Authors (including presenting author) :
Yeung Gerry, Kwok KL, Leung SY, Chan Eric, Hou Andy,Tsui CK, Lau MY, Mak MK, Ng DK
Affiliation :
Department of Paediatrics, Kwong Wah Hospital
Introduction :
Tonsillectomy and adenoidectomy (T&A) is generally accepted as the primary treatment in obstructive sleep apnea (OSA) with adenotonsillar hypertrophy. T&A can improve OSA but does not completely eliminate it. In a previous meta-analysis, the success rate was 55% when cure was defined as apnea-hypopnea index (AHI) < 1. Naturally, positive airway pressure (PAP) treatment should be considered in children refused T&A or who continued to have residual OSA after T&A including obesity, craniofacial syndrome, Down syndrome, neuromuscular disorders, and severe preoperative sleep apnea.
Currently, the gold standard for initiating PAP treatment is for patients to undergo a PAP titration in an attended sleep laboratory. However, because of the rapidly rising demand for PAP treatment, there was a long waiting time for PAP titration. In Dec 2015, waiting PAP titration for routine cases had been increased to 8 months. In order to shorten the long waiting time and meet the increasing demand on PAP treatment for OSA children under limited manpower resources (one RPSGT at Paed/KWH), a new drug-induced sleep endoscopy (DISE) service model was developed to shorten the waiting time for PAP treatment has been piloted since Jan 2016.
Objectives :
To monitor the waiting time for PAP treatment and to evaluate the effectiveness of new service model.
Methodology :
A retrospective cohort study was conducted to collect data during Jan 2016 to Dec 2019 after the pilot of new DISE service model has been implemented. We introduced the use of auto-titration PAP to initiate PAP treatment, together with pulse oximeter (SpO2) and transcutaneous monitor (EtCO2) to document the presence of sleep-related desaturation and hypoventilation before DISE. During DISE, the PAP pressure would be titrated during the procedure, and the endoscopist would check if there was any obvious alleviation of obstruction visually. Patients would be discharged after optimization of the PAP treatment after DISE.
Result & Outcome :
There were 318 children (70.8% male, mean age: 12.1+/-5.2 years old) diagnosed with OSA and underwent DISE. The mean AHI was 8.0+/-13.8 and mean BMI was 20.9+/-6.5 kg/m2. Multilevel severe obstruction (score =3) was found in 30.0% of patients. The majority of the severe (score=3) of obstruction was tongue base (73.8%), followed by velum (55.3%), lateral pharyngeal wall (50.6%), nasal (40.9%), adenoids (34.6%), and supraglottis (33.3%).
After DISE, 34.9% (111/318) children were arranged follow up at multidisciplinary sleep surgery clinic for mandibular advancement device (MAD), rapid maxillary expansion (RME) and +/- lingual tonsillectomy; 26.4% (84/318) children received PAP treatment as the sole long-term treatment; 25.8% (82/318) children were arranged follow up at ENT joint clinic for T&A; 10.4% (33/318) children were arranged follow up at sleep clinic for optimizing the control allergic rhinitis, myofunctional training and weight reduction; 2.5% (8/318) children were received high-flow nasal cannula (HFNC) therapy. Sixty-fifth children received short-term PAP treatment before surgery or orthodontic treatment. The 84 children who received long-term PAP treatment had treatment started within 1-2 weeks after endoscopy. The mean of average daily usage 5.3 +/- 2.6 hours was noted during follow up at technology dependent children (TDC) clinic or respiratory ground round.
As compared with routine waiting time for PAP treatment, auto-PAP titration have decreased the waiting time. However, we can provide up to two auto-titrations of PAP per week due to limited resources. The main limiting factor lies upon the provision of a specialist TDC nurse to provide training for patients, arrange quotations for parents and provide consultation service for inpatient and pre-discharge planning. Future planning of TDC services must take into account this limiting factor in order to meet the growing demand.
