Effect of loxapine on electrical brain activity, intracranial pressure, and middle cerebral artery flow velocity in traumatic brain-injured patients.

ABSTRACT

INTRODUCTION: Delirium is a frequent complication of traumatic brain injury, especially during the weaning period. Antipsychotic drugs are often used in this case. Loxapine is a tricyclic antipsychotic drug with sedating properties. The effects of intravenous loxapine on EEG as well as on systemic and cerebral hemodynamics after traumatic brain injury are unknown. METHODS: Seven sedated and mechanically ventilated traumatic brain injured patients were studied 11 +/- 5 days after trauma. They were on continuous perfusion of sufentanil and midazolam. Left and right spectral edge frequency (SEFl, SEFr) of continuous EEG recording, intracranial pressure (ICP), mean flow velocity of the middle cerebral artery (MFV(MCA)) and mean arterial pressure (MAP) were simultaneously recorded and digitalized before and after loxapine infusion (10 mg in 10 min of continuous infusion). RESULTS: Loxapine induced no significant change on MAP, MFV. On the contrary, it decreased ICP and both SEFl, SEFr. ETCO(2 )and the dose of vasopressors were not altered during the study period. CONCLUSION: 10 mg of loxapine administered intravenously over 10 min decreased brain electrical activity. There is a concomitant reduction in ICP without any significant change in cerebral blood flow velocity. The use of intravenous loxapine to control agitation is not accompanied by deleterious hemodynamic or systemic effects in ICU's traumatic brain injured patients.