Inpatient (sleep medicine) and outpatient transitions
In patients hospitalized with the triple overlap syndrome, there are certain considerations that are of special interest. Given comorbid hypercapnia and limited data on NIV superiority over CPAP, a sleep study should not be needed for NIV qualification. In addition, the medical team may consider the following (Figure 1):
1. Noninvasive Ventilation:
a. Maintaining a high-pressure support differential between inspiratory positive airway pressure (IPAP) and EPAP. This can usually be achieved at 8-10 cm H2O, further adjusting to target a tidal volume (Vt) of 8 mL/kg of ideal body weight (IBW).
b. Higher EPAP: To overcome dependent atelectasis, improve ventilation-perfusion (VQ) matching, and better treat upper airway resistance both during wakefulness and sleep. Also, adjustments of EPAP at bedside should be considered to counteract auto-PEEP-related ineffective triggering if observed.
c. OSA screening and EPAP adjustment: for high residual obstructive apneas or hypopneas if data are available on the NIV device, or with the use of peripheral arterial tonometry sleep testing devices with NIV on overnight before discharge.
d. Does the patient meet criteria for oxygen supplementation at home? Wean oxygen off, if possible.
2. Case-managers can help establish services with a durable medical equipment provider with expertise in advanced PAP devices.3. Obesity management, Consider referral to an obesity management program for lifestyle/dietary modifications along with pharmacotherapy or bariatric surgery interventions.
4. Close follow-up, track exacerbations. Device download data are crucial to monitor adherence/tolerance and treatment effectiveness with particular interest in AHI, oximetry, and CO2 trends monitoring. Some patients may need dedicated titration polysomnograms to adjust ventilation settings, for optimization of residual OSA or for oxygen addition or discontinuation.
Conclusion
Patients with the triple overlap phenotype have not been systematically defined, studied, or included in clinical trials. We anticipate that these patients have worse outcomes: quality of life, symptom and comorbidity burden, exacerbation rates, in-hospital mortality, longer hospital stay and ICU stay, and respiratory and all-cause mortality. This is a group of patients that may specifically benefit from domiciliary NIV set-up upon discharge from the hospital with close follow-up. Properly identifying these patients will help pulmonologists and health care systems direct resources to optimally manage this complex group of patients. Funding of research trials to support clinical guidelines development should be prioritized. Triple overlap syndrome is different from COPD-OSA overlap, OHS with moderate to severe OSA, or OHS without significant OSA.