Increase in cerebrospinal fluid pressure in normocapnic volunteers in response to nalbuphine.

We have carried out a double-blind randomized study of the effect of nalbuphine (0.2 mg.kg-1 i.v.) or placebo on mean lumbar cerebrospinal fluid (CSF) pressure, mean cerebral perfusion pressure (CPP), transcutaneous PCO2 (tcPCO2), mean arterial blood pressure (MAP), and heart rate (HR) in 10 spontaneously breathing volunteers using invasive CSF pressure measurement. Nalbuphine increased CSF pressure from 9.2 mmHg to 16.4 mmHg and decreased CPP from 83.6 mmHg to 74.4 mmHg without significantly changing tcPCO2, MAP, or heart rate. In the placebo group there were no significant changes in CSF pressure, CPP, tcPCO2, MAP, or heart rate. These findings suggest that nalbuphine should be used with caution in patients at risk of intracranial hypertension.