Epidural anesthesia retards intestinal acidosis and reduces portal vein endotoxin concentrations during progressive hypoxia in rabbits.
BACKGROUND
Because it is postulated that gut is important via bacterial translocation in the development of the systemic inflammatory response and multiple organ dysfunction, the preservation of gut integrity is a therapeutic goal for physicians who care for critically ill patients. The aim of the current study was to evaluate whether epidural anesthesia prevented gut injury and subsequent translocation of endotoxin during acute progressive hypoxia in rabbits.


METHODS
After the placement of an epidural catheter, 18 male rabbits, anesthetized with buprenorphine-midazolam, were allocated randomly to two groups: 0.5% lidocaine (group E) and saline (group C) groups. The solutions (0.4 ml/kg) were injected epidurally, followed by continuous infusion (0.1 ml x kg(-1) x h(-1)) during the study period. Portal blood flow, portal endotoxin concentrations, and intramucosal pH (pHi) of the ileum were measured at baseline and during two stages of progressive hypoxia (fraction of inspired oxygen [Fio2] = 0.15 and 0.10).


RESULTS
In both study groups, the portal blood flow was preserved to a similar extent during acute hypoxia. However, pHi was reduced to a lesser extent in group E (7.33 +/- 0.12 versus 7.22 +/- 0.12 at an Fio2 of 0.15 and 7.13 +/- 0.15 versus 7.03 +/- 0.12 at an Fio2 of 0.10; mean +/- SD, P < 0.01), concurrently with lower portal endotoxin concentrations (P < 0.05) compared with group C.


CONCLUSIONS
The current study showed that epidural anesthesia slowed the progression of intestinal ischemia during acute hypoxia, subsequently preventing translocation of endotoxin through the gut mucosa.
Ai
K
K
Department of Anesthesiology and General Intensive Care Unit, Keio University School of Medicine, Tokyo, Japan.
Kotake
Y
Y
Satoh
T
T
Serita
R
R
Takeda
J
J
Morisaki
H
H
D000138:Acidosis / Q000517:prevention & control*; D000208:Acute Disease; D000767:Anesthesia, Epidural; D000818:Animals; D004731:Endotoxins / Q000097:blood*; D006439:Hemodynamics; D006863:Hydrogen-Ion Concentration; D000860:Hypoxia / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000378:metabolism*; D008297:Male; D009569:Nitric Oxide / Q000096:biosynthesis; D011169:Portal Vein / Q000737:chemistry*; D011817:Rabbits; D013152:Splanchnic Circulation
D004731:Endotoxins; D009569:Nitric Oxide