Treatment of elevated intracranial pressure with hyperosmolar therapy in patients with renal failure.

BACKGROUND: To evaluate the use of hyperosmolar therapy in the management of elevated intracranial pressure (ICP) and transtentorial herniation (TTH) in patients with renal failure and supratentorial lesions.
METHODS: Patients with renal failure undergoing renal replacement therapy treated with 23.4% saline (30-60 mL) and/or mannitol for high ICP or clinical evidence of TTH were analyzed in a retrospective cohort.
RESULTS: The primary outcome measure was reversal of TTH or ICP crisis. Secondary outcome measures were modified Rankin scale on hospital discharge, survival to hospital discharge, and adverse effects. Of 254 subjects over 7 years, 6 patients with end-stage renal disease had 11 events. All patients received a 23.4% saline bolus, along with mannitol (91%), hypertonic saline (HS) maintenance fluids (82%), and surgical interventions (n = 2). Reversal occurred in 6/11 events (55%); 2 of 6 patients survived to discharge. ICP recording of 6 TTH events showed a reduction from ICP of 41 ± 3.8 mmHg (mean ± SEM) with TTH to 20.8 ± 3.9 mmHg (p = 0.05) 1 h after the 23.4% saline bolus. Serum sodium increased from 141.4 to 151.1 mmol/L 24 h after 23.4% saline bolus (p = 0.001). No patients were undergoing hemodialysis at the time of the event. There were no cases of pulmonary edema, clinical volume overload, or arrhythmia after HS.
CONCLUSIONS: Treatment with hyperosmolar therapy, primarily 23.4% saline solution, was associated with clinical reversal of TTH and reduction in ICP and had few adverse effects in this cohort. Hyperosmolar therapy may be safe and effective in patients with renal failure and these initial findings should be validated in a prospective study.