Use of leukocyte depletion to decrease injury after lung preservation and rewarming ischemia: an experimental model

Area of Science:

• Cardiovascular Surgery
• Pulmonary Medicine
• Transplantation Immunology

Background:

• Maintaining optimal lung preservation temperature is crucial during the ischemic interval.
• Lung rewarming during implantation is a common occurrence that can lead to preservation injury.
• Investigating the impact of rewarming ischemia and potential mitigation strategies is vital for improving lung transplantation outcomes.

Purpose of the Study:

• To investigate the severity of rewarming ischemia on lung preservation injury.
• To explore the potential of leukocyte depletion during initial reperfusion to minimize rewarming-induced injury.

Main Methods:

• Neonatal piglet heart-lung blocks were used in four experimental groups.
• Groups included a control (no ischemia), whole blood (WB) reperfusion after 13 hours of preservation, rewarming with WB (RWB) after 12 hours preservation and 1 hour rewarming, and initial leukocyte-depleted blood reperfusion followed by WB.
• All groups were studied on an isolated, blood-perfused, working heart-lung circuit for 4 hours.

Main Results:

• The RWB group exhibited significantly lower partial pressure of arterial oxygen and lung compliance compared to controls.
• Pulmonary vascular resistance and lung wet/dry weight ratios were significantly higher in the RWB group versus controls.
• No significant differences were observed between WB or leukocyte-depleted groups and controls for measured parameters.

Conclusions:

• Rewarming ischemia during lung implantation exacerbates reperfusion injury.
• Short-term (10 minutes) leukocyte-depleted reperfusion effectively ameliorates this injury.
• Leukocyte-depleted reperfusion should be considered for clinical lung transplantation to reduce injury.