Cerebral oxygen consumption

Pluta R, Ostrowska B. 1987. Acute poisoning with triethyltin in the rat. Changes in cerebral blood flow, cerebral oxygen consumption, arterial and cerebral venous blood gases. Exp Neurol 98 67- 77. 

Rosomoff H. L. and Holaday D. A. (1954) Cerebral blood flow and cerebral oxygen consumption during hypothermia. Am. J. Physiol. 179, 85-88. 

Bering E. A. (1961) Effect of body temperature change on cerebral oxygen consumption of the intact monkey. Am. J. Physiol. 200,417-419. 

Etomidate is a nonbarbiturate hypnotic without analgesic activity and is used for induction of general anesthesia, for supplementing subpotent anesthetics such as nitrous oxide in oxygen, and for maintenance of anesthesia for short operative procedures. Etomidate lowers cerebral blood flow, and similar to ketamine, methohexital, or thiopental, also reduces cerebral oxygen consumption (see also Table 16). 

Nervous System Besides producing general anesthesia, barbiturates reduce the cerebral oxygen consumption (CMRo ) in a dose-dependent manner. As a consequence, cerebral blood flow and intracranial pressure are similarly reduced. 

ABBREVIATIONS CBF, cerebral blood flow CMR02, cerebral oxygen consumption ICP, intracranial pressure MAP, mean arterial pressure HR, heart rate CO, cardiac output RR, respiratory rate V, minute ventilation. 

Figure 4 Development of ovine cerebral oxygen consumption. Brain metabolism increases with gestation, reaching a peak after birth before falling to adult levels. (Adapted from...

Metabolic data from fetal brain studies indicate that moderate hypoxia or asphyxia can be adapted to by increases in cerebral blood flow and/or fractional oxygen extraction (15,111,135-138). Acutely, reductions in cerebral oxygen consumption are small eompared to the reduction in arterial oxygen content (34) however, during severe or prolonged asphyxia, reductions in cerebral oxygen consumption become apparent. 

Figure 8 Effects of 20-mill adenosine infusion (3 (imol/kg) into an unanesthetized, nomioxic midgestation sheep fetus in utero on cerebral oxygen delivery and consumption. While oxygen delivery did not show any significant change, cerebral oxygen consumption fell. p < 0.05, paired t-test versus preinfusion level. (From Ref 161.)...

Field D, Parer J, Auslender R, Cheek D, Baker W, Johnson J. Cerebral oxygen consumption during asphyxia in fetal sheep. J Dev Physiol 1990 14(3) 131-137. 

Jones M, Sheldon RE, Peeters LL, Meschia G, Battaglia FC, Makowski EL. Fetal cerebral oxygen consumption at different levels of oxygenation. J Appl Physiol 1977 43(6) 1080-1084. 

Nordstrom CH, Messeter K, Sundharg G, Schalen W, Werner M, Ryding E. Cerebral hlood flow, vasoreactivity, and oxygen consumption during harhiturate therapy in severe traumatic hrain lesions. J Neurosurg 1988 68(3) 424-431. 

Kety SS (1956). Human cerebral blood flow and oxygen consumption as related to aging. Journal of Chronic Disease, 3, 478-486. 

Cerebral metabolic rate declines from developmental levels and plateaus after maturation. Reliable quantitative data on the changes in cerebral circulation and metabolism in humans from the middle of the first decade of life to old age have been reported [2,39,44]. By 6 years of age, cerebral blood flow and oxygen consumption already have attained high rates, and they decline thereafter to the rates of normal young adulthood [45]. Oxygen is utilized in the brain almost entirely for the oxidation of carbohydrates [46]. The equation for the complete oxidation of glucose is ... 

Vincamine (91) is the major alkaloid of V. minor, a plant used against headache and vertigo. It exerts a sedative CNS action and produces a fall in blood pressure. The principal activity is a moderate cerebral vasodilation. Clinical studies have demonstrated that i.v. administration of 91 to humans reduces the arterial blood pressure and increases cerebral blood flow and oxygen consumption. The improved cerebral hemodynamic conditions significantly and positively affect the state of patients with advanced arteriosclerosis with beneficial effects on memory, concentration, and behavior. It has thereafter been introduced under several trade names as a pharmaceutical in many European countries (232). Vobasine (32) has been widely studied it exhibits a weak CNS depressive, analgesic, and antipyretic action (21). 

Kodaira K, Fujishiro K, Wada T, Male K, Satoi T, Tsukiyama E, Fukumoto T, Uchida T, Yamazaki S, Okamura T (1993) A study on cerebral nicotine receptor distribution, blood flow, oxygen consumption, and other metabolic activities-a study on the effects of smoking on carotid and cerebral artery blood flow. Yakubutsu Seishin Kodo 13 157-165... 

Ketamine markedly increases cerebral blood flow, oxygen consumption, and intracranial pressure. Similar to the volatile anesthetics, ketamine is a potentially dangerous drug when intracranial pressure is elevated. Although ketamine decreases the respiratory rate, upper airway muscle tone is well maintained and airway reflexes are usually preserved. 

Cerebral metabolism and oxygen utilization are decreased after thiopental administration in proportion to the degree of cerebral depression. Cerebral blood flow is also decreased, but much less so than oxygen consumption. This makes thiopental a desirable drug for use in patients with cerebral swelling (eg, head trauma, brain tumors), since intracranial pressure and blood volume are not increased (in contrast to the volatile anesthetics). 

Ketamine markedly increases cerebral blood flow, oxygen consumption, and intracranial pressure. 

Ketamine is generally administered to patients intravenously, but it is also effective when administered by intramuscular, oral, and rectal routes. The onset of action is generally short (10 to 15 minutes) but the duration of anesthesia of a single dose is long. Ketamine is the only intravenous anesthetic that produces an increase in heart rate and arterial blood pressure. It can also markedly increase cerebral blood flow, oxygen consumption, and intracranial pressure. 

Jovic, R.C., Zupanc, S. (1973). Inhihition of stimulated cerebral respiration in vitro and oxygen consumption in vivo in rats treated by cholinolytic drags. Biochem. Pharmacol. 22 1189-94. 

Jovle and Zupanc (197) measured the effects of 3-qulnuclldinyl benzllate on oxygen consumption by rets and oxygen uptake by slices of rat cerebral cortex and medulla oblongata. Subcutaneous Injections of the benzllate at 4-15 mg/kg decreased oxygen consumption by a mean of 12.11 there was no clear dose-effect relationship. Rats iriiose oxygen consumption had been Increased by a mean of 33.SZ by a small dose of soman (25 ug Injected subcutaneously) had the Increase limited to about 2Z by a subcutaneous dose of 3-qulnuclldlnyl benzllate at 15 mg/kg. 

Cerebral Respiration In Vitro and Oxygen Consumption In Vivo In Rats Treated by CSiollnolytlc Drugs. Blochem. Pharmacol. 22 1189 1194. 

Cerebral Respiration In-vltro and Oxygen Consumption In vivo In Rats Treated by Chollnolytlc Drugs. Blochem Pharmacol 22 1189-1194. 

Central nervous system. Thiopental has no analgesic activity and may be antanalgesic. It is a potent anticonvulsant. Cerebral metabolic rate of oxygen consumption (CMRO ) is reduced, which leads to cerebral vasoconstriction with a concomitant reduction in cerebral blood flow and intracranial pressure. 

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