The Relationship between Intradialytic Hypotension and Hospitalized Mesenteric Ischemia

Abstract

Background and objectives Mesenteric ischemia is a rare but devastating condition caused by insufficient blood supply to meet the demands of intestinal metabolism. In patients with ESKD, it can be difficult to diagnose and has a .70% mortality rate. Patients on hemodialysis have a high prevalence of predisposing conditions for mesenteric ischemia, but the contribution of intradialytic hypotension, a potential modifiable risk factor, has not been well described.Design, setting, participants, & measurements We used data from the US Renal Data System to identify 626 patients on hemodialysis with a hospitalized mesenteric ischemia event (cases). We selected 2428 controls in up to a 1:4 ratio matched by age, sex, black race, incident dialysis year, diabetes mellitus, coronary artery disease, and peripheral artery disease. We used six different definitions of intradialytic hypotension on the basis of prior studies, and categorized patients as having had intradialytic hypotension if $30% of hemodialysis sessions in the 30 days before the event met the specified definition. ResultsThe proportion of patients with intradialytic hypotension varied depending on its definition: from 19% to 92% of cases and 11% to 94% of controls. Cases had a higher adjusted odds (1.82; 95% confidence interval, 1.47 to 2.26) of having had intradialytic hypotension in the preceding 30 days than controls when using nadir-based intradialytic hypotension definitions such as nadir systolic BP ,90 mm Hg. To examine a potential dose-response association of intradialytic hypotension with hospitalized mesenteric ischemia, we categorized patients by the proportion of hemodialysis sessions having intradialytic hypotension, defined using the Nadir90 definition (0%, 1%-9%, 10%-29%, 30%-49%, and $50%), and found a direct association of proportion of intradialytic hypotension with hospitalized mesenteric ischemia (P-trend,0.001).Conclusions Patients with hospitalized mesenteric ischemia had significantly higher odds of having had intradialytic hypotension in the preceding 30 days than controls, as defined by nadir-based definitions.

Association of Body Composition and Intradialytic Hypotension in Hemodialysis Patients

“…Intradialytic hypotension (IDH) is a common and challenging complication which is reported to occur in 5-40% of patients with hemodialysis (HD) based on different definitions in varying populations [1][2][3]. IDH has been associated with a range of clinical and pathogenic consequences including uncomfortable symptoms, inadequate dialysis dose, vascular access thrombosis, and endorgan ischemia [4][5][6][7][8]. Flythe et al [9] found that nadir-Blood Purif 2020;49:334-340 DOI: 10.1159/000504245 based definitions of IDH were more strongly associated with mortality rather than symptoms, interventions, and intradialytic decreases of systolic blood pressure (SBP) in prevalent HD patients.…”

The relationship of volume overload and its control to hypertension in hemodialysis patients

“…Data suggest that harm begins at UF rates as low as 6 mL/h/kg . Overly rapid UF induces subclinical end‐organ hypoperfusion and hypotension, which can lead to regional myocardial hypoxia as evidenced by “stunning” on transthoracic echocardiography among other biological insults . Higher UF rates that induce intradialytic hypotension and/or patient symptoms often result in hypervolemia due to UF termination and/or saline bolus administration.…”

“…46 Overly rapid UF induces subclinical end-organ hypoperfusion and hypotension, which can lead to regional myocardial hypoxia as evidenced by "stunning" on transthoracic echocardiography among other biological insults. [47][48][49][50][51][52] Higher UF rates that induce intradialytic hypotension and/or patient symptoms often result in hypervolemia due to UF termination and/ or saline bolus administration. Furthermore, several studies have shown that a lower sodium dialysate concentration reduces IDWG, UF rates, and hypertension.…”

Timing of blood pressure medications and intradialytic hypotension

“…IDH is more frequently experienced by patients of older age, who have diabetes mellitus with autonomic dysfunction and/or cardiac comorbidities . In turn, IDH is associated with numerous adverse clinical events, including inadequate dialysis, cardiovascular morbidity and mortality, arteriovenous fistula loss, and mesenteric ischemia …”

“…3,[7][8][9] In turn, IDH is associated with numerous adverse clinical events, including inadequate dialysis, 6 cardiovascular morbidity and mortality, 8,10,11 arteriovenous fistula loss, 15 and mesenteric ischemia. 16 The 2005 K/DOQI Clinical Practice Guidelines for Cardiovascular Disease in Dialysis Patients recommend that BP medications be given preferentially at night and suggest that BP meds be discontinued prior to the scheduled dialysis session. However, the strength of the recommendation was graded level C (weak) and details on which BP medications to discontinue and for how long were not provided.…”