View source for Supraglottic airway

==Indications==
[[File:F4.png|thumb|Oral cavity and oropharynx.]]
[[File:F6.png|thumb|Sagittal section through the head and neck showing the subdivisions of the pharynx.]]
[[File:F8.png|thumb|External views of the larynx: (a) anterior aspect; (b) anterolateral aspect with the thyroid gland and cricothyroid ligament removed.]]
[[File:Cartilages and ligaments of the larynx.png|thumb|The cartilages and ligaments of the larynx seen posteriorly.]]
*Need for positive pressure ventilation (PPV)
**Primary or rescue airway<ref name="Anesthesia">Apfelbaum JL, et al.; 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. 2013 Feb;118(2):251-70</ref>
**Conduit/guide for elective or rescue fiberoptic intubation<ref name="NAP4">Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Cook TM, Woodall N, Frerk C; Fourth National Audit Project. Br J Anaesth. 2011 May;106(5)</ref>
**Intubating LMA may be used to guide placement of an endotracheal tube
*Field intubation by paramedics, especially in pediatric patients<ref>Zhu X-Y, Lin B-C, Zhang Q-S, Ye H-M, Yu R-J. A prospective evaluation of the efficacy of the laryngeal mask airway during neonatal resuscitation. Resuscitation. 2011;82(11):1405–1409. doi:10.1016/j.resuscitation.2011.06.010</ref><ref>Calkins MD, Robinson TD. Combat trauma airway management: endotracheal intubation versus laryngeal mask airway versus combitube use by Navy SEAL and Reconnaissance combat corpsmen. J Trauma. 1999;46(5):927–932</ref>

==Contraindications==
===Absolute===
*Spontaneous respirations
*Gag reflex
===Relative===
*Significant facial trauma

===Difficult Supraglottic Device (RODS)===
*'''R'''estricted mouth opening
*'''O'''bstruction
*'''D'''istorted airway
*'''S'''tiff lungs (chronic pulmonary disease, obesity) or neck (C-spine collar, limited neck extension)

==Equipment Needed==
*Supraglottic Airway (SGA) device (many options exist, see below)
*Appropriate sedation/paralytic agents, if indicated

===[[LMA]] Sizes<ref>Tarascon Adult Emergency Pocketbook</ref>===
{{LMA sizes}}
===iGel Sizes===
{{igel sizes}}

==Procedure==
[[File:Masques laryngés- LMA Unique et I-gel.jpg|thumb|Two example LMA airways.]]
[[File:Laryngeal mask airway.jpg|thumb|LMA airway removed from packaging.]]
''Due to variety of devices and placement techniques, impossible to give exact universal procedure''

#Prepare patient as for intubation
#If patient is awake, provide topical anesthetic
#Place supraglottic airway device by one of the following techniques:
#*Use thumb or index finger to guide device along midline of hard palate with cuff deflated or partially inflated and advance until seated
#*Insert device with cuff facing hard palate, then rotate 180 degrees while advancing (similar to [[OPA]] insertion)
#*Insert laterally 45 degrees against tongue, advance and rotate to midline
#Inflate cuff (if applicable)
#Confirm placement as with endotracheal tube

===Intubating LMA<ref>https://calsprogram.org/manual/volume2/Section5_AirwaySkills/09-AirSk8IntubLarynMaskAirway13.html</ref>===
#Prepare patient as for intubation
#Partially deflate the cuff of the iLMA and lubricate
#Holding iLMA by metal handle only, insert into patient's mouth with the posterior surface of the iLMA against the hard palate
#Advance the iLMA until it is seated
#Inflate the iLMA cuff
#Ventilate patient and confirm placement as usual
#Lubricate endotracheal tube
#Insert ETT into the aperture on the iLMA
#Slide ETT to appropriate depth
#Inflate ETT cuff and confirm placement as usual
#Disconnect adaptor from ETT
#Deflate iLMA cuff
#Use obturator to push against ETT while slowly removing iLMA
#Grasp ETT in the oral cavity as soon as able
#When iLMA is fully removed, reattach ETT adaptor
#Ventilate patient and confirm placement as usual

==Complications<ref name="Anesthesia" />==
*Bronchospasm
*Hoarseness
*Laryngeal nerve injury
*Hypoglossal nerve injury
*Pharyngeal edema
*Dysphagia

==Special Considerations==
*There are 2 generations of supraglottic airway devices<ref>Timmermann, A. Supraglottic airways in difficult airway management: successes, failures, use and misuse. Anaesthesia, 2011,
66(Suppl. 2), pages 45–56.</ref><ref name="NAP4" />
**1st Gen = classic LMA, other standard LMAs
**2nd Gen = iGel, LMA Supreme, Pro-Seal LMA (PLMA)
*Second generation devices achieve improved esophageal and pharyngeal seal (causes ↑ oropharyngeal leak pressure), incorporate a "drain tube" that allows access to the esophagus and stomach, and usually have an incorporated bite block.
*Oropharyngeal leak pressure = the applied pressure at which the seal between the device and the larynx begins to leak.
**Peak inspiratory pressure needs to be less than the oropharyngeal leak pressure for effective ventilation and to prevent gastric insufflation.<ref name="LMA">Patel B., Bingham R. Laryngeal mask airway and other supraglottic airway devices in paediatric practice. Contin Educ Anaesth Crit Care Pain (2009) 9 (1): 6-9.</ref>
*Higher failure rate with obese patients, inappropriate patient position (e.g. trendelenberg), and placement by inexperienced provider<ref name="NAP4" />
*The AIRWAYS-2 trial found no significant difference in 30-day outcomes between initial use of SGAs and tracheal intubation during out-of-hospital cardiac arrest. However, it noted that SGAs had a higher initial ventilation success rate compared to tracheal intubation <ref> Benger JR, et al. Supraglottic airway device versus tracheal intubation in the initial airway management of out-of-hospital cardiac arrest: the AIRWAYS-2 cluster RCT. Health Technol Assess. 2022;26(21):1-158. doi:10.3310/VHOH9034 </ref>

==See Also==
{{Related Difficult Airway Pages}}

==External Links==
*[https://www.merckmanuals.com/professional/critical-care-medicine/how-to-do-other-airway-procedures/how-to-insert-a-laryngeal-mask-airway?query=supraglottic%20airway Merk Manual - How To Insert a Laryngeal Mask Airway]
*[https://www.merckmanuals.com/professional/critical-care-medicine/how-to-do-other-airway-procedures/how-to-insert-an-esophageal-tracheal-double-lumen-tube-combitube-or-a-king-laryngeal-tube?query=supraglottic%20airway Merk Manual - How To Insert an Esophageal-Tracheal Double Lumen Tube (Combitube®) or a King Laryngeal Tube] 

===Videos===
*Laryngeal Mask Airway (https://www.youtube.com/watch?v=-oXa-f5qkGY)
*I-Gel (https://www.youtube.com/watch?v=YuG6k6ndBpM)
*King Airway (https://www.youtube.com/watch?v=yJGuxDny_fo)

==References==
<references/>

[[Category:Critical Care]]
[[Category:Procedures]]