








































Anesthesia eJournal
Volume 3 Issue 1 2015

AEJ

Educated Hand Publishing LLC 
“The Science Behind the Art”  

 Anesthesia eJournal - Online
ISSN 2333-2611

The Laryngeal Mask Airway: Is It Safe for Pediatric Adenotonsillectomy?
Jo Reid, CRNA, MSNA
Paul N. Austin, CRNA, PhD**
Ricardo E. Rodriguez, PhD***

Source of grant or financial support: None
Disclosure: The author has no commercial associations that might pose a conflict of interest in connection with this work.

Abstract
Tonsillectomy with or without adenoidectomy (T&A) is one of the most common pediatric surgical procedures 
performed in the United States. Traditionally, an endotracheal tube has been used to secure the airway in these cases. 
However, the laryngeal mask airway (LMA) is also used for pediatric T&As. This review explores the question, In 
pediatric patients undergoing tonsillectomy with or without adenoidectomy, does the laryngeal mask airway compared 
with the endotracheal tube provide a safe and effective means of airway management? While all evidence sources 
concluded that it was possible to use an LMA for pediatric T&A, not all investigators fully supported its use in this 
setting. The authors of 6 of the 7 evidence sources determined that the LMA was an overall safe and viable alternative for 
this procedure, but one of the randomized controlled trials identified issues with kinking and visualization and called for 
further study. Future investigation should compare different types of laryngeal mask airways to determine superiority in 
terms of surgical access, visualization, and reduced displacement or kinking with insertion of the mouth gag.

KEYWORDS: Adenotonsillectomy, anesthesia, laryngeal mask airway, pediatrics, tonsillectomy.

INTRODUCTION
About 500,000 tonsillectomies with or without adenoidectomy 

are performed in children younger than 15 years each year in 
the United States.1 For the anesthesia provider, a secure and 
protected airway is one of the primary goals during this procedure 
due to sharing the airway with the surgeon. Traditionally, the 
endotracheal tube (ETT) has been the airway of choice for 
pediatric patients undergoing adenotonsillectomy (T&A), but 
it is not without potential complications. These include, but 
are not limited to, trauma to the lips, teeth, gums, and larynx; 
bronchospasm; and laryngospasm. Laryngospasm, occurring in 
4% to 14% of pediatric patients undergoing general anesthesia, is 
a potentially life-threatening complication that can occur during 
induction or emergence from anesthesia.2

The laryngeal mask airway (LMA) was developed by Dr. Archie 
Brain, introduced to the practice of anesthesia in 1988, and 
approved by the U.S. Food and Drug Administration in 1991.3 Its 
popularity within the anesthesia community continues to grow, 
and its use has been reported for otolaryngoscopy procedures.4 
This paper reviews the evidence comparing the efficacy of the 
LMA to the ETT in pediatric patients undergoing tonsillectomy 
or T&A.

HISTORY AND REVIEW OF THE 
LITERATURE 
History. Tonsillectomy with or without adenoidectomy 

(collectively referred to as “T&A”) is a common pediatric 
surgical procedure in the United States.1 Reasons that children 
are scheduled for a T&A are chronic or recurrent tonsillitis, 
obstructive sleep apnea, and obstructive tonsillar hyperplasia. 
Upper respiratory infections are also a common comorbidity in 
this patient population. For these reasons, patients who present 
for this surgical procedure are at increased risk for airway 
complications.1

The LMA is a supraglottic airway device inserted into the 
patient’s hypopharynx, where it rests above the laryngeal 
inlet. Advantages to using the LMA include ease of insertion, 
decreased respiratory stimulation, decreased risk of trauma 
(particularly to the larynx), and avoidance of the use of 
neuromuscular blocking agents.2 The use of the LMA for T&As 
is not without potential complications, with 2 of the most 
common being mechanical obstruction with placement of the 
mouth gag by the surgeon and surgical access. The surgeon’s 
training and preference and the experience level of the anesthesia 
provider are important factors that should not be over-looked. 



Anesthesia eJournal                         www.anesthesiaejournal.com
Volume 3 Issue 1 2015 

A review of the literature examining patient outcomes and 
satisfaction of all involved may lead to a change in care for this 
patient population.

The PICO Question
The key to any successful search for evidence begins with the 

development of a well-focused clinical question. The patient, 
intervention, comparison, and outcome (PICO) design helps 
facilitate this search for evidence.5 The PICO question guiding 
the literature search was “In pediatric patients undergoing T&A 
(patient), does the LMA (intervention) compared with an 
ETT (comparison) provide a safe and effective means of airway 
management (outcome)?”

Search Strategy 
The search for evidence was conducted using the following 

databases: PubMed (1990-2014), National Guideline 
Clearinghouse (1990-2014), and the Cochrane Library (1990-
2014). Keywords and keyword strings used for the search 
included “pediatric(s),” “laryngeal mask airway,” “LMA,” 
“endotracheal tube,” “T&A,” “ tonsillectomy,” “adenoidectomy,” 
“adenotonsillectomy,” and “complications,” alone or in 
combination.
The search for evidence was limited to systematic reviews 

with and without meta analysis, interventional studies, and 
observational studies. English language peer reviewed journal 
articles and evidence based clinical practice guidelines from 
professional organizations and governmental websites comparing 
the use of LMA with ETT for pediatric T&A were included. 
Evidence comparing the use of LMAs with ETTs in adults was 
excluded. 
The title of each evidence source was reviewed to determine if 

inclusion criteria were met. The abstract was reviewed and the 
full text examined. The reference lists from included articles were 
searched for additional evidence. Surgical colleagues of the one 
of the authors ( JR) were interviewed for potential sources of 
evidence. Any sources received from these experts went through 
the same steps to determine if inclusion criteria were met. 
Records were maintained for these sources after each level of 
review. Studies included in an appraised systematic review were 
not appraised.
Critical Appraisal of the Literature
Seven citations4,6-11 met the search criteria (Figure 1). Critical 

appraisal of the evidence followed the methods outlined by 
Melnyk and Fineout-Overholt.12 Table 1 contains the evaluations 
of five randomized controlled trials (RCTs),4,6-9 a retrospective 
review11 comparing the use of LMA to the ETT for pediatric 
T&A, and a prospective study10 examining the safety of the LMA 
for pediatric T&A.
Authors of all the RCTs4,6-9 randomly assigned subjects 

undergoing T&A using LMA or an ETT. All but 1 trial6 used 
power analysis to determine sample size. Due to the nature of 
the trials, blinding of the anesthesia provider and surgeon was 
not possible. Only 1 trial6 out of the 5 RCTs in this literature 
review had the advantage of being a blinded study. Postanesthesia 
providers and the phone surveyor who called the subjects 24 
hours after surgery were blinded. This was also the only study that 

lost a subject to follow up, because phone surveyors were unable 
to reach that subject by phone. No mention of the data collectors’ 
level of training was provided for any RCT.4,6-9

There were no statistically significant demographic differences 
between the LMA group and the ETT group in any RCT.4,6-9  

The only difference between the experimental and control group 
in each of these trials was the device used for airway management. 
All RCTs4,6-9 sought to determine the suitability of the LMA 
for T&A. Three RCTs4,6,7 involved anesthesia providers who had 
undergone additional pediatric training, and the other 28,9 did 
not mention extra pediatric training. In an RCT,9 4 anesthetists 
participated and were experienced in pediatric intubation, but 
they had no experience with the LMA for T&As until the start 
of the study. The anesthesia providers involved in another RCT8 
spent a year before the start of the trial familiarizing anesthesia 
providers with the reinforced LMA.
The setting of the nonrandomized prospective study10 was 

an office-based otolaryngology practice in Norway. Data were 
collected from 1,126 consecutive patients over a 5-year period. 
The authors examined whether the LMA was safe for T&A and 
if this procedure could be safely carried out in an office based 
practice. Subjects scheduled for adenoidectomy were 2 years old 
and older, while subjects scheduled for tonsillectomy were 3 years 
and older. The same surgical team was used for all procedures and 
consisted of a surgeon, anesthesiologist, nurse anesthetist, and 
nurse assistant. A reusable LMA was chosen for all patients. Data 
collection methods were not described in detail. All tonsillectomy 
patients were called 24 hours after surgery to identify problems 
such as sore throat. 
Lalwani et al11 reported the findings of a retrospective review 

conducted at a children’s hospital in Oregon. Data were collected 
from the electronic health records of more than 1,000 subjects 
who underwent T&A  from January 2002 to December 2006. 
Three pediatric otolaryngology surgeons and 15 pediatric 
anesthesiologists were involved in the cases, and subjects were 
grouped according to method of airway control. 

DISCUSSION OF STATE OF THE ART
The authors of 44,6,8,9 of the 54,6-9 RCTs concluded that the LMA 

was a viable and overall safe alternative to the ETT for pediatric 
T&A. However, 1 group4 indicated that visualization and kinking 
issues should be addressed. The RCT by Ranieri et al7 concluded 
that the ETT was preferred over the LMA for safety. 
In an RCT, Sierpina et al6 used a reinforced LMA for 

pediatric T&A. Thirty-six variables were analyzed, including 
safety, comfort, complications, and postoperative problems. 
Less coughing and gagging were reported with the LMA, 
and no statistically significant differences in rate of respiratory 
complications were reported between the 2 groups. None of 
the subjects in the LMA group required conversion to an ETT, 
but all anesthetics and surgical procedures were performed by 
providers with specialty training in the field of pediatrics. This 
may affect the results in settings where specialty trained providers 
are not available. There was no significant difference in operative 
times between the 2 groups. While the authors did not state that 
the LMA was as safe as the ETT, it is their airway of choice in 
healthy, nonobese children without severe obstructive sleep apnea 
presenting for T&A.6



Anesthesia eJournal                         www.anesthesiaejournal.com
Volume 3 Issue 1 2015 

The remaining 3 studies4,8,9 also determined that the LMA 
was an effective alternative for airway management for pediatric 
T&A. The anesthesia providers involved in 1 RCT4 had received 
extra anesthesia training. One of the studies4 used flexible LMAs, 
and 28,9 used reinforced LMAs. In the study4 examining use of 
the flexible LMA, there was kinking of the LMA in 15 subjects 
with insertion of the mouth gag in the study using the flexible 
LMA, with 8 requiring conversion to an ETT. Two additional 
subjects required conversion to an ETT due to poor visualization. 
There were no significant differences in the postoperative rate of 
laryngospasm or desaturation between the 2 groups.
 Both RCTs8,9 using a reinforced LMA described 5 subjects 

requiring conversion to an ETT. Doksrød et al9 reported that 
all 5 conversions were due to poor surgical access. In the other 
RCT,8 4 of the conversions were due to transient drops in oxygen 
saturation, and 1 was due to an unresolved leak with positive 
pressure ventilation in a subject with very large tonsils. The 
authors8 pointed out that all 5 conversions occurred in the first 
15 cases of the study. After it was discovered that a deeper plane 
of anesthesia was necessary before insertion of the LMA, no 
other subjects required conversion to an ETT. The occurrence 
of postoperative laryngospasm and desaturation were the same 
between the ETT and LMA groups.8

The investigators7 of the fifth RCT analyzed concluded that 
the disposable LMA could be used, but the ETT was preferred 
for safety. They pointed out a greater incidence of desaturation 
due to unresolved leaks in the LMA group after establishment 
of the surgical field. Eight subjects in the LMA group developed 
a leak after hyperextension of the neck, which was unresolved 
after repositioning the LMA. One subject in the LMA group 
regurgitated and required conversion to an ETT. There were 
no significant differences in the operative time or rate of 
laryngospasm between the 2 groups. 
The prospective study10 provided a lower quality of evidence. 

A reusable LMA was used for all subjects unless a complication 
arose. Six subjects required repositioning of the LMA before the 
start of surgery, and conversion to ETT was required in 7 cases. 
It was not reported if repositioning was needed before or after 
insertion of the mouth gag. Six of the subjects who required 
conversion to an ETT had an air leak around the LMA, which 
may have been the result of using a flexible, reusable LMA. One 
subject required intubation at the end of surgery due to atelectasis 
from a bronchial plug. There was no discussion of how the sample 
size was determined or why a flexible LMA was chosen. Neither 
was there any discussion of the age of the subjects who required 
conversion to an ETT.
The retrospective review11 also provided a lower quality of 

evidence. There were no statistically significant demographic 
differences among the LMA success, LMA failure, and ETT 

groups. The investigators identified predictors of failure and 
complications with the LMA and concluded that an LMA was 
an alternative technique for T&A. Of 1,162 subjects (LMA 
37.6%, flexible LMA 2.7%, ETT 59.7% ), the LMA failed 33 
times, with almost 80% of the failures occurring during induction 
or insertion of the mouth gag. Age, type of surgery, mode of 
ventilation, and surgeon were associated with LMA failure. It is 
important to note that 1 surgeon and adenoidectomy alone had a 
statistically significant lower rate of failure, whereas the younger 
age of the  subject and the use of controlled ventilation were 
associated with a statistically significant higher rate of failure. 
Self-report bias and lack of randomization were limitations of 
this retrospective review. It was impossible to determine if the 
experience level of the anesthesiologist affected outcomes, due to 
the low number of subjects per anesthesia provider. 

SUMMARY
While all evidence4,6-11 showed that it is possible to use an LMA 

for pediatric T&A, all investigators did not fully support its use 
in this setting. The authors of 6 of the evidence sources4,6,8,9,-11 
determined that the LMA was an overall safe and viable 
alternative for pediatric T&A, but 1 group4 indicated that the 
issues with kinking and visualization needed further study. Only 1 
source7 concluded that the ETT was preferred over the disposable 
LMA for safety. The retrospective review11 indicated that the 
LMA is an alternative to an ETT for T&A.
The reinforced LMA was used in 3 of the trials6,8,9 supporting 

the use of the LMA, and the flexible LMA was used in the 2 
trials4,7 reporting issues with kinking and other complications. 
Although the investigators of a large study10 successfully used a 
non-reinforced LMA, they concluded that the type of LMA used 
could have been responsible for its failure. Age may also play a 
role in failure of the LMA. Lalwani et al11 reported that, as age 
decreased, the rate of failure increased. It should be noted that the 
flexible LMA was used in all subjects in this review. 
Anesthesia providers must choose the airway management 

method in conjunction with the surgeon and consider the risks 
and benefits of each device. To increase safety, it is important 
that the anesthesia provider has experience using the LMA in 
the pediatric population. The cooperation of the surgeon is also 
necessary, because adjustment of the LMA or mouth gag may be 
necessary. 
Future research should compare the reinforced LMA with the 

flexible LMA to determine if it provides better surgical access, 
visualization, and reduced kinking or displacement (or both) on 
insertion of the mouth gag. Because a benefit of using the LMA 
is decreased respiratory stimulation, the inclusion of subjects 
with asthma or recent upper respiratory infections should also be 
considered. 



Anesthesia eJournal                         www.anesthesiaejournal.com
Volume 3 Issue 1 2015 

 
REFERENCES

1. Tonsillectomy and/or adenoidectomy in children: preoperative and intraoperative care. UpToDate. Available at: http://www.
uptodate.com/contents/tonsillectomy-and-or-adenoidectomy-in-children-preoperative-and-intraoperative-care. Accessed 
April 19, 2015.

2. Flick RP, Wilder RT, Pieper SF, et al. Risk factors for laryngospasm in children during general anesthesia. Paediatr Anaesth. 
2008;18(4):289-296.

3. Hernandez MR, Klock PA Jr, Ovassapian A. Evolution of the extraglottic airway: a review of its history, applications, and 
practical tips for success. Anesth Analg. 2012;114(2):349-368.

4. Peng A, Dodson KM, Thacker LR, Kierce J, Shapiro J, Baldassari CM. Use of laryngeal mask airway in pediatric 
adenotonsillectomy. Arch Otolaryngol Head Neck Surg. 2011;137(1):42-46. 

5. Richardson WS, Wilson MC, Nishikawa J, Hayward RS. The well-built clinical question: a key to evidence-based practices. 
ACP J Club. 1995;123(3):A12-A13.

6. Sierpina DI, Chaudhary H, Walner DL, et al. Laryngeal mask airway versus endotracheal tube in pediatric adenotonsillectomy. 
Laryngoscope. 2012;122(2):429-435.

7. Ranieri D Jr., Neubauer AG, Ranieri DM, do Nascimento P Jr. The use of disposable laryngeal mask airway for 
adenotonsillectomies. Rev Bras Anestesiol. 2012;62(6):788-797.

8. Doksrød S, Løfgren B, Nordhammer A, Svendsen MV, Gisselsson L, Raeder J. Reinforced laryngeal mask airway compared 
with endotracheal tube for adenotonsillectomies. Eur J Anaesthesiol. 2010;27(11):941-946.

9. Webster AC, Morley-Foster PK, Dain S, et al. Anaesthesia for adenotonsillectomy: a comparison between tracheal intubation 
and the armoured laryngeal mask airway. Can J Anaesth. 1993;40(12):1171-1177.

10. Gravningsbråten R, Nicklasson B, Raeder J. Safety of laryngeal mask airway and short-stay practice in office-based 
adenotonsillectomy. Acta Anaesthesiol Scand. 2009;53(2):218-222.

11. Lalwani K, Richins S, Aliason I, Milczuk H, Fu R. The laryngeal mask airway for pediatric adenotonsillectomy: Predictors of 
failure and complications. Int J Pediatr Otorhino-laryngol. 2013;77(1):25-28.

12. Melnyk BM, Fineout-Overholt E. Evidence-Based Practice in Nursing and Healthcare: A Guide to Best Practice. 2nd ed. 
Philadelphia: Wolters Kluwer, Lippincott Williams & Wilkins. 2011:3-24.

Texas Wesleyan University
Graduate Programs of Nurse Anesthesia, Doctorate of 
Nurse Anesthesia Program
Fort Worth, TX

3081 Linksland Road
Mount Pleasant, SC 29466
Voice Phone number: 843-810-9910
Email: jreid4@hotmail.com

**Professor, Texas Wesleyan University, Graduate Programs 
of Nurse Anesthesia
14311 Harvest Moon Rd
Boyds, MD 20841
301-728-5435
paustin@txwes.edu

***Professor, Texas Wesleyan University, Graduate Programs 
of Nurse Anesthesia
1201 Wesleyan St
Fort Worth, TX 76106
817-531-4256
rrodriguez@txwes.edu

Short Biographical Statement

Jo Reid, CRNA, DNAP, is the chief cardiac nurse anesthetist at Trident Medical Center in Charleston, SC. The author 
was a student in the Doctorate of Nurse Anesthesia program at Texas Wesleyan University at the time this article was 
written.

Paul N. Austin, CRNA, PhD, is a professor, Doctorate of Nurse Anesthesia Practice program at Texas Wesleyan 
University.

Ricardo E. Rodriguez, PhD, is a professor of pharmacology, Graduate Programs of Nurse Anesthesia at Texas Wesleyan 
University.



Anesthesia eJournal                         www.anesthesiaejournal.com
Volume 3 Issue 1 2015 

 
Figure 1 —Evidence Comparing the Use of the Laryngeal Mask Airway to the Endotracheal Tube for Pediatric Adenotonsillectomy 

Table 1
Evidence Source Type and level of 

evidencea Sample size
LMA Type

Outcome Comments

Webster et al9

(1993)
Randomized 
clinical trial 
Level II
109
Reinforced

LMA inserted faster than ETT in 
91% of cases (P<.001)
HR and MAP less (P<.001) in 

LMA group

Sample size determined using a power 
analysis
5 subjects were converted to ETT 

early in the study when providers were 
unfamiliar with the LMA for T&A

Gravningsbråten et al10

(2009)
Prospective study
Level III

1,126

Reusable

Conversion from LMA to ETT 
occurred in 6 subjects (0.5%) due to 
leakage with ventilation
1 subject (0.1%) required 

intubation with lavage and suction 
due to a bronchial plug at the end 
of the operation

The same team performed all cases
No randomization; the LMA was the 

first choice for airway management

12 sources were found using the initial key 
word string “pediatric and laryngeal mask 
airway and tonsillectomy”

6 sources were found when the word 
“adenoidectomy” was substituted for 
“tonsillectomy”

3 sources were found when 
“adenotonsillectomy” was substituted for 
“adenoidectomy”

10 sources met the inclusion criteria based 
on title

8 sources met the inclusion criteria based on 
the abstract

7 sources met the inclusion criteria based on 
the full text

The results of these searches 
were found in the results of the 
initial keyword string



Anesthesia eJournal                         www.anesthesiaejournal.com
Volume 3 Issue 1 2015 

Doksrød et al8

(2010)
Randomized
Single center trial
Level II
134
Reinforced

5 LMA cases converted to ETT 
due to inferior surgical access 
Significantly less pain in LMA  

group (P=.015) during first 4 hours

Randomization based on computer 
generated program 
Case completion rate with LMA was 

92.8%
Faces/Pain Scale was used, and subjects/

parents were instructed in its use
Sample size based on 80% statistical 

power and a level of 5%
Peng et al4
(2011)

Randomized
clinical trial
Level II
134
Flexible

No statistically significant 
difference in rate of laryngospasm 
or adverse perioperative events 
No statistically significant 

difference in total anesthesia, 
surgical, or recovery times

Sample size determined using a power 
analysis
Data from 12 subjects in the LMA 

added to ETT, so did not follow intention 
to treat

Sierpina et al6

(2012)
Randomized
clinical trial
Level II
117
Flexible

Less coughing and gagging during 
anesthesia for all surgeries with 
LMA but no difference between 
the ETT tonsillectomies

Recovery nurses and phone surveyors 
were blinded 
No discussion of how sample size was 

determined

Ranieri et al7 
(2012)

Randomized
clinical trial
Level II
204
Disposable

No significant difference in 
respiratory complications 
4 subjects converted to ETT
Greater incidence of SaO2 

decreased in LMA after operative 
field established (P=<.001) 

Single surgical and anesthesia team
Specific definitions for each respiratory 

complication were provided 
LMA repositioned; if leak still present, 

converted to ETT to avoid hypoxemia or 
other complications
Limitations due to nature of study 

include lack of randomization and 
possible self-report bias

Lalwani et al11

(2013)
Retrospective
review
Level IV
1,199
Flexible (2.7%, of 

subjects)
LMA type not 

described (37.6% of 
sub-jects)
ETT (59.6%

Overall failure rate of the LMA 
was 6.8%
Adenoidectomy alone had lower 

odds of failure compared with 
tonsillectomy or T&A (OR 0.28, 
95% CI 0.15-0.52)
One surgeon associated with 

decreased odds of failure (OR 0.46, 
95% CI 0.45-0.48)
Younger subjects associated with 

increased odds of failure (OR 1.05 
for each year decrease in age, 95% 
CI 1.03-1.07)
Controlled ventilation associated 

with increased odds of failure (OR 
7.17, 95% CI 4.99-10.32)
Unable to compare outcomes 

between anesthesia providers due 
to inadequate number of cases per 
provider

Unable to compare outcomes between 
anesthesia providers due to inadequate 
number of cases per provider

aFrom Melnyk and Fineout-Overholt12

CI, confidence interval; ETT, endotracheal tube; HR, heart rate; LMA, laryngeal mask airway; MAP, mean arterial pressure; OR, 
odds ratio; T&A, adenotonsillectomy; SaO2, oxygen saturation of hemoglobin in arterial blood.


