100 mm Hg) [4, 5].…”

“…Several factors contribute to dialytic hypotension. These include too rapid fluid removal in an attempt to reach dry weight, a rapid reduction in plasma osmolality (which causes extracellular water to move into cells), high interdialytic weight gain, anemia, poor nutritional status with hypoalbuminemia, autonomic neuropathy, anephric status, reduced pressor response to vasopressor agents, reduced cardiac reserve, increased arterial stiffness, impaired venous compliance, use of acetate rather than bicarbonate as dialysate buffer, ingestion of a meal immediately before or during the dialysis session, use of low sodium or high magnesium concentrations in the dialysate, and intake of anti-hypertensive medications before the dialysis session, which can impair cardiovascular stability (especially nitrate derivatives) [1,2,3,4,5, 12]. Excessive release of several endogenous vasodilatators such as nitric oxide, adrenomedullin and adenosine has been implicated in the pathogenesis of dialytic hypotension, together with an imbalance in the synthesis of the endogenous vasocontrictors endothelin and vasopressin [13,14,15,16].…”

Kognitiv svikt ved terminal nyresykdom

“…Pasienter med uttalt aterosklerose og eldre er mest utsatt for denne bivirkningen og vil også ofte vaere mer utsatt for cerebral hypoperfusjon ved blodtrykksfall (29).…”