摘要AIM: To investigate the effectiveness of direct hemoperfusion with polymyxin B-immobilized fibers (DHPPMX therapy) on warm ischemia-reperfusion (I/R)injury of the small intestine.METHODS: The proximal jejunum and distal ileum of mongrel dogs were resected.Warm ischemia was performed by clamping the superior mesenteric artery (SHA) and vein (SHV) for 2 h.Blood flow to the proximal small intestine was restored 1 h after reperfusion,and the distal small intestine was used as a stoma.The experiment was discontinued 6 h after repeffusion.The dogs were divided into two groups:the DHP-PMX group (n=6,DHP-PHX was performed for 180 min; from 10 rain prior to reperfusion to 170 rain after reperfusion) and the control group (n=5).The rate pressure product (RPP),SHA blood flow,mucosal tissue blood flow,and intramucosal pH (pHi)were compared between the two groups.The serum interleukin (IL)-10 levels measured 170 min after reperfusion were also compared.RESULTS: The RPP at 6 h after reperfusion was significantly higher in the PMX group than in the control group (12174±1832 mmHg/min vs 8929±1797 mmHg/min,P ＜ 0.05).The recovery rates of the SIA blood flow at 1 and 6 h after reperfusion were significantly better in the PMX group than in the control group (61%±7% vs 44%±4%,P＜0.05,and 59%±5% vs 35%±5%,P＜0.05,respectively).The recovery rate of the mucosal tissue blood flow and the pHi levels at 6 h after reperfusion were significantly higher in the PHX group (61%±8% vs 31%±3%,P＜0.05 and 7.91±0.06 VS7.69±0.08,P＜0.05,respectively).In addition,the serum IL-10 levels just before DHP-PHX removal were significantly higher in the PHX group than in the control group (1 569±253pg/mL vs 211±40 pg/mL,P＜0.05).CONCLUSION: DHP-PMX therapy reduced warm I/R injury of the small intestine.IL-10 may play a role in inhibiting I/R injury during DHP-PHX therapy.