Blood pressure changes after intravenous fosphenytoin and levetiracetam in patients with acute cerebral symptoms.

To study the incidence and extent of the occasionally noted hypotension after intravenous (IV) infusions of fosphenytoin (FOS) and levetiracetam (LEV) in patients presenting with acute cerebral symptoms. Retrospective data collection of consecutive patients with acute cerebral symptoms who received IV infusions of a single dose of 750 mg or more of either fosphenytoin or levetiracetam and had documented blood pressure values in the 2h prior and the 2h after their IV infusion. More than 10 mmHg drop in the systolic, diastolic and MBP was observed in the FOS group following the IV infusion (-16.82 mmHg, -11.60 mmHg, and 13.34 mmHg, respectively). However, there was not a significant change in the MBP after LEV infusion (1.54 mmHg, 1.84 mmHg, and 1.74 mmHg for systolic, diastolic and MBP change, respectively). The difference in the systolic, diastolic and MBP changes between the two groups was statistical significant (all p values are <0.0001) after adjusting for age, clinical presentations of the patients and if they were on any antihypertensive medication in the hospital. Sixty two percent of patients who received FOS had >10 mmHg decrease in their MBP. In the LEV group, only 2 of the 50 patients (4%) had >10 mmHg decrease in their MBP. The difference in proportion of the patients with >10 mmHg drop in MBP between the two study groups is also statistically significant (p<0.001) for age, clinical presentations of the patients and if they were on any antihypertensive medication in the hospital. IV infusion of FOS in subjects presenting with acute cerebral symptoms may cause significant decreases in their blood pressure. This was not seen in patients receiving IV LEV infusions. Since maintaining adequate cerebral perfusion pressure is a key point in the management of patients with acute cerebral symptoms, the results of this study may carry a clinical impact on the management of this subgroup of patients.