Hypothermia reduces cerebral metabolic rate and cerebral blood flow in newborn pigs

Journal Article · Thu Oct 01 04:00:00 EDT 1987 · American Journal of Physiology; (USA)

OSTI ID:7018831

Busija, D W; Leffler, C W ^[1]

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1. Univ. of Tennessee, Memphis (USA)

The authors examined effects of hypothermia on cerebral metabolic rate and cerebral blood flow in anesthetized, newborn pigs (1-4 days old). Cerebral blood flow (CBF) was determined with 15-{mu}m radioactive microspheres. Regional CBF ranged from 44 to 66 ml{center dot}min{sup {minus}1}{center dot}100 g{sup {minus}1}, and cerebral metabolic rate was 1.94 {plus minus} 0.23 ml O{sub 2}{center dot}100 g{sup {minus}1}{center dot}min{sup {minus}1} during normothermia (39{degree}C). Reduction of rectal temperature to 34-35{degree}C decreased CBF and cerebral metabolic rate 40-50%. In another group of piglets, they examined responsiveness of the cerebral circulation to arterial hypercapnia during hypothermia. Although absolute values for normocapnic and hypercapnic CBF were reduced by hypothermia and absolute values for normocapnic and hypercapnic cerebrovascular resistance were increased, the percentage changes from control in these variables during hypercapnia were similar during normothermia and hypothermia. In another group of animals that were maintained normothermic and exposed to two episodes of hypercapnia, there was no attenuation of cerebrovascular dilation during the second episode. They conclude that hypothermia reduces CBF secondarily to a decrease in cerebral metabolic rate and that percent dilator responsiveness to arterial hypercapnia is unaltered when body temperature is reduced.

• OSTI ID: 7018831
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 253:4; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

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59 BASIC BIOLOGICAL SCIENCES
ALKALI METAL ISOTOPES
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BLOOD FLOW
BLOOD PRESSURE
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
CEREBRUM
COBALT 57
COBALT ISOTOPES
DAYS LIVING RADIOISOTOPES
DOMESTIC ANIMALS
DYNAMIC FUNCTION STUDIES
ELECTRON CAPTURE RADIOISOTOPES
EVEN-ODD NUCLEI
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAMMALS
METABOLISM
MICROSPHERES
MINUTES LIVING RADIOISOTOPES
NEONATES
NERVOUS SYSTEM
NIOBIUM 95
NIOBIUM ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANS
RADIOISOTOPES
RUBIDIUM 103
RUBIDIUM ISOTOPES
SWINE
TEMPERATURE EFFECTS
TIN 113
TIN ISOTOPES
VERTEBRATES