Michel A Theard

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The cause of ischemic stroke in younger adults is undefined in as many as 35 percent of patients. We studied the prevalence of patent foramen ovale as detected by contrast echocardiography in a population of 60 adults under 55 years old with ischemic stroke and a normal cardiac examination. We compared the results with those in a control group of 100(More)
Indications for carotid endarterectomy (CEA) have been expanded recently, and a consensus statement has been made regarding these changes. However, the debate regarding the "ideal" anesthetic for CEA remains on-going. This study was designed to evaluate the actual anesthetic techniques used by anesthesiologists for CEA. A total of 426 1-page questionnaires(More)
Blood temperature at the jugular bulb was monitored in 10 patients undergoing neurovascular procedures that used induced mild hypothermia, and its correlation with surface brain, core, and peripheral temperatures was determined. The study was motivated by the difficulty encountered in directly measuring global brain temperature and the poor correlations(More)
Hypothermia for cerebral protection is usually achieved by administration of intravenous fluids at room temperature, cooling ambient air, ice packs, and a temperature-adjustable circulating water mattress. We compared cooling by conduction by using a water mattress to cool by convection by using a forced-air cooling device. Twenty patients were(More)
Neurons synthesize NO, which may act as a retrograde messenger, involved in either potentiating or depressing neuronal excitability. NO may also play a role in the cerebral vasodilatory response to increased neuronal activity (i.e., seizures). In this study, two questions were asked: (1) is NO an endogenous anticonvulsant or proconvulsant substance? and (2)(More)
The primary objective of this study was to evaluate the electrophysiologic effects of large-dose propofol, used as the sole anesthetic in patients with epilepsy. Nine patients with medically intractable complex partial epilepsy undergoing a three-stage approach to the surgical management of epilepsy were recruited. State I involved placement of the(More)
ABSTRACT: We assessed fetoplacental blood volume flow and placental resistance prospectively with Doppler sonog-raphy in 74 normal human fetuses of 19 to 42 wk gestation to determine the changes in placental perfusion with gestational age. Placental blood volume flow was assessed from the umbilical vein as the product of the mean flow velocity integral and(More)
The authors discuss the role of intravenous anesthetic agents in brain protection. The newer intravenous anesthetics, etomidate and propofol, have been proposed as neuroprotective agents. Thiopental remains the drug of choice, however, for use prior to intraoperative ischemic events. The anesthetic ketamine presents surprising similarities to other(More)
The role played by nitric oxide (NO) in modulating seizure activity and cerebral blood flow (CBF) during seizures was investigated in rats. Seizures were induced with bicuculline (a GABA antagonist, 1.2 mg kg-1, i.v.). Each animal was subjected to an initial bicuculline-induced seizure followed by treatment with either L-nitroarginine (L-NA, a NO synthase(More)
This study was designed to determine if oral clonidine or lidocaine, injected into the scalp before head-holder (H-H) insertion, would attenuate the hemodynamic effects associated with intubation and H-H placement. Thirty-four patients undergoing skull base procedures were randomized to four groups. Group 1 received clonidine 5 mcg/kg po before surgery with(More)