Persistent OSA After Adenotonsillectomy in Down Syndrome
A 7-year-old girl with Down syndrome is referred for persistent sleep-disordered breathing. She had adenotonsillectomy 8 months ago for obstructive sleep apnea. Her parents report loud snoring, witnessed apneas, and daytime sleepiness; she has fallen asleep in class. Physical exam: BMI 22 kg/m² (>95th percentile), macroglossia, midface hypoplasia, no tonsils. Polysomnography before surgery showed obstructive AHI 22/h; a repeat study now shows obstructive AHI 15/h, nadir SpO2 82%, and peak ETCO2 58 mmHg. She has no symptoms of heart failure. Her thyroid function was last checked 2 years ago and was normal.
1. Why does this child have persistent OSA after adenotonsillectomy? What is the next step in management?
Read the worked answer
Persistent OSA after adenotonsillectomy is common in Down syndrome because of hypotonia, midface hypoplasia, macroglossia, obesity, and a narrow pharyngeal airway. The repeat PSG shows severe OSA (obstructive AHI 15/h, nadir SpO2 82%, hypercapnia with ETCO2 58 mmHg). The next step is positive airway pressure therapy, usually CPAP, with titration during an overnight study. Weight management and evaluation for hypothyroidism are also important. Repeat adenoidectomy is not indicated unless adenoid regrowth is documented.
2. How would you initiate and support CPAP in a child with Down syndrome?
Read the worked answer
Initiate CPAP with behavioral desensitization: show the mask, practice wearing it while awake, use positive reinforcement, and involve child life specialists. Choose a pediatric mask that accommodates midface hypoplasia. Perform an overnight titration study to find the effective pressure. Educate parents about adherence, skin care, and humidification. If CPAP is not tolerated after a structured trial, consider bilevel positive airway pressure, maxillofacial surgery, or tracheostomy in severe refractory cases. Follow-up with sleep medicine within 4–6 weeks.
3. What comorbidities should you screen for, and why?
Read the worked answer
Screen for hypothyroidism with TSH and free T4 because untreated hypothyroidism can worsen OSA, obesity, and daytime sleepiness. Obtain an echocardiogram to assess for pulmonary hypertension from chronic hypoxemia, even without heart failure symptoms. Monitor blood pressure and lipids for metabolic syndrome. Also assess for iron deficiency, which can worsen sleepiness, and for dental crowding. A multidisciplinary approach with sleep medicine, cardiology, endocrinology, and otolaryngology is appropriate.