Role of laryngeal mask airway in laparoscopic cholecystectomy

Laparoscopic cholecystectomy is one of the most commonly performed surgical procedures and the laryngeal mask airway(LMA) is the most common supraglottic airway device used by the anesthesiologists to manage airway during general anesthesia. Use of LMA has some advantages when compared to endotracheal intubation, such as quick and ease of placement, a lesser requirement for neuromuscular blockade and a lower incidence of postoperative morbididy. However, the use of the LMA in laparoscopy is controversial, based on a concern about increased risk of regurgitation and pulmonary aspiration. The ability of these devices to provide optimal ventilation during laparoscopic procedures has been also questioned. The most important parameter to secure an adequate ventilation and oxygenation for the LMA under pneumoperitoneum condition is its seal pressure of airway. A good sealing pressure, not only state correct patient ventilation, but it reduces the potential risk of aspiration due to the better seal of airway. In addition, the LMAs incorporating a gastric access, permitting a safe anesthesia based on these commented points. We did a literature search to clarify if the use of LMA in preference to intubation provides inadequate ventilation or increase the risk of aspiration in patients undergoing laparoscopic cholecystectomy. We found evidence stating that LMA with drain channel achieves adequate ventilation for these procedures. Limited evidence was found to consider these devices completely safe against aspiration. However, we observed that the incidence of regurgitation and aspiration associated with the use of the LMA in laparoscopic surgery is very low.

Total intravenous general anesthesia with laryngeal mask airway for transurethral resection of bladder tumor

Objective： To observe the advantage of total intravenous anesthesia for transurethral resection of bladder tumor （TURBT）. Methods.. Sixty ASA Ⅰ-Ⅱ patients undergoing TURBT were randomly assigned to 2 groups. Spinal anesthesia with 0. 75% pure bupivacaine （8-12 rag） was applied to patients in Group Ⅰ （n= 30）. Patients in Group Ⅱ （n=30） received total intravenous anesthesia with continuous infusion of Propofol and Remifentanil ; and a laryngeal mask was used to ensure the airway and ventilation. BP, HR, SPO2 and pertinent side effects were monitored and recorded. Results ： The patients in group Ⅱ experienced more stable hemodynamics than those in group Ⅰ . Obturator nerve reflex was observed in 15 （50. 0%） patients in Group Ⅰ , but none （0%） in Group Ⅱ （P〈0. 01）. Conclusion.. Total intravenous anesthesia with laryngeal mask is a safe, reliable, controllable and simple manual for patient undergoing TURBT.

General Anesthesia with Laryngeal Mask Airway: Etomidate VS Propofol for Hemodynamic Stability

Background: Propofol is the most popular induction agent for laryngeal mask airway (LMA) insertion in current anaesthesia practice however associated hypotension has been reported as its major disadvantage. Etomidate, which produces less hypotension, can be considered as an alternative agent for LMA insertion. Objectives: The objective of this study was to compare the hemodynamic effects of etomidate with propofol for induction of general anaesthesia (GA) for LMA. Ease of inserting LMA was also looked at. Material and Methods: It was a prospective randomized double blinded study. All ASA I and II patients of 15 - 60 years of age undergoing general anaesthesia with LMA for elective surgeries were included. Patients were induced with intravenous (I/V) fentanyl and induction agent either etomidate or propofol according to group randomization. LMA was inserted after 30 seconds. Intra-operative heart rate (HR), sys tolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), number of attempts and duration of LMA insertion were monitored. Results: There was no difference in the heart rate between the two groups. A significant drop was found for systolic blood pressure (SBP) in propofol group while diastolic blood pressure (DBP) was decreased in both the groups. In propofol group, successful insertion of LMA was achieved on the first attempt in 93.3% of patient as compared to 36.7% in etomidate group. Conclusion: Use of etomidate for induction of laryngeal mask anesthesia can prevent the hypotension following induction;however it may delay the insertion of laryngeal mask airway.

Nursing Care of the Laryngeal Mask Airway in Pediatric Cataract Surgery

Purpose:.To investigate the important experience of nursing care of the laryngeal mask airway(LMA) in children undergoing cataract surgery.Methods: Fifty-five children undergoing cataract surgery were anesthetized by inhaling sevoflurane through a LMA and received perioperative nursing care. The safety of perioperative nursing for these children was also evaluated.Results: Through perioperative nursing care and psychological counseling for children with LMA,.all patients were anesthetized without complications and underwent successful surgeries..No severe postoperative complications were observed.Conclusion: Nursing care specific for LMA is a vital part of the success of anesthesia and pediatric cataract surgery.

Lingual nerve injury caused by laryngeal mask airway during percutaneous nephrolithotomy:A case report

BACKGROUND Lingual nerve injury(LNI)is a rare complication following the use of laryngeal mask airway(LMA).The occurrence of this unexpected complication causes uncomfortable symptoms in patients and worsens their quality of life.We present an unusual case of LNI caused by the use of an LMA in percutaneous nephrolithotomy(PCNL).CASE SUMMARY A 49-year-old man presented to our hospital with a 3-year history of intermittent left lower back pain.Abdominal computed tomography showed a 25 mm×20 mm stone in the left renal pelvis.PCNL surgery using LMA was performed to remove the renal stone.The patient reported numbness on the tip of his tongue after the operation,but there were no signs of swelling or trauma.The patient was diagnosed with LNI after other possible causes were ruled out.The symptom of numbness eventually improved after conservative medical therapy for 1 wk.The patient completely recovered 3 wk after surgery.CONCLUSION This is the first case report describing LNI with the use of LMA in PCNL.In our case,an inappropriate LMA size,intraoperative movement,and a specific surgical position might be potential causes of this rare complication.

Use of Laryngeal Mask Airway in the Management of a Difficult Airway: A Case Report

Background: Difficulty in management of the airway occurs most frequently in patients who have Mallampati grade III and IV, and other unfavourable airway findings like short neck, restriction in range of motion of the temporoman-dibular joints and inadequate neck flexion and extension. Because of unavailability of fibreoptic bronchoscopes or inexperience in their use, laryngeal mask airway (LMA) has become a common and acceptable airway management option. This is a case report of a postmenopausal woman who had her airway managed with LMA following initial failed intubation necessitating a rescheduling of the operation. Result: The patient had a successful surgery and postoperative recovery was uneventful. Conclusion: The LMA is a useful option in the management of an anticipated or unexpected difficult airway, especially in resource-poor settings where fibreoptic bronchoscopes may not be readily available.

Severe gastric insufflation and consequent atelectasis caused by gas leakage using AIR-Q laryngeal mask airway:A case report

BACKGROUND The airways of patients undergoing awake craniotomy(AC)are considered“predicted difficult airways”,inclined to be managed with supraglottic airway devices(SADs)to lower the risk of coughing or gagging.However,the special requirements of AC in the head and neck position may deteriorate SADs’seal performance,which increases the risks of ventilation failure,severe gastric insufflation,regurgitation,and aspiration.CASE SUMMARY A 41-year-old man scheduled for AC with the asleep–awake–asleep approach was anesthetized and ventilated with a size 3.5 AIR-Q intubating laryngeal mask airway(LMA).Air leak was noticed with adequate ventilation after head rotation for allowing scalp blockage.Twenty-five minutes later,the LMA was replaced by an endotracheal tube because of a change in the surgical plan.After surgery,the patient consistently showed low tidal volume and was diagnosed with gastric insufflation and atelectasis using computed tomography.CONCLUSION This case highlights head rotation may cause gas leakage,severe gastric insufflation,and consequent atelectasis during ventilation with an AIR-Q intubating laryngeal airway.

The effect of different inflation volumes of laryngeal mask airway on efficacy of closed circuit controlled ventilation in pediatric cancer patients

Objective： The laryngeal mask airway （LMA） is an established way for airway control during spontaneous ventila- tion. Its ability to deliver positive pressure ventilation without leakage especially in low flow states is still controversy. The aim of this study is to test the possibility of using LMA in pediatric closed circuit controlled ventilation, and to find out the optimum cuff volume to perform closed system ventilation. Methods： Twenty children scheduled for elective surgeries were enrolled in a crossover study. Laryngeal mask airway was used. In stage I, the cuff was inflated with the maximum volume of air as rec- ommended by the manufacturers. Adjustment of volume of air inflated into the LMA cuff to the minimum volume to obtain the effective seal was done at stage II. The leak pressure, intracuff pressure and the leak volume were measured in both stages. Results： The cuff filling volume was significantly lower compared to the maximum cuff inflation volume in stage I. Leakage values showed significantly less values in stage II of the study with smaller cuff inflation volumes. The airway leakage pressure was significantly lower in stage fl in comparison to stage I. Cuff inflation pressure in stage I showed marked elevation which dropped significantly after adjustment of cuff volume in stage I1. Conclusion： Laryngeal mask airway is an effective tool to provide closed circuit controlled ventilation in pediatrics. Inflation of the cuff by the minimum volume of air needed to reach the just sealing pressure is suggested to minimize the leakage volume.

Effect of different types of laryngeal mask airway placement on the right internal jugular vein: A prospective randomized controlled trial

BACKGROUND In recent years, with the popularity of laryngeal mask airway(LMA) for the management of clinical anesthesia, the influence of the LMA on the position and blood flow of the internal jugular vein(IJV) has attracted an increasing amount of attention.AIM To investigate the effect of placement of different types of LMA(Supreme LMA,Guardian LMA, I-gel LMA) on the position and blood flow of the right IJV.METHODS This was a prospective randomized controlled trial. A total of 102 patients aged 18-75 years who were scheduled to undergo laparoscopic abdominal surgery with general anesthesia were randomly assigned to three groups: Supreme LMA(group 1), Guardian LMA(group 2), and I-gel LMA(group 3) groups. The main indicator was the overlap index(OI) of IJV and the common carotid artery(CCA)at the high, middle, and low points before and after the placement of the LMA.The second indicators were the proportion of ultrasound-simulated needle crossing the IJV and CCA, and the cross-sectional area and blood flow velocity of the IJV before and after placement of the LMA at the middle point.RESULTS Data from 100 patients were included in the statistical analysis. The OI increased significantly after placement of the LMA in the three groups at the three points(P< 0.01), except group 2 at the low point. In group 2 and group 3, the OI was lower than that in group 1 after LMA insertion at the high point(P < 0.0167). At the middle point, after LMA insertion, the proportion of simulated needle crossing the IJV significantly decreased in all three groups(P < 0.05), and the proportion in group 2 was higher than that in group 3(P < 0.0167). The proportion of simulated needle crossing the CCA or both the IJV and CCA significantly increased in group 1 and group 2(P < 0.05), which increased with no statistical significance in group 3. After LMA insertion, the cross-sectional area of the IJV significantly increased, while the blood flow velocity significantly decreased(P <0.01). There was no significant difference among the three groups.CONCLUSION The placement of Supreme, Guardian, and I-gel LMA can increase the OI, reduce the success rate of IJV puncture, increase the incidence of arterial puncture, and cause congestion of IJV. Type of LMA did not influence the difficulty of IJV puncture. Therefore when LMA is used, ultrasound is recommended to guide the IJV puncture.

Assessment of Laryngeal Mask Airway in General Anesthesia during Thyroidectomy without Applying Miorelaxants

The selective approach of anesthesia has a crucial role in the surgical treatment of thyroid diseases.Anesthesia during the insertion of a laryngeal mask airway is an alternative instead of endotracheal tube,hence this is a novel period in anesthesiology.

Shikani Optical Stylet–guided Intubation via the Intubating Laryngeal Airway in Patients With Scar Contracture of the Face and Neck

Objective To evaluate the feasibility of the Shikani Optical Stylet （SOS）-guided inmbation through a new Intubafing Laryngeal Airway （ILA） in anticipated difficult airways caused by scar contracture of the face and neck. Methods Thirty-three adult patients with anticipated difficult airways undergoing selective faciocervical scar plastic surgery under general anesthesia were enrolled in this study. After anesthesia induction, a size 2.5, 3.5 or 4.5 ILA was inserted. Following good lung ventilation being verified, the SOS preloaded with an endotracheal tube was inserted via the ILA. Once the clear vocal cords came into view under the SOS, the endotracheal tube was advanced through glottis into the trachea. Results The ILA provided an effective airway in all patients, lntubation was successful at the first attempt on 22/33 （66.7%） occasions and at the second attempt on 6/33 （18.2%）. Intubation failed in 5 （15.1%） patients who suffered from severe limitation of head extension due to scar contracture of the neck. These patients＇ tracheas were finally intubated using a fibreoptic bronchoscope via the ILA. Conclusions The SOS-guided intubating method via the ILA is a feasible technique in patients with scar contracture of the face and neck. However, in patients with severe limitation of head extension, the use of SOS cannot be recommended. The SOS can be used as an alternative apparatus when the fibreoptic bronchoscope is not available.

Comparative study of hemodynamic responses to orotra- cheal intubation with intubating laryngeal mask airway and direct laryngoscope

Background Intubating laryngeal mask airway （ILMA） offers a new approach for orotracheal intubation and is expected to produce less cardiovascular stress responses. However, the available studies provide inconsistent results. The purpose of this study was to identify whether there is a clinically relevant difference in hemodynamic responses to orotracheal intubation by using ILMA and direct laryngoscope （DLS）. Methods A total of 53 adult patients, ASA physical status I-II, scheduled for elective plastic surgery under general anesthesia requiring the orotracheal intubation, were randomly allocated to either DLS or ILMA groups. After a standard intravenous anesthesia induction, orotracheal intubation was performed. Noninvasive blood pressure and heart rate were recorded before （baseline values） and after anesthesia induction （post-induction values）, at intubation and every minute for the first 5 minutes after intubation. The data were analyzed using Chisquare test, paired and unpaired Student＇s t test, and repeated-measures analysis of variance as appropriate. Results The mean intubation time in the ILMA group was longer than that in the DLS group （P〈0.05）. The blood pressure and heart rate increased significantly after intubation in the two groups compared to the postinduction values （P〈0.05）, but the maximum value of blood pressure during the observation did not exceed the baseline value, while the maximum value of heart rate was higher than the baseline （P〈0.05）. During the observation, there were no significant differences in blood pressure and heart rate among each time point and in the maximum values between the two groups. Conclusions Orotracheal intubations by using ILMA and DLS produce similar hemodynamic response. ILMA has no advantage in attenuating the hemodynamic responses to orotracheal intubation compared with DLS.

Application of Minimum Effective Cuff Inflating Volume for Laryngeal Mask Airway and its Impact on Postoperative Pharyngeal Complications

Background：High intracuffpressure can cause severe pharyngeal complications including sore throat or hoarseness after laryngeal mask airway （LMA） removal postoperatively.Though the application of minimum effective cuffinflating volume is suggested to maintain airway sealing and adequacy of ventilation for patients receiving general anesthesia with LMA at lower level of the intracuffpressure,it is currently not a standard care in most of the anesthetic departments.In this study,the minimum effective cuff inflating volume was determined for classic LMA Well LeadTM （Well Lead Medical Co.,Ltd.,China） and its impact on postoperative pharyngeal complications was also explored.Methods：Patients with American Society of Anesthesiologists physical status （Ⅰ-Ⅲ） undergoing the short-duration urological surgery were recruited in this trial.First,the minimum effective cuff inflating volume was determined for size 4 or 5 LMA Well LeadTM in the study 1.Immediately following placement and confirmation of ideal LMA position,the cuff was inflated with 5,7,10 ml of air and up to 30 ml at 5 ml increment.The intracuff pressure,oropharyngeal leak pressure （OLP）,and inspiratory peak airway pressure under positive pressure ventilation at the corresponding cuff volume as indicated above were recorded.Second,the enrolled patients were randomly allocated into minimum effective cuff inflating volume group （MC） and routine care （RC） group in the study 2.The minimum effective cuff inflating volume was applied and maintained in MC group,whereas the cuff volume was inflated with half of the maximum cuff inflating volume recommended by manufacturer in RC group throughout the surgical procedure and stay in postanesthesia care unit prior to LMA removal.The incidence of pharyngeal complications at 0,2,24,and 48 h after removal of LMA and other intra-operative adverse events were also documented.Results：The intracuffpressure varied with the cuff inflating volume in a positive linear correlation manner （Y =11.68X-42.l,r2 =0.9191） under the range of 5-30 ml for size 4 LMA.In similar with size 4 LMA,the data were also showed the linear relationship between the intracuff pressure and the cuff inflating volume （Y =7.39X-10.9,r2 =0.8855） for size 5 LMA.The minimal effective cuff inflating volume for size 4 or 5 LMA was 7-9 ml in combination of considering OLP needed to maintain airway sealing during intermittently positive pressure ventilation.The intracuffpressure in MC group was lower compared with RC group （63.0 ± 3.7 vs.126.4 ± 24.0 cmH2O for size 4 LMA;55.6 ± 2.4 vs.138.5± 26.8 cmH2O for size 5 LMA;P ＜ 0.0001）.The incidence of pharyngeal adverse events was lower in MC group versus the RC group at 2,24 h after LMA removal.Conclusions：The relationship between the cuff inflating volume and the intracuffpressure for size 4 or 5 LMA Well LeadTM is in a linear correlation manner at the range of 5-30 ml.The minimal cuffinflating volume is adequate for satisfactory airway sealing and consequently associated with lower incidence of postoperative pharyngeal complications for LMA Well Lead.TM

Safety of removal of ProSeal laryngeal mask airway in children in the supine versus lateral position in a deep plane of anesthesia:A randomized controlled trial

Importance:When a ProSeal laryngeal mask airway(PLMA)is removed with the child in a deep plane of anesthesia,the upper airway muscle tone and protective upper airway reflexes may be obtunded.Objective:To determine whether the supine or lateral position is safer for the removal of a PLMA in deeply anesthetized children by comparing the incidence of upper airway complications.Methods:This randomized single-blind comparative trial was conducted at a tertiary care hospital between January 2020 and September 2020.Forty children of the American Society of Anesthesiologists class I/II of ages 1–12 years age undergoing surgery under general anesthesia with PLMA used as the definitive airway device were recruited.Patients were randomly allocated to lateral group or supine group for PLMA removal in a deep plane of anesthesia in the lateral or supine position.The primary outcome was the number of patients experiencing one or more upper airway complications and the secondary outcomes were incidence of individual respiratory adverse effects and of severe airway complications.Results:The incidence of airway complications was 30%in the supine group and 20%in the lateral group(P=0.6641).Incidence of laryngospasm,immediate stridor,and excessive secretions were similar.Early stridor and oxygen desaturation were higher in the supine group(P=0.0374,P=0.0183 respectively).Interpretation:The overall incidence of upper airway complications was similar with the removal of a PLMA in the supine or lateral position in deeply anesthetized children.The incidence of oxygen desaturation and stridor were higher with PLMA removal in the supine as compared to the lateral position.

Successful Anaesthetic Management of Caesarean Section: An Experience on a Patient with Myasthenia Gravis and Difficult Airway

The anaesthetic management of the pregnant woman with myasthenia gravis (MG) is very challenging to the anaesthesiologist. This situation becomes exaggerated in emergency settings in a low resource area, especially when attending anesthesiologists for the first time took care of her. Here, we present a case that illustrates this situation. A G3 P2 pregnant woman presented for an emergency caesarean section (CS) due to premature rupture of the membranes. The patient had been misinformed by her neurophysician not to undergo general anaesthesia at CS. She had no motor weakness and no bulbar symtoms. The only abnormal finding was a stiff neck and a Mallampati #2 score, which predicted a difficult airway. Spinal anaesthesia was not successful after several attempts. General anaesthesia was considered but again intubation was not successful. We performed anesthesia with a second generation laryngeal mask airway with successful CS. Pregnant women with MG require personalised care from a multidisciplinary team. While regional anaesthesia is reported to be the better choice in CS for women with MG, regional anesthesia is not always possible. Anesthesia should be chosen in a patient-by-patient manner. The present case illustrates such conditions, of which description may be useful for anesthesiologists and obstetricians.

Fiberoptic Intubation through Adapter Removable Supraglottic Airways;Comparison of the Air-Q ILA^TM, LMA Classic Excel^TM, and LMA Unique^TM

Study Objective: We studied the overall efficacy of fiberoptic aided intubation using three different supraglottic airways (SGA) as intubation conduits with a standard endotracheal tube (ETT) to determine which, if any, is superior as an intubation conduit. Design: After induction of general anesthesia, subjects were randomized to one of three groups: Air-Q ILATM, LMA Classic ExcelTM, and LMA UniqueTM. Subjects were intubated with a fiberoptic aided technique with continuous ventilation with FiO2 = 1.0 through one of these SGAs. The primary endpoint was the overall efficacy of the intubation procedure. In addition, the following data were collected: demographic data, intubation times, grade of view of the larynx, and a visual analog scale (VAS) score of difficulty as determined by the primary anesthesiologist performing the procedure. Data were analyzed using a Kruskal-Wallis one-way analysis of variance and Post hoc analysis was done using Dunn’s Multiple Comparison Test. Results: 126 total subjects were studied. Intubation success rates were 100%, 87.8%, and 95% with the Air-Q ILATM, LMA Classic ExcelTM, and LMA UniqueTM respectively. There was no significant difference among the three different SGAs when comparing the times to place the SGA (T1), the true intubating time (T2), the time to remove the SGA (T3), or the total time (T4). Data were also stratified by the grade of view of the larynx;all grade I views, grade II views, and grade III views were grouped together regardless of the type of the SGA used. The grade I view of the larynx group had significantly faster true intubation times (T2 = 75.1 sec, p = 0.01) and significantly lower VAS scores (VAS = 1.9, P = TM provides the best view of the larynx and is the easiest one to use as an intubation conduit.

Investigating the Fluid Seal of Supraglottic Airway Devices in Humans Using Indicator Dye via the Drainage Tube:A Potential Roadmap for Future Studies

Background: The fluid seal of supraglottic airway devices (SGA) protects the airway from fluid contamination. We evaluated the suitability of indicator dye placement in the upper digestive tract of anesthetized patients combined with fiberoptical tracing to investigate the fluid seal of SGA. Methods: Patients swallowed a capsule of indigo carmine green (ICG) prior to induction of anaesthesia. After induction of anesthesia, one of two different SGA (either an i-GelTM or an LMA-SupremeTM (LMA-S)) was inserted after randomization. Methylene blue stained normal saline was injected through the proximal opening of drainage tube during mechanical ventilation as well as spontaneous breathing. We monitored regurgitation of ICG with a flexible fiberscope (FO) inserted through the drainage tube and checked for the appearance of methylene blue in the mask bowl with the FO inserted through the airway tube. Results: In thirty-six patients with an i-GelTM and 37 with a LMA-S no regurgitation of ICG was observed at the level of the upper oesophageal sphincter (UES). Methylene blue stained saline was not visible in any patient during pressure-controlled ventilation, but was detected in two of the 36 patients with the i-GelTM during spontaneous breathing. Conclusion: Instilling dye through the drainage tube of SGA models with a built-in drainage tube represents a useful method to examine and to compare the fluid seal of different SGA. Our protocol presented in this study proved to be an easy and reproducible approach for future studies. Furthermore, the clinical results gained during this evaluation highlight the necessity for further investigations regarding the fluid seal competencies of SGAs in humans under clinical conditions.

帝视观察用内窥镜辅助喉罩置入的临床效果

目的探讨帝视观察用内窥镜引导喉罩置入的效果,为临床麻醉气道管理提供依据。方法选择2022年3月至2024年3月在揭阳市人民医院行喉罩置入全身麻醉患者60例,采用随机数字表将纳入研究患者分为观察组和对照组,每组30例。观察组使用帝视观察用内窥镜辅助喉罩置入,对照组使用传统徒手喉罩置入法。记录两组患者喉罩置入成功总时间(喉罩进入口腔到判定喉罩置入成功)、喉罩首次置入成功率、气道峰压、口咽漏气压以及喉罩置入损伤并发症发生情况,包括麻醉恢复室拔除喉罩后喉罩表面有无血迹、术后24 h内咽痛发生率。结果与对照组比较,观察组喉罩置入成功总时间明显缩短(P<0.001),喉罩首次置入成功率明显升高(P<0.05),两组喉罩型号比较差异无统计学意义(P>0.05);与对照组比较,观察组气道峰压明显降低(P<0.001),口咽漏气压明显升高(P<0.001);两组喉罩表面有血迹、术后24 h内咽痛发生率比较差异无统计学意义(P>0.05)。结论帝视观察用内窥镜引导喉罩置入,可以提高喉罩首次置入成功率,缩短喉罩置入成功总时间,降低气道峰压,升高口咽漏气压,有较高安全性,值得推广。

减小喉罩型号改善通气效果的临床观察

目的探讨减小喉罩型号改善通气效果的临床观察。方法选取喉罩固定翼距门齿距离>3 cm的男性患者60例为研究对象,随机分为试验组和对照组,每组30例。比较试验组(3号喉罩)与对照组(4号喉罩)的通气优良率、FOB理想位置比例、气道峰压差及2组喉罩置入后的密封压、套囊内压、漏气率,比较2组喉罩远端与食道入口距离,观察2组喉罩拔出时带血丝情况,术后24 h咽部并发症发生情况(包括术后咽痛、声嘶)及咽痛持续时间。2组患者设置的呼吸参数相同。结果试验组喉罩置入后通气成功率、FOB理想位置置入比例及通气效果优良率提高,漏气率值降低,密封压值提高,喉罩远端距食道入口距离较对照组减小,术后咽部并发症发生率较对照组低,差异均有统计学意义(P<0.05)。结论对于喉罩固定翼距门齿距离>3 cm的患者,通过减小喉罩型号,使喉罩放置理想位置比例增加,通气优良率升高,漏气率降低,密封压值提高,咽部并发症降低,可改善喉罩通气效果,安全有效。