Brief Report - Prevention of Reperfusion Lung Injury by Lidocaine in Isolated Rat Lung Ventilated with Higher Oxygen Levels

BACKGROUND: Lidocaine, an antiarrhythmic drug has been shown to be effective against post-ischaemic reperfusion injury in heart. However, its effect on pulmonary reperfusion injury has not been investigated. AIMS: We investigated the effects of lidocaine on a postischaemic reperfused rat lung model. MATERIALS AND METHODS: Lungs were isolated and perfused at constant flow with Krebs-Henseilet buffer containing 4% bovine serum albumin, and ventilated with 95% oxygen mixed with 5% CO₂. Lungs were subjected to ischaemia by stopping perfusion for 60 minutes followed by reperfusion for 10 minutes. Ischaemia was induced in normothermic conditions. RESULTS: Postischaemic reperfusion caused significant (p < 0.0001) higher wet-to-dry lung weight ratio, pulmonary arterial pressure and peak airway pressure compared to control lungs. Lidocaine, at a dose of 5mg/ Kg b.w. was found to significantly (p < 0.0001) attenuate the increase in the wet-to-dry lung weight ratio, pulmonary arterial pressure and peak airway pressure observed in post-ischaemic lungs. CONCLUSION: Lidocaine is effective in preventing post-ischaemic reperfusion injury in isolated, perfused rat lung. (J Postgrad Med 2003;49:17-20)

Keywords
Lung ischaemia-reperfusion, lidocaine, antiarrhythmic drugs, local anaesthesia, free radical