Effects of remote ischemic preconditioning combined with dexmedetomidine on lung injury during perioperative period and postoperative pulmonary complications in elderly patients with thoracotomy and pulmonary dysfunction / 中华老年医学杂志

ABSTRACT

Objective To investigate the effect of remote ischemic preconditioning (RIPC) combined with dexmedetomidine on lung injury during perioperative period and postoperative pulmonary complications in elderly patients with thoracotomy and pulmonary dysfunction.Methods Sixty ASA Ⅱ or Ⅲ patients aged 65-76 years [mean (70.4±6.3) years],weighing 50-75 kg,with moderate and severe pulmonary dysfunction,who were scheduled for elective radical operation for esophageal cancer,were randomly divided into 3 groups (n=20,each) by using a random number tablethe control group (group C),RIPC group (group OR) and RIPC plus dexmedetomidine group (group ORD).At 10 min after endotracheal intubation,group ORD was induced by three cycles of 5 min of lower extremity ischemia followed by 5 min of reperfusion,at the same time a loading dose of dexmedetomidine 0.5 μig / kg was infused iv over 15 min,and then was infused at a rate of 0.5 μg · kg-1 · h-1 until the end of operation.Group OR was induced by three cycles of 5 min of lower extremity ischemia followed by 5min of reperfusion without dexmedetomidine.Group C received only the equal volume of normal saline.Blood samples were obtained from radial artery immediately before anesthesia induction (T0),before one lung ventilation (T1),at 1 h after one lung ventilation (T2),the end of surgery (T3) and 24 h after operation (T4).Blood gas analysis was done at T1,T2,and T3.Plasma superoxide dismutase (SOD) activity and concentration of malonyldialdehyde (MDA),matrix metallo-proteinase-9 (MMP-9),interleukin-6(IL-6) and white blood cell (WBC) and neutrophil granulocyte (PMN) counts were measured at T0,T2,T3 and T4.The complications including pulmonary infection and atelectasis were recorded at 1,3 and 7 days after operation.Results At T2-3,PaO2 was higher in groups of OR and ORD than in group C Group ORD had higher PaO2 than did group OR [(265±15) mmHg,(305±23) mmHg vs.(231±17) mmHg,(273±21)mmHg,(312±24) mmHg vs.(242±18) mmHg,F=34.791 and 31.813,P＜0.01].At T2-3,RI was lower in groups of OR and ORD than in group C,and group ORD had lower RI than did group OR [(1.48±0.16),(1.14 ±0.14) vs.(1.86±0.18);(1.35±0.13),(0.96±0.09) vs.(1.73±0.15),F=119.260 and 164.855,P＜0.01].At T3-4,SOD activity was higher in group OR and ORD than in group C,and group ORD had higher SOD activity than did group OR [(83.6 ± 7.8) U/mg prot,(97.6± 9.5) U/mgprot vs.(70.5±7.4) U/mgprot;(73.5 ± 6.3) U/mgprot,(87.7 ± 8.9) U/mgprot vs.(61.6 ± 5.4) U/ mgprot,F=94.540 and 90.839,P＜0.01].At T3-4.plasma concentration of MDA,MMP-9,WBC and PMN counts were lower in group OR and ORD than in group C,and the above indices were lower in group ORD than in group OR [(7.5 ± 1.4) nmol/mgprot,(5.8 ± 1.0) nmol/mgprot vs.(9.5 ±1.5) nmol/mgprot;(8.2± 1.5) nmol/mgprot,(6.5 ± 1.0) nmol/mgprot vs.(10.1 ±1.6) nmol/mgprot;(205±23) μg/L,(173±21) μg/L vs.(237±26) μg/L,(179±16) μg/L,(158±12) μg/L vs.(203± 20) μg/L;(8.0±0.5) ×109/L,(7.2±0.6) × 109/L vs.(9.2±0.8)×109/L;(9.4±0.7) ×109/L,(8.2±0.6)×109/Lvs.(11.2±0.8) ×109/L;(7.4±0.7) ×109/L,(6.5±0.5) ×109/Lvs.(8.3 ±0.8) ×109/L,(7.8±0.8) ×109/L,(6.7±0.6) ×109/L vs.(9.2±0.9) ×109/L,F=98.872,52.723;198.307,47.622,20.319,36.935,18.197,35.036,respectively,all P＜0.01].At T2-4,IL-6 level was lower in groups of OR and ORD than in group C,and group ORD had lower IL-6 level than did group OR [(105±14) ng/L,(86±12) ng/L vs.(127±18) ng/L;(125±19) ng/L,(101±16) ng/ L vs.(156±22) ng/L;(110±16) ng/L,(89±12) ng/L vs.(132±20) ng/L,F=85.449,139.848,124.129,respectively,P＜0.01].The incidences of postoperative pulmonary infection and atelectasis were lower in group OR and ORD than group C,and group ORD had lower incidences of postoperative pulmonary infection and atelectasis than did group OR (x2 =6.303 and 14.545,P ＜ 0.05).Conclusions RIPC combined with dexmedetomidine can improve pulmonary function in elderly patients with thoracotomy and pulmonary dysfunction,may relieve the inflammatory reaction and oxidation reaction during perioperative period and finally help to improve the prognosis of patients.