In some conditions continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BIPAP) therapy alone fails to provide satisfactory oxygenation. In these situations oxygen (O2) is often being added to CPAP/BIPAP mask or hose. Central sleep apnea and obstructive sleep apnea (OSA) are often present along with other chronic conditions, such as chronic obstructive pulmonary disease (COPD), congestive heart failure, pulmonary fibrosis, neuromuscular disorders, chronic narcotic use, or central hypoventilation syndrome. Any of these conditions may lead to the need for supplemental O2 administration during the titration process. Maximization of comfort, by delivering O2 directly via a nasal cannula through the mask, will provide better oxygenation and ultimately treat the patient with lower CPAP/BIPAP pressure. 1. Introduction Obstructive sleep apnea (OSA) is a complex medical disorder, characterized by repetitive upper airway collapse during sleep. The disease affects individuals of all ages and predisposes to multiple comorbidities, including increased risk of cardiovascular disease . Perioperative apneas appear to be multifactorial in nature. Sedatives and anesthetics have been shown to decrease pharyngeal muscle tone and therefore predispose to apnea . Meanwhile, the patient’s normal arousal responses and reflexes are also compromised by anesthetics . This predisposes to apneic episodes which can be more severe than those associated with natural sleep. While many patients present for surgery with undiagnosed OSA, it is currently recommended that patients who receive ambulatory CPAP preoperatively should continue to have CPAP administered in the perioperative period. Otherwise, the optimal management of OSA in the perioperative period has yet to be elucidated . 2. Case Report A 51-year-old obese male, with a history of daytime fatigue, presented to the anesthesia holding area for urgent appendectomy. He had previously undergone a sleep study several months before with apnea/hypopnea index (AHI) of 35 and a maximum desaturation to the low 60’s. Patient vital signs included a blood pressure of 140/85？mm/Hg, heart rate of 95 beats per minute and respiratory rate of 16 per minute with a temperature of 38 centigrade. His pulse oximetry (SaO2) reading was 91% with 2 liters/minute of nasal oxygen flow. Chest radiography did not show any pathology. He was brought to operating room, and anesthesia was induced with propofol and succinylcholine in a rapid sequence technique. The trachea was intubated with the aid of a GlideScope.
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