Adenotonsillectomy for Obstructive Sleep-Disordered Breathing in Childhood:The Chania Community Oximetry-Based Study

Obstructive sleep-disordered breathing (SDB) in childhood is a disorder of breathing during sleep characterized by intermittent upper airway obstruction. Snoring, labored breathing and apneas reported by the parents are the most frequent symptoms.Obstructive SDB can result from many different abnormalities including large adenoids and tonsils or obesity.

Intermittent upper airway obstruction during sleep is accompanied by low oxygen or high carbon dioxide in the blood and arousals from sleep. If obstructive SDB is not treated, complications may develop such as: i) enuresis; ii) delay in somatic growth rate; iii) central nervous system morbidity (e.g. hyperactivity and learning difficulties); and iv) elevated blood pressure.

Overnight polysomnography (PSG) is considered the gold-standard method for defining severity of obstructive SDB and subgroups of children with snoring who should be treated. However, PSG is a labor-intensive, time-consuming and expensive diagnostic method, which is not available in many community settings. Thus, there is an urgent need for developing easy-to-use and low-cost diagnostic methods which can be used to determine severity of obstructive SDB and define subgroups of children with snoring and large adenoids and tonsils who will benefit from adenotonsillectomy (AT).

Pulse oximetry is a widely available, non-invasive method which allows continuous monitoring of oxygen transport by hemoglobin. Episodes of upper airway obstruction are frequently accompanied by reductions in the hemoglobin oxygen transport (oxygen desaturation of hemoglobin).The hypothesis of this research project is that subgroups of children with snoring and adenotonsillar hypertrophy and certain abnormalities in oxygenation detected by nocturnal pulse oximetry will benefit from AT in a community setting.

Time in the waiting list for undergoing AT at the Department of Otorhinolaryngology, Chania General Hospital "St. George" is approximately 3 months. In the present study, children will be recruited and randomized in the Active Comparator (AT group) or in the Control Group (No AT group) at the time of the initial clinic visit, if they fulfill the Inclusion Criteria and their parents consent to participation in the study.

Children in the AT group will undergo the baseline study evaluation at the end of the 3-month waiting time and thus immediately prior to AT. They will also undergo the follow-up study evaluation at 3 months postoperatively.

Children in the Control group will undergo their baseline study evaluation at the time of entering the surgical waiting list. They will undergo the follow-up study evaluation 3 months later, immediately prior to AT.

Eligibility Criteria:
Inclusion Criteria:

* Diagnosed with obstructive SDB (snoring \>3 nights/week over the last 6 months)
* Tonsillar size \>2 \[Brodsky 1989\]
* Considered as an AT candidate during the clinic visit by ear, nose and throat (ENT) surgeon

Exclusion Criteria:

* Recurrent tonsillitis defined as at least 3 episodes in each of the last 3 years or at least 5 episodes in each of the last 2 years or at least 7 episodes in the past year.
* Apparent craniofacial anomalies (e.g. Crouzon syndrome or Pierre-Robin sequence)
* Obstructive breathing while awake or any other clinical signs that merit prompt AT as recommended by the treating ENT physician.
* History of clinically important cardiovascular disease or cardiac arrhythmia.
* History of: sickle cell disease; symptomatic asthma; epilepsy; use of sedative medication
* History of: genetic disorders; neurological or neuromuscular disorders
* Use of: systemic or intranasal corticosteroids; montelukast

Footnote

Brodsky score Upon inspection of the oropharynx

* grade 1 indicates that the tonsils are hidden in the pillars
* grade 2 indicates that the tonsils are beyond the anterior pillar and occupy between 25 and 50% of the pharyngeal space
* grade 3 indicates that the tonsils are beyond the pillars but not to the middle and occupy \>50% and up to 75% of the pharyngeal space
* grade 4 indicates that the tonsils occupy \>75% of the pharyngeal space