Response to a bolus of conivaptan in patients with acute hyponatremia after brain injury
Journal of Critical Care,
Human T et al. – Conivaptan given as a bolus can effectively treat acute hyponatremia in brain–injured patients.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 the neurosciences intensive care unit.
- Variables associated with this response were identified using linear regression.
- Median pretreatment sodium was 132mEq/L, and duration of hyponatremia before dose was 1day.
- Median natremic response was +4mEq/L (interquartile range, 2-7mEq/L), measured a median of 9hours (interquartile range, 6-12hours) after conivaptan administration.
- This was associated with significant urine output (median, 2.6L over 12hours), 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 4mEq/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.