A new clinical practice guideline developed by a task force of the American Academy of Sleep Medicine provides updated recommendations for the treatment of centralsleep apnea. Available online as an accepted paper in theJournal of Clinical Sleep Medicine, the guideline updates the AASM’s previous practice parameters published in 2012 and 2016. Among other significant updates, it incorporates evidence from recent studies of adaptive servo ventilation and addresses new developments including the introduction of transvenous phrenic nerve stimulation as a novel therapy. “Central sleep apnea is a complex form of sleep-disordered breathing that requires individualized, patient-centered care,” said lead author Dr. M. Safwan Badr, chair of the AASM task force and chair of the department of internal medicine at Wayne State University School of Medicine in Detroit, Michigan. “It is essential for the treating clinician to prioritize improvements in quality of life and functional outcomes rather than focusing exclusively on the elimination of disordered breathing events.” Central sleep apnea involves disruption of sleep due to an absence or reduction in breathing effort coupled with a reduction or cessation in airflow. This breathing instability can occur with various clinical conditions includingheart failure, obstructive sleep apnea, and use ofopioids. The pathogenesis of centralsleepapnea can vary depending on the underlying clinical condition. All nine clinical recommendations in the guideline are designated as “conditional,” meaning that they reflect a lower degree of certainty and require the clinician to use clinical judgment while considering the patient's values and preferences to determine the best course of action. These recommendations support six treatment options for specific etiologies of central sleep apnea: continuous positive airway pressure, bilevel positive airway pressure with a backup rate, adaptive servo ventilation, low-flow oxygen, oral acetazolamide, and transvenous phrenic nerve stimulation. The guideline states that clinicians must consider the underlying condition contributing to breathing instability when selecting and optimizing therapy for central sleep apnea. Adaptive servo ventilation received a conditional recommendation for central sleep apnea due to multiple etiologies. However, because of questions raised by one clinical trial involving patients with central sleep apnea and systolic heart failure, the guideline emphasizes that treatment with adaptive servo ventilation in patients with heart failure with reduced ejection fraction should be limited to centers with experience and should include close monitoring and follow-up. The guideline includes a new conditional recommendation for transvenous phrenic nerve stimulation for primary central sleep apnea and central sleep apnea due to heart failure. This treatment involves the use of an implantable device that turns on automatically and works continuously to monitor and stabilize breathing. In 2017 the Food and Drug Administration approved the device to treat moderate to severe central sleep apnea in adult patients. Because the treatment requires an invasive procedure, is not universally accessible, and is associated with high costs, the guideline advises that it may be more appropriate to consider other treatments first. To develop the guideline, the AASM commissioned a task force of sleep medicine physicians with expertise in treating central sleep apnea. They crafted clinical practice recommendations based on a systematic review of the literature and an assessment of the evidence according to the GRADE process, taking into consideration the certainty of evidence, beneficial and harmful effects, patient values and preferences, and resource use. The draft guideline was posted for public comment, and the AASM board of directors approved the final recommendations. Recommendations The AASM suggests using continuous positive airway pressure (CPAP) over no CPAP in adults with CSA due to the following etiologies: primary CSA, CSA due to heart failure, CSA due to medication or substance use, treatment-emergent CSA, and CSA due to a medical condition or disorder. (Conditional recommendation, low certainty.) The AASM suggests using bilevel positive airway pressure (BPAP)with a backup rateover no BPAP with a backup rate in adults with CSA due to the following etiologies: primary CSA, CSA due to medication or substance use, treatment-emergent CSA, and CSA due to a medical condition or disorder. (Conditional recommendation, very low certainty). The AASM suggests against the use of BPAPwithout a backup ratein adults with CSA due to the following etiologies: primary CSA, CSA due to heart failure, CSA due to medication or substance use, treatment-emergent CSA, and CSA due to a medical condition or disorder. (Conditional recommendation, very low certainty). The AASM suggests using adaptive servo ventilation (ASV) over no ASV in adults with CSA due to the following etiologies: primary CSA, CSA due to heart failure, CSA due to medication or substance use, treatment-emergent CSA, and CSA due to a medical condition or disorder. (Conditional recommendation, low certainty). Remarks: Prior to initiation of ASV, patient-provider shared decision-making is recommended, and treatment decisions should be based on expectations of symptomatic or quality-of-life improvement. Treatment with ASV in patients with heart failure with reduced ejection fraction (HFrEF) should be limited to centers with experience, along with close monitoring and follow-up. The AASM suggests using low-flow oxygen over no low-flow oxygen in adults with CSA due to heart failure. (Conditional recommendation, low certainty). The AASM suggests using low-flow oxygen over no low-flow oxygen in adults with CSA due to high altitude. (Conditional recommendation, very low certainty). Remarks: Patients with transient and mild CSA symptoms at high altitude may reasonably decline treatment with low-flow oxygen. The AASM suggests using oral acetazolamide over no acetazolamide in adults with CSA due to the following etiologies: primary CSA, CSA due to heart failure, CSA due to medication or substance use, treatment-emergent CSA, and CSA due to a medical condition or disorder. (Conditional recommendation, low certainty). The AASM suggests using oral acetazolamide over no acetazolamide in adults with CSA due to high altitude. (Conditional recommendation, very low certainty). The AASM suggests using transvenous phrenic nerve stimulation (TPNS) over no TPNS in adults with CSA due to the following etiologies: primary CSA and CSA due to heart failure. (Conditional recommendation, very low certainty). Remark: Given that TPNS requires an invasive procedure, is not universally accessible, and is associated with high costs, it may be more appropriate to consider other treatments first. M. Safwan Badr, Rami N. Khayat, J. Shirine Allam, Suzanne Hyer, Treatment of central sleep apnea in adults: an American Academy of Sleep Medicine clinical practice guideline, Journal of Clinical Sleep Medicine, https://doi.org/10.5664/jcsm.11858