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Remotely Reported Peak Flow Meter Measurements Demonstrate Disease Progression, Predict Need for Surgery in Patients with Subglottal Stenosis

by Linda Kossoff •

Can remote use of a peak flow meter (PFM) predict severity of subglottic stenosis (SGS) and surgical timing?

BOTTOM LINE

PFM measurements can adequately demonstrate disease progression and predict the need for surgery in patients with SGS disease and, together with Dyspnea Index (DI) scores, may be a useful tool for remotely following these patients.

BACKGROUND: SGS is a highly recurrent type of laryngotracheal stenosis that usually requires long-term monitoring and multiple operative interventions. Care has relied on in-person history, physical exams, and pulmonary function testing (PFT). Studies have investigated the ability of PFT measurements to diagnose/assess SGS and predict the need for surgery.

STUDY DESIGN: Prospective study.

SETTING: Department of Otolaryngology–Head & Neck Surgery, University of North Carolina, Chapel Hill, N.C.

SYNOPSIS: Researchers enrolled 35 adult patients with an SGS diagnosis who presented at a single institution’s voice center between June 2020 and June 2021. Patients were given PFMs and instructed on their use. At-home PFM data were regularly submitted to researchers via smartphone. Clinic visits included PFT and administration of DI survey. Sixteen patients underwent surgical intervention. Preoperative and postoperative PFTs, PFM measurements, and DI scores were compared. Resulting data demonstrated a strong correlation between at-home, patient-reported PFM measurements and peak expiratory flow rate derived from a controlled clinical setting. For patients, PFM provided a simpler way to track their individual peak expiratory flow rates and required less travel and equipment resources. In predicting the timing of operative intervention, PFM was the most specific (79%) and DI the most sensitive (88%). Authors noted that postoperative PFM measurements tended to peak a few weeks postoperatively, potentially due to post-intervention inflammation and edema, and suggested that this may also be important to consider when interpreting postoperative PFTs. This study was limited by a small sample size.

CITATION: Park M, Tie K, Davis H, et al. Can the remote use of a peak flow meter predict severity of subglottic stenosis and surgical timing? Laryngoscope. 2023;133:628-633