Dexmedetomidine infusion for emergence coughing prevention in patients undergoing an endovascular interventional procedure: A randomized dose-finding trial

Dexmedetomidine has been introduced in emergence coughing, agitation, and shivering prevention. This study aimed to investigate the optimal dose of dexmedetomidine for emergence cough prophylaxis.In this randomized, double-blinded, and prospective trial, 356 patients scheduled for an endovascular interventional procedure were randomly assigned to 0.3 (D 0.3), 0.4 (D 0.4), 0.5 (D 0.5), and 0.6 (D 0.6) μg·kg-1·h-1 dexmedetomidine rate, or saline control (C), from anesthesia induction until the end of surgery. The primary outcomes measured were cough grade and frequency. Additionally, groups were compared according to mean arterial pressure (MAP), heart rate, agitation, shivering, postoperative nausea and vomiting (PONV), extubation time, sedation scores, and postoperative first night sleep quality (secondary outcomes).A total of 351 patients were included in the analysis. The respective incidences of D 0.3, D 0.4, and D 0.5 versus C group were: 78.6%, 68.6%, 53.4% and 42.9% vs 89.7% for cough (p = 0.002, p < 0.001, and p < 0.001 between group D 0.4, D 0.5 and D 0.6 vs C, respectively); 30%, 27.1%, 20.5%, 15.7% vs 44.1% for agitation (p = 0.04, p = 0.003, and p < 0.001 between group D 0.4, D 0.5 and D 0.6 vs C, respectively); 8.6%, 7.1%, 6.8%, 5.7% vs 22.1% for shivering (p = 0.027, p = 0.013, p = 0.01, and p = 0.01 between D 0.3, D 0.4, D 0.5 and D 0.6 vs C, respectively); and 52.9%, 57.1%, 42.5%, 44.3% vs 61.8% for poor sleep quality (p = 0.02 and p = 0.04 between group D 0.5 and D 0.6 vs C, respectively). D 0.4, D 0.5 and D 0.6 showed lower MAP during extubation, compared with the C group. Also, D 0.5 and D 0.6 presented a slight delay in extubation (3.1 and 3.3 min longer than C; p = 0.002 and p < 0.001, respectively). Meanwhile, the frequency of atropine, vasopressor administration, PONV and dizziness were similar to the control.Both 0.5 and 0.6 μg·kg-1·h-1 dexmedetomidine infusion rates effectively mitigated emergence coughing with prolonged extubation time, besides sleep disturbance. D 0.4, D 0.5, and D 0.6 reduced agitation and sustained hemodynamic stability. Finally, the four doses applied were effective in shivering attenuation.