key: cord-0990136-e0od04hi authors: Santhosh, Lekshmi; Block, Brian; Kim, Soo Yeon; Raju, Sarath; Shah, Rupal J.; Thakur, Neeta; Brigham, Emily Pfeil; Parker, Ann Marie title: Response date: 2022-01-06 journal: Chest DOI: 10.1016/j.chest.2021.07.046 sha: 8e2e331bee64c31d3f86406cb9c7596a2585344d doc_id: 990136 cord_uid: e0od04hi nan Editor's Note: Authors are invited to respond to Correspondence that cites their previously published work. Those responses appear after the related letter. In cases where there is no response, the author of the original article declined to respond or did not reply to our invitation. The Next Challenge for Post-COVID-19 Clinics Scale To the Editor: We read with great interest the review by Santosh et al 1 published in CHEST (August 2021) regarding emerging clinic designs for patients who experience post-acute sequelae of COVID-19 (PASC). We suggest a focus on centering resources in primary care. Many PASC clinics have significant access issues because of limited resources for this growing population that often requires high-touch and accessible care. 2 To manage volume, many clinics exclude patients based on severity of their initial COVID-19 infection. Although PASC is more likely in the hospitalized population, stratification of ambulatory care resources by such history may be inappropriate. [3] [4] [5] Additionally, although streamlined access to specialty care is essential, a separate clinic often leads to care happening in parallel to the primary care relationship. We propose an alternative strategy that may be more scalable and adaptable. First, train primary care clinicians in the fundamentals of PASC care. Second, provide a mechanism to engage additional support with a low barrier of entry and quick turnaround. We use "econsults," an electronic chart message sent to a pool of internists with a special interest in PASC, to answer questions that arise. Our team uses standardized assessments and care pathways when responding, which allows us to comanage mild-to-moderate presentations. Finally, complex patients who are identified by e-consult are triaged to a multidisciplinary case conference that regularly reviews cases in "tumor-board"-style to coordinate care, expedite specialty evaluation if needed, and develop comprehensive care plans. This approach scales quickly and meets the framework proposed by Santosh et al. 1 We hope to spark additional innovation in the care of this growing population. To the Editor: We read the letter to the editor from Drs Yu and Kelly regarding our published review 1 with great interest. We agree that successful long COVID/post-COVID care structures require primary care involvement, either by way of direct incorporation or close collaboration, depending on local resources. In both cases, post-acute sequelae of COVID-19 (PASC) clinics can serve as hubs for dissemination of rapidly evolving PASC knowledge via events such as continuing medical education conferences and one-on-one consultations. We appreciate the e-consult and tumor board framework that you have implemented and welcome such creativity in leveraging institutional strengths to customize a multidisciplinary approach to the care of patients recovering from COVID-19. We also wish to emphasize the importance of concentrated clinical and research efforts to recognize patterns in PASC. A benefit of dedicated PASC clinics is an opportunity to define, test, and operationalize chestjournal.org effective care strategies. Such evidence-based care can then be disseminated broadly to all physicians who encounter patients with PASC to advance the care of this growing population. For example, it is important for clinical and research leaders to remain up to date with evolving PASC guidelines and the development of core outcome measures. Local resources and capacity will determine whether these clinical structures derive leadership from primary care, pulmonary medicine, physical medicine and rehabilitation, or other specialties as is the case in PASC clinics across the United States. We advocate strongly for a concentrated leadership model, regardless of the primary discipline, while the knowledge base is being developed. This provides a central resource to coordinate the care of often complex presentations. The pre-COVID-19 literature in recovery from acute care that requires hospitalization, including in the ICU, has jumpstarted comprehensive care of survivors of COVID in these populations and provided a substantive framework for the care of those who did not require hospitalization. Importantly, PASC clinics provide a structure for the identification of similarities and differences between patients with initial mild vs moderate-to-severe COVID-19 illness to further tailor management approaches. Ultimately, necessary and sufficient care will require cooperation across multiple disciplines, especially primary care, to advocate for essential resources; together, we can overcome this challenge. We applaud your novel approach and look forward to learning about more innovative methods from our national and international colleagues as we collectively join our patients in confronting PASC/long COVID. Rapid design and implementation of post-COVID-19 clinics Almost a Third of People with 'mild' Covid-19 Still Battle Symptoms Months Later, Study Finds Attributes and predictors of long COVID Rapid design and implementation of post-COVID-19 clinics Central Sleep Apnea Adaptive Servo-Ventilation, Intelligent Volume-Assured Pressure Support, and Hypoventilation To the Editor:Treatment-emergent central sleep apnea (TEC) is the development or persistence of central sleep apneas during positive airway pressure (PAP) therapy in subjects with predominantly OSA. Risk factors for TEC and the role of loop gain are well-reviewed by Zeineddine and Badr 1 in an issue of CHEST (June 2021). However, we disagree with some of their statements and use a different approach to TEC.They say "BPAP (bilevel positive airway pressure) delivers fixed tidal volume for a given pressure support (PS) level ," but tidal volume varies with respiratory effort, muscle activity, airway patency, and body position. Lower tidal volume (and higher PCO 2 ) can occur supine vs not supine and rapid eye movement (REM) vs non-REM for a given pressure support.They say "ASV (adaptive servo-ventilation) is contraindicated in patients with reduced ejection fraction.", but the American Association of Sleep Medicine recommends not using ASV only for patients with left ventricular ejection fraction (LVEF) #45% and predominant moderate or severe central sleep apnea. 2 The Treatment of Sleep-Disordered Breathing with Predominant Central Sleep Apnea by Adaptive Servo Ventilation in Patients with Heart Failure (SERVE-HF) trial 3 of patients with LVEF <45% excluded patients with primarily OSA and thus patients with TEC. The SERVE-HF trial also found that ASV improved outcomes in patients with Cheyne Stokes respiration <20% of recording time, 4 which suggests that the ASV risk is low in the TEC population.