CrossTalk proposal: the human upper airway does behave like a Starling resistor during sleep

Phenotypes of Velopharyngeal Tube Law in Obstructive Sleep Apnea

OBJECTIVE

The biomechanics of upper airway collapse in obstructive sleep apnea (OSA) remains poorly understood. The goal of this study is to compare the area-pressure relationship (tube law) of the velopharynx at peak inspiration and peak expiration.

STUDY DESIGN

Cross-sectional.

SETTING

Academic tertiary medical center.

METHODS

The velopharyngeal tube law was quantified in a convenience sample of 20 OSA patients via step reductions in nasal mask pressure during drug induced sleep endoscopy (DISE). The velopharyngeal airspace cross-sectional area was estimated from endoscopy while luminal pressure was recorded with a catheter. The tube law was quantified for nasal mask pressures from 14 to 0 cmH2O at peak inspiration and at peak expiration in all patients. The tube law was also quantified during the breathing cycle at a constant nasal mask pressure of 4 cmH2O in 3 patients representing different phenotypes.

RESULTS

Velopharyngeal compliance (the slope of the tube law) was not statistically different in the peak inspiration versus peak expiration tube laws. Three phenotypes were observed, namely inspiratory collapse (phenotype 1), expiratory collapse (phenotype 2 = palatal prolapse), and a mostly stable airway during inspiration and expiration that collapsed as CPAP was reduced (phenotype 3).

CONCLUSION

Velopharyngeal compliance is not significantly different at peak inspiration and peak expiration, which suggests that muscle tone is low when luminal pressure is above the closing pressure. Additional studies are needed to investigate how different phenotypes of velopharyngeal collapse may affect therapeutic outcomes.

Does cosmetic rhinoplasty affect sleep quality and/or contribute to the development of obstructive sleep apnea?

OBJECTIVE

Rhinoplasty can reduce nasal airways' resistance. This study evaluates the effects of rhinoplasty on sleep quality, daytime drowsiness, and obstructive sleep apnea (OSA).

METHODS

In this prospective cohort study, 80 rhinoplasty candidates were examined before and six months after rhinoplasty to evaluate symptom changes. STOP-BANG, Pittsburgh Sleep Quality Index (PSQI), and Epworth Sleepiness Scale (ESS) questionnaires, and nocturnal polysomnography were used, respectively, to screen for OSA, assess sleep quality, assess daytime drowsiness, and confirm results.

RESULTS

Seventeen men (21.2%) and 63 women (78.8%) were studied. PSQI results showed an increase only in post-operative sleep disturbance items (p = 0.04). STOP-BANG showed an increase in apnea (p = 0.06) and a decrease in snoring (p = 0.06), which were both insignificant. The polysomnography tests confirmed the results of the questionnaires.

CONCLUSION

Contrary to popular belief, rhinoplasty does not increase snoring, sleep disorders, or apnea.

Anatomical determinants of upper airway collapsibility in obstructive sleep apnea: A systematic review and meta-analysis

Upper airway (UA) collapsibility is one of the key factors that determine the severity of obstructive sleep apnea (OSA). Interventions for OSA are aimed at reducing UA collapsibility, but selecting the optimal alternative intervention for patients who fail CPAP is challenging because currently no validated method predicts how anatomical changes affect UA collapsibility. The gold standard objective measure of UA collapsibility is the pharyngeal critical pressure (Pcrit). A systematic literature review and meta-analysis were performed to identify the anatomical factors with the strongest correlation with Pcrit. A search using the PRISMA methodology was performed on PubMed for English language scientific papers that correlated Pcrit to anatomic variables and OSA severity as measured by the apnea-hypopnea index (AHI). A total of 29 papers that matched eligibility criteria were included in the quantitative synthesis. The meta-analysis suggested that AHI has only a moderate correlation with Pcrit (estimated Pearson correlation coefficient r = 0.46). The meta-analysis identified four key anatomical variables associated with UA collapsibility, namely hyoid position (r = 0.53), tongue volume (r = 0.51), pharyngeal length (r = 0.50), and waist circumference (r = 0.49). In the future, biomechanical models that quantify the relative importance of these anatomical factors in determining UA collapsibility may help identify the optimal intervention for each patient. Many anatomical and structural factors such as airspace cross-sectional areas, epiglottic collapse, and palatal prolapse have inadequate data and require further research.

Mandibular advancement reduces pharyngeal collapsibility by enlarging the airway rather than affecting velopharyngeal compliance

Mandibular advancement devices (MADs) are frequently prescribed for obstructive sleep apnea (OSA) patients, but approximately one third of patients experience no therapeutic benefit. Understanding the mechanisms by which MADs prevent pharyngeal collapse may help optimize MAD therapy. This study quantified the relative contributions of changes in airspace cross-sectional area (CSA) versus changes in velopharyngeal compliance in determining MAD efficacy. Sixteen patients with moderate to severe OSA (mean apnea-hypopnea index of 32 ± 15 events/h) underwent measurements of the velopharyngeal closing pressure (PCLOSE ) during drug induced sedated endoscopy (DISE) via stepwise reductions in nasal mask pressure and recording of the intraluminal pressure with a catheter. Airspace CSA was estimated from video endoscopy. Pharyngeal compliance was defined as the slope of the area-pressure relationship of the velopharyngeal airspace. MAD therapy reduced PCLOSE from a median of 0.5 cmH2 O pre-advancement to a median of -2.6 cmH2 O post-advancement (p = 0.0009), increased the minimal CSA at the velopharynx by approximately 20 mm2 (p = 0.0067), but did not have a statistically significant effect on velopharyngeal compliance (p = 0.23). PCLOSE had a strong correlation with CSA but did not correlate with velopharyngeal compliance. Our results suggest that MADs reduce velopharyngeal collapsibility by increasing airway size as opposed to affecting velopharyngeal compliance. This contradicts the speculation of previous literature that the effectiveness of MADs is partially due to a reduction in velopharyngeal compliance resulting from stretching of the soft palate. These findings suggest that quantification of velopharyngeal CSA pre- and post-MAD advancement has potential as a biomarker to predict the success of MAD therapy.

A solitary sinonasal angiomatous polyp presenting with obstructive sleep apnea in an adult

BACKGROUND

Obstructive sleep apnea (OSA) is frequently encountered in adult sleep disorders and needs careful differential diagnosis.Ear, nose, throat examination, including naso-laryngeal endoscopy, is mandatory in all cases to rule out potential obstructing lesions causing OSA.

CLINICAL PRESENTATION

This report presents a 64-year-old male with snoring, nasal blockage (especially during night-time), and mild OSA. Physical-examination and CT revealed a unilateral vascularized left sinonasal mass extending to the nasopharynx and protruding into the oropharynx during inhalation. Due to suspicions of malignancy or vascular tumor, the patient also underwent contrast MRI. Endoscopic surgery was performed, and the final diagnosis was a sinonasal angiomatous polyp (SAP). SAPs are rare, and this is the first reported case of an adult solitary unilateral angiomatous polyp referral for OSA.

CONCLUSION

Nasal masses need to be considered in the differential diagnosis of patients with obstructive sleep disorders in order to avoid wrong or ineffective treatment.

Impact of Unintentional Air Leaks on Automatic Positive Airway Pressure Device Performance in Simulated Sleep Apnea Events

BACKGROUND

Positive airway pressure (PAP) is the accepted standard treatment for obstructive sleep apnea. In the last decades, automatic PAP (APAP) adjustment modes have been increasingly used. Pressure auto adjustment offers better comfort to the patient and represents a valuable help for the clinician to provide optimal treatment. However, device performance differs among manufacturers. Furthermore, the success of the therapy relies greatly on unintentional air leak level for many reasons, hence the importance to investigate the performance of the most common devices. The aim of this study was to compare the performance of 3 APAP devices from the most common manufacturers in specific conditions (ie, obstructive sleep apnea, central sleep apnea, hypopnea), with and without unintentional air leak.

METHODS

This was a bench test study. Performance tests were conducted on a breathing simulator using a Starling resistor, representing the upper airways, and an adjustable unintentional air leak valve. Three APAP devices (AirSense 10, DreamStation, and Prisma 20A) were tested in different scenarios.

RESULTS

Without unintentional air leak, performance of the 3 devices was similar to existing literature. However, performance was altered with the addition of unintentional air leak in some scenario. The AirSense 10 was not able to respond correctly to obstructive apnea (intraclass correlation coefficient [ICC] 0.021, P = .61) and hypopnea (ICC 0.059, P = .26). Prisma 20A lowest performance was seen during simulated obstructive apnea (ICC 0.708, P < .001). DreamStation lowest performance was seen during simulated hypopnea events (ICC 0.755, P < .001).

CONCLUSIONS

All 3 APAP devices reacted differently to the added unintentional air leak. Performance was altered with some devices, which could affect the therapy success in patients with sleep apnea syndrome. The variability of performance of some APAP devices with unintentional air leak should make clinicians evaluate their use in a home setting.

Obstructive sleep apnea: personalizing CPAP alternative therapies to individual physiology

Introduction The recent continuous positive airway pressure (CPAP) crisis has highlighted the need for alternative obstructive sleep apnea (OSA) therapies. This article serves to review OSA pathophysiology and how sleep apnea mechanisms may be utilized to individualize alternative treatment options.Areas covered: The research highlighted below focuses on 1) mechanisms of OSA pathogenesis and 2) CPAP alternative therapies based on mechanism of disease. We reviewed PubMed from inception to July 2022 for relevant articles pertaining to OSA pathogenesis, sleep apnea surgery, as well as sleep apnea alternative therapies.Expert opinion: Although the field of individualized OSA treatment is still in its infancy, much has been learned about OSA traits and how they may be targeted based on a patient's physiology and preferences. While CPAP remains the gold-standard for OSA management, several novel alternatives are emerging. CPAP is a universal treatment approach for all severities of OSA. We believe that a personalized approach to OSA treatment beyond CPAP lies ahead. Additional research is needed with respect to implementation and combination of therapies longitudinally, but we are enthusiastic about the future of OSA treatment based on the data presented here.

Much Ado about Sleep: Current Concepts on Mechanisms and Predisposition to Pediatric Obstructive Sleep Apnea

Obstructive Sleep Apnea (OSA) is a form of sleep-disordered breathing characterized by upper airway collapse during sleep resulting in recurring arousals and desaturations. However, many aspects of this syndrome in children remain unclear. Understanding underlying pathogenic mechanisms of OSA is critical for the development of therapeutic strategies. In this article, we review current concepts surrounding the mechanism, pathogenesis, and predisposing factors of pediatric OSA. Specifically, we discuss the biomechanical properties of the upper airway that contribute to its primary role in OSA pathogenesis and examine the anatomical and neuromuscular factors that predispose to upper airway narrowing and collapsibility.

Prediction of the obstruction sites in the upper airway in sleep-disordered breathing based on snoring sound parameters: a systematic review

BACKGROUND

Identification of the obstruction site in the upper airway may help in treatment selection for patients with sleep-disordered breathing. Because of limitations of existing techniques, there is a continuous search for more feasible methods. Snoring sound parameters were hypothesized to be potential predictors of the obstruction site. Therefore, this review aims to i) investigate the association between snoring sound parameters and the obstruction sites; and ii) analyze the methodology of reported prediction models of the obstruction sites.

METHODS

The literature search was conducted in PubMed, Embase.com, CENTRAL, Web of Science, and Scopus in collaboration with a medical librarian. Studies were eligible if they investigated the associations between snoring sound parameters and the obstruction sites, and/or reported prediction models of the obstruction sites based on snoring sound.

RESULTS

Of the 1016 retrieved references, 28 eligible studies were included. It was found that the characteristic frequency components generated from lower-level obstructions of the upper airway were higher than those generated from upper-level obstructions. Prediction models were built mainly based on snoring sound parameters in frequency domain. The reported accuracies ranged from 60.4% to 92.2%.

CONCLUSIONS

Available evidence points toward associations between the snoring sound parameters in the frequency domain and the obstruction sites in the upper airway. It is promising to build a prediction model of the obstruction sites based on snoring sound parameters and participant characteristics, but so far snoring sound analysis does not seem to be a viable diagnostic modality for treatment selection.

Effect of tube length on the buckling pressure of collapsible tubes

BACKGROUND

The higher incidence of obstructive sleep apnea (OSA) in men than in women has been attributed to the upper airway being longer in men. The Starling resistor is the paradigm biomechanical model of upper airway collapse in OSA where a collapsible tube (representing the pharynx) is located between two rigid tubes (representing the nasal cavity and trachea). While the Starling resistor has been extensively studied due to its relevance to many physiological phenomena, the effect of tube length on tube collapsibility has not been quantified yet.

METHODS

Finite element analysis of a 3-dimensional collapsible tube subjected to a transmural pressure was performed in ANSYS Workbench. The numerical methods were validated with in vitro experiments in a silicone tube whose modulus of elasticity (361 ± 28 kPa) and dimensions (length = 100 mm, diameter = 22.2 mm, and wall thickness = 1.59 mm) were selected so that tube compliance was similar to pharyngeal compliance in humans during sleep. The buckling pressure (transmural pressure at which the tube collapses) was quantified in tubes of three different diameters (10 mm, 16 mm, and 22.2 mm) and ten length-to-diameter ratios (L/D = 4 to 13), while keeping the wall-thickness-to-radius ratio constant at 0.143.

RESULTS

The absolute value of the buckling pressure decreased from 4.7 to 3.3 cmH₂O (461-324 Pa) when L/D increased from 4 to 13. The buckling pressure was nearly independent from tube length for L/D >10.

CONCLUSIONS

Our finding that longer tubes are more collapsible than shorter tubes is consistent with the higher incidence of obstructive sleep apnea in males than females.

The Physiology and Maintenance of Respiration: A Narrative Review

Chronic pain is one of the most common reasons adults seek medical care and is often managed with opioid analgesics; however, opioids may cause respiratory depression by suppressing various components of respiration. Respiration is the physiological process that facilitates gas exchange and is mediated through the proper function of and communication among central neural control (respiratory drive), sensory input systems, the lungs, and the muscles involved in respiration. Normal respiratory function can be dampened with the use of central nervous system (CNS) depressants and/or underlying health conditions. Patients with chronic pain are often exposed to CNS depressants other than opioids, including benzodiazepines, barbiturates, nonbenzodiazepine sedative-hypnotics, and ethanol, which can function synergistically with opioids to increase the risk of respiratory depression. Some patients may also have underlying health issues, such as obstructive sleep apnea, that can be exacerbated with the use of opioids and other CNS depressants and further contribute to respiratory depression. Clinicians should have a thorough understanding of respiration, recognize how various CNS depressants suppress it, and take necessary steps to mitigate the risk of opioid-induced respiratory depression by collaborating with a multidisciplinary team (i.e., sleep and pain specialists), choosing appropriate medications, and educating patients on the proper use and storage of opioids.

The effect of nasal and oral breathing on airway collapsibility in patients with obstructive sleep apnea: Computational fluid dynamics analyses

Objective

The purpose of this study was to investigate the effect of breathing route on the collapsibility of the pharyngeal airway in patients with obstructive sleep apnea by using computational fluid dynamics technology.

Methods

This study examined Japanese men with obstructive sleep apnea. Computed tomography scans of the nose and pharynx were taken during nasal breathing with closed mouth, nasal breathing with open mouth, and oral breathing while they were awake. Three-dimensional reconstructed stereolithography models and digital unstructured grid models were created and airflow simulations were performed using computational fluid dynamics software.

Results

Airflow velocity was significantly higher during oral breathing than during nasal breathing with open or closed mouth. No significant difference in maximum velocity was noted between nasal breathing with closed and open mouth. However, airflow during nasal breathing with open mouth was slow but rapidly sped up at the lower level of the velopharynx, and then spread and became a disturbed, unsteady stream. In contrast, airflow during nasal breathing with closed mouth gradually sped up at the oropharyngeal level without spreading or disturbance. Negative static pressure during oral breathing was significantly decreased; however, there were no significant differences between nasal breathing with closed or open mouth.

Conclusions

Computational fluid dynamics results during nasal and oral breathing revealed that oral breathing is the primary condition leading to pharyngeal airway collapse based on the concept of the Starling Resistor model. Airflow throughout the entirety of the breathing route was smoother during nasal breathing with closed mouth than that with open mouth.

Airflow limitation in a collapsible model of the human pharynx: physical mechanisms studied with fluid-structure interaction simulations and experiments

The classical Starling Resistor model has been the paradigm of airway collapse in obstructive sleep apnea (OSA) for the last 30 years. Its theoretical framework is grounded on the wave-speed flow limitation (WSFL) theory. Recent observations of negative effort dependence in OSA patients violate the predictions of the WSFL theory. Fluid-structure interaction (FSI) simulations are emerging as a technique to quantify how the biomechanical properties of the upper airway determine the shape of the pressure-flow curve. This study aimed to test two predictions of the WSFL theory, namely (1) the pressure profile upstream from the choke point becomes independent of downstream pressure during flow limitation and (2) the maximum flowrate in a collapsible tube is V I max = A 3 / 2 ( ρ d A / d P ) - 1 / 2 , where ρ is air density and A and P are the cross-sectional area and pressure at the choke point respectively. FSI simulations were performed in a model of the human upper airway with a collapsible pharynx whose wall thickness varied from 2 to 8 mm and modulus of elasticity ranged from 2 to 30 kPa. Experimental measurements in an airway replica with a silicone pharynx validated the numerical methods. Good agreement was found between our FSI simulations and the WSFL theory. Other key findings include: (1) the pressure-flow curve is independent of breathing effort (downstream pressure vs. time profile); (2) the shape of the pressure-flow curve reflects the airway biomechanical properties, so that V I max is a surrogate measure of pharyngeal compliance.

Effect of Nasal Valve Shape on Downstream Volume, Airflow, and Pressure Drop: Importance of the Nasal Valve Revisited

OBJECTIVES

The relative importance of the nasal valve relative to the remainder of the nasal airway remains unknown. The goal of this article was to objectively measure the shape of the nasal inlet and its effect on downstream airflow and nasal cavity volume using a physical model and a physiologic flow model.

METHODS

A patient who had isolated nasal valve surgery and had pre- and postoperative computed tomography scans available for analysis was studied. Nasal inlet shape measurements, computational fluid dynamics, and nasal volume analysis were performed using the computed tomography data. In addition, a physical model was used to determine the effect of nasal obstruction on downstream soft tissue.

RESULTS

The postoperative shape of the nasal inlet was improved in terms of length and degree of tortuosity. Whereas the operated-on region at the nasal inlet showed an only 25% increase in cross-sectional area postoperatively, downstream nonoperated sites in the nasal cavity revealed increases in area ranging from 33% to 51%. Computational fluid dynamics analysis showed that airway resistance decreased by 42%, and pressure drop was reduced by 43%. Intraluminal mucosal expansion was found with nasal obstruction in the physical model.

CONCLUSION

By decreasing the degree of bending and length at the nasal valve, inspiratory downstream nonoperated sites of the nasal cavity showed improvement in volume and airflow, suggesting that the nasal valve could play an oversized role in modulating the aerodynamics of the airway. This was confirmed with the physical model of nasal obstruction on downstream mucosa.

High-Flow, Heated, Humidified Air Via Nasal Cannula Treats CPAP-Intolerant Children With Obstructive Sleep Apnea

STUDY OBJECTIVES

Continuous positive airway pressure (CPAP) is effective but challenging for children with obstructive sleep apnea (OSA). High-flow air via open nasal cannula (HFNC) as treatment in children remains controversial. We report the efficacy of HFNC in children with OSA and CPAP intolerance, a titration protocol, and a discussion of potential mechanisms.

METHODS

Patients aged 1 to 18 years with OSA (defined by obstructive apnea-hypopnea index [OAHI] greater than 1 event/h) and CPAP intolerance were enrolled. Routine polysomnography data obtained during 1 night wearing HFNC was compared with diagnostic data by Wilcoxon rank-sum test.

RESULTS

Ten school-age subjects (representing all patients attempting HFNC at our institution to date) with varied medical conditions, moderate to severe OSA, and CPAP intolerance wore HFNC from 10 to 50 L/min of room air with oxygen supplementation if needed (room air alone for 6 of the 10). HFNC reduced median OAHI from 11.1 events/h (interquartile range 8.7-18.8 events/h) to 2.1 events/h (1.7-2.2 events/h; P = .002); increased oxyhemoglobin saturation (SpO₂) mean from 91.3% (89.6% to 93.5%) to 94.9% (92.4% to 96.0%; P < .002); increased SpO₂ nadir from 76.0% (67.3% to 82.3%) to 79.5% (77.2% to 86.0%; P = .032); decreased SpO₂ desaturation index from 19.2 events/h (12.7-25.8 events/h) to 6.4 events/h (4.7-10.7 events/h; P = .013); and reduced heart rate from 88 bpm (86-91 bpm) to 74 bpm (67-81 bpm; P = .004). Stratified analysis of the 6 subjects with only room air via HFNC, the OAHI, obstructive hypopnea index, and mean SpO₂ still demonstrated improvements (P = .031).

CONCLUSIONS

High-flow nasal cannula reduces respiratory events, improves oxygenation, reduces heart rate, and may be effective for CPAP intolerant children with moderate to severe OSA. Our data suggest HFNC warrants further study and consideration by payers as OSA therapy.

Interventional Drug-Induced Sleep Endoscopy: A Novel Technique to Guide Surgical Planning for Obstructive Sleep Apnea

STUDY OBJECTIVE

One of the challenges of surgery for obstructive sleep apnea (OSA) is identifying the correct surgical site for each patient. The objective of this study was to use drug-induced sleep endoscopy (DISE) and nasopharyngeal tube (NPT) placement to determine the effect of eliminating palatal collapse on the obstruction seen on other segments of the upper airway.

METHODS

Forty-one OSA patients were enrolled in this prospective study. All patients had a polysomnogram followed by DISE. DISE findings were recorded and compared with and without placement of a NPT. Obstruction was graded with a scale that incorporates location, severity, and interval of obstruction.

RESULTS

Most patients (83%) demonstrated multilevel obstruction on initial DISE. With the nasopharyngeal airway in place, many patients with multilevel obstruction had at least a partial improvement (74%) and some a complete resolution (35%) of collapse (p < 0.05). Reduction in collapse was observed at the lateral walls (86%), epiglottis (55%), and tongue base (50%). NPT placement did not significantly alter upper airway morphology of patients with incomplete palatal obstruction or mild OSA.

CONCLUSIONS

To our knowledge, this is the first study to evaluate the effect of soft palatal stenting on downstream pharyngeal obstruction during DISE. Our study provides evidence that reducing soft palatal collapse can reduce negative pharyngeal pressure and thereby alleviate other sites of upper airway obstruction. Taken together, these findings provide a means to identify appropriate candidates for isolated palatal surgery and better direct a minimally invasive approach to the surgical management of OSA.

Bispectral Index in Evaluating Effects of Sedation Depth on Drug-Induced Sleep Endoscopy

OBJECTIVE

To evaluate the effect of sedation depth on drug-induced sleep endoscopy (DISE).

METHODS

Ninety patients with obstructive sleep apnea (OSA) and 18 snorers underwent polysomnography and DISE under bispectral index (BIS)-guided propofol infusion at two different sedation levels: BIS 65-75 (light sedation) and 50-60 (deep sedation).

RESULTS

For the patients with OSA, the percentages of velopharynx, oropharynx, hypopharynx, and larynx obstructions under light sedation were 77.8%, 63.3%, 30%, and 33.3%, respectively. Sedation depth was associated with the severity of velopharynx and oropharynx obstruction, oropharynx obstruction pattern, tongue base obstruction, epiglottis anteroposterior prolapse and folding, and arytenoid prolapse. In comparison, OSA severity was associated with the severity of velopharynx obstruction, severity of oropharynx obstruction, and arytenoid prolapse (odds ratio (95% confidence interval); 14.3 (4.7-43.4), 11.7 (4.2-32.9), and 13.2 (2.8-62.3), respectively). A good agreement was noted between similar DISE findings at different times and different observers (kappa value 0.6 to 1, respectively). A high percentage of arytenoid prolapse (46.7% among the patients with OSA under light sedation) was noted.

CONCLUSIONS

Greater sedative depth increased upper airway collapsibility under DISE assessment. DISE under BIS-guided propofol infusion, and especially a level of 65-75, offers an objective and reproducible method to evaluate upper airway collapsibility. Some findings were induced by drug sedation and need careful interpretation. Specific arytenoid prolapse patterns were noted for which further investigations are warranted.

CLINICAL TRIALS REGISTRATION

http://www.clinicaltrials.gov, identifier: NCT01100554.

COMMENTARY

A commentary on this article appears in this issue on page 965.

Obstructive sleep apnea in children: a critical update

Obstructive sleep apnea (OSA) in children is a highly prevalent disorder caused by a conglomeration of complex pathophysiological processes, leading to recurrent upper airway dysfunction during sleep. The clinical relevance of OSA resides in its association with significant morbidities that affect the cardiovascular, neurocognitive, and metabolic systems. The American Academy of Pediatrics recently reiterated its recommendations that children with symptoms and signs suggestive of OSA should be investigated with polysomnography (PSG), and treated accordingly. However, treatment decisions should not only be guided by PSG results, but should also integrate the magnitude of symptoms and the presence or absence of risk factors and signs of OSA morbidity. The first-line therapy in children with adenotonsillar hypertrophy is adenotonsillectomy, although there is increasing evidence that medical therapy, in the form of intranasal steroids or montelukast, may be considered in mild OSA. In this review, we delineate the major concepts regarding the pathophysiology of OSA, its morbidity, diagnosis, and treatment.