Optimal Size Of Laryngeal Mask Airway In Breast Surgery And Risk Factor Of Post Operative Soar Throat

ObjectiveLaryngeal mask airway has been widely used in the ambulatory outpatient surgery.The choice of laryngeal mask size according to the weight of the patient is currently the most commonly used method in clinical practice.However,this method of choice of the mask for the neck anatomical abnormalities may not be applicable and the error rate may increase.Although the laryngeal mask is easy to operate and there is less irritation,the complications caused due to laryngeal mask should also be taken seriously.In this study,we examined whether the four anatomical landmarks of the pharynx could be used for selecting the optimal size of the laryngeal mask for patient undergoing breast surgery under general anesthesia and compare the correlation and risk factors of the postoperative pharyngeal complication between the tracheal intubation and laryngeal mask airway.Materials and Methods1.ligibility criteria was female patients undergoing general anesthesia for breast surgery,cases 70 comprehensive evaluation of size of cLMA done according to four pharyngeal parameters(including mouth opening,tongue width,thyroid cartilage width,thyromental distance).After the induction of general anesthesia,the mask was manually ventilated,and after the patient's consciousness and eyelash reflex disappeared,the laryngeal mask was inserted.Then whether there was any leaks after insertion was checked,if there was leakage mask position was adjusted,if the adjustment failed three times,the cLMA was replaced.Record the four pharyngeal anatomical parameters,analyze standard for laryngeal mask airway selection.2.ligibility criteria was female patients undergoing general anesthesia for breast surgery,118 cases,patients randomly divided into laryngeal mask group and endotracheal intubation group.The laryngealmask group omprehensive evaluation of size of cLMA done according to four pharyngeal parameters(including mouth opening,tongue width,thyroid cartilage width,thyromental distance)and the tracheal intubation group,size 6.5 threaded ET tube.After induction of general anesthesia,mask manual ventilation done,after patient consciousness and eyelash reflex disappeared,mandibular relaxation,then laryngeal mask or threaded tracheal tube was inserted.In the laryngeal mask group.Results1.There was statistical difference between the size 3 laryngeal mask group and the size 4 laryngeal mask group in hight,weight and BMI.In case of the tongue width and the thyromental distance there is statically significant difference(P <0.05).2.The general features of the two groups of patients,the four anatomical parameters,the intra-operative EtCO2,oxygen saturation(SpO2),tidal volume,respiratory rate there is no significant difference(P> 0.0.5),the peak airway pressure of laryngeal mask airway group was lower than that of endotracheal tube group(P <0.05).In the PACU,postoperative 24 hrs sore throat incidence was higher(33%)in laryngeal mask group than that tracheal tube group(29%),and there was no significant difference between two groups(P>0.0.5).The width of the tongue and height could be the risk factor for postoperative sore throat in laryngeal mask airway.In endotracheal tube,age be the risk factor for postoperative sore throat.ConclusionsThe width of tongue and thyroid cartilage may be a criterion for selecting the size of the laryngeal mask.The width of mouth opening and thyromental distance may not be a criterion for selecting the size of the laryngeal mask.The compression injury induced sore throat due to laryngeal mask is not less than that of the tracheal tube.Postoperative sore throat may associated with tongue width.In endotracheal tube,Postoperative sore throat may associated with age.