The Effect of Direct Hemoperfusion with a Polymyxin B-Immobilized Fiber Column (DHP-PMX Therapy) on Pulmonary Ischemia-Reperfusion Injury in a Canine Model

Abstract

This study evaluates the effectiveness of direct hemoperfusion with a polymyxin B-immobilized fiber column (DHP-PMX therapy) on warm ischemia-reperfusion injury of the lung using a canine mode.

Materials and Methods: Ten adult mongrel dogs weighing 13–16 kg were used. After a left thoracotomy, the left pulmonary artery and vein were clamped. The left main bronchus was also clamped and then divided, and complete ischemia of the left lung was maintained for 3 h. The left main bronchus was re-anastomosed before reperfusion of the left lung. The right pulmonary artery was ligated immediately after reperfusion of the left lung. The dogs were divided into two groups: the DHP-PMX group (n = 5, DHP-PMX was performed for 120 min, from 30 min before reperfusion to 90 min after reperfusion) and the control group (n = 5). The body temperature of the animals was maintained at 36°C–37°C during the experiment. The PaO₂/FiO₂ (P/F ratio), AaDO₂, and lt-pulmonary vascular resistance (PVR) were measured at 30, 60, 120, 180, and 240 min after reperfusion in both groups, and the two groups were compared. The water content of the lung tissues and histopathology was also analyzed. Results: The P/F ratio decreased remarkably after reperfusion in the control group, and was significantly (p <. 05) lower than that in the PMX-DHF group until 240 min after reperfusion. The AaDO₂ was significantly (p <. 05) lower in the DHP-PMX group than in the control group at 30, 60, and 120 min after reperfusion. The lt-PVR level differed significantly (p <. 05) between the two groups until 240 min after reperfusion. The water content in the control group was significantly (p <. 05) higher than that in the DHP-PMX group at 240 min after reperfusion. Lung tissues at 120 and 240 min after reperfusion were better preserved pathologically in the DHP-PMX group. Conclusion: DHP-PMX therapy reduced warm ischemia-reperfusion injury in the lung using a canine model.

KEYWORDS:

• ischemia-reperfusion injury
• lung transplantation
• endotoxin
• polymyxin B-immobilized hemoperfusion cartridge