Effect of dexmedetomidine on acute lung injury in patients undergoing retroperitoneal laparoscopic surgery

Objective To investigate the effect of dexmedetomidine on acute lung injury in the patients undergoing retroperitoneal laparoscopic surgery. Methods Forty patients of both sexes, aged 18-60 yr, weighing 50-80 kg, of American Society of Anesthesiologist physical statusⅠor Ⅱ, scheduled for elective retroperitoneal laparoscopic partial nephrectomy, were divided into either control group(group C, n=20)or dexmedetomidine group(group Dex, n=20)using a random number table.At 10 min before induction of anesthesia, dexmedetomidine was injected intravenously in a loading dose of 1.0 μg/kg, followed by an infusion of 0.5 μg·kg-1·h-1 throughout surgery in group Dex, and the equal volume of normal saline was given instead in group C. The patients were placed in lateral position after anesthesia, and CO2 pneumoperitoneum was induced with an intra-abdominal pressure of 12 mmHg.Before induction of anesthesia(T0), at 60 and 120 min of pneumoperitoneum(T1, 2), and at 15 and 60 min after deflation(T3, 4), peripheral venous blood samples were taken for determination of serum malondialdehyde(MDA), tumor necrosis factor-alpha(TNF-α), interleukin-6(IL-6)and Clara cell 16-kDa secretory protein(CC16)concentrations by enzyme-linked immunosorbent assay. Results Compared with the baseline at T0, the serum MDA, TNF-α, IL-6 and CC16 concentrations were significantly increased at T1-4 in group C, and the serum MDA concentrations at T3, 4, serum TNF-α and IL-6 concentrations at T1-4 and serum concentrations of CC16 at T2-4 were significantly increased in group Dex(P<0.05). Compared with group C, the serum MDA, TNF-α, and CC16 concentrations at T2-4 and serum IL-6 concentrations at T1-4 were significantly decreased in group Dex(P<0.05). Conclusion Dexmedetomidine can reduce acute lung injury in the patients undergoing retroperitoneal laparoscopic surgery. Key words: Dexmedetomidine; Pneumoperitoneum, artificial; Respiratory distress syndrome, adult