Inflammation increases vulnerability to hypoxia in newborn piglets: effect of reoxygenation with 21% and 100% O2.
OBJECTIVE
The purpose of this study was to assess whether inflammation increases vulnerability to hypoxia, and influences the effect of 100% O(2) and 21% O 2 reoxygenation on brain.


METHODS
Newborn piglets (n = 31) were randomized to 4 interventional groups: pretreatment with saline or endotoxin. After hypoxia they were reoxygenated with 21% or 100% oxygen for 30 minutes, followed by 21% oxygen for all groups. To assess brain injury we measured extracellular brain tissue glucose, glycerol, and lactate/pyruvate by microdialysis, brain tissue oxygen tension, and laser Doppler flow.


RESULTS
Administration of endotoxin reduced the time to reach base excess (BE) -20 mmol/L by median 32 minutes compared with saline ( P < .05). We found no differences in changes in biochemical markers, brain tissue microcirculation, or oxygen tension between piglets in the 4 groups.


CONCLUSIONS
Endotoxin and hypoxia acted synergistically in inducing metabolic acidosis. In the presence of experimental inflammation, 21% oxygen seems as effective as 100% O(2) in reoxygenating piglets.
Lyng
Kristin
K
Department of Pediatric Research, Rikshospitalet University Hospital, Oslo, Norway. kristin.lyng@klinmed.uio.no
Braakhuis
Marjolein
M
Frøen
J Frederik
JF
Stray-Pedersen
Babill
B
Saugstad
Ola Didrik
OD
D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D019540:Area Under Curve; D001783:Blood Flow Velocity; D002560:Cerebrovascular Circulation / Q000502:physiology; D004195:Disease Models, Animal; D004198:Disease Susceptibility; D002534:Hypoxia, Brain / Q000503:physiopathology* / Q000628:therapy*; D007249:Inflammation / Q000503:physiopathology*; D010100:Oxygen / Q000627:therapeutic use; D010101:Oxygen Consumption / Q000502:physiology; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D011336:Probability; D011897:Random Allocation; D012016:Reference Values; D012680:Sensitivity and Specificity; D013552:Swine
D010100:Oxygen