CURRENT Essentials of Critical Care.pdf

Chapter 7 Pulmonary Disease 87■■■Obstructive Sleep Apnea SyndromeEssentials of Diagnosis• Excessive daytime somnolence with evidence of upper airwayobstruction occurring at any site above glottis during sleep• Obstructive events last 10–90 seconds and terminate witharousal from sleep leading to sleep fragmentation• Accessory muscle use, intercostal retractions, paradoxical inspiratorychest wall movements observed during apneas• Acute hypercapnia, hypoxemia, disrupted sleep, hemodynamicalterations occur with obstruction and can lead to systemic hypertensionand cor pulmonale• Bradycardia with pauses up to 13 seconds and ventricular ectopyseen in severe cases during desaturations• Daytime hypoventilation not common• Common characteristics: male sex, age over 40 years, habitualsnoring, observed apneas, systemic hypertension• Risk factors: obesity, tonsillar hypertrophy, craniofacial abnormalitieswith narrowing of posterior oropharynx, edema of airwaystructures, diminished neural reflexes or ventilatory controlDifferential Diagnosis• Simple snoring • Cheyne-Stokes respirations• Central sleep apnea syndromeTreatment• Nasal continuous positive airway pressure (CPAP) is treatmentof choice; acts as pneumatic splint preventing airway closure• Oxygen therapy alone can prolong apneic events and should beused with careful monitoring• Endotracheal intubation or tracheostomy highly effective for selectpatients failing noninvasive ventilation• Lateral decubitus position or elevated head of bed preferred• Use of sedative-hypnotic and centrally suppressing agents contraindicated• No role for respiratory stimulants or carbonic anhydrase inhibitors■ PearlObstructive sleep apnea syndrome should be suspected in obese hypersomnolentsnorers who are hypertensive.ReferenceStrollo PJ Jr: Indications for treatment of obstructive sleep apnea in adults.Clin Chest Med 2003;24:307. [PMID: 12800786]