Preservation of blood pressure stability with hypertonic mannitol during hemodialysis initiation.

BACKGROUND: Intradialytic hypotensive events are common among hemodialysis patients and are associated with a variety of patient- and procedure-related factors, including intradialytic decline in plasma osmolality. Prior studies and practice have suggested that administration of osmotically active drugs may ameliorate blood pressure decline during chronic hemodialysis.
METHODS: Clinical and treatment data were collected for 102 consecutive patients requiring initiation of renal replacement therapy in 2 major teaching hospitals. Routine administration of mannitol differed according to institutional protocols, allowing its examination as the primary exposure of interest. Generalized linear models were fit to estimate associations of mannitol use during dialysis initiation with intradialytic blood pressure, as assessed by: (1) intradialytic blood pressure decline; (2) nadir intradialytic blood pressure; (3) absolute systolic blood pressure <90 mm Hg or decline >20 mm Hg.
RESULTS: Mean age was 62 years (±16), 70% were male and 44% were diabetic. Mean predialysis and nadir systolic blood pressure were 142 mm Hg (±29) and 121 mm Hg (±26), respectively. Mannitol administration was associated with a lesser decline in intradialytic blood pressure, a higher nadir blood pressure and fewer hypotensive events requiring intervention. No effect modification was evident according to diabetes or acuity of kidney disease (chronic vs. acute).
CONCLUSIONS: Mannitol administration appears to preserve hemodynamic stability during hemodialysis initiation. Randomized controlled trials are needed to confirm these findings and identify optimal management strategies to prevent intradialytic hypotension.