Research on the oxygen partial pressure with vacuum sealing drainage in rabbits

Abstract

Objective To measure the oxygen partial pressure (PtO2) within a situation of vacuum sealing drainage (VSD) implement, and to discuss the potential mechanism of VSD alleviating skeletal muscle ischemia reperfusion (I/R) injury in rabbits. Methods Rabbits were randomly(random number) divided into three groups: sham (n=10), I/R (n=10) and I/R+VSD (n=10) groups. In the I/R group, left hind limb ischemia was induced by clamping the femoral artery and vein for 4 h, then released for 6 h, to allow reperfusion of the limb. VSD was only performed in the I/R+VSD group during the reperfusion period. All rabbits were administered a series test of PtO2 in different time points before and after reperfusion, and the left hind limb skeletal muscle and ear vein blood samples were immediately harvested for biochemical analyses, including hypoxia inducible factor 1 alpha (HIF-1α) mRNA and protein, and lactic acid (LA). One-way analysis of variance (ANOVA), Fisher’s least significant difference (LSD) test or Tamhane’s T2 test was used where appropriate to analyze the experimental results. Results The levels of PtO2 in the I/R and I/R+VSD groups were decreased after ischemia, but no significant difference was noted between the two groups (t=1.322, P=0.296). The PtO2 levels in the I/R+VSD group were less increased than those in the I/R group after reperfusion (t=2.015, P=0.046). The levels of HIF-1α mRNA and protein were increased after I/R injuries (F=10.120, P=0.002; F=36.480, P<0.01; F=6.960, P=0.015, F=4.470, P=0.035), and the levels in the I/R+VSD group were greater than those in the I/R group (t=1.799, P=0.048, t=5.911, P=0.019; t=1.878, P=0.046, t=2.609, P=0.030). The LA levels were significantly increased in the skeletal muscle and blood samples in the I/R and I/R+NPWT groups compared with those in the sham group at the final stage (F=9.540, P=0.002 and F=13.750, P<0.01), but the levels in the I/R+VSD group were less than those in the I/R group (t=2.263, P=0.040 and t=3.617, P=0.027). Conclusions Our results suggested that VSD technique decreased PtO2 in regional ischemic muscles and led to increases in HIF-1α mRNA and protein that subsequent accumulation of less LA in both of regional skeletal muscle and systemic blood circulation, which provided protection effect after I/R injury in rabbits. Key words: Trauma; Ischemia reperfusion injury; Vacuum sealing drainage; Oxygen partial pressure; Hypoxia inducible factor 1 alpha; Lactic acid