Skip Navigation LinksHome > July 2007 - Volume 14 - Issue 3 > Laryngeal Mask Airway: Use and Clinical Applications
Journal of Bronchology:
doi: 10.1097/LBR.0b013e3181132119
Review Articles

Laryngeal Mask Airway: Use and Clinical Applications

Sung, Arthur MD*; Kalstein, Allisoin DO; Radhakrishnan, Palangat MD; Yarmush, Joel MD; Raoof, Suhail MD*

Free Access
Article Outline
Collapse Box

Author Information

*Division of Pulmonary and Critical Care Medicine

Department of Anesthesiology, New York Methodist Hospital, Brooklyn, NY

There is no conflict of interest.

Reprints: Arthur Sung, MD, Division of Pulmonary and Critical Care Medicine, New York Methodist Hospital, 506 sixth street, Brooklyn, NY 11215-9008 (e-mail: ars9028@nyp.org).

Received for publication April 30, 2007; accepted May 14, 2007

Collapse Box

Abstract

The laryngeal mask airway (LMA) provides a safe and effective method of securing an airway in anesthesia and critical care settings. Although the classic LMA provides an airtight seal over the glottic opening to provide effective gas exchange, several modifications, additions, and variations have been developed and are currently in use. In particular, the Fastrach LMA, through which an endotracheal tube can be introduced, provides an alternative method for intubation in a difficult airway patient. LMAs can also be life-saving in facilitating a temporary airway in the field or for interhospital transport. Additionally, LMAs can be used during bronchoscopies and various airway procedures, such as percutaneous dilatational tracheostomies. Although the LMA has gained popularity owing to its ease of learning and usage, potential risks and complications exist. Therefore, thorough knowledge of its properties and indications for use is essential.

Back to Top | Article Outline

INVENTION AND DEVELOPMENT

In 1878, Dr William Macewan, a surgeon in Glasgow, first described the use of endotracheal tubes (ETTs) instead of performing tracheostomies. However, performing endotracheal intubations did not become common practice until Dr Ivan Magill introduced blind nasotracheal intubations during the First World War. Today, endotracheal intubations have become routine in the anesthesia and critical care settings. Indeed, an ETT is the most effective and safe method of securing an airway. However, the realization that other less invasive devices can be used in a wide number of situations prompted a search for a suitable alternative. Such a device should be supraglottic in order to be less invasive and at the same time, be able to produce an airtight seal over the glottic opening to make gas exchange effective. The most important and widely used supraglottic device today is the laryngeal mask airway (LMA).

The inventor of the LMA is Dr Archie Brain, an anesthesiologist from the United Kingdom. Development started on the LMA in 1981 and was available for commercial use, in the United States, by 1992. Since its introduction, several modifications, additions, and variations have been developed, and are currently in use.

Back to Top | Article Outline

MASK TYPES

Classic LMA

The classic LMA consists of a tube with an inflatable mask (Fig. 1). The entire apparatus is latex free with a silicone rim. The mask is a flattened, pear-shaped, inflatable cuff with an open front. If properly positioned, the opening overlies the glottis and the proximal end opposes the base of the tongue and the distal rim wedges against the upper esophageal sphincter, making a seal. The classic LMA is autoclavable and reusable. Its total usage has been estimated to be approximately 200 million patient uses since its introduction to clinical practice.1

Figure 1
Figure 1
Image Tools
Back to Top | Article Outline
ProSeal LMA
Equation (Uncited)
Equation (Uncited)
Image Tools

The ProSeal LMA was released in the year 2000 and is a modified version of the classic LMA.2 In addition to the silicone rim intended to obtain a seal around the larynx, the distal tip has an esophageal drainage port designed to communicate with the gastrointestinal tract. The port permits suctioning, potentially decreasing the risk of gastric content aspiration. Its insertion time is slightly longer when compared with the classic LMA, but shows a 50% improvement in obtaining a proper seal.3 If the device is placed too proximal or there is a leak, air is detected from the esophageal port. Many nonconventional techniques for insertion of the ProSeal LMA have been described,4–6 offering options for the operator when confronted with a difficult airway in the adult or pediatric population.7 Potential problems may include malpositioning,8 laryngeal edema,9 and airway obstruction. Complications regarding LMAs in general are discussed later.

Back to Top | Article Outline
Intubating LMA, Fastrach

The Intubating LMA (iLMA) is a modified version of the classic LMA with the upper part of the tube removed. The remaining tube has a metallic core with a handle used for positioning at its proximal end (Fig. 2). After establishing an airway with the iLMA, an ETT can be introduced through the metallic channel. It has been incorporated into the difficult airway management algorithms.10,11 It is easy to use and may be life-saving. In a study using manikin models, both experienced and nonexperienced operators were able to achieve high intubation success rates on the first attempt after having a 60-second demonstration.12

Back to Top | Article Outline
C-Trach LMA
Figure 2
Figure 2
Image Tools

Last year, a modified iLMA incorporating fiberoptics to provide a real-time view of the glottis was developed.13 It is intended for the difficult airway, and a study looking at its utility in intubating obese patients demonstrated initial favorable success rates.14

Equation (Uncited)
Equation (Uncited)
Image Tools
Back to Top | Article Outline
Disposable LMAs

There are 3 main types of disposable LMAs. These include the LMA-Unique, the Portex Soft-Seal, and the Ambu laryngeal mask (now called the AuraOnce). The LMA unique is very similar to the Classic reusable LMA (Fig. 3). The Portex Soft Seal does not have the silicone rim. The Ambu-laryngeal mask (Fig. 4) has a rigid curve in the main tube in order to better conform to the oropharyngeal anatomy. Most studies of these devices are small and investigate the time of insertion and safety. Brimacombe et al15 compared the LMA-unique and the Soft-Seal, and found that the LMA-unique is easier to insert and allows for better glottic positioning. All 3 were compared recently by Francksen et al.16 All were fairly similar in clinical use, ease of insertion, and success rate; the Ambu laryngeal mask having the shortest insertion time.16

Back to Top | Article Outline

GUIDE TO USE

Insertion Techniques
Figure 3
Figure 3
Image Tools
Figure 4
Figure 4
Image Tools

All LMAs consist of 2 parts, a hollow tube continuous with a hollow mask. The pear-shaped mask has an open front and closed back. An aperture bar extends across the open front to prevent obstruction of the tube by the epiglottis. The backside is lubricated and makes contact with the palate and pharynx during insertion.

Equation (Uncited)
Equation (Uncited)
Image Tools

Standing above the supine patient's flexed neck and extended head; the tube is grasped with the dominant hand as near to the mask as possible, as you would hold a pen. The deflated flattened mask is inserted against the hard palate downward into the mouth following the contour of the back of the pharynx to get behind and under the tongue to finally seat at the entrance to the larynx. The index finger follows the tube into the mouth to keep pressing “back” and “down” until the apparatus is properly seated in the pyriform fossa (Fig. 5). An alternative to intraoral manipulation is to allow the dominant hand to guide the tube when the mouth is reached and use the nondominant hand to push the tube with or without an introducer.17–19 Several manuals and videotapes demonstrating the proper techniques are available.20–23

Equation (Uncited)
Equation (Uncited)
Image Tools

It is important to quickly assess proper placement of the airway. Cuff inflation pressure should not exceed 60 mm Hg and adequate tidal volumes should be achieved with minimal leak. If the mask is malpositioned, the mask may have to be replaced and other maneuvers tried. Using a partially or fully inflated cuff may facilitate insertion.24–26 Wakeling et al24 claims that insertion with a fully inflated cuff causes less mucosal trauma and hence fewer postoperative sore throats. Brimacombe26 refutes this assertion. These maneuvers may not only aid in insertion but also increase morbidity. If available, a second operator can apply a jaw thrust maneuver. This moves the tongue forward and out of the way and also prevents compression of the epiglottis.27 If a second operator is unavailable, then a tongue depressor or even laryngoscopy can be used to reposition the tongue.28

Another maneuver for difficult placement is to stand facing the patient. This may facilitate placement because the action of the dominant hand is now “forward” rather than “backward.” This technique can be used if the patient is in the sitting or semi-reclining positions or when neck flexion and head extension is undesirable.

The mask fit is also dependent on the size of the cuff and the volume of air used to fill it. The maximum volume of air, which can be used for cuff inflation, is written on the LMA with inflation pressure not to exceed 60 mm Hg (Table 1). Dr Brain, in his 1991 manual,29 asserts that a better seal is obtained by using the largest size cuff possible. If the mask is too small, the cuff will have to be overinflated to form a seal, which may lead to malposition. There is controversy whether the larger mask with less inflation decreases30 or increases31 postoperative morbidity such as sore throat.

Weight-based selection has given way to sex-based selection, especially in adults (Table 1). Asai and Brimacombe32 have summarized many studies that have looked at this issue. The consensus seems to be that using a size 3 for most adult women and size 4 for most adult men is inadequate. The correct size would be a size 4 for most adult women and a size 5 for most adult men. Whatever the initial size selected, if malposition or an inadequate seal is present, a larger size LMA should be considered.

Figure 5
Figure 5
Image Tools

A priori identification of a difficult LMA insertion may be problematic. A smaller than desired LMA may be used because of a small mouth opening. Mallampati class, used to identify difficult intubations, may or may not herald difficult LMA placement. A study by Brimacombe and Berry33 indicated that LMA placement does not correlate with Mallampati class whereas a study by McCrory and Moriarty34 indicates that there is a positive correlation.

Equation (Uncited)
Equation (Uncited)
Image Tools

We suggest that if repeated attempts with one type of LMA are unsuccessful, changing to another type or even a third type, may work. No studies looking at this phenomenon have been conducted.

Back to Top | Article Outline
Training

One of the reasons that laryngeal masks have gained in popularity is because successful placement is easily learned. However, we caution its routine use by personnel untrained in airway management. None of the studies claim 100% successful placement and alternate airway management maneuvers may be necessary.

Table 1
Table 1
Image Tools

Many studies have looked at the ease of training with medical providers who have little experience with airway management.35–40 It seems clear that training using a manikin is sufficient to master the basics of LMA use. Further, studies have demonstrated that these basics only need a brief training period.

However, not all manikins are the same. Silsby et al41 evaluated 4 different manikins for teaching LMA use. They concluded that 3 (ie, Bill 1, Airsim, and Airway Trainer) of the 4 manikins offered an acceptable training experience whereas the Airway Management Trainer was rated as not acceptable. Hesselfeldt et al42 evaluated Simman, a full patient simulator, and it was judged acceptable for training with a LMA. Parry and Owen43 tested many manikins and found that most would be acceptable or good for training with a LMA.

Tiah et al44 advocate that airway management training should be emphasized in medical school. They found that medical students were able to place the LMA the quickest, with reproducibility, when compared with other airway devices including the Combitube and the ETT.

Back to Top | Article Outline
Effect on Physiologic Response

Another reason the LMA has gained in popularity is because of its diminished physiologic response as compared with insertion of an ETT. Many studies have shown that the changes in heart rate and blood pressure are significantly lessened with insertion of a laryngeal mask as compared with insertion of an ETT or comparable invasive device.45–48 The hemodynamic changes are similar if a LMA and a less invasive device (eg, cuffed oropharyngeal airway) are compared.49

Insertion of a LMA minimizes other effects as well. Insertion does not cause an increase in intraocular pressure50–52 and Agarwal and Shobhana53 imply that insertion does not raise ICP.

Back to Top | Article Outline

COMPLICATIONS

To an untrained observer, the insertion of the LMA may seem to be a simple procedure. However, incorrect insertion techniques account for many of the problems associated with its use.

Optimal position of the mask at the laryngeal inlet allows gas exchange to take place without hindrance and may also allow ventilation using positive pressure. An improperly placed LMA causes leakage of gas around the cuff especially when using positive pressure. Malposition of the LMA may not always be apparent54 and a flexible bronchoscope may be needed to check the position of the aperture.28

The risk of gastric distension, gastroesophageal reflux, and tracheal soiling may be increased with incorrect positioning especially if positive pressure is used. Several studies, however, have showed that if an LMA was placed properly, the risks of gastric distention55,56 and gastroesophageal reflux57 were not increased compared with an ETT. Cassu et al58 showed that the use of an LMA in ventilated cats may cause reflux but no aspiration.

Haslam et al59 reported a case of gastric rupture during cardiopulmonary resuscitation attributed to LMA use. Nolan et al60 refute this.

Trauma to the soft tissues during placement of the LMA is not an uncommon occurrence and blood may frequently be noticed on removing the LMA. Folding of the tip of the LMA over itself, use of undue force, wrong technique, or inadequate depth of anesthesia is often to blame for these mishaps. Trauma to the uvula and the posterior pharyngeal wall have been reported.61 Several instances of nerve paralyses including paralysis of the lingual nerve, hypoglossal nerve, glossopharyngeal nerve, and recurrent laryngeal nerve have been reported. Brimacombe et al62 review many of these cases. Swelling of the tongue, cyanosis of the tongue, arytenoid cartilage dislocation, temporomandibular joint dislocation, and vocal cord dysfunction have all been reported. At least some of these complications may be attributed to high cuff pressures or prolonged duration of use of the LMA.

Bronchospasm, laryngospasm, stridor, and partial or total airway obstruction may be encountered and may be related to depth of anesthesia or the noxiousness of the surgical stimulus. Though many of these complications may be amenable to deepening of anesthesia or the use of a muscle relaxant, occasionally, replacement of the LMA with an ETT may be necessary. Coughing, bucking, and biting down on the LMA are also seen often during emergence from anesthesia. However, for the most part the LMA is fairly well tolerated even during emergence and removal is accomplished after simply asking the patient to open his or her mouth.

Back to Top | Article Outline

USES OF LMA FOR AIRWAY MANAGEMENT

The LMA may be used in the spontaneously breathing patient with adequate sedation and topical anesthesia, or the paralyzed, anesthetized patient with assisted mechanical ventilation. It can be used in many situations, such as bronchoscopic procedures performed in the endoscopy setting, elective surgeries in the ambulatory clinics, procedures in the critical care units, as well as in the field outside of the hospital with emergency care providers and first responders.

Back to Top | Article Outline
As a Substitute for a Facemask

Anesthesiologists have viewed the LMA as a substitute for a facemask in many situations. LMAs are especially useful when mask fit is difficult as in edentulous or bearded patients. They also serve to free up the anesthesiologist's hands so that one can attend to other essential tasks simultaneously.

Back to Top | Article Outline
Pediatric Bronchoscopies

Diagnostic and interventional procedures of the airway are becoming common among pediatric pulmonologists. Flexible bronchoscopies comprise the major airway procedures performed including bronchoalveolar lavage, transbronchial biopsies, and foreign body removal.63 Complications are rare but include hypoxemia, laryngospasm, bronchospasm, and local trauma.64 A laryngeal mask is a preferred technique for controlling the airway in the pediatric population compared with the adult population owing to the difference in body size, airway diameter, and lesser tolerance to conscious sedation.65 When bronchoscopy is performed, LMAs provide a safe alternative with minimal complication as compared with nasal route or endotracheal intubation.64,66–68 LMA use during pediatric bronchscopies is associated with ease of insertion, patient comfort during general anesthesia with spontaneous or assisted ventilation, as well as a net decrease in procedure time.67 As a laryngeal mask is a supraglottic device, its utility in aiding the diagnosis of subglottic pathologies has been demonstrated.69

Back to Top | Article Outline
Adult Bronchoscopies

The majority of adult diagnostic bronchoscopies are performed on spontaneously breathing patients under conscious sedation. Therefore, general anesthesia is not usually required. However, certain patients who cannot tolerate the procedure even with conscious sedation (ie, excessive gag response or discomfort) may require general anesthesia. A laryngeal mask is an ideal device to establish an airway. It is fairly noninvasive and its proper positioning can be easily ensured with the flexible bronchoscope. Additionally, new technologies in diagnostic bronchoscopy may, under specific circumstances, benefit from a deeply sedated or even generally anesthetized patient. For example, electromagnetic navigation bronchoscopy is a technology used to sample small peripheral lesions, such as solitary pulmonary nodules. The technology is safe with improved accuracy over conventional bronchoscopy70 but its precision has not been compared between the moderately sedated, spontaneously breathing patient and the deeply sedated or anesthetized patient. Using the LMA in this outpatient procedure would facilitate navigation to the periphery as well as during actual acquirement of tissue. Further, the anesthesiologist may be able to manipulate the respiratory cycle to improve the diagnostic accuracy. However, the use of a laryngeal airway has not been investigated and may obviate the intended benefit of the minimal invasive nature of the procedure.

Therapeutic bronchoscopies are becoming common place in the armamentarium of interventional pulmonologists. Tools such as self-expanding metallic stents,71 photoablation techniques for tumor ablation or hemoptysis, and foreign body retrieval can be life-saving. The anesthesia for these procedures is also evolving, as they are traditionally performed with general anesthesia and rigid bronchoscopies.72 In proximal central airway lesions, LMAs as supraglottic devices can be used for therapeutic intervention, while providing a secure airway in the anesthetized patient.

Back to Top | Article Outline
Percutaneous Tracheostomies

Bedside percutaneous tracheostomies are performed increasingly in the intensive care setting. The majority of percutaneous tracheostomies are indicated in patients who are dependent on mechanical ventilation owing to acute illnesses, or if duration of endotracheal intubation is anticipated to be more than 2 weeks.73 The recommended technique is performed with the bronchoscope at the proximal end of the ETT, and withdrawing it to above the first tracheal ring. The bronchoscope assists in visualizing the needle and guidewire being introduced into the lumen of the trachea, with subsequent dilatation with a conic dilator for the creation of the stoma. Once the proper placement of the tracheostomy tube is confirmed, the ETT can then be safely removed. A retrospective study by Cattano et al74 reviewed patients who underwent percutaneous tracheostomy with a dilating forceps approach after the ETT was replaced by a LMA. They felt that the supraglottic device offered a superior view of the proximal trachea without the risk of needle puncturing equipment such as the bronchoscope or the ETT. The study did not demonstrate increased risks such as bleeding. An earlier prospective study comparing LMA versus ETT for percutaneous tracheostomies found less hypercarbia with the LMA.75 However, concerns of aspiration of gastric contents and other potential complications remain. A study by Ambesh et al76 found significantly more complications with the LMA as compared with an ETT. Therefore, more studies are needed to address both efficacy and safety of this approach before recommendations can be made for LMA-assisted airway management for percutaneous tracheostomies.

Back to Top | Article Outline
Aiding Endotracheal Intubation by Flexible Bronchoscopy

Alternative and contingent options are needed when facing a difficult airway. As mentioned, the iLMA has provided an important option for the clinician. Although LMAs are designed as blind intubating devices, newer approaches have been reported to incorporate the flexible bronchoscope for airway management (Fig. 6). For example, the Aintree catheter has been incorporated with the ProSeal LMA in facilitating the endotracheal intubation. After the placement of the LMA, a bronchoscope fitted with the Aintree catheter is directed into the LMA and through the glottis, and subsequent placement of the ETT using the catheter as the guidewire.4 In the pediatric literature, combining the flexible bronchoscope with the LMA for intubating the difficult airway has also been described.65,77

Back to Top | Article Outline
Pre or Outside the Hospital Airway

In the field, securing an airway may be paramount. In the “can't ventilate, can't intubate” situation, the LMA may be lifesaving. A LMA can be used for transport until a definitive airway can be obtained.78 An iLMA can also be used, as a 6-mm internal diameter ETT may be easily inserted. As stated before, the basics of LMA placement is easily mastered with limited training.

Case reports of infants with laryngotracheoesophageal clefts and an infected neonate showed the ability to use the LMA for interhospital transport.79

During CPR, the first part of the secondary survey includes securing an airway device as soon as possible.80 In the event that the patient cannot be ventilated or intubated easily, or if the patient is in a difficult position where there is limited space to perform direct laryngoscopy, then the LMA can be a backup device for securing the airway. Keller et al81 demonstrated increased vertebral pressures in a cadaver study using an LMA as compared with an ETT. They suggest that an LMA should be used with caution in an unstable neck. Todd and Traynelis82 question the clinical validity of the study.

Back to Top | Article Outline

CONCLUSION

Figure 6
Figure 6
Image Tools

Since its introduction, the LMA has offered anesthesiologists and other physicians who manage airways as an important option in their armamentarium. Different designs give specific advantages for different clinical scenarios. Insertion can be learned with ease, and nonphysicians are capable of securing an airway with adequate training. Knowing the indications and contraindications of using a LMA is paramount to its appropriate usage, as complications are distinct from endotracheal intubations owing to its inherent design and position as a supraglottic airway. Its applications are growing with its recognized advantages, in outpatient, inpatient, and the critical care environment. Increasing recognition of a LMA's applications should expand its role in airway management for the anesthesiologist and the bronchoscopist.

Equation (Uncited)
Equation (Uncited)
Image Tools
Back to Top | Article Outline

ACKNOWLEDGMENT

The authors thank Dr Alexey Amchentsev for his technical assistance during the preparation of this manuscript.

Back to Top | Article Outline

REFERENCES

1. Cook TM. The classic laryngeal mask airway: a tried and tested airway. What now? Br J Anaesth. 2006;96:149–152.

2. Brain AIJ, Verghese C, Strube PJ. The LMA ‘ProSeal’—a laryngeal mask with an oesophageal vent. Br J Anaesth. 2000;84:650–654.

3. Cook TM, Lee G, Nolan JP. The ProSealTM laryngeal mask airway: a review of the literature. Can J Anaesth. 2005;52:739–760.

4. Cook TM, Seller C, Gupta K, et al. Non-conventional uses of the Aintree Intubating Catheter in management of the difficult airway. Anaesthesia. 2007;62:169–174.

5. Critchley LA, Khaw KS. Bougie assisted insertion of ProSealTM LMA. Anaesth Intensive Care. 2006;34:514–515.

6. Brimacombe J, Keller C. Successful guided insertion of a ProSealTM LMA in a patient with limited mouth-opening after failed insertion of a flexible LMA. Anaesth Intensive Care. 2005;33:823–824.

7. Wheeler M. ProSealTM laryngeal mask airway in 120 pediatric surgical patients: a prospective evaluation of characteristics and performance. Paediatr Anaesth. 2006;16:297–301.

8. O'Connor CJ Jr, Stix MS, Valade DR. Glottic insertion of the ProSeal LMA occurs in 6% of cases: a review of 627 patients. Can J Anaesth. 2005;52:199–204.

9. Chin KJ, Chee VW. Laryngeal edema associated with the ProSeal laryngeal mask airway in upper respiratory tract infection. Can J Anaesth. 2006;53:389–392.

10. American Society of Anesthesiologists Task Force on Management of the Difficult Airway. Practice guidelines for management of the difficult airway: an updated report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway. Anesthesiology. 2003;98:1269–1277.

11. Henderson JJ, Popat MT, Latto IP, et al. Difficult Airway Society guidelines for management of the unanticipated difficult intubation. Anaesthesia. 2004;59:675–694.

12. Levitan RM, Ochroch EA, Stuart S, et al. Use of the intubating laryngeal mask airway by medical and nonmedical personnel. Am J Emerg Med. 2000;18:12–16.

13. Liu EH, Goy RW, Chen FG. The LMA CTrach, a new laryngeal mask airway for endotracheal intubation under vision: evaluation in 100 patients. Br J Anaesth. 2006;96:396–400.

14. Dhonneur G, Ndoko SK, Yavchitz A, et al. Tracheal intubation of morbidly obese patients: LMA CTrach vs. direct laryngoscopy. Br J Anaesth. 2006;97:742–745.

15. Brimacombe J, von Goedecke A, Keller C, et al. The laryngeal mask airway Unique versus the Soft Seal laryngeal mask: a randomized, crossover study in paralyzed, anesthetized patients. Anesth Analg. 2004;99:1560–1563.

16. Francksen H, Bein B, Cavus E, et al. Comparison of LMA Unique, Ambu laryngeal mask and Soft Seal laryngeal mask during routine surgical procedures. Eur J Anaesthesiol. 2007;24:134–140.

17. Brimacombe J, Keller C. Insertion of The Lma-UniqueTM with and without digital intraoral manipulation by inexperienced personnel after manikin only training. J Emerg Med. 2004;26:1–5.

18. Dingley J, Baynham P, Swart M, et al. Ease of insertion of the laryngeal mask airway by inexperienced personnel when using an introducer. Anaesthesia. 1997;52:756–760.

19. Omi A, Fukuhara T, Isshiki A, et al. The effectiveness of the Fukuhara laryngeal mask airway holding forceps (F Forceps). Anesth Analg. 1997;85:697–700.

20. Brain A, Denman WT, Goudsouzian NG. Laryngeal mask airway instruction manual. San Diego, CA: LMA North America Inc; 1999.

21. Brimacombe JR, Brain A. The laryngeal mask airway: a review and practical guide. London: WB Saunders; 1997.

22. Brain A. Insertion of laryngeal mask airway LMA. Internet J Anesthesiol. 2001;5:N3.

23. Palmer A. Insertion of a laryngeal mask airway; demonstration of the technique of insertion of a laryngeal mask airway. Internet J Anesthesiol. 1997;1:N3.

24. Wakeling HG, Butler PJ, Baxter PJ. The laryngeal mask airway: a comparison between two insertion techniques. Anesth Analg. 1997;85:687–690.

25. Matta BF, Marsh DS, Nevin M. Laryngeal mask airway: a more successful method of insertion. J Clin Anesth. 1995;7:132–135.

26. Brimacombe J. Laryngeal mask insertion techniques. Anesth Analg. 1998;86:1337–1338.

27. Aoyama K, Takenaka I, Sata T, et al. The triple airway manoeuvre for insertion of the laryngeal mask airway in paralyzed patients. Can J Anaesth. 1995;42:1010–1016.

28. Campbell RL, Biddle C, Assudme N, et al. Fiberoptic assessment of laryngeal mask airway placement: blind insertion versus direct visual epiglottoscopy. J Oral Maxillofac Surg. 2004;62:1108–1113.

29. Brain AJ. The Intavent Laryngeal Mask Instruction Manual. London: Intavent; 1991.

30. Brimacombe J, Holyoake L, Keller C, et al. Emergence characteristics and postoperative laryngopharyngeal morbidity with the laryngeal mask airway: a comparison of high versus low initial cuff volume. Anaesthesia. 2000;55:338–343.

31. Grady DM, McHardy F, Wong J, et al. Pharyngolaryngeal morbidity with the laryngeal mask airway in spontaneously breathing patients: does size matter? Anesthesiology. 2001;94:760–766.

32. Asai T, Brimacombe J. Review article: cuff volume and size selection with the laryngeal mask airway. Anaesthesia. 2000;55:1179–1184.

33. Brimacombe J, Berry A. Mallampati classification and LMA insertion. Anaesthesia. 1993;48:347.

34. McCrory CR, Moriarty DC. Laryngeal mask airway positioning is related to Mallampati grading in adults. Anesth Analg. 1995;81:1001–1004.

35. Guyette FX, Rittenberger JC, Platt T, et al. Feasibility of basic emergency medical technicians to perform selected advanced life support interventions. Prehosp Emerg Care. 2006;10:518–521.

36. Pennant JH, Walker MB. Comparison of the endotracheal tube and the laryngeal mask airway in airway management by paramedical personnel. Anest Analg. 1992;74:531–534.

37. Martin PD, Cyna AM, Hunter WAH, et al. Training nursing staff for resuscitation—a clinical comparison of the facemask and laryngeal mask. Anaesthesia. 1993;48:33–37.

38. Micaglio M, Doglioni N, Parotto M, et al. Training for neonatal resuscitation with the laryngeal mask airway: a comparison of the LMA-ProSealTM and the LMA-Classic in an airway management manikin. Paediatr Anaesth. 2006;16:1028–1831.

39. Coulson A, Brimacombe J, Keller C, et al. A comparison of the ProSealTM and classic laryngeal mask airways for airway management by inexperienced personnel after manikin-only training. Anaesth Intensive Care. 2003;3:286–289.

40. Gandini D, Brimacombe J. Manikin training for neonatal resuscitation with the laryngeal mask airway. Pediatric Anesthesia. 2004;14:493–494.

41. Silsby J, Jordan G, Bayley G, et al. Evaluation of four airway training manikins as simulators for inserting the LMA classic. Anaesthesia. 2006;61:576–579.

42. Hesselfeldt R, Kristensen MS, Rasmussen LS. Evaluation of the airway of the SimMan full-scale patient simulator. Acta Anaesthesiol Scand. 2005;49:1339–1345.

43. Parry K, Owen H. Small simulators for teaching procedural skills in a difficult airway algorithm. Anaesth Intensive Care. 2004;32:401–409.

44. Tiah L, Wong E, Chen MF, et al. Should there be a change in the teaching of airway management in the medical school curriculum? Resuscitation. 2005;66:245–246.

45. Wilson IG, Fell D, Robinson SL, et al. Cardiovascular responses to insertion of the laryngeal mask. Anaesthesia. 1992;47:300–302.

46. Fujii Y, Tanaka H, Toyooka H. Circulatory responses to laryngeal mask airway insertion or tracheal intubation in normotensive and hypertensive patients. Can J Anaesth. 1995;42:32–36.

47. Casati A, Vinciguerra F, Spreafico E, et al. Cardiovascular changes after extraglottic airway insertion: a prospective, randomized comparison between the laryngeal mask or the new PAXpress. J Clin Anesth. 2004;16:342–346.

48. Imai M, Matsumura C, Hanaoka Y, et al. Comparison of cardiovascular responses to airway management: fiberoptic intubation using a new adapter, laryngeal mask insertion, or conventional laryngoscopic intubation. J Clin Anesth. 1995;7:14–18.

49. Casati A, Cappelleri G, Fanelli G, et al. The pressor response after laryngeal mask or cuffed oropharyngeal airway insertion. Acta Anaesthesiol Scand. 1999;43:1053–1056.

50. Duman A, Ögün C, Ökelski S. The effect on intraocular pressure of tracheal intubation or laryngeal mask insertion during sevoflurane anaesthesia in children without the use of muscle relaxants. Paediatr Anaesth. 2001;11:421–424.

51. Eltzschig HK, Darsow R, Schroeder TH, et al. Effect of tracheal intubation or laryngeal mask airway insertion on intraocular pressure using balanced anesthesia with sevoflurane and remifentanil. J Clin Anesth. 2001;13:264–267.

52. Kilickan L, Baykara N, Gürkan Y, et al. The effect on intraocular pressure of endotracheal intubation or laryngeal mask use during TIVA without the use of muscle relaxants. Acta Anaesthesiol Scand. 1999;43:343–346.

53. Agarwal A, Shobhana N. LMA in neurosurgery. Can J Anesth. 1995;42:750.

54. Ball AJ. Laryngeal mask misplacement—a non problem. Anesth Analg. 1995;81:204.

55. Maltby RJ, Beriault MT, Watson NC, et al. Gastric distension and ventilation during laparoscopic cholecystectomy: LMA-Classic vs. tracheal intubation. Can J Anesth. 2000;47:622–626.

56. Maltby RJ, Beriault MT, Watson NC, et al. The LMA-ProSealTM is an effective alternative to tracheal intubation for laparoscopic cholecystectomy. Can J Anesth. 2002;49:857–862.

57. O' Brien B, Harmon D, Duggan M, et al. Laryngeal mask cuff inflation at removal does not affect early postoperative laryngopharyngeal morbidity. Can J Anesth. 2002;49:871–873.

58. Cassu RN, Luna SP, Teixeira Neto FJ, et al. Evaluation of laryngeal mask as an alternative to endotracheal intubation in cats anesthetized under spontaneous or controlled ventilation. Vet Anaesth Analg. 2004;31:213–221.

59. Haslam N, Campbell G, Duggan JE. Gastric rupture associated with use of the laryngeal mask airway during cardiopulmonary resuscitation. BMJ. 2004;329:1225–1226.

60. Nolan JP, Colquhoun M, Deakin CD. Gastric rupture and laryngeal mask airway: laryngeal mask airway was not likely cause of gastric rupture. BMJ. 2005;330:538.

61. Marjot R. Pressure exerted by the laryngeal mask cuff upon the pharyngeal mucosa. Br J Anesth. 1993;70:25–29.

62. Brimacombe J, Clarke G, Keller C. Lingual nerve injury associated with the ProSeal laryngeal mask airway: a case report and review of the literature. Br J Anaesth. 2005;95:420–423.

63. Swanson KL. Airway foreign bodies: what's new? Semin Respir Crit Care Med. 2004;25:405–411.

64. Nussbaum E. Pediatric fiberoptic bronchoscopy: clinical experience with 2,836 bronchoscopies. Pediatr Crit Care Med. 2002;3:171–176.

65. Niggemann B, Haack M, Machotta A. How to enter the pediatric airway for bronchoscopy. Pediatr Int. 2004;46:117–121.

66. Naguib ML, Streetman DS, Clifton S, et al. Use of laryngeal mask airway in flexible bronchoscopy in infants and children. Pediatr Pulmonol. 2005;39:56–63.

67. Nussbaum E, Zagnoev M. Pediatric fiberoptic bronchoscopy with a laryngeal mask airway. Chest. 2001;120:614–616.

68. Ernst A, Silvestri GA, Johnstone D. Interventional pulmonary procedures: guidelines from the American College of Chest Physicians. Chest. 2003;123:1693–1717.

69. Somri M, Barna Teszler C, Tome R, et al. Flexible fiberoptic bronchoscopy through the laryngeal mask airway in a small, premature neonate. Am J Otolaryngol. 2005;26:268–271.

70. Gildea TR, Mazzone PJ, Karnak D, et al. Electromagnetic navigation diagnostic bronchoscopy: a prospective study. Am J Respir Crit Care Med. 2006;174:982–989.

71. Lohser J, Brodsky JB. Bronchial stenting through a ProSeal laryngeal mask airway. J Cardiothorac Vasc Anesth. 2006;20:227–228.

72. Conacher ID. Anaesthesia and tracheobronchial stenting for central airway obstruction in adults. Br J Anaesth. 2003;90:367–374.

73. Heffner JE. Tracheotomy application and timing. Clin Chest Med. 2003;24:389–398.

74. Cattano D, Abramson S, Buzzigoli S, et al. The use of the laryngeal mask airway during guidewire dilating forceps tracheostomy. Anesth Analg. 2006;103:453–457.

75. Dosemeci L, Yilmaz M, Gurpinar F, et al. The use of the laryngeal mask airway as an alternative to the endotracheal tube during percutaneous dilatational tracheostomy. Intensive Care Med. 2002;28:63–67.

76. Ambesh SP, Sinha PK, Tripathi M, et al. Laryngeal mask airway vs. endotracheal tube to facilitate bedside percutaneous tracheostomy in critically ill patients: a prospective comparative study. J Postgrad Med. 2002;48:11–15.

77. Hung KC, Shiau JM, Yang YL, et al. Fiberoptic tracheal intubation through a classicial laryngeal mask airway under spontaneous ventilation in a child with Treacher Collins syndrome. Acta Anaesthesiol Taiwan. 2006;44:223–226.

78. Martin SE, Ochsner MG, Jarman RH, et al. Use of the laryngeal mask airway in air transport when intubation fails. J Trauma-Injury Infection Crit Care. 1999;47:352–357.

79. Trevisaunto D, Verghese C, Doghoni N, et al. Laryngeal mask airway for interhospital transport of neonates. Pediatrics. 2005;115:109–111.

80. The American Heart Association in Collaboration with the International Liaison Committee on Resuscitation. Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation. 2000;102(suppl 1):95–104.

81. Keller C, Brimacombe J, Keller K. Pressures exerted against the cervical vertebrae by the standard and intubating laryngeal mask airways: a randomized, controlled, cross-over study in fresh cadavers. Anesth Analg. 1999;89:1296.

82. Todd MM, Traynelis VC. Experimental cervical spine injury and airway management methods. Anesth Analg. 2001;93:799–800.

Keywords:

laryngeal mask airway; bronchoscopy; airway management

© 2007 Lippincott Williams & Wilkins, Inc.

Login

Article Tools

Images

Share

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.