Diaphragm plication reduces sleep-related obstructive disturbances in surgically selected patients with unilateral diaphragmatic dysfunction: pilot observational data

INTRODUCTION: Unilateral diaphragmatic dysfunction can cause exertional and postural dyspnoea, along with sleep-related breathing disturbances. Diaphragm plication alleviates daytime symptoms, but its effects on sleep have not been evaluated in detail. METHODS: We analysed prospectively collected observational data in 12 patients undergoing surgical plication for unilateral diaphragmatic dysfunction. Standardised pre- and postoperative assessments included ratings of exertional dyspnoea, orthopnoea and antepnoea (D-VAS), quality of life (VSRQ), spirometry (sitting and supine), transdiaphragmatic twitch pressures, and polysomnography (PSG). Sleep-disordered breathing was evaluated using standard PSG indices including the obstructive apnoea-hypopnoea index (oAHI), measured globally and during REM. RESULTS: Following plication, dyspnoea decreased and orthopnoea and antepnoea were nearly abolished (p = 0.0123 and p = 0.0001, respectively). VSRQ improved (p = 0.0078). Supine vital capacity rose from 52.5% to 75.0% predicted (p = 0.0010), and supine VC drop decreased from 15.1% to 2.65% (p = 0.0068). Twitch pressures increased significantly. oAHI decreased from 15.5 to 8.5 events·h⁻¹ (not significant after multiplicity correction). REM AHI decreased from 43.0 [24.5-66.9] to 19.0 [11.5-23.3] events·h⁻¹ (p = 0.0020), and REM hypopnoea index from 19.5 to 11.0 (p = 0.0098). Strong correlations were found between REM AHI changes and both FRC and expiratory reserve volume (ERV). CONCLUSION: In patients with unilateral diaphragmatic dysfunction, diaphragm plication is associated with improved REM-related obstructive events. This may relate to lung volume restoration. These exploratory findings suggest that prospective studies are needed to determine the usefulness of systematic pre-post plication PSG for patient selection and outcome evaluation.