Pulmonary protective effect of penehyclidine hydrochloride during heart valve replacement under cardiopulmonary bypass

Objective To investigate the protective effect of penehyclidine hydrochloride (PH) on lungs against acute lung injury induced by cardiopulmonary bypass (CPB) and its protection mechanism.Methods Sixty patients undergoing valve replacement under CPB were randomly divided into three groups(20 patients for each group):PH group 1 (P1),PH group 2(P2) and control group(C) were received 0.05 mg/kg,0.1 mg/kg of PH(diluted to 10 ml with saline) and equal volume saline,respectively at beginning of operation via central vein.And artery blood was drawn at before intravenous injection of PH(T1),30 min after aortic clamping(T2),30 min after aortic unclamping(T3),4 h and 24 h after aortic unclamping(T4 and T5) to do artery blood gas analysis.Recordings of PaCO2,PaO2,and FiO2 were measured at each measuring point to calculate respiratory index(RI) and oxygenation index(OI).VT,Pmax and PEEP were recorded at after intubation 10 min,30 min,the beginning of CPB,after CPB 30 min and 60 min to calculate pulmonary dynamic compliance (Cd).Results There was no significant difference in RI and OI among three groups at T1 (P ＞ 0.05).RI in group P1 and group P2 were much lower than those in group C at T2-T5 (P ＜ 0.01),OI in group P1 and group P2 were much higher than those in group C at T2-T5 (P ＜0.01),but RI and OI of group P1 and group P2 had no significantly different(P ＞0.05).There was no significant difference in Cd among three groups at after intubation 10 min(P ＞0.05).Cd in group P1 and group P2 were much higher than those in group C at after intubation 30 min,before and after CPB(P ＜0.01),but Cd of group P1 and group P2 had no significantly different(P ＞ 0.05).Conclusions Penehyclidine hydrochloride,significantly lowering RI and heightening OI and Cd,can improve pulmonary function and reduce acute lung injury. Key words: Penehyclidine hydrochloride;  Cardiopulmonary bypass;  Acute lung injury;  Respiratory index;  Oxygenation index ;  Pulmonary dynamic compliance