Use of the intubating laryngeal mask airway in emergency pre-hospital difficult intubation

AIM OF THE STUDY: While several techniques are used for the management of difficult intubation (DI) in planned conditions in the operating theatre, they are not always suitable or usable in pre-hospital emergencies. We decided to assess the intubating laryngeal mask airway (ILMA) after failure of tracheal intubation (TI) under direct laryngoscopy. MATERIAL AND METHODS: After emergency physicians of the mobile intensive care unit were trained (theory and training on manikin) in using the ILMA (Fastrach), prospective data were collected after each use from March 2002 to December 2005. Data included patient's age, clinical status, number of direct laryngoscopies before using ILMA, Cormack and Lehane grade, subjective and objective evaluation of ease of ILMA insertion and TI (analogue scale from 1 to 10, attempts required, failure rate). RESULTS: Over 46 months, the ILMA was used 45 times (24: cardio-respiratory arrest, 21: anaesthesia with rapid sequence induction). Median age was 59 years [range 20-86]. The number of direct laryngoscopy attempts was 3 [0-4] (76% Cormack 4). The success of ILMA insertion and TI were 96 and 91%, respectively. CONCLUSION: Emergency physicians were satisfied with using the ILMA. It allowed TI in 91% of cases of DI. The ILMA can be recommended to be included in the algorithm of DI in pre-hospital emergencies after initial training.     

Emergency airway management by intensive care unit nurses with the intubating laryngeal mask airway and the laryngeal tube

When using the laryngeal tube and the intubating laryngeal mask airway (ILMA), the medium-size (maximum volume 1100 ml) versus adult (maximum volume 1500 ml) self-inflating bags resulted in significantly lower lung tidal volumes. No gastric inflation occurred when using both devices with either ventilation bag. The newly developed medium-size self-inflating bag may be an option to further reduce the risk of gastric inflation while maintaining sufficient lung ventilation. Both the ILMA and laryngeal tube proved to be valid alternatives for emergency airway management in the experimental model used.     

Use of the intubating laryngeal mask airway in pre-hospital care: a case report.

In trauma management, the importance of early and effective control of the airway is acknowledged universally. Attention to the airway is particularly vital when a casualty has sustained serious head or facial injuries. A cuffed tracheal tube has generally been regarded as the airway adjunct of choice in such cases. However, the attempted insertion of a tracheal tube under direct laryngoscopy is associated with a number of practical problems in pre-hospital trauma care. A case is described in which the intubating laryngeal mask airway (ILMA or LMA-Fastrach) was used successfully in the pre-hospital setting to secure the airway of a patient who had sustained serious head and facial injuries in a road traffic collision. The indications for the use of the ILMA in pre-hospital care are discussed.     

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.     

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.     

Emergency airway management with laryngeal mask airway

When used correctly, laryngeal mask airway is a life saver. We report two cases wherein it was used for rescue airway management and as a ventilatory device during anesthesia. It is concluded that an anesthetist should be familiar with the use of this device.     

Pulse oximetry with the laryngeal mask airway

This study evaluated the accuracy of pulse oximetry measured by a modified laryngeal mask airway (LMA). Ten anaesthetized patients (ASA I-II, aged 18-45) undergoing elective knee arthroscopies (mean-duration 40 min) were studied. A transmission pulse oximeter probe/sound OHMEDA was attached on the back of LMA (sizes 4 and 5) in an area in contact with the floor of the laryngeal part of the pharynx. Pharyngeal pulse oximetry as well as LMA cuff pressure were monitored and recorded every 5 min from the time of insertion (T0) to removal (T8) and were compared to simultaneous finger pulse oximeter readings. At T2 the cuff was over-inflated to obtain a 100 cm H2O intracuff pressure. At T3 the cuff pressure was decreased at 60 cm H2O. Pharyngeal pulse oximetry correlated with finger pulse oximetry throughout the study and was not effected by over-inflation of the LMA. This modification of the LMA provides an accurate method of measuring pulse oximetry which may be of use in a variety of circumstances.     

A comparison of the I-gel supraglottic airway as a conduit for tracheal intubation with the intubating laryngeal mask airway: A manikin study

Background

Insertion of a supraglottic airway and tracheal intubation through it may be indicated in resuscitation scenarios where conventional laryngoscopy fails. Various supraglottic devices have been used as conduits for tracheal intubation, including the intubating laryngeal mask airway (ILMA), the Ctrach™ laryngeal mask and the I-gel supraglottic airway.

Methods

A prospective study with 25 participants evaluated the success rate of blind intubation (using a gum-elastic bougie, an Aintree intubating catheter (AIC) and designated tracheal tube) and fibrescope-guided tracheal intubation (through the intubating laryngeal mask airway and the I-gel supraglottic airway) on three different airway manikins.

Results

Twenty-five anaesthetists performed three intubations with each method on each of three manikins. The success rate of the fibrescope-guided technique was significantly higher than blind attempts (P < 0.0001) with both devices. For fibreoptic techniques, there was no difference found between the ILMA and I-gel (P > 0.05). All blind techniques were significantly more successful in the ILMA group compared to the I-gel (P < 0.0001 for bougie, Aintree catheter and tracheal tube, respectively).

Conclusions

The results of this study show that, in manikins, fibreoptic intubation through both ILMA and I-gel is a highly successful technique. Blind intubation through the I-gel showed a low success rate and should not be attempted.     

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。     

Remifentanil and etomidate for laryngeal mask airway insertion

Etomidate does not depress the upper airway reflexes, making it difficult to insert a laryngeal mask airway (LMA) when using it for anaesthesia. This study investigated the effect of adding remifentanil to etomidate for LMA insertion. Fifty adult patients, undergoing cystoscopy, were randomized to two groups. The propofol-remifentanil group (n=25) received propofol anaesthesia induction (2.5 mg/kg) and a remifentanil bolus of 0.5 microg/kg, followed by a 2-min remifentanil infusion of 0.05 microg/kg per min. The etomidate-remifentanil group (n=25) received etomidate anaesthesia induction (0.3 mg/kg) and remifentanil as described. The LMA was inserted by a blinded anaesthetist who assessed a number of parameters. Only 13 LMAs were inserted at the first attempt in the etomidate-remifentanil group compared with 23 in the propofol-remifentanil group. Gagging, chest rigidity and myoclonus occurred significantly more frequently in the etomidate-remifentanil group. We conclude that the addition of remifentanil to etomidate anaesthesia induction does not improve LMA insertion.     

The laryngeal mask airway in emergency medicine

The Laryngeal Mask Airway (LMA) is an upper airway adjunct lying intermediate in function between the endotracheal tube and the oropharyngeal airway. It has gained wide acceptance since its introduction into United Kingdom anaesthetic practice in 1988. We review the principles of advanced airway management in the emergency department and examine the application of the LMA to this area. We conclude that the LMA may have a small role in pre-hospital and CPR airway management, and a very significant role in the management of difficult or failed endotracheal intubation.