Effects of hydromorphone and dexmedetomidine on diaphragmatic function in patients with acute exacerbation of chronic obstructive pulmonary disease receiving noninvasive ventilation.

Sedative and analgesic agents may negatively influence diaphragmatic performance. This study sought to compare the effects of dexmedetomidine (DEXM) and hydromorphone (HM) on diaphragmatic function among patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) undergoing noninvasive ventilation (NIV). In this open-label randomized controlled trial, 80 patients were randomly assigned to either the HM or DEXM group, with primary endpoints being the alterations in diaphragmatic thickening fraction (DTF) and diaphragmatic excursion (DE). Secondary endpoints included length of hospital stay, duration of NIV, and hospital mortality rates. Safety assessments involved monitoring fluctuations in mean arterial pressure (MAP), heart rate, respiratory rate (RR), minute ventilation, episodes of respiratory depression or hypotension, as well as variations in arterial partial pressure of carbon dioxide and oxygenation index. Results indicated that both DEXM and HM groups exhibited significant increases in DE and DTF (p<0.05). However, DE improvements were notably superior in the HM group than in the DEXM group (p=0.024). Additionally, NIV duration was significantly reduced in the HM group compared with the DEXM group (p=0.033). There were no significant differences between groups regarding length of hospital stay or in-hospital mortality (p>0.05). The DEXM group experienced a more pronounced reduction in MAP (p=0.032), while the RR reduction was significantly greater in the HM group (p=0.003). A significant interaction between group assignment and time was observed for RR (p=0.023). Incidents of clinically significant hypotension were infrequent and comparable between groups (p>0.05). Neither group showed evidence of respiratory depression nor any detrimental impact on overall respiratory function. The findings suggest that HM may better preserve diaphragmatic function during NIV in AECOPD. Although HM was well tolerated, clinicians should remain cautious regarding potential drug accumulation and avoid prolonged administration.