Gradually Increased Oxygen Administration Improved Oxygenation and Mitigated Oxidative Stress after Resuscitation from Severe Hemorrhagic Shock.
BACKGROUND
The optimal oxygen administration strategy during resuscitation from hemorrhagic shock (HS) is still controversial. Improving oxygenation and mitigating oxidative stress simultaneously seem to be contradictory goals. To maximize oxygen delivery while minimizing oxidative damage, the authors proposed the notion of gradually increased oxygen administration (GIOA), which entails making the arterial blood hypoxemic early in resuscitation and subsequently gradually increasing to hyperoxic, and compared its effects with normoxic resuscitation, hyperoxic resuscitation, and hypoxemic resuscitation in severe HS.


METHODS
Rats were subjected to HS, and on resuscitation, the rats were randomly assigned to four groups (n = 8): the normoxic, the hyperoxic, the hypoxemic, and the GIOA groups. Rats were observed for an additional 1 h. Hemodynamics, acid-base status, oxygenation, and oxidative injury were observed and evaluated.


RESULTS
Central venous oxygen saturation promptly recovered only in the hyperoxic and the GIOA groups, and the liver tissue partial pressure of oxygen was highest in the GIOA group after resuscitation. Oxidative stress in GIOA group was significantly reduced compared with the hyperoxic group as indicated by the reduced malondialdehyde content, increased catalase activity, and the lower histologic injury scores in the liver. In addition, the tumor necrosis factor-α and interleukin-6 expressions in the liver were markedly decreased in the GIOA group than in the hyperoxic and normoxic groups as shown by the immunohistochemical staining.


CONCLUSIONS
GIOA improved systemic/tissue oxygenation and mitigated oxidative stress simultaneously after resuscitation from severe HS. GIOA may be a promising strategy to improve resuscitation from HS and deserves further investigation.
From the Department of Blood Products and Substitutes, Institute of Transfusion Medicine, Academy of Military Medical Sciences, Beijing, People's Republic of China.
Xin
X
Luo
Yujing
Y
Yin
Guoxing
G
You
Gan
G
Chen
Ying
Y
Wang
Jingxiang
J
Zhao
Bo
B
Wang
Lian
L
Zhao
Hong
H
Zhou
D000818:Animals; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects* / Q000502:physiology; D010100:Oxygen / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar; D012151:Resuscitation / Q000009:adverse effects / Q000379:methods*; D012720:Severity of Illness Index; D012771:Shock, Hemorrhagic / Q000378:metabolism / Q000628:therapy*
D010100:Oxygen