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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_4421_Библиотеки_им_академика_М_И_Перельмана.pdf
15.10 Expected Outcomes by Population – 235
15.10.1 General Population – 235
15.10.2 Complex Children – 235
15.10.3 Hypopnea Versus Apnea Predominant – 236
15.11 Outcomes: QOL, Cognition, Behavior, Cardiovascular
Parameters – 236
15.11.1 Quality ofLife – 236
15.11.2 Cognition andBehavior – 236
15.11.3 Cardiovascular Parameters – 237
15.12 Comparison toConservative Management – 237
15.13 Conclusion – 238
References – 238
Surgical Management ofOSA: Adenotonsillectomy
227
15
15.1 Introduction: Background Information
Tonsillectomy with or without adenoidectomy (T&A) is
one of the most common pediatric surgical procedures
with over half a million procedures performed annually in the USA.Overall, the rate of T&A has nearly
doubled from 1996 to 2006, despite a sharp decline in
the procedure being performed for recurrent acute tonsillitis. This growth reects the increased awareness of
the morbidity of obstructive sleep apnea (OSA) in children and a resultant increase in T&A for this sleep disorder [1]. OSA prevalence is 6% in all children but 59%
in obese children [2]. Up to 20% of children have sleepdisordered breathing (SDB) [3] that is a clinical diagnosis
and includes a spectrum ranging from primary snoring
to OSA.OSA is characterized by recurrent obstruction
causing disruption in normal sleep architecture that
often leads to periods of hypoxemia and is diagnosed
with polysomnography (PSG). Adenotonsillar hypertrophy is the principal cause of SDB in children, and the
most common indication for T&A.
15.2 Tonsil andAdenoid Anatomy,
Physiology, Immunology, Purpose
Waldeyer’s ring refers to a ring of lymphoid tissue within
the pharynx including the lingual tonsils, palatine tonsils (tonsils), and pharyngeal tonsils (adenoids). The second branchial pouch forms the tonsil and its arches also
known as the “tonsillar pillars.” The anterior tonsillar
pillar consists of the palatoglossus muscle, while the posterior tonsillar pillar is the palatopharyngeus muscle. The
tonsils are located within the oropharynx just distal to the
junction of the hard and soft palate. The palatoglossus
(anterior pillar), palatopharyngeus muscles (posterior
pillar), and superior pharyngeal constrictor muscles lie
anterior, posterior, and lateral to the tonsil respectively.
The main arterial supply to the tonsil includes branches
from the facial, dorsal lingual, ascending pharyngeal,
ascending, and lesser palatine arteries. The arterial supply is primarily inferiorly along the lower pole. Nerve
supply is primarily from tonsillar branches of the glossopharyngeal nerve and the descending branch of the lesser
palatine nerve [4]. Non- keratizing squamous epithelium
lines a series of 10–30 mucosal invaginations forming
crypts, thus increasing the surface area of the tonsillar
epithelium. The tonsils function as a secondary lymphatic organ. Specialized “M” cells line the epithelium,
internalizing antigens and initiating a predominantly
antibody-driven B-cell adaptive immune response. The
level of the immunologic activity of the tonsil is typically
greatest between the ages of 3 and 10years, after which
time the tonsil begins to involute [5].
Two lateral primordia fuse together to form the
midline adenoid tissue which lies within the nasopharynx medial to the torus tubaris, superior to Passavant’s
ridge, and posterior to the choana and posterior nasal
septum. The main arterial supply includes pharyngeal
branches of the ascending pharyngeal, ascending palatine, and maxillary artery with small contribution from
the pterygoid canal and tonsillar branch of the facial
artery. The pharyngeal plexus supplies innervation.
The adenoid pad is lined with pseudostratied ciliated
columnar epithelium. Like the palatine tonsil, the epithelium is plicated to increase the surface area of the
epithelium. The adenoids are also a secondary lymphoid
organ whose immunologic function mirrors that of the
palatine tonsils [4].
15.3 OSA asanIndication for
Adenotonsillectomy: Guidelines
Clinical Practice Guidelines in 2019 by the American
Academy of Otolaryngology– Head and Neck Surgery
(AAO-HNS) recommend T&A for OSA [5]. SDB has detrimental, well-known, long-term effects on patient health
that include behavioral problems, diminished quality of
life, enuresis, growth impairment, and decreased school
performance. There is evidence for improvement in all
of these areas post-T&A and therefore the procedure is
recommended as the rst-line treatment in children with
adenotonsillar hypertrophy and SDB/OSA.
Clinical practice guidelines by the American
Academy of Pediatrics, revised in 2012, also recommend
T&A as the rst-line treatment in children with OSA
and adenotonsillar hypertrophy while CPAP should be
considered in those with OSA but without adenotonsillar hypertrophy or if surgical risks are signicant [6].
15.4 Preoperative Assessment
15.4.1 Physical Examination
Prior to proceeding with T&A, it is important to document tonsil size and perform a full head and neck examination. The most commonly utilized scale for assessing
the tonsil size is the Brodsky grading scale [7]. Tonsils
are given a grade of 1–4 with grade 0 denoting absence
of tonsils (. Fig.15.1). Tonsils encompassing ≤25% of
the oropharyngeal airway (lateral dimension) is given
a grade of 1, while tonsils occupying between 26–50%,
51–75%, and 76–100% of the oropharyngeal space are
of grades 2, 3, and 4 respectively. Tonsil grade is often
recorded as 1+, 2+, 3+, or 4+ instead of grade 1, 2, 3, or
4 and both should be considered synonymous.
228
A. G. Ordemann and R. B. Mitchell
. Fig. 15.1 Brodsky scale for grading tonsil hypertrophy [7]
15
The Friedman scale is the second most common
grading scale. Tonsils are given a grade of 0–4. Tonsils
not visible (often post-tonsillectomy) are given a grade
of 0. Tonsils within the tonsillar fossa are given a grade
of 1. Tonsils visible beyond the anterior pillars are
grade 2. Tonsils extending 75% of the way to midline
are grade 3. Completely obstructing (“kissing” tonsils)
are grade 4 [8]. Both grading systems are limited due to
the inability to account for endophytic tonsils that may
obstruct the oropharynx signicantly that is not visualized without endoscopy.
A recent study demonstrated higher mean intraobserver and interobserver reliability for the Brodsky grading scale than for the Friedman scale, 0.954 and 0.721
versus 0.932 and 0.647 respectively. The authors supported the adoption of the Brodsky scale for exclusive
use in clinical documentation to make future research
reporting uniform [9].
While tonsil size is important to record, its correlation with the apnea–hypopnea index (AHI), the principal
measure of OSA severity, is complex. In a 2011 systematic review of tonsil size and OSA severity as measured
by AHI, no correlation between tonsil size and OSA
severity was reported. Of the 20 studies included, only
four studies were high quality and all found no signicant correlation between tonsil size and AHI.Although
obese and syndromic children were excluded, there is no
reason to assume that tonsillar size and OSA severity
will correlate differently in these children [10].
In a 2015 retrospective case series of 70 patients with
baseline AHI≥ 5, Tang etal. showed that neither adenoid nor tonsil size correlated with OSA severity [11].
However, patients with larger Brodsky grade tonsils
were more likely to have a resolution of OSA following
T&A (AHI < 1). Overall resolution of OSA was seen
in 25%, 50%, and 36% of children with 2+, 3+, and 4+
tonsils, respectively. Signicant improvement in AHI
and hypopnea index was seen in all tonsil size groups,
while improvements in apnea index and oxygen saturation nadir were signicant only in the 3+ and 4+ groups.
Limitations included a lack of a large 1+ tonsil cohort
and a lack of objective measurements, such as volumetric analysis.
Unlike subjective grading methods, objective tonsil
size measures have been shown to correlate with OSA
severity. In a study by Howard and Brietzke, tonsil
weight (as measured postoperatively) was signicantly
correlated with preoperative AHI, but subjective adenoid size, tonsil size (Brodsky grade), Mallampati score,
or any of the pharyngeal measurements were not [12].
However, this is complicated by the fact that objective
measurements of tonsil volume and weight correlated
well with subjective tonsil measurements [12]. Thus
objective tonsil size is a better representation of airway
constriction particularly with endophytic tonsils, but
can generally only be done postoperatively.
For a more accurate measurement, some advocate
for endoscopic analysis of tonsil size. In 2017, Patel
et al. proposed a novel endoscopic tonsil grading system comprising measurements in the anterior-posterior
and medial-lateral dimensions performed in 50 patients
prospectively [13]. Grade 1 was given if tonsil occupied
0–25% of oropharyngeal width to midline or depth,
while 26–50%, 51–75%, and 76–100% correlated with
grade 2, 3, and 4. A grade number was given to both
dimensions and an average of the two was taken to
determine the nal grade. This system was compared to
the Brodsky scale, modied Brodsky scale (with tongue
depressor), and Parikh adenoid grading scale (reviewed
below). All scales had good interrater reliability: 0.83
for the modied Brodsky scale, 0.89 for the Brodsky
scale, 0.94 for the Parikh scale, and 0.98 for their newly
proposed endoscopic scale. They also studied the correlation of the different scales with quality of life, as measured by the obstructive sleep apnea-18 (OSA-18) and
the BMI.The OSA-18, a subjective quality of life (QOL)
Surgical Management ofOSA: Adenotonsillectomy
229
15
instrument with a maximum score of 126, assesses physical symptoms, daytime functions, sleep disturbance,
emotional distress, and caregiver concerns [14]. They
found that neither BMI nor the OSA-18 correlated with
tonsil size using any of the scales, but adenoid size did
correlate with the OSA-18 score.
Adenoid size is usually graded based on obstruction of the nasopharyngeal airway by exible endoscopy in clinic, on lateral X-ray ndings, or at the time of
T&A.Intraoperatively, the percent of obstruction of the
choana by the adenoid pad is graded from 0% to 100%
in a similar manner to the Brodsky tonsillar scale (grade
1: 0–25%, grade 2: 26–50%, grade 3: 51–75%, and grade
4: 76–100%). With endoscopy, adenoid size preoperatively is most accurately graded by assessing the percent
of obstruction caused by adenoid hypertrophy on surrounding structures, including the vomer, soft palate, and
torus tubaris. Parikh et al. proposed a new endoscopic
grading system based on contact of the adenoid pad
with surrounding structures. When the adenoid pad was
completely isolated abutting no structures, it was given a
grade 1. Grade 2 assignment was given if torus tubaris
was obstructed, grade 3 if torus tubaris and vomer were
obstructed, and grade 4 if torus tubaris, vomer, and soft
palate at rest were obstructed. Its use was validated with
an intergrader agreement Kappa score of 0.71 (0.62 for
residents and 0.83 for consultant physicians) indicating
good reproducibility of grading between participants [15].
15.4.2 Polysomnography
Polysomnography (PSG) is the gold standard for the
diagnosis and quantication of OSA. However, PSG
is expensive, cumbersome, and often unavailable in
children. A 2004 systematic review found the diagnostic accuracy of history and physical exam in predicting OSA to be only 55% when compared to PSG [16].
Nonetheless, it is not routinely performed in the majority
of children prior to T&A.In fact, PSG is only obtained
in about 10% of children undergoing T&A for SDB [11].
In a survey of pediatric otolaryngologists, 17% did not
have access to a pediatric sleep laboratory, and the average wait time was over 6weeks [17].
However, PSG should be obtained prior to T&A in
certain populations of children. The American Academy
of Otolaryngology– Head and Neck Surgery, in 2011,
published guidelines on the indication for PSG prior
to T&A [18]. PSG was recommended routinely in children with obesity, Down syndrome, craniofacial abnormalities, neuromuscular disorders, sickle cell disease, or
mucopolysaccharidoses. This reects increased perioperative risks and the likelihood of persistent OSA after
T&A in children with signicant co-morbidities. The
guidelines also recommend obtaining a PSG if tonsil size
does not correlate with reported severity of symptoms,
that is, small tonsils and severe symptoms, or need for
surgery is unclear. Postoperative PSG is recommended in
children with severe OSA or persistent symptoms.
Guidelines have also been published by the American
Academy of Pediatrics and the American Academy of
Sleep Medicine that differ from those published by the
American Academy of Otolaryngology – Head and
Neck Surgery and reect more routine use of PSG prior
to T&A.The AAP guidelines published in 2012 recommend obtaining a PSG in all children with symptoms
and signs of OSA or referring to a specialist, especially
when PSG is not immediately available, and to repeat
the PSG post-T&A in patients who are obese, have OSA
sequela, signicant OSA preoperatively or remain symptomatic [19]. The AASM guidelines, published in 2011,
state that PSG is indicated preoperatively when T&A is
considered for OSA, post-T&A when symptoms persist
in patients with preoperative mild OSA, and post-T&A
in all patients with preoperative moderate–severe OSA,
obesity, neurologic disorders, or craniofacial anomalies
that narrow the upper airway [20].
15.4.3 Clinical History
When PSG is not obtained, the decision to proceed
with T&A often relies on clinical history supported by
an evaluation of tonsillar size. Many studies have been
performed on the utility of several symptom-related
instruments, mostly in the form of questionnaires, to
successfully predict OSA. However, no tool has been
shown to be specic and sensitive for diagnosing OSA.
Ishman et al. evaluated the ability of the OSA-18
quality of life instrument to predict OSA in comparison
to PSG.Using a cut-off of a total symptom score of
≥60 (out of 126) and obstructive AHI of ≥1 on PSG,
the OSA-18 had 100% specicity and 50% sensitivity
in white children, while only 67% specicity and 56%
sensitivity in non-white children. The sensitivity, also
known as the true positive rate, determines the probability of correctly identifying those with the condition.
Therefore, regardless of race, the OSA-18 had an unacceptably high false-negative rate. The specicity, also
known as the true negative rate, determines the ability
of a test to correctly identify those without the condition. In this study, the OSA-18 had an unacceptably
high false-positive rate in non-white children but no
false- positive rate in white children. Therefore, a score
of ≥60 on the OSA-18in white children is likely to correctly diagnose OSA.However, given the poor sensitivity, a score≤60 on the OSA-18 does not rule out OSA,
regardless of race. It was determined that the OSA-18
cannot be used in lieu of PSG to accurately predict OSA
in either population [21].
230
A. G. Ordemann and R. B. Mitchell
15
Chervin etal. rst analyzed the use of the 22-item
Sleep-Related Breathing Disorder (SRBD) scale within
the larger Pediatric Sleep Questionnaire (PSQ) to predict
OSA.A score of 0.33 (33%) was indicative of OSA on
PSG with a sensitivity and specicity of 83% and 87%,
respectively, for patients with AHI ≥5, and a sensitivity
and specicity of 88% and 87%, respectively, for patients
with AHI ≤5 [22]. A follow-up retrospective analysis
of their longitudinal study by the same group revealed
an increased odds ratio of 2.80 for OSA (AHI ≥1) for
a high SDRB score (1 SD above the mean). Utilizing
the same SBRD cut-off value of 33%, OSA (AHI ≥1)
was accurately predicted in 74% of cases with a sensitivity and specicity of 78% and 72% respectively. They
also found that improvement in the SBRD score 1-year
post-T&A more accurately reected improvements in
the Attention Decit Hyperactivity Disorder (ADHD)
scale than did PSG results [23], reecting its ability to
predict behavioral outcomes better than PSG.Both were
equally effective at predicting improvement in daytime
sleepiness and attention quotient.
These ndings were replicated as part of the
Childhood Adenotonsillectomy (CHAT) multi-institutional study. The SDRB portion of the PSQ predicted
postsurgical improvement of subjective measures of
morbidity including executive dysfunction, behavior,
quality of life, and sleepiness. Those with greater symptom burden preoperatively were more likely to improve.
In contrast, the severity of OSA on PSG did not independently correlate with improvement in these areas
postoperatively. The authors reected that the SDRB,
a one-page questionnaire, is an easy, quick method of
assessing the severity of many subjective OSA-related
symptoms and should be utilized in addition to, not in
place of, objective PSG measures in predicting the surgical response of a child with OSA following T&A [24].
In another CHAT study paper, demographic and
physical exam data as well as three subjective questionnaires as lled out by the parents– PSQ, OSA-18, and
Epworth Sleepiness scale (an 8-item questionnaire out
of 24 points evaluating daytime sleepiness)– were analyzed for their ability to determine OSA severity, when
compared with PSG [25]. Despite several correlations
on their linear regression analyses, no statistical model
accurately predicted OSA severity. They hypothesized
that the subjective nature of the questionnaires may
contribute to their poor efcacy as a predictive tool.
the caregiver to ask questions and receive well-informed
answers. Any child old enough to partake in the decision should be included in the process. The specics
of the consent process vary between institutions, state,
and country. However, risk discussion should include
those of general anesthesia, airway re, intraoperative
and postoperative bleeding, need for blood transfusion,
pain, perioperative respiratory complications (requiring the need for reintubation or non-invasive positive
pressure ventilation), perioperative cardiac complications, death, nausea, vomiting, bad breath, referred ear
pain, velopharyngeal fever, dehydration, reduced oral
intake, prolonged hospitalization, readmission, delayed
return to normal activities and/or school, regrowth of
adenoids or tonsils, disturbance of taste, need for further surgery, atlantoaxial subluxation, velopharyngeal
insufciency, nasopharyngeal stenosis, continued SDB,
change in voice/speech, damage to the teeth, lips, gums,
tongue, pharynx, or eye [5]. In a prospective cohort
study in 2016 in which the informed consent process
was videotaped and the parents’ ability to recall risks
and benets was assessed, only one-third of the surgical risks were recalled. Benets were recalled easier than
risks, with 11.9% of parents reporting that no risks were
mentioned. Interestingly, parents who were less likely
to recall surgical risk were more likely to proceed with
surgery [26]. This highlights the importance of spending
adequate time on counseling and documentation during
the consent process, as well as having the consent witnessed by a non-partial party.
One of the most common risks includes posttonsillectomy hemorrhage (PTH). The 2011 clinical
practice guidelines report a rate of primary PTH (within
24hours of surgery) and secondary PTH as 0.2–2.2%
and 0.1–3%, respectively [5]. A 2017 comparative effectiveness review of 104 studies of low-to-moderate risk
bias including 6299 children reported an average PTH
of 4.2% for total tonsillectomy and 1.5% for partial tonsillectomy. PTH was greater for those undergoing tonsillectomy for SDB than those for recurrent infections.
However, signicant overlap in the condence intervals
precludes any denitive conclusions [27]. Readmission
rate in most studies was less than 5%. In a larger data
sample of 1,778,342 children, four deaths were reported
following tonsillectomy. No one surgical instrument
technique provided signicantly better rates of PTH.
15.5 Preoperative Consent
Informed consent is an important and necessary part
of any surgical procedure including T&A. Adequate
discussion regarding the risks, benets, and alternatives to T&A is important with ample opportunity for
15.6 Preoperative Assessment
15.6.1 Surgical Setting
Many patients can undergo T&A safely as an outpatient including at a free-standing surgical center.
Determining which patients can undergo surgery
Surgical Management ofOSA: Adenotonsillectomy
231
15
outside of a hospital setting is crucial. Any patients
with severe OSA (AHI> 10), Down syndrome, cerebral palsy, sickle cell disease, neuromuscular disorders,
craniofacial abnormalities, obesity (body mass index
>30 or >95th percentile BMI z-score), failure to thrive,
recent respiratory infection, major heart disease,
bleeding diatheses, age less than three, or any other
signicant co-morbidity should be observed overnight
for increased risk of complications [5]. Inpatient setting after T&A may also be considered for those who
live a far distance from a medical center or those with
a higher American Society of Anesthesia Class score
(3 or greater) [28].
In addition to postoperative overnight observation,
patients with sickle cell disease are usually admitted
24 hours preoperatively for aggressive hydration and
transfusion with a goal of <40% hemoglobin S ratio
and/or >100g/L hemoglobin level. Their pain should be
well-controlled postoperatively and uid regimen adequate to avoid a sickle pain crisis [28].
15.6.2 Special Laboratory Evaluation or
Imaging
In general, no routine preoperative laboratory analysis
is obtained prior to T&A in children unless there is a signicant bleeding history, or a personal or family history
of a bleeding disorder. There have been several studies
investigating the utility of obtaining routine preoperative coagulation studies such as activated partial thromboplastin time (aPTT), prothrombin time (PT), and/or
international normalized ratio (INR) prior to T&A to
exclude a risk of hemorrhage [29–31]. The studies report
low sensitivity and specicity and show that routine
preoperative coagulation studies are not cost- efcient.
Screening with coagulation studies and/or a hematology
consult may be warranted if clinical history suggests a
major bleeding episode and/or bleeding disorder. The
presence of a coagulation disorder should not be an
absolute contraindication to T&A and is based on the
risks and benets for the individual child. In a recent
retrospective review, only 1 of the 14 patients with an
identied hematologic disorder experienced a postoperative bleed [32].
Routine imaging is also not performed. However,
patients with Down syndrome should undergo preoperative cervical spine exion, extension, and lateral X-rays
as well as a neurologic exam. Approximately, 10–20%
of Down syndrome patients are at risk of atlantoaxial
subluxation which can lead to permanent neurologic
decits. Therefore, any patients with neurologic decits
on exam or atlantodental interval >4.5mm should be
referred to a spine specialist [33].
15.6.3 Screening Tools forIdentifying
At-Risk Children inthePerioperative
Period
In order to properly counsel patients and their families,
it is important to try and predict which children may
be at increased risk for perioperative respiratory adverse
events (PRAE), especially when PSG has not quantied
OSA severity. Tait etal. investigated the predictive value
of individual questions within the SRBD questionnaire
as part of a standardized approach to quickly identify
children at risk for PRAE. They found that answering
yes to ve questions pertaining to the child’s sleep at
night (snoring loudly, snoring more than half the night,
struggling to breath, witnessed apneas, and awakening
unrefreshed) to be strongly indicative of PRAE. The
STBUR scale was developed from this, isolating these
ve questions within the SBRD, to identify at-risk children [3]. PRAE likelihood increased threefold if three
questions were true (answered yes) and tenfold if all ve
questions were true.
Similarly, in another multidisciplinary study involving anesthesiology, pulmonology, and otolaryngology,
six questions from the PSQ reliably identied children
with OSA that had perioperative complications leading to a prolonged post-anesthesia care unit (PACU)
stay and supplemental oxygen need [34]. This short
PSQ questionnaire had a sensitivity of 89% and specicity of 41% for identifying OSA when compared with
PSG.Both OSA on PSG and a score of >2 out of 6 on
the questionnaire were signicantly associated with the
need for supplemental oxygen in PACU, while neither
was associated with a prolonged PACU stay.
15.7 Tonsillectomy Technique:
Extracapsular Versus Intracapsular
The modern and most common method of tonsillectomy performed is extracapsular (ECT), also known
as complete tonsillectomy. In this method, the tonsil is
fully removed by dissecting in a bloodless fascial plane
outside of the tonsillar capsule and medial to the pharyngeal musculature (superior pharyngeal constrictor,
palatoglossus, and palatopharyngeus). Popularized by
Fuller in 1930 [35], in order to perform the technique
correctly and in a bloodless fashion, suture ligation or
cauterization of feeding vessels is required with the latter being more common today.
Postoperative pain and hemorrhage are the two
major postoperative concerns after performing tonsillectomy. Depending on the electrocautery device selected,
the heat dissipation within the tonsillar bed can reach up
232
A. G. Ordemann and R. B. Mitchell
15
to 400°C and may spread to surrounding tissues. This
is thought to be a major cause of the postoperative pain
associated with tonsillectomy [36]. The pain associated
with extracapsular tonsillectomy does not subside until
the pharyngeal musculature is remucosalized [35].
Due to the concerns over postoperative pain associated with cautery techniques, intracapsular tonsillectomy (ICT) also known as tonsillotomy or partial
tonsillectomy is regaining popularity. Once popular in
the early twentieth century, it was deserted due to concerns over the residual tonsil causing reinfection and an
increase in sequela such as rheumatic or scarlet fever
[36]. Koltai etal. proposed that decreased pain with ICT
would occur by leaving a small amount of tonsillar tissue on the tonsillar bed/pharyngeal musculature that
acts as a “biological dressing” reducing inammation
and subsequent pain. He also hypothesized an inverse
relationship between post-tonsillectomy hemorrhage
and the amount of tonsillar tissue removed, arguing that
the diameter of the vessels (entering at the capsule) is
larger, the deeper (or lateral) one gets into the tonsil [35].
Proponents for ICT argue that it reduces postoperative pain and thus unplanned admissions for pain and/or
dehydration. A recent meta-analysis by Kim etal. supported this by showing ICT (adenoidectomy included)
performed with a microdebrider signicantly reduced
postoperative pain, readmissions, analgesia amount,
and days to normal diet and activity as compared to
extracapsular techniques [37]. A separate meta- analysis
of 15 studies by Lee etal. investigated the efcacy of ICT
(645 individuals) versus ECT (620 individuals) for the
management of OSA.In this meta- analysis, a comparison between microdebrider and Coblator ICT technique
revealed no difference in postoperative pain or bleeding
outcomes. Similarly, they found signicantly reduced
postoperative pain, postoperative bleeding, analgesic
use, days until normal activity, and diet resumed within
the ICT group as compared to the ECT group [38].
Advocates for ECT argue that ICT leads to a signicant increase in tonsillar regrowth, which could obscure
the benet of tonsillectomy for OSA. Both metaanalyses demonstrated a signicant increase in tonsillar
regrowth [37, 38], with a relative risk ratio of 6.02in the
ICT group versus ECT group in one meta-analysis [38].
In a multi-center retrospective case series of 870 children
undergoing microdebrider ICT, Solares etal. showed a
regrowth rate of only 0.46% but over a relatively short
follow-up period of 14months [39].
The clinical signicance of tonsillar regrowth is
unknown as no prospective, randomized controlled
trial has been performed evaluating postoperative
polysomnography (PSG) results between ICT and
ECT cohorts. In a recent case series of 70 children
undergoing microdebrider- assisted ICT signicant
reductions in AHI, mean and nadir oxygen satura-
tion were seen between preoperative and postoperative
PSG. However, the study lacked a comparison ECT
or control group [40]. In another 2016 retrospective
review of the efcacy of microdebrider-assisted ICT
versus ECT on postoperative PSG parameters in
OSA, an ECT cohort of 52 children, who were signicantly more obese and older, were compared to an
ICT cohort of 37 children. Both ECT and ICT cohorts
had high postoperative OSA cure rates of 79% and
76% respectively, but the follow-up in this study was
short with a small study population and lack of control for age and obesity. Furthermore, children with
neurological or craniofacial disorders were excluded
[41]. The largest retrospective review included 75 ICT
and 93 ECT patients. As in the previous study, the ICT
cohort was signicantly younger and less obese, while
improvements in AHI, oxygen saturation nadir, and
postoperative complication rates were similar for the
two groups. The only postoperative complication that
was signicantly different between the groups was tonsillar regrowth, 2.2% versus 0% in the ICT and ECT
cohorts respectively [42].
In Lee et al.’s meta-analysis, tonsillar regrowth did
not have adversely affect or worsen AHI [37]. However,
most of the studies in both meta-analyses utilized the
OSA-18 to evaluate the clinical impact of tonsillar
regrowth. Both meta-analyses revealed no difference
in the quality of life when utilizing these instruments
between the ICT and ECT cohorts [37, 38].
While data from preliminary case series and retrospective cohort reviews show promise in the success rates
in OSA cure after ICT, all studies lack a large enough
sample size or long enough follow-up. Therefore, it is
imperative to have higher level quality of evidence on
the effect of tonsillar regrowth on postoperative AHI in
normal, overweight, and obese children as well as those
with medical co-morbidities with OSA prior to adopting ICT as an equal or superior method.
15.8 Instrumentation
15.8.1 Tonsillectomy
There are a variety of surgical instruments used to perform T&A including, but not limited to, bipolar radiofrequency ablation, monopolar electrocautery, bipolar
electrocautery, microdebrider, harmonic scalpel, thermal wielding, KTP or CO2 laser, ultrasonic dissection,
and cold steel techniques (Snare). The most common
techniques are reviewed here.
Bipolar radiofrequency ablation, also known as
coblation or plasma-mediated ablation, has become an
increasingly popular technique since being introduced
in 1998. The Coblator creates tissue dissociation by
Surgical Management ofOSA: Adenotonsillectomy
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producing an alternating current within a sodium-rich
medium such as isotonic saline producing a maximum
thermal temperature of 70°C [43].
In a 2017 Cochrane review including 29 studies and
2561 participants undergoing extracapsular dissection,
coblation was compared with other surgical techniques
for tonsillectomy to determine intraoperative and postoperative morbidity as well as cost [44]. Heterogeneity
between studies precluded conclusions on cost, need
for reoperation or postoperative infections. There was
equal risk of primary (risk ratio (RR)=0.99; 95% condence interval (CI) 0.48–2.05) and elevated secondary
(RR=1.36; 95% CI 0.95–1.95) post-tonsillectomy hemorrhage rates, lower pain rates at day 1, and equal pain
rates at day 7 but the quality of the evidence was poor.
The evidence supporting coblation over other techniques is lacking but costs are often higher. However, the
evidence that does exist suggests it of equal efcacy and
safety to other methods with possibly lower pain rates.
Many favor this technique as the lower thermal injury is
presumed to create less collateral tissue injury, while still
obtaining hemostasis.
Monopolar electrocautery (i.e., Bovie) is another
widely used technique. Monopolar electrocautery is a
handheld unipolar device that utilizes a ground electrode placed on the patient to complete the circuit. As
compared with the Coblator, the device does not require
a saline-rich medium and creates its thermal effect by
a unipolar electrode with direct current with temperatures reaching 600–700°C [45]. It should not be used in
patients with metallic implant devices such as a cochlear
implant, debrillator, or pacemaker.
The Agency for Healthcare Research and Quality
2017 systematic review of the literature regarding tonsillectomy reached few conclusions on the effectiveness of
different surgical techniques. They identied four randomized controlled trials (RCTs) comparing coblation
and electrocautery. Half of the RCTs found a return to
normal diet and activity sooner in the coblation group,
while the other half found no difference. In three small
RCTs comparing monopolar electrocautery with cold
steel dissection, return to normal activity and diet was
quicker in the electrocautery group in one but in cold
steel dissection in two RCTs. Therefore, the literature
consists of mixed evidence regarding the effectiveness
of different surgical techniques for tonsillectomy with
very little high quality of evidence to support the use of
one device over another.
15.8.2 Adenoidectomy
Similar to tonsillectomy, various instruments can be
used to remove the adenoid pad. Traditionally, adenoids
were removed with a curette– a blind, cold steel tech-
nique. When utilizing this technique, the tissue can be
removed en bloc and a specimen obtained. Bleeding can
be difcult to control and requires packing with a vasoconstrictive agent. Most utilize a more modern technique of indirect visualization with an angled mirror.
Once visualized, the adenoid pad can be removed with
suction electrocautery (suction bovie), bipolar radiofrequency ablation (Coblator), or microdebrider. However,
the microdebrider also requires hemostasis via packing
or cautery. Bleeding rates following adenoidectomy are
markedly less frequent than after tonsillectomy.
15.9 Postoperative Management
15.9.1 Pain
Pain management after T&A varies between providers and institution. There are a variety of approaches
to pain management that include over-the-counter and
narcotic pain medications. Pain management should be
started with over-the-counter analgesics (that are often
prescribed) before the consideration of narcotics [5].
Abstaining from narcotics is especially important in
obese children with severe OSA, as the sensitivity to opioid side effects such as respiratory depression is amplied.
A safety investigation was launched by the FDA in 2012
following several deaths post-T&A in children receiving an appropriate weight-based dose of codeine [46].
In February 2013, the Food and Drug Administration
(FDA) issued a black box warning following a safety
investigation of the use of codeine after T&A in children under 12 years of age following reported deaths
in a number of children deemed “ultra-rapid metabolizers.” This refers to the highly polymorphic CYP2D6
enzyme, which is part of the P450 system responsible
for conversion of the pro-drug codeine to morphine
[47] (see .
is converted into morphine. However, in “ultra-rapid
metabolizers,” a generally acceptable dose of codeine is
converted to a larger, fatal amount of morphine in the
liver. The ultra-rapid metabolizer phenotype incidence
varies by ethnic group and is most common in those of
Ethiopian, Arab, and North African descent [48]. In
April 2017, the FDA expanded their warning against
the use of both codeine for post-T&A pain control in
children 12–18years of age if they have OSA, chronic
lung conditions, or are obese. The AAP has also issued
a broad recommendation against the use of codeine in
all children under the age of 18 as both an analgesic and
antitussive [49].
A contraindication, the FDA’s strongest warning,
has also been issued for tramadol use in patients less
than 18 years of age following T&A [50]. Tramadol,
also a prodrug, is metabolized via the CYP2D6 pathway
Fig.15.2). Normally, only 10% of codeine
234
A. G. Ordemann and R. B. Mitchell
Drug Active or prodrug Enzyme pathway Active metabolites
Codeine Prodrug CYP2D6 Morphine
Morphine Active UGT2B7 M6G (Morphine 6-glucuronide)
Tramadol Prodrug CYP2D6 O-DMT (O-demethylated)
Hydrocodone Active CYP2D6 (major)
CYP3A4 (minor)
Oxycodone Active CYP3A4 (major)
CYP2D6 (minor)
. Fig. 15.2 Narcotic pain medicine properties
Hydromorphone
Noroxycodone
Oxymorphone
15
as well as to an active metabolite O-DMT that acts on
the μ-opioid receptor. Severe respiratory depression following T&A in an “ultra-rapid metabolizer” has been
published [51].
While there are multiple recommendations against the
use of codeine and tramadol, there is relatively little published about the use of other narcotic pain medications
in the post-T&A period. Hydrocodone and oxycodone
are two oral narcotic medications often used in adults for
pain control. Hydrocodone is an active drug with twice the
potency of morphine whose major route of metabolism is
also via the CYP2D6 pathway to create hydromorphone,
also known as dilaudid [51]. This would lead to an eightfold
greater concentration of hydromorphone in “ultra-rapid
metabolizers.” Furthermore, serious drug–drug interactions may occur due to its equal metabolism through the
CYP34A pathway which is utilized by several different
drug classes. A fatal overdose in a child taking clarithromycin (utilizing the CYP34A pathway) concurrently with
hydrocodone has been reported [52]. Oxycodone is also an
active drug metabolized primarily through the CYP34A
enzyme pathway and minimally via the CYP2D6 pathway.
While this may lessen the risk of opioid toxicity in ultrarapid metabolizers, data regarding its safety in children are
lacking. Both are schedule II drugs (as of 2014 for hydrocodone). Schedule II drugs cannot be called in, faxed,
emailed, or relled [53]. The AAP recommends against the
use of narcotic analgesics when outpatient pain control is
needed given the relative similarities between the drugs and
lack of safety information in children [49].
In the 2011 clinical practice guidelines from the
American Academy of Otolaryngology – Head and
Neck Surgery (AAO-HNS) [5], weight-based dosing
of over-the-counter medication was recommended for
post-T&A pain control delivered via a scheduled basis
orally or rectally if oral medications are refused. There
is no evidence to support better pain control from the
utilization of medication on a scheduled rather than an
as-needed basis. However, caregiver compliance is vital
to the achievement of proper postoperative pain control,
and caregivers may be more vigilant if given instructions
to dispense medications on a scheduled basis. They also
emphasized the need for caregiver education to encourage pain assessment frequently in the postoperative
period. Both ibuprofen and acetaminophen are recommended by the AAO-HNS as over-the-counter analgesics for post-T&A control [5]. The use of perioperative
local anesthetics, antibiotics, ketorolac, or topical agents
was not recommended.
Once debated, the use of non-steroidal antiinammatory medications is not associated with an
increased risk of PTH. A Cochrane review in 2005
including 13 randomized controlled trials with about
1000 children found no signicant increased risk of PTH
with the use of non-steroidal anti-inammatory medications compared with other analgesics with an odds
ratio of 0.91 for PTH requiring reoperation [54]. This
excludes ketorolac which is thought to have a signicantly higher risk of PTH ranging from 4.4% to 18% [5].
A recent multi-institution cross-sectional survey of caregiver’s perceptions of post-tonsillectomy pain revealed
superior pain control with ibuprofen as compared to
narcotic use alone or with an ibuprofen/narcotic combination, though the children receiving ibuprofen were
signicantly younger [55].
15.9.2 Diet
Post-tonsillectomy diet recommendations are highly
variable among surgeons despite a paucity of data to
support one diet over another. Common variations
include a fully liquid diet, soft diet, dairy-free diet,
citrus- free diet, or unrestricted (regular) diet. A systematic review of post-tonsillectomy diet advice published
in 2017 includes evidence from 17 articles, three of
which were small RCTs in the 1990s. The review could
not group the data into a meta-analysis due to the heterogeneity of the studies. However, all three RCTs found
no difference between restricted and non-restricted diets
in terms of postoperative pain, bleeding, or healing [56–
59]. However, one study found lower pain scores in the
group given ice-pops within 4hours of surgery versus
those who did not receive an ice-pop [59].
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15.9.3 Follow-Up
All patients with OSA should be contacted 3 months
following T&A to ensure symptomatic improvement.
Roughly 75% will be asymptomatic and can be discharged [60]. If symptoms persist, a full head and neck
exam should be completed including a exible laryngopharyngoscopy to exclude upper airway obstruction
and specically adenoidal obstruction. A trial of nasal
saline and steroid spray should be started and an allergy
evaluation considered. Repeat PSG should be obtained
in cases when there is concern for persistent OSA, particularly in the medically complex children, that is, those
who are obese or with Down syndrome, craniofacial, or
neuromuscular disorders.
15.10 Expected Outcomes by Population
T&A does not always normalize OSA. Higher rates of
persistent OSA occur in children with obesity, neuromuscular, craniofacial, or chromosomal disorders. Additional
caregiver counseling is needed in these children.
15.10.1 General Population
Within the general pediatric population, the efcacy
of T&A to resolve OSA (denition ranges from AHI
reduced less than 1 to less than 5 depending on the
study) was reported to be 82.9% in a 2006 meta-analysis.
A mean reduction of AHI by 14 events per hour was
reported [61]. Similarly, in a prospective cohort study of
79 healthy children, OSA resolution following T&A was
90% when dened as AHI <5 and 71% when dened as
AHI <1 [60]. A 100% resolution of OSA occurred in all
children with a preoperative AHI≤10. Also, persistent
snoring was reported in 28% of children after T&A and
all with persistent OSA were symptomatic.
15.10.2 Complex Children
In a 2009 meta-analysis, including 23 studies, Friedman
etal. reported on the cure rate of OSA following T&A
[62]. Nine studies included “complicated” patients
dened as morbid obesity, having severe OSA and/or
under the age of 3. The cure rate was 66% when dened
as AHI <5 and 60% when dened as AHI <1. The mean
preoperative and postoperative AHI was 18.6 and 4.9
respectively. The cure rates for uncomplicated and complicated patients were73.8% and 38.7% respectively.
Despite this, the overall mean change in AHI from pre-
operative to postoperative was greater in the complicated patients than in the uncomplicated patients (22
versus 12). The study showed that improvement in OSA
occurs regardless of patient population, but resolution
is less likely in certain populations particularly in children with morbid obesity.
15.10.2.1 Obese Children
In another 2009 meta-analysis assessing the cure rate
in obese children, T&A improved OSA severity with a
weighted mean decrease in AHI of 18.3 events and mean
increase in oxygen saturation nadir of 6.3%. However,
T&A was curative in only 12% of cases (reduced AHI
<1) [63]. This is an important consideration given that
the rate of pediatric obesity (dened as BMI at or above
the 95th percentile of the sex-specic CDC BMI-for-age
charts) in the United States as of 2012 data is 16.9%
[64], but the prevalence of OSA in those with obesity is
59% [2].
15.10.2.2 Down Syndrome
Children with Down syndrome have a prevalence of
OSA of 57–66%. T&A is a common procedure in children with Down syndrome in a pediatric otolaryngology
practice [65]. However, the rate of incomplete resolution
mirrors that of the obese population and this must be
considered when counseling caregivers about the best
intervention. In a study of 27 patients with Down syndrome, OSA resolved in 29.6% of patients, while 44.4%
had at least a 50% reduction in AHI [65]. Greater reduction in AHI was seen in those with more severe OSA
(higher AHI) preoperatively while it worsened with
hypothyroidism. They also noted worsening of the central apnea index (CAI) in patients with congenital heart
disease (in 71%) and hypothyroidism (in 32%).
In a recent 2017 systematic review of T&A for OSA
in children with Down syndrome, 51% had improvement in AHI [66]. The improvement in AHI was equal
regardless of initial OSA severity. Within the qualitative
analysis, several studies revealed no change in sleep efciency, sleep stage distribution, or arousal index despite
improvement in AHI, while up to 75% required postoperative positive airway pressure (PAP) or nocturnal
oxygen [67].
Many factors contribute to incomplete resolution of
OSA in children with Down syndrome. These include a
narrowed airway, macroglossia, lingual tonsillar hypertrophy, propensity for collapsibility of airway, and a
myriad of comorbidities such as congenital heart disease,
hypothyroidism, obesity, and lung disease [66]. All of this
should be considered when counseling caregivers. Despite
this, T&A is considered a rst-line treatment in these children but with a high likelihood of persistent OSA.