Intracuff Lidocaine Carbonate Suppress Extubation Complications

Objective: To investigate the effectiveness and safety of filling endotrachealtube(ETT) cuff with1.73%lidocaine carbonate on reducing extubationcomplications.Methods: In vitro study: Eighteen7.5mm ID ETT were divided into three groups,each group contained six. Group L was filled with2%lidocaine chloride10ml,Group CL1was filled with0.865%lidocaine carbonate10ml and Group CL2wasfilled with1.73%lidocaine carbonate10ml. All ETT were placed in20ml waterfor24h hot bath at38℃. Samples were drawn from bath water at15min,30min,45min,60min,90min,120min,150min,180min,210min,240min,300min,360min. Lidocaine concentration was detected by HPLC analysis. In vivo study:Sixty-four patients underwent general anesthesia for elective lower abdominalsurgeries were randomly assigned into four groups, each group contained sixteen.ETT cuffs were filled with air in Group A, saline in Group S,2%lidocainechloride in Group L and1.73%lidocaine carbonate in Group CL, respectively.Observe extubation cough reflex and hemodynamic changes, and sore throat,hoarseness, dysphonia, nausea and vomiting in15min(T0),1h(T1),2h(T2),3h(T3)and24h(T4) postoperative.Results: In vitro study:(1) Each group demonstrated an increase in bothconcentration and dosage of lidocaine. The highest lidocaine concentration was reached in Group CL2with820.15±84μg/ml while416.71±28μg/ml in GroupCL1and3.71±0.6μg/ml in Group L.(2) Lidocaine infiltration rate in GroupCL1and Group CL2reached peak at240min (1954.17±951μg/h) and120min(4433.97±286μg/h) respectively, then decreased.(3) By360min lidocaineinfiltration dose was16402.90±1678μg in Group CL2,8334.23±567μg inGroup CL1and4.27±12μg in Group L.(4) There was no solution precipitationduring the whole testing time and all cuffs remained intact. In vivo study:(1)Compared with Group A and Group S postoperative sore throat were less severe inGroup CL and Group L(P<0.05). In T0, T1, T2, sore throat was less severe inGroup CL than Group L(P<0.05).(2) There was a significant increase of ETTtolerance time in Group CL.(3) Cough, nausea, vomiting, dysphonia andhoarseness were more likely to happen in Group A and Group S.(4) Extubationhemodynamics were more stable in Group CL.Conclusion: Filling ETT cuff with1.73%lidocaine carbonate can reduceETT-induced emergence phenomena after general anesthesia and extubationcomplications with efficacy and safety.