Endotracheal intubation can be difficult in the emergent situation, and it is important to have an appropriate backup strategy. Supraglottic airway devices have provided an alternative method for pediatric airway management that is relatively easy to learn, with a high success rate. This issue reviews the use of supraglottic airway devices in pediatric patients including common devices, indications and techniques for placement, and complications associated with their use. The use of supraglottic airway devices in the patient with a difficult airway is also discussed.
You are working in the ED when EMS arrives with a 4-year-old boy who is in respiratory distress. The paramedics report that the boy was seen earlier at an urgent care center and was diagnosed with influenza A by point-of-care testing. On examination, you note a visibly smaller mandible and a tongue set farther back than its typical position. His mother confirms that the boy has Pierre Robin sequence. As the patient is placed on a stretcher, you note that he is tired appearing, with significant nasal congestion and micrognathia. His vital signs are notable for a fever of 39.6°C (103.3°F), respiratory rate of 14 breaths/min, and oxygen saturation of 88% on room air. You are concerned about securing his airway, given his facial anomalies. What equipment should be kept at the bedside in case this progresses to respiratory failure? Is there a backup airway device that should be readily available? Should an advanced airway team be called?
During your next shift in the ED, you are caring for a 15-year-old boy with a traumatic elbow dislocation that occurred while he was playing soccer. The orthopedic surgeon on call would like to reduce the dislocation in the ED using procedural sedation. The patient recovered from an upper respiratory tract infection a couple of days ago, and you are concerned about possible airway complications. Does the recent upper respiratory tract infection increase the risk for possible airway compromise? Should this procedure be attempted without sedation?
While you are signing your note from the previous case, another patient arrives in the ED. It is a 5-month-old girl who is brought in by her mother after an episode of cyanosis at home. The girl has a history of congenital heart disease and a Blalock–Taussig shunt. Although the infant’s initial vital signs are initially reassuring, she quickly becomes limp and pale. On re-evaluation you note a heart rate in the 50s, with poor peripheral perfusion. Your team initiates cardiopulmonary resuscitation, and you prepare to secure her airway. You have limited experience with infants this age and must decide between endotracheal intubation or use of a supraglottic airway device. In a patient this age, would placing a supraglottic airway device be easier or could insertion be more complicated than in an older child?
Supraglottic airways are a group of airway devices used to secure a patient’s airway or as an aid to facilitate endotracheal intubation (ETI). The term supraglottic indicates that these devices sit just above the larynx and allow for oxygenation and ventilation. These devices are sometimes referred to as “extraglottic” instead of “supraglottic.” For the purposes of this article, these devices will be referred to as supraglottic airway devices (SGAs).
Airway management in the ED can be indicated for respiratory arrest or failure, inability to maintain the airway due to altered level of consciousness, or for procedures and diagnostic studies. ETI can be difficult in the emergent situation, and having an appropriate backup strategy is important. In many situations, SGAs can be used instead of ETI to manage a patient’s airway. Since oxygenation and ventilation can be provided through an SGA without the need for ETI, these devices provide a quick and safe method for managing difficult airways in pediatric patients in the ED.
SGAs are useful in the management of the difficult airway. They have been used in this capacity in the operating room, prehospital setting, and emergency department setting. Guidelines for management of a difficult airway in both adult and pediatric patients now commonly incorporate the use of SGAs into their suggested recommended workflow.1-3 In 1991, Benumof described the usefulness of SGAs in the “can’t intubate, can’t ventilate” scenario.4 Use of these devices to restore and maintain ventilation and oxygenation in adults, children, and infants with difficult airways has been published for many years.5-11 One study described a 94% success rate in providing rescue ventilation with SGAs in adults with unexpected difficult intubation and difficult bag-valve mask ventilation.12 A variety of SGAs are available to aid in performance of a difficult tracheal intubation. In several studies, fiberoptic intubation was significantly more successful on first attempt when using an intubating laryngeal mask airway (LMA).13,14 One example is the air-Q® intubating laryngeal airway used as a conduit for intubation in the pediatric patient with a difficult airway.15,16
This issue of Pediatric Emergency Medicine Practice reviews the history of SGAs, discusses types of devices that are commonly used in pediatric patients, and provides evidence-based recommendations for their use.
A literature search was performed in PubMed using the following search terms (and their combinations): pediatrics, children, anesthesia, pre-hospital, supraglottic, extraglottic, airway, emergency, intubation, laryngeal mask airway, LMA, combitube, iGel, SLIPA, Streamlined Liner of the Pharynx Airway, King Airway, and baska. Additionally, the bibliographies of articles were reviewed for other relevant publications. A search of the Cochrane Database of Systematic Reviews using the term supraglottic yielded 3 published articles. The first article compared SGAs and ETI in obese patients undergoing general anesthesia.17 The second compared 2 types of devices (LMA® ClassicTM [cLMA] and ProSeal™) for positive pressure ventilation in adults undergoing elective surgery.18 The third compared tracheal intubation with a flexible scope and other intubation techniques in obese patients undergoing general anesthesia.19 A total of 382 articles were reviewed, and 137 were chosen for inclusion. The evidence is backed by several high-quality studies, 7 practice guidelines, 16 randomized controlled trials, and 17 meta-analyses/systematic reviews. Due to a general paucity of pediatric literature on SGAs, much of the review led to adult-based scientific publications; many were included and applied to the pediatric population.
The pharyngeal bulb gasway was the first SGA. It was developed in the late 1930s by Beverley Charles Leech, who designed a device that would conform to the average adult pharynx, forming an airtight seal and allowing for the passage of gases through its core.20 This product fell out of favor with advancements in ETI.
Archie Brain introduced the next SGA in 1983. He noted that better gas exchange could be accomplished with an end-to-end connection at the perimeter of the larynx instead of the tube-in-a-tube method used with an endotracheal tube (ETT). This was accomplished via an elliptical cuff at the distal end of the SGA, which creates an airtight seal at the perimeter of the larynx when inflated.21,22 Initially available only in the United Kingdom, it quickly began being used in the United States, Australia, and Japan. The laryngeal mask was originally limited for use in patients who were under anesthesia but breathing spontaneously. Since then, the use of these devices has expanded to include use with controlled ventilation during operative procedures and as rescue devices.23,24 The LMA is produced by LMA® North America, Inc, and the term laryngeal mask is used generally for products made by any other manufacturer.25
The LMA was first approved by the United States Food and Drug Administration in 1991, and it has been adopted as one of the standard methods for providing oxygenation and ventilation in the operating room.26 Increased use has led to the development of a newer, “second generation” of SGAs. Pediatric anesthesiologists use SGAs in various situations, and they have adopted SGAs as a primary airway in children with difficult airways who are undergoing elective procedures.27 The use of SGAs during head and neck procedures is quite frequent; a survey by Patel and colleagues found that many pediatric anesthesiologists were comfortable using an SGA in situations that are considered more complicated, including laparoscopic surgery and in patients placed in the prone position.28 Although there is a theoretical risk that the SGA could be more easily dislodged while lying the patient prone, the literature supports use in this position.29,30
It has been noted that the smaller pediatric LMAs (sizes 1-2.5) can be more likely to partially block the glottic opening than larger models, due to malpositioning.31 When using smaller sizes, remember that these SGAs may require more frequent repositioning.
SGAs are often used in adult patients in cardiac arrest. SGAs can be placed quickly without interruption of cardiopulmonary resuscitation efforts, and they have been shown to provide similar oxygenation and ventilation in these situations when compared to ETI.32,33 The ability to intubate through some models also makes them an important component of any backup airway situation.
To view a video featuring Dr. Rich Levitan of Continulus.com reviewing types of SGAs and demonstrating insertion techniques from 4 different angles, see the video below:
For the complete Emergency Airway Masterclass with Rich Levitan from Continulus, go to Command the Airway with Rich Levitan. EB Medicine subscribers get 15% off! Use promo code EBM-15.
1. “The child did not have difficult airway features, so I did not have a backup airway ready.”
One study found that 20% of difficult airways in children were unanticipated.89 This contrasts the belief that pediatric difficult airway cases should be predictable. Clinicians should prepare to manage a difficult airway, regardless of the lack history or physical examination indicators.
2. “I did not know the child’s weight, so I chose the SGA size equivalent to the blade size.”
SGA sizing does not correlate with blade size or ETT size. When a patient’s weight is not known, a suitable LMA size can be determined using the combined width of the patient’s second, third, and fourth digits.46 The Broselow-Luten resuscitation tape, if available, contains LMA sizing and can be used to choose the correct LMA based on the patient’s height. There are other weight estimation formulas that do not require Broselow-Luten tape.
10. “The patient arrived with an SGA in place, so I removed it to place an ETT.”
Although SGAs have a greater risk of dislodgement than an ETT, it would not be prudent to remove a working advanced airway in an emergent situation. If the SGA has intubating capacity, an ETT may be placed somewhat easily. Alternatively, if the SGA is large enough to pass a bougie, it is possible to change it to an ETT using a Seldinger-like technique. Regardless, if physiologic parameters (pulse oximetry, waveform capnography) are within an acceptable range with an SGA in place, the patient should be stabilized prior to removing or replacing the SGA.
Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.
To help the reader judge the strength of each reference, pertinent information about the study, such as the type of study and the number of patients in the study is included in bold type following the references, where available. The most informative references cited in this paper, as determined by the authors, are noted by an asterisk (*) next to the number of the reference.
The Modified Mallampati Classification stratifies predicted difficulty of endotracheal intubation based on anatomic features.
The modified Mallampati classification predicts difficult airway in patients requiring endotracheal intubation. The tool is simple to use at the bedside, can be performed in < 1 minute, and has good accuracy (area under the summary receiver operating characteristic curve, 0.83) at predicting difficult airway (eg, difficult laryngoscopy, difficult intubation, or difficult ventilation). (Lee 2006)
The original Mallampati classification had 3 classes of visualization, but a fourth was added later by Samsoon and Young (1987) and shown to have greater predictive value. The latter version of the classification is most commonly used today. While the modified Mallampati classification is usually determined with the patient sitting up, a prospective cohort study suggested that evaluating the patient supine may better predict difficult intubation (area under the receiver operating characteristic curve, 0.82 supine vs 0.7 while sitting) (Hanouz 2018). A class 0 has been proposed by Ezri et al (1998) to denote “extremely easy” intubation, but evidence supporting its accuracy is limited to case reports. A low score may predict easy laryngoscopy and intubation, but does not guarantee it. While a high score should prompt caution, a low score is not intended to provide reassurance.
Consider strategies to improve ease of intubation in patients with a predicted difficult airway (class III-IV) (eg, video-assisted laryngoscopy, awake intubation). For patients with identified or anticipated difficult airways, consider involving other airway specialists early and identify alternatives to endotracheal intubation such as laryngeal mask airway, bougie-guided intubation, or other adjuncts. Before starting the procedure in any intubation, especially in an emergency setting, determine the “plan B” and “plan C” to be followed if initial attempts fail.
Derek Tam, MD, MPH
Christopher Tainter, MD, RDMS
The Mallampati score was initially developed for the operating room setting. Multiple large studies involving tens of thousands of patients have shown a reliable association between a higher Mallampati score (class III or IV) and difficult laryngoscopy and intubation.
Despite this, the Mallampati score does have its detractors. In a 2019 paper, Green and Roback argued that despite the high association seen with higher Mallampati class and difficult intubation, the sensitivity of the score is rather low, which is suboptimal for a screening test. They advocated for the use of the Mallampati score in the context of the total clinical picture. Furthermore, in the emergency setting, a patient with a failing airway or respiratory effort requiring intubation will still require intubation, regardless of the Mallampati score. Although a higher Mallampati score may prompt an earlier call to anesthesia or other specialties for assistance, its application in the emergent setting (emergency department, intensive care unit) may be limited, as the score was initially developed and has primarily been validated in the operating room setting.
To use the modified Mallampati classification, position the patient seated upright and direct the patient to open mouth and protrude tongue fully.
Seshagiri R. Mallampati, MD
Jennifer E. Sanders, MD, FAAP; Louis A. Spina, MD, FAAP
Heather M. Kuntz, MD, FACEP, FAAP; Shira A. Schlesinger, MD, MPH, FACEP
October 2, 2020
November 2, 2023
4 AMA PRA Category 1 Credits™, 4 ACEP Category I Credits, 4 AAP Prescribed Credits, 4 AOA Category 2-A or 2-B Credits.
Date of Original Release: October 1, 2020. Date of most recent review: September 15, 2020. Termination date: October 1, 2023.
Accreditation: EB Medicine is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians. This activity has been planned and implemented in accordance with the accreditation requirements and policies of the ACCME.
Credit Designation: EB Medicine designates this enduring material for a maximum of 4 AMA PRA Category 1 CreditsTM. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
Specialty CME: Not applicable. For more information, please call Customer Service at 1-800-249-5770.
ACEP Accreditation: Pediatric Emergency Medicine Practice is also approved by the American College of Emergency Physicians for 48 hours of ACEP Category I credit per annual subscription.
AAP Accreditation: This continuing medical education activity has been reviewed by the American Academy of Pediatrics and is acceptable for a maximum of 48 AAP credits per year. These credits can be applied toward the AAP CME/CPD Award available to Fellows and Candidate Fellows of the American Academy of Pediatrics.
AOA Accreditation: Pediatric Emergency Medicine Practice is eligible for up to 48 American Osteopathic Association Category 2-A or 2-B credit hours per year.
Needs Assessment: The need for this educational activity was determined by a survey of medical staff, including the editorial board of this publication; review of morbidity and mortality data from the CDC, AHA, NCHS, and ACEP; and evaluation of prior activities for emergency physicians.
Target Audience: This enduring material is designed for emergency medicine physicians, physician assistants, nurse practitioners, and residents.
Goals: Upon completion of this activity, you should be able to: (1) demonstrate medical decision-making based on the strongest clinical evidence; (2) cost-effectively diagnose and treat the most critical ED presentations; and (3) describe the most common medicolegal pitfalls for each topic covered.
Discussion of Investigational Information: As part of the journal, faculty may be presenting investigational information about pharmaceutical products that is outside Food and Drug Administration approved labeling. Information presented as part of this activity is intended solely as continuing medical education and is not intended to promote off-label use of any pharmaceutical product.
Faculty Disclosures: It is the policy of EB Medicine to ensure objectivity, balance, independence, transparency, and scientific rigor in all CME-sponsored educational activities. All faculty participating in the planning or implementation of a sponsored activity are expected to disclose to the audience any relevant financial relationships and to assist in resolving any conflict of interest that may arise from the relationship. Presenters must also make a meaningful disclosure to the audience of their discussions of unlabeled or unapproved drugs or devices. In compliance with all ACCME Essentials, Standards, and Guidelines, all faculty for this CME activity were asked to complete a full disclosure statement. The information received is as follows: Dr. Sanders, Dr. Spina, Dr. Kuntz, Dr. Schlesinger, Dr. Mishler, Dr. Claudius, Dr. Horeczko, and their related parties report no significant financial interest or other relationship with the manufacturer(s) of any commercial product(s) discussed in this educational presentation.
Commercial Support: This issue of Pediatric Emergency Medicine Practice did not receive any commercial support.
Earning Credit: Two Convenient Methods: (1) Go online to www.ebmedicine.net/CME and click on the title of this article. (2) Mail or fax the CME Answer And Evaluation Form with your June and December issues to Pediatric Emergency Medicine Practice.
Hardware/Software Requirements: You will need a Macintosh or PC with internet capabilities to access the website.
Additional Policies: For additional policies, including our statement of conflict of interest, source of funding, statement of informed consent, and statement of human and animal rights, visit https://www.ebmedicine.net/policies.