The single most important piece of paper obtained from a sleep study is a hypnogram, which provides an all night view of the patient’s sleep parameters.
Explore This IssueDecember 2007
You need to understand the terms used in the sleep report and what the tests represent. It is important to have a good relationship with your sleep expert colleague so that he or she can help you interpret the study results. Also, the same lab should be used for all studies, Dr. Friedman emphasized.
In the current era of evidence-based medicine, outcomes research is needed to validate treatment modalities, explained Ron B. Mitchell, MD, Professor of Otolaryngology at St. Louis University School of Medicine and the Cardinal Glennon Children’s Medical Center in St. Louis. Dr. Mitchell reviewed data from the past five years related to treatment of SDB and outcomes.
A review of 14 studies using polysomnography (PSG) to evaluate outcomes in children with SDB and obstructive sleep apnea (OSA) found that T&A had success rates ranging from 79% to 92% (Brietzke et al. Head Neck Surg 2006). Limitations of this review were that the studies had small sample sizes, studied different disorders, used different sleep labs, and had different definitions of success, he said.
-Norman R. Friedman, MD
Another review by Dr. Mitchell and colleagues found that sleep parameters improved significantly post-surgery in 80 healthy nonobese children with SDB. After T&A, 71% to 94% were normalized, depending on the sleep parameter. In general, around 80% to 85% of children get better, he said.
The most dramatic improvements were observed in children who had more severe SDB, but every child who had surgery showed some improvement. Every child with AHI < 10 normalized; 73% with AHI > 10 normalized. Tonsil size was not a predictor of improvement, he said.
Conversely, 15% to 20% of healthy normal-weight children do not normalize following surgery. This means that of the 250,000 T&A procedures performed annually in the United States, about 50,000 children do not have normalized sleep parameters following surgery.
Quality of Life After T&A
Dr. Mitchell said that the impact of SDB on children’s quality of life is considerable, and he believes it may be underestimated. Children with SDB have significantly worse quality of life compared with healthy controls, similar to the quality of life of children with juvenile rheumatoid arthritis and asthma. This is particularly true for the emotional, behavioral, and parental impact, Dr. Mitchell commented.