Treating obstructive sleep apnea in adults with epilepsy: a randomized pilot trial.

OBJECTIVE: Small uncontrolled series suggest that treatment of obstructive sleep apnea (OSA) in patients with epilepsy may improve seizure control. Prior to conducting a definitive randomized controlled trial, we addressed critical design issues in a pilot study. METHODS: We identified a cohort of adult patients with medically refractory epilepsy and coexisting OSA, documented by polysomnography (PSG). After an 8-week baseline period, subjects with OSA were randomized to therapeutic or sham continuous positive airway pressure (CPAP) for 10 weeks. Subjects maintained seizure calendars and antiepileptic drug dosages were held constant. RESULTS: Sixty-eight subjects with suspected OSA were enrolled and 35 subjects randomized to therapeutic CPAP (22 subjects) or sham (13 subjects) CPAP. Male gender and an elevated sleep apnea questionnaire score were predictive of OSA on PSG. Nineteen subjects in the therapeutic group and all 13 subjects in the sham group completed the trial. Baseline apnea-hypopnea index (AHI) and CPAP adherence were comparable between groups. A significant reduction in AHI was observed in the therapeutic CPAP group as compared to the sham group. Subjects, study coordinators, and principal investigators were unable to predict treatment allocation. CONCLUSIONS: This pilot study provided critical information related to study design and feasibility for planning a comprehensive trial to test the hypothesis that treating obstructive sleep apnea in patients with epilepsy improves seizure control.

Bispectral analysis during cardiopulmonary bypass: the effect of hypothermia on the hypnotic state.

STUDY OBJECTIVE: To evaluate the hypothesis that the bispectral index (BIS) is not affected by the hypothermia that is associated with cardiopulmonary bypass (CPB). DESIGN: Prospective, observational study. SETTING: Cardiac surgical operating suite of a university medical center. PATIENTS: 100 patients undergoing cardiac surgery requiring CPB. INTERVENTIONS: A constant effect site concentration of 2.2 ng/mL for fentanyl and 60 ng/mL for midazolam was maintained throughout surgery using a computer-assisted continuous infusion technique. MEASUREMENTS: The BIS value, percent isoflurane administered, predicted brain concentrations of midazolam and fentanyl, and nasopharyngeal temperature were recorded before CPB, at 15 minutes after the onset of CPB, at placement of the aortic cross-clamp, at start of rewarming, on separation from CPB, and 15 minutes after the end of CPB. Data were analyzed using a repeated-measures mixed-effects method, taking into account temperature, age, and predicted level of each anesthetic. MAIN RESULTS: A significant overall association between temperature and BIS was observed independent of patient age, predicted brain midazolam or fentanyl concentration, percent isoflurane administered, and surgical time point (p < 0.001). The BIS is estimated to decrease by 1.12 units for each degree Celsius decrease in body temperature. CONCLUSIONS: Hypothermia decreases the BIS by 1.12 units per degree Celsius decline in temperature.

Remifentanil prevents an increase in intraocular pressure after succinylcholine and tracheal intubation.

We have studied changes in intraocular pressure (IOP) in 30 patients after succinylcholine (suxamethonium) and tracheal intubation following administration of propofol 2 mg kg-1 and either remifentanil 1 microgram kg-1 (group R) or saline (group S). IOP was measured before induction, before administration of succinylcholine and the study drug, before intubation and for every 1 min after intubation for 5 min. There was a significant decrease in IOP in group R compared with group S from the time of administration of the study drugs to the end of the study (P < 0.006).