Avaliação polissonográfica e da patência nasal após expansão rápida da maxila no tratamento de crianças com apneia obstrutiva do sono

Abstract

Introduction: Obstructive Sleep Apnea (OSA) in children is a relevant pediatric issue due to the impacts it has on the quality in patients’s lives. This syndrome is described as the total or partial collapse of the upper airways during sleep, because of an imbalance between the space of the upper airway and the relative size of the lymphoid tissue, with adenotonsillar hypertrophy as its main cause. Even so, other causes may be associated, such as obesity, alteration of neuromotor tone and skeletal deficiencies, including: maxillomandibular deficiencies being in length or transverse, flexion of the skull base or reduction of it. In this sense, it was noticed that orthodontics can assist in the treatment of OSA by means of Rapid Maxillary Expansion (RME) to treat patients with maxillary atresias when adenotonsillar surgery is not sufficient to improve the disorder, since it also promotes respiratory gain by increasing nasal width. Objectives: to evaluate the effect of RME on nasal patency and polysomnographic findings in children with OSA. Methodology: This was a prospective study with 26 children between 4 and 11 years of age, with OSA, adenotonsillar hypertrophy with surgical indication, maxillary atresia and without systemic problems, who underwent RME treatment with a Hyrax appliance, evaluated at two different times: T0 (before RME) and T1 (after the 4-month period of RME containment, when the appliance has been removed). In these two stages, they were submitted to type 1 polysimography (PSG) (evaluation of the apnea/hypopnea index AHI; basal, mean, minimum and maximum oxyhemoglobin saturation; oximetry time below 90% and oxyhemoglobin desaturation index) and active anterior rhinomanometry (AAR), with the following variables analyzed: right and left nasal inspiratory airflow (RNF and LNF inspiratory), expected nasal inspiratory airflow (NIF Expected), NIF Total, Nasal Flow in %. For AAR measurements, a control group was also introduced, containing 26 children aged 4 to 10 years and with the same characteristics as the study group, except for the fact that they had not undergone RME treatment. Results: Of the 26 patients in the study group, 61.5% were female, with a median of 7 years. In the comparison of PSG, we obtained a decrease with a statistical difference in the AHI variables, saturation time less than 90% and oxyhemoglobin desaturation index (p=0.0005; p=0.0280; p=0.0111, respectively) and an increase with a statistical difference in the mean and minimum oxyhemoglobin saturations (p=0.0045 and p=0.0295, respectively), which indicates an improvement in apnea after RME. In the AAR, in the study group, all variables showed statistical difference at T1 (p<0.0005), with all parameters improving in the treated patients. Comparing the AAR values between the study groups and the control group at T0 there was no difference between the groups and at T1 the values of RNF and LNF inspiratory, NIF Expected, NIF Total and Nasal Flow in % were significantly higher in the study group than in the control group, indicating that RME treatment improves the respiratory capacity of children with OSA compared to those who did not undergo treatment. Conclusions: RME has improved polysomnographic and rhinomanometry aspects in patients with OSA and can be considered a therapeutic option for the treatment of the syndrome when the patients have skeletal atresia and/or when adenotonsillar surgery is not sufficient to improve the disorder.