BACKGROUND Melatonin has been shown to attenuate the reflex sympathetic increases that arise in response to orthostatic challenges. We tested the hypothesis that the attenuated sympathetic increase induced by melatonin premedication may weaken the arterial blood pressure (ABP) preserving the capability during acute hypotension, thereby altering dynamic cerebral autoregulation and causing a furt...

BACKGROUND One of the main methods for evaluation of fetal well-being is analysis of Doppler flow velocity waveform of fetal vessels. Evaluation of Doppler wave of the middle cerebral artery can predict most of the at-risk fetuses in high-risk pregnancies. In this study, we tried to determine the normal ranges and their trends during pregnancy of Doppler flow velocity indices (resistive index, ...

BACKGROUND Lateralization of cerebral blood flow and EEG activity is known to vary during cognition, sleep and waking. In spite of this, electrode placement for the cerebral state index (CSI) monitor is not specified to a particular side of the brain. This study is designed to determine if pairwise registrations differ for CSI measured simultaneously from the left or right sides of the brain. ...

Acute brain injury is associated with depressed aerobic metabolism. Below a critical mitochondrial pO2 cytochrome c oxidase, the terminal electron acceptor in the mitochondrial respiratory chain, fails to sustain oxidative phosphorylation. After acute brain injury, this ischaemic threshold might be shifted into apparently normal levels of tissue oxygenation. We investigated the oxygen dependenc...

BACKGROUND In the course of occurrence of cerebral infarction, cerebral hemorrhage and subarachnoidal hemorrhage episodes, periodicities resembling those found in the solar and geomagnetic activity were observed by Kovác and Mikulecký in 2005. OBJECTIVES To investigate putative relationships between two indices of solar activity and one index of geomagnetic activity on one side and the occurr...

Transcranial Doppler ultrasound monitoring of cerebral blood flow velocity (CBFV) was performed on 17 children (age range 8 days to 6 years) with pyogenic meningitis. Serial measurements of the peak systolic, end diastolic, mean flow velocity, and resistance index (equal to peak systolic velocity minus end diastolic velocity divided by peak systolic velocity) were obtained over the period of th...

Abstract Background Cerebral stroke is a major source of mortality and morbidity. Duplex ultrasonography used to evaluate carotid cerebral arteries. The objectives this work are study the correlation between duplex parameters with risk factors ischemic parameter as prognostic tool stroke. Methods was conducted on 100 patients presented by acute submitted history taking, medical, neurological ex...