Résumé
Objective To evaluate the effects of different doses of dexmedetomidine on lung injury in pediatric patients undergoing open heart surgery under cardiopulmonary bypass (CPB).Methods Forty-eight pediatric patients,aged 7 months-3 yr,of ASA physical status Ⅱ or Ⅲ,scheduled for elective repair of ventricular septal defect under CPB,were randomly divided into 4 groups (n =12 each) using a random number table:control group (group C) and 3 different doses of dexmedetomidine groups (D1-3 groups).Anesthesia was induced with midazolam,fentanyl and vecuronium.The patients were endotracheally intubated and mechanically ventilated.In D1-3 groups,dexmedetomidine 0.5μg/kg (initial dose) was given over more than 10 min,followed by continuous infusion at 0.1,0.3 and 0.5 μg· kg-1 · h-1,respectively,until the end of operation.The equal volume of normal saline was given instead of dexmedetomidine in group C.Before administration (T1),and at 2,6 and 12 h after termination of CPB (T2-4),blood samples were collected for determination of plasma tumor necrosis factor-α (TNF-α),interleukin-6 (IL-6) and IL-8 concentrations and for blood gas analysis.Respiratory index (RI),oxygenation index (OI) and lung compliance (CL) were calculated.Results The plasma concentrations of TNF-α and IL-8 at T2-4 and IL-6 at T3,4 were significantly lower in D2,3 groups than in group C.Compared with group D1,the plasma concentrations of TNF-α,IL-8 and RI were significantly decreased,and OI and CL were increased at T2-4 in D2-3 groups,and the plasma IL-6 concentrations at T3,4 in group D2 and at T2-4 in group D3 were decreased.The plasma concentrations of TNF-α and IL-6 were significantly lower,while OI and CL were higher at T2,3,and the plasma concentrations of IL-8 and RI were lower at T2-4 in group D3 than in group D2.Conclusion Dexmedetomidine can reduce lung injury in pediatric patients undergoing open heart surgery under CPB and promote the lung function after CPB possibly through inhibiting inflammatory responses to CPB dosedependently.
Résumé
ObjectiveTo investigate the effect of reduced ghtathione (GSH) pretreatment on inflammatory factors and oxygen free radical in patients during one-lung ventilation (OLV).MethodsThirty patients with lung cancer undergoing lung resection were divided into GSH group(15 cases) and control group ( 15 cases) by random digits table.In GSH group,GSH 30 mg/kg in normal saline 100 ml was infused after induction of anesthesia before OLV,while in control group equal volume of normal saline was infused instead of GSH.Blood samples were collected before induction of anesthesia (T0) and at 30 min(T1),60 min (T2) of OLV and 60 min of two-lung ventilation (T3) and at 2 h after operation(T4) for determination of serum tumor necrosis factor(TNF)-α,interleukin(IL)-8 and malonaldehyde(MDA) concentrations and superoxide dismutase(SOD) activity.ResultsThe serum MDA concentrations at T2-T4 were higher than those at T0 in two groups (P＜ 0.05) [GSH group:(3.5 ± 0.6),(3.8 ± 0.8),(4.7 ± 1.1 ),(6.1 ± 1.2),(6.4 ± 0.9) mol/L at T0-T4;control group:(3.7 ±0.5),(4.1 ±0.6),(5.9 ± 1.2),(7.4 ± 1.0),(7.8 ± 1.1) mol/L at T0-T4],but GSH group was lower than control group(P＜ 0.05 ).The serum SOD activity at T2-T4 was lower than that at T0 in control group (P＜ 0.05),and lower than GSH group(P＜ 0.05).The serum TNF-α,IL-8 concentrations at T1-T4 were higher those that at T0 in two groups(P ＜ 0.05 ),the serum TNF- α concentrations at T2-T4 and IL-8 concentrations at T1-T4 in GSH group were lower than those in control group (P ＜0.05).Conclusion Pretreatment with GSH 30 mg/kg can decrease inflammatory response and lipid peroxidation during OLV.
Résumé
ObjectiveTo investigate the effects of cardioplegic solution enriched with different doses of glutathione on myocardial injury in children undergoing cardiac surgery under cardiopulmonary bypass (CPB).MethodsForty-eight ASA [Ⅱ or Ⅲ patients aged 2-5 yr undergoing repair of ventricular septal defect under CPB were randomly divided into 4 groups (n ＝ 12 each):control group (group C) and cardioplegic solution containing 3 different-dose of glutathione groups ( group G1-3 ).Glutathione 50,75,100 mg/kg were added to cardioplegic solution in group G1-3 respectively.Blood samples were collected before operation (T0),at 30 min after release of aortic cross-clamp (T1),at 6,12,24 h after termination of CPB (T2-4) for determination of plasma cTnI concentration.Myocardial specimens were obtained from right auricle before aortic cross-clamp and 15 min after release of aortic cross-clamp.The ultrastructure of myocardium was examined with scanning electron microscope.A mitochondrial FlaMeng semiquantitative analysis was done.ResultsThe plasma concentration of cTnI at T3,4 were significantly lower in groups G1,2 than in group C.The plasma concentration of cTnI at T1-4 were significantly lower in group G3 than in group C and group G1,2.The quantization score of myocardial mitochondria at 15 min after release of aortic cross-clamp were significantly lower in group G3 than in group C and group G1,2.Micorscopic examination showed that the injury to myocardial ultrastructure was attenuated in group G3 compared with group C.Conclusion Cardioplegic solution enriched with glutathione can reduce myocardial injury induced by CPB in a dose dependent manner.Glutathione 100 mg/kg can exert a visibly protective effect on myocardium.