Menu

Javascript is not activated in your browser. This website needs javascript activated to work properly.
You are here

Regional cerebral metabolic rate (positron emission tomography) during inhalation of nitrous oxide 50% in humans

Author:
  • Peter Reinstrup
  • Erik Ryding
  • Tomas G Ohlsson
  • Anders Sandell
  • K Erlandsson
  • Kaj Ljunggren
  • Leif Salford
  • Sven-Erik Strand
  • Tore Uski
Publishing year: 2008
Language: English
Pages: 66-71
Publication/Series: British Journal of Anaesthesia
Volume: 100
Issue: 1
Document type: Journal article
Publisher: Macmillan

Abstract english

BACKGROUND: Recent studies in man have shown that cerebral blood flow increases during inhalation of nitrous oxide (N2O), a finding which is believed to be a result of an increased cerebral metabolic rate (CMR). However, this has not previously been evaluated in man. METHODS: Regional CMR(glu) (rCMR(glu)) was measured three dimensionally with positron emission tomography (PET) after injection of 2-(18F)fluoro-2-deoxy-D-glucose in 10 spontaneously breathing men (mean age 31 yr) inhaling either N2O 50% in O2 30% or O2 30% in N2. RESULTS: Global CMR(glu) in young men was 27 (3) micromol 100 g(-1) min(-1) [mean (SD)]. Inhalation of N2O 50% did not change global CMR(glu) [30 (5) micromol 100 g(-1) min(-1)] significantly, but it changed the distribution of the metabolism in the brain (P<0.0001 analysis of variance). Compared with inhalation of O2 30% in N2, N2O 50% inhalation increased the metabolism in the basal ganglia [14 (17)%, P<0.05] and thalamus [22 (23) %, P<0.05]. There was a prolonged metabolic effect of N2O inhalation seen on a succeeding PET scan with oxygen-enriched air (P<0.0001) performed 1 h after the N2O administration. CONCLUSIONS: Inhalation of N2O 50% did not change global CMR(glu), but the metabolism increased in central brain structures, an effect that was still present 1 h after discontinuation of N2O.

Keywords

  • Anesthesiology and Intensive Care

Other

Published
  • ISSN: 1471-6771
Sven-Erik Strand
E-mail: sven-erik.strand [at] med.lu.se

Project manager

Systemic Radiation Therapy Group

32

Professor emeritus

Medical Radiation Physics, Lund

32