Laryngeal mask airway

The laryngeal mask airway (LMA) was first used in anaesthetic practice in the 1980s. It is now increasingly promoted as a first-line airway device during resuscitation, if a practitioner skilled in tracheal intubation is not available (Resuscitation Council (UK), 2002).     

Laryngeal mask airway bougie ultrasonography guided intubation in a morbidly obese patient with difficult airway

<正>Airway management of morbidly obese patients is challenging due to inherent anatomical and physiological variations.^[1] The frequent association of compromised hemodynamics, hypoxemia, or acidosis in an emergency department (ED) setting adds to the difficulty of the procedure. Rapid airway management position (RAMP),     

气管内插管和置喉罩应激反应的比较

目的 比较在麻醉诱导后气管内插管和置喉罩对病人的心血管反应和肾素—血管紧张素浓度的变化。方法 选择无心血管疾病 ,ASAI～II级 ,择期全麻手术患者40例 ,按投币法随机分成两组—气管内插管组(T组)和置喉罩组(L组) ,每组20例。气管内插管用喉镜明视插入法 ,喉罩按顺行盲探置入口底。全部病人均于诱导前 (t0)、气管内插管或置喉罩后即刻(t1)、1min(t2)、3min(t3)、5min(t4)测SBP、SDP、HR以及经颈内静脉采血标本2ML。血标本用放射免疫法测血管紧张素II(ATII)浓度、血管紧张素I(ATI)浓度时间变化率。结果 麻醉诱导后SBP、SDP、HR均下降(p<0.05) ,插管或置喉罩后即刻与1min两组比较有显著性意义 ,T组高于L组(p<0.05)。插管或置喉罩后ATII、ATI变化两组比较差别有显著性意义(p<0.05) ,且T组高于L组。结论 置喉罩对病人的应激反应小     

喉罩在非常规手术麻醉应用的新进展

喉罩作为一种声门上气道工具,由于无法完全保障气道的安全,临床应用受到某些患者特殊情况、手术类型和体位的限制。气管导管一直作为这类特殊患者或者手术术中维持气道的首选方法,近年来,随着喉罩设计的改进与技术的成熟,越来越多的麻醉医生选择喉罩代替气管导管用于非常规手术,有证据显示,只要谨慎选择患者和做好术中管理同样可以保障气道安全,并且更有利于维持循环稳定和减少气道并发症。本文通过讨论喉罩在剖宫产、俯卧位、妇科腹腔镜和胸腔镜手术中应用的优缺点,为临床应用提供参考意见。     

Laryngeal mask airway control versus endotracheal intubation by medical personnel wearing protective gear

The purpose of this study was to evaluate the rates of successful airway control using endotracheal tubes (ETs) or laryngeal mask airways (LMAs) and compare them between anesthetists and non-anesthetists wearing full antichemical protective gear. Anesthetists and non-anesthetists (n = 10 per group) twice attempted inserting ETs and LMAs on a mannequin model of airway management in a crossover, prospective manner. Times to successful insertion and failure rates were recorded. Non-anesthetists had a slightly higher failure rate inserting ETs compared with anesthetists (P = not significant). Respective mean times to successfully inserting ETs were 38 +/- 7.1 and 26.4 +/- 7.5 seconds (P < .05). Both groups inserted LMAs more rapidly than ETs (P < .05) and their failure rates in ET use were higher. In view of the relative rapidity by which LMAs were inserted as compared with ETs, by fully protected caregivers, the incorporation of LMA in algorithms dealing with emergency airway management in a nonconventional mass casualty scenario deserves further evaluation.     

Laryngeal mask airway in neonatal resuscitation: a survey of current practice and perceived role by anaesthesiologists and paediatricians

Objectives: To survey current practice and to compare the opinion of paediatricians and anaesthesiologists regarding laryngeal mask airway (LMA) in neonatal resuscitation. Design: A structured postal questionnaire on the use of the laryngeal mask airway in neonatal resuscitation was sent to the heads of department of the paediatric and anaesthesiology services. Setting: Forty-three hospitals in the Veneto Region, Italy. Results: During the year 2000, 1526 out of 33708 (4.5%) neonates in our region needed resuscitation. Of these cases, 101 (6.6%) were ventilated using the LMA. Laryngeal mask airway availability was significantly greater in the anaesthesiology department compared to the paediatric department (90% versus 50%; P=0.002). However, 52% of anaesthesiologists and 72% of paediatricians had never used the laryngeal mask airway in their practice. The laryngeal mask airway was considered as an essential device more frequently by the anaesthesiologists than by the paediatricians (27% versus 5%; P=0.015); both groups considered the laryngeal mask airway particularly useful in specific situations. Interestingly, while 16% of the paediatricians described the laryngeal mask airway as having no value, none of the anaesthesiologists did (P=0.002). Staff competence was considered low by 70% of anaesthesiology heads of department compared with 90% of their pediatric colleagues. In both specialties, use of the laryngeal mask airway was limited to medical staff. With regard to training, 35% of anaesthesiologists and 22.5% of paediatricians had attended a course on laryngeal mask airway use. Conclusions: Laryngeal mask airway availability and perceived value were higher amongst anaesthesiologists than their paediatric colleagues. However, educational level, competence and utilization rates of the LMA in neonatal resuscitation were low in both groups.     

食管引流型与标准型喉罩通气道用于正压通气的自身对照研究

目的采用随机自身对照设计方法比较食管引流型喉罩通气道(PLMA)和标准型喉罩通气道(SLMA)用于间歇正压通气的有效性。方法选择50例经美国麻醉医师协会(ASA)身体状态分级标准分为1~2级、拟在全身麻醉下实施择期整形外科手术患者。在常规麻醉诱导后,顺序插入PLMA和SLMA,将通气罩内压充气至60cmH2O(1cm H2O=0.098kPa),评价两种喉罩通气道充气前后的肺通气满意度和气道密封压,同时进行光导纤维支气管镜(FOB)评分,确定通气罩的解剖位置。然后将潮气量设定为10ml/kg实施间歇正压通气,记录间歇正压通气后连续5次呼吸的平均呼潮气量和平均吸气峰压。结果在通气罩未充气情况下,插入PLMA后有46例(92%)患者获得了良好和尚可的肺通气效果,而插入SLMA后仅有22例(44%)患者获得了良好和尚可的肺通气效果;PLMA的气道密封压显著高于SLMA(P<0.05)。将通气罩内压充气至60cmH2O,采用PLMA的50例患者均获得良好的肺通气效果,但采用SLMA时仅有28例获得良好的肺通气效果;PLMA所需的充气量和充气后获得的气道密封压均显著高于SLMA(P均<0.05)。采用PLMA时所有患者的气道密封压均高于或等于采用SLMA时;采用PLMA时除2例患者外,其他患者所需的充气量也均高于采用SLMA时。PLMA通气罩位置的FOB评分显著低于SLMA(P<0.05)。采用PLMA维持气道的29例患者和采用SLMA维持气道的21例患者的平均呼潮气量、吸气峰压及维持气道时间差异均无显著性(P均>0.05)。结论与SLMA相比,PLMA可为正压通气提供更好的气道密封压,而且对声门和食管上端具有潜在的隔离作用,用于正压通气时PLMA比SLMA更有效、更安全。     

The laryngeal mask airway: a comprehensive review for the Emergency Physician

The Laryngeal Mask Airway (LMA) was developed in the 1980s, but has only recently begun to be used in Emergency Medicine. The LMA affords effective assisted ventilation without requiring endotracheal intubation or visualization of the glottis. In doing so, it is more efficacious than a bag-valve-mask apparatus, although the risk of aspiration of gastric contents persists, particularly if the device is not properly placed. The LMA also has significant potential utility in management of the difficult airway. Most reported clinical experience with the LMA has come from the operating room. This article provides an overview of the extensive potential utility of the LMA in the Emergency Department and prehospital settings as well as a comprehensive review of the pertinent advantages, disadvantages, and complications associated with its use.     

The use of a laryngeal mask airway during percutaneous tracheostomy

Summary

Bedside percutaneous tracheostomy (PCT) for patients in intensive care units (ICU) is gaining popularity. Recently, the use of a laryngeal mask airway (LMA) to facilitate PCT has been described. We present a series of 18 patients where an LMA was inserted prior to PCT. This was successful in all but one patient. PCT could not be performed in this patient as oxygen desaturation had developed after inserting the LMA. The reason for this was probably an oedematous larynx, secondary to long-term intubation. Major bleeding in two patients [one of whom required packed red blood cell (RBC) transfusion] required surgical intervention and two patients had minor bleeding. No complications were related to the insertion or presence of the LMA during PCT, with the exception of the one patient cited above. The use of an LMA during PCT is a method of treatment worth noting in ICU patients. This technique may provide suitable conditions for performing PCT and is free from the complications associated with the presence of an endotracheal tube.     

Laryngeal mask anesthesia in children: a case report

The laryngeal mask airway has become one of the major tools of modern anesthesia airway management. Despite the fact that no time limit has been recommended regarding its safe use in spontaneously breathing children, or adults, there is still reluctance to use the laryngeal mask airway in operations of long duration. We report the case of an uneventful 5-hour long laryngeal mask anesthesia in a spontaneously breathing 11-year-old boy undergoing lower limb surgery.     

The use of the laryngeal mask airway with mechanical positive pressure ventilation

The purpose of this article is to discuss the benefits, safety, and efficacy of the laryngeal mask airway (LMA) and identify the risks and misconceptions associated with LMAs when used with positive pressure ventilation (PPV). Despite the abundance of supporting evidence that LMAs may be used successfully in a variety of age groups and surgical procedures using PPV, many anesthesia providers are still reluctant to choose an LMA when PPV is needed. This reluctance emerges from the misconception that when using an LMA with mechanical ventilation, there is an increased incidence of gastric insufflation, failed ventilation, and pulmonary aspiration. When compared to other airway adjuncts, however, the LMA is a safe, effective means of delivering ventilation under anesthesia.     

Use of the intubating laryngeal mask airway in the emergency department: A ten-year retrospective review

BackgroundExtraglottic devices, such as the intubating laryngeal mask airway (ILMA), facilitate ventilation and oxygenation and are useful for emergency airway management, especially as rescue devices. In the operating room setting the ILMA has been highly successful. However, its performance in the ED has not been described. We sought to describe the indications for and success of the ILMA when used in the ED.MethodsWe performed retrospective, observational study of patients who had an LMA® Fastrach™ (hereafter termed ILMA) placed in a single ED between 2007 and 2017. Patients were identified by keyword search of ED notes in the electronic medical record. Trained abstractors reviewed charts and videos to determine patient characteristics, indication for ILMA placement, success of oxygenation and ventilation, intubation methods and success, and complications related to the device.ResultsDuring the study period 218 patients had an ILMA placed in the ED. The ILMA was used as a primary device in 118 patients (54%), and as a rescue device in 100 patients (46%). The median number of ILMA uses per faculty physician during the study period was 3. The ILMA oxygenated and ventilated successfully in 212 instances (98%), including 96 times (96%) when used as a rescue airway. Failure of oxygenation was due to tracheal injury (2), abnormal laryngeal inlet anatomy (2), or poor operator technique (1). Intubation through the ILMA was successful in 159 of 192 patients (83%), including a success rate of 81% (112 of 139 patients) with blind intubation.ConclusionThe ILMA was highly successful in oxygenation, with reasonable intubation success, even when used infrequently by emergency physicians. The ILMA should be considered a valuable primary and rescue intubation device in the ED.