The Relation Between Cardiac Function and Cerebral Blood Flow in Stroke Patients. 1. Effect of CO, Inhalation • The effects of CO2 inhalation were determined on 23 stroke patients with and without hypertension who underwent clinical, cardiohemodynamic, cerebral blood flow (hemispheric mean and regional), cerebral metabolic rate and cerebral angiographical studies. Cardiac output, heart rate, sy...

The Effect of Carbon Dioxide Inhalation on Cerebral Blood Flow: A Two-Hour Duration Study in Dogs With Microspheres • Dogs breathed one of four gas mixtures (5% CO2-95% O2, 5% CO2-95% air, 10% CO2-90% O2, and 10% CO2-90% air) for as long as two hours. Regional cerebral blood flow as well as flow in nasal, otic, pituitary and skin tissue were measured by means of 15 ± 5 // radioactively labeled ...

abstract background: dysfunction of the autonomic nervous system has long been a subject of considerable debate and a large number of studies have disclosed contradictory results. the aim of this study was to compare cerebral vasomotor reactivity in migraine with aura (mwa) patients with migraine without aura (mwo) ones. methods: ten mwa patients (7 females and 3 males mean age: 39.70 years, sd...

In 12 spontaneously breathing intubated children (9.3-25 kg), ventilatory responses to rebreathing and to the inhalation of carbon dioxide (CO2) were investigated during halothane anaesthesia for minor surgical procedures. A T-piece (Mapleson F system) was used, modified by the insertion of a pneumotachograph and a paediatric airway adaptor of an in-line capnograph in the patient limb. Exhaled ...

Neuroactive steroids modulate anxiety in experimental animals and possibly in humans. The secretion of these compounds has been found to be altered in panic disorder (PD), with such alterations having been suggested to be a possible cause or effect of panic symptomatology. Panic-like attacks can be induced in healthy individuals by administration of panicogenic agents or by physical procedures,...

More accurate methods for monitoring cerebral blood flow, oxygen, and glucose metabolism with results of their application in human volunteers are described. Subjects with various types of cerebral vascular disease showed decreased cerebral blood flow and oxygen and glucose metabolism but anaerobic glycolysis appeared to be increased. Inhalation of 100% oxygen decreased anaerobic glycolysis, an...

More accurate methods for monitoring cerebral blood flow, oxygen, and glucose metabolism with results of their application in human volunteers are described. Subjects with various types of cerebral vascular disease showed decreased cerebral blood flow and oxygen and glucose metabolism but anaerobic glycolysis appeared to be increased. Inhalation of 100% oxygen decreased anaerobic glycolysis, an...

Inhalation of low concentrations of carbon dioxide (CO2) triggers anxious behaviours in rodents via chemosensors in the amygdala, and increases anxiety, autonomic arousal and hypervigilance in healthy humans. However, it is not known whether CO2 inhalation modulates defensive behaviours coordinated by this network in humans. We examined the effect of 7.5% CO2 challenge on the defensive eye-blin...

Cerebrovascular reactivity to CO2 inhalation and voluntary hyperventilation was studied in seven normotensive subjects and nine hypertensive patients without clinical or angiographical signs of arteriosclerosis. Cerebral blood flow (CBF) was measured by the intracarotid 133Xe clearance method and calculated as the initial slope index. Three to five CBF measurements were made in each patient in ...

Cigarette smoking is associated with elevated risk of anxiety and mood disorder. Using the 7.5% carbon dioxide (CO2) inhalation model of anxiety induction, we examined the effects of smoking status and abstinence from smoking on anxiety responses. Physiological and subjective responses to CO2 and medical air were compared in smokers and non-smokers (Experiment One) and in overnight abstinent an...