Response to a bolus of conivaptan in patients with acute hyponatremia after brain injury.

Abstract

PURPOSE:

The aim of the study was to analyze the response to the vasopressin-receptor antagonist conivaptan in a large cohort of brain-injured patients with acute hyponatremia.

MATERIALS AND METHODS:

The natremic response (rise in serum sodium) to an initial bolus of conivaptan was retrospectively evaluated in 124 patients over a 3-year period in our neurosciences intensive care unit. Variables associated with this response were identified using linear regression.

RESULTS:

Median pretreatment sodium was 132 mEq/L, and duration of hyponatremia before dose was 1 day. Median natremic response was +4 mEq/L (interquartile range, 2-7 mEq/L), measured a median of 9 hours (interquartile range, 6-12 hours) after conivaptan administration. This was associated with significant urine output (median, 2.6 L over 12 hours), with degree of aquaresis associated with natremic response (regression coefficient, B = 1.8 change in sodium per liter; 95% confidence interval, 1.3-2.4; P < .001). Seventy-four patients (60%) responded with a rise of at least 4 mEq/L. Response was predicted by higher baseline urine output (B = 0.018 per mL; 0.004-0.032; P = .01) and lack of oral fluid intake (B = 2.06; 0.44-3.68; P = .01) but not tonicity of intravenous fluids or creatinine clearance.

CONCLUSIONS:

Conivaptan given as a bolus can effectively treat acute hyponatremia in brain-injured patients.

• Authors: Theresa Human, Adaeze Onuoha, Michael Diringer, Rajat Dhar
• Journal: Journal of critical care (J Crit Care) Vol. 27 Issue 6 Pg. 745.e1-5 (Dec 2012) ISSN: 1557-8615 [Electronic] United States
• PMID: 22520494 (Publication Type: Journal Article)
• Copyright: Copyright © 2012 Elsevier Inc. All rights reserved.

Chemical References

• Antidiuretic Hormone Receptor Antagonists
• Benzazepines
• conivaptan
• Sodium
• Creatinine

Topics

• Administration, Intravenous
• Adult
• Aged
• Antidiuretic Hormone Receptor Antagonists
• Benzazepines (administration & dosage, therapeutic use)
• Brain Injuries (complications)
• Creatinine (metabolism)
• Dose-Response Relationship, Drug
• Female
• Humans
• Hyponatremia (drug therapy, etiology)
• Male
• Middle Aged
• Retrospective Studies
• Sodium (therapeutic use)