Pell Ann Wardrop, MD, an otolaryngologist and medical director of the St. Joseph Sleep Wellness Center in Lexington, Ky., agreed. “Unless the child has risk factors such as obesity, craniofacial abnormalities, or neuromuscular disease, I feel a preoperative sleep study is optional,” she said. “I do the study when there is some question or doubt if a TA is needed.” She added that if only one sleep study is done, she recommends a postoperative sleep study. “It is vital to know when residual obstructive sleep apnea is present so the child can be appropriately treated,” she added. “Some of the treatment options, such as maxillary expansion, must be performed before the child matures.”
Explore this issue:September 2016
Dr. Brietzke described the thrust of the guideline this way: “If there is a lack of consistency within a physical exam and a history, you need a sleep study,” he said. “But if there is strong clinical evidence of sleep apnea, you can proceed with TA without a sleep study.”
Expanding on this statement, Dr. Breitzke highlighted the need for otolaryngologists to understand the difference between sensitivity and specificity of diagnostic tools when determining the value of a sleep study prior to TA. The clinical literature, he said, shows that the sensitivity of the clinical exam, combined with a history, is sufficient for establishing which child is a candidate for TA. “If a child comes in with large tonsils and has a convincing history of obstructive sleep apnea, it is reasonable to perform a tonsillectomy without a sleep study in many cases,” he said, adding that the statistics are “strongly on your side.”
He emphasized that the opposite is not true, however—ruling out sleep apnea is more difficult without a sleep study. “When you’re trying to exclude sleep apnea, or if the child has discordant tonsil size or if the history doesn’t fit, that is where a sleep study can be useful,” he said. He highlighted the importance of a sleep study after surgery in patients who remain symptomatic to obtain a clear diagnosis of sleep apnea prior to treatment with more surgery or continuous positive airway pressure (CPAP).
Both Drs. Ishman and Brietzke discussed the importance of tonsil size as a key component in the diagnostic assessment of whether or not to consider a sleep study.
Dr. Brietzke pointed out the difficulty of getting a clear estimate of tonsil size and the limited ability of old clinical scales for accurate measurement. He urged otolaryngologists to make a concerted effort to incorporate the use of three-dimensional measures from tools such as MRI or volumetric analyses of tonsils to get a more accurate estimate of tonsil size rather than just taking a quick look.