Introduction:Severe abdominal aortic constriction above the renal arteries induces arterial hypertension above the stenotic site that is the cause of cardiac hypertrophy. Previous studies have shown that high blood pressure induces myocardial oxidative stress with conflicting results. In the present study, we assessed the effects of acute hypertension on the myocardial oxidative stress an...

BACKGROUND AND PURPOSE Assessment of cerebral autoregulation has been traditionally performed with static changes in arterial blood pressure. Newer dynamic methods require the induction of sudden drops in arterial blood pressure with the sudden release of bilateral thigh cuffs. An alternative method is proposed, based on the spontaneous variability of arterial blood pressure that does not requi...

BACKGROUND When obtaining an arterial blood sample via percutaneous puncture, there is a risk of accidentally obtaining venous blood. Conventional methods of confirming arterial blood at the bedside, such as blood color and pulsatile return, can be misleading in patients with low blood pressure or hypoxemia. OBJECTIVE To determine if the arterial sampler filling time can be an accurate indic...

Lactate in the Cerebrospinal Fluid and Pressure-Flow Relationships in Canine Cerebral Circulation • In 11 dogs, lactate and pH in the cerebrospinal fluid and in the arterial and the venous blood were measured during stepwise reductions of the arterial blood pressure by controlled bleeding. Increase in lactate and decrease in pH of the cerebrospinal fluid occurred with lowering of the mean arter...

introduction blood pressure (bp) is one of the important vital signs that need to be monitored for personal healthcare. arterial blood pressure is estimated from pulse transit time (ptt). this study uses two pulse sensors to get ptt. the aim of this study was to construct an optical system and to monitor blood pressure continuously and without cuff in people with different ages. materials and m...

In the region from arterial trunks to pial arterioles anatomical characteristics of the cerebral artery as revealed by quantitative treatment of the arterial cast consist in the predominance of the length of large arterial branches over that of the arterioles. Theoretical analysis of blood pressure drop based on the above result demonstrates a large pressure drop in the region of large arterial...

mild (140 to 159/90 to 99 mmhg) or moderate (160 to 179/100 to 109 mmhg) chronic arterial hypertension does not appear to cause headache. whether moderate hypertension predisposes patients to headache at all remains controversial, but there is little evidence that it does. ambulatory blood pressure monitoring in patients with mild and moderate hypertension has shown no convincing relationship b...

An analog computer model has been developed to study the mechanism of the atrioventricular synchronization in one type of isorhythmic A-V dissociation (pattern I). The computer model simulates the following biological feedback control system: (1) the ventricular pacemaker frequency is independent of arterial blood pressure (analogous to artificial ventricular pacing); (2) the frequency of the a...

An analog computer model has been developed to study the mechanism of the atrioventricular synchronization in one type of isorhythmic A-V dissociation (pattern I). The computer model simulates the following biological feedback control system: (1) the ventricular pacemaker frequency is independent of arterial blood pressure (analogous to artificial ventricular pacing); (2) the frequency of the a...