Mechanistic insights from sleep endoscopy related to oronasal mask failures: a case report.

ABSTRACT

A 71-year-old male with severe obstructive sleep apnea (OSA) and nasal septal deviation presented to a positive airway pressure (PAP) alternatives clinic due to persistent obstructive events on both continuous PAP (CPAP) and bilevel PAP (BPAP) therapy delivered via oronasal mask. He underwent drug-induced sleep endoscopy with PAP titration (DISE-PAP) to determine the mechanism of oronasal mask failure. A nasal mask was also applied and titrated for comparison. DISE-PAP showed tongue base collapse which resolved at low pressure using a nasal mask. Application of an oronasal mask increased minimum therapeutic PAP level. Tightening the mask worsened tongue base collapse, which was not resolved by increasing the PAP level. Following nasal surgery, the patient was able to tolerate nasal CPAP at low therapeutic pressure, which resulted in both objective and subjective improvement is his OSA. This case highlights the ability of DISE-PAP to determine the mechanistic cause of oronasal mask failure.