In patients who are receiving an endovascular interventional procedure and general anesthesia, the use of a dexmedetomidine infusion has been shown to mitigate the occurrence of emergence coughing. These findings were published in the European Journal of Pharmaceutical Sciences.
A randomized, double-blinded, prospective, dose-finding study was conducted at the Renmin Hospital of Wuhan University (Wuhan, China) and the Yulin No. 2 Hospital (Yulin, China). Researchers sought to determine the optimal dose of dexmedetomidine infusion for the prophylaxis of emergence coughing from the induction of anesthesia until the conclusion of the procedure in patients who were scheduled for an endovascular interventional procedure.
The primary study outcomes include cough grade and frequency. Secondary study outcomes include hemodynamic parameters; extubation respiratory rate; extubation sedation score; extubation time; postanesthesia care unit discharge time; sleep quality score on the first night following surgery; postoperative length of hospital stay; and incidence of agitation, dizziness, postoperative nausea and vomiting (PONV), shivering, and poor sleep quality.
During emergence, cough grade was evaluated using the following 4-point scale:
- 0 = no cough
- 1 (mild) = single cough
- 2 (moderate) = 1 or more nonsustained cough episode lasting for less than 5 seconds
- 3 (severe) = sustained, repetitive cough with head lift, lasting for longer than 5 seconds
Shivering score was evaluated similarly, with the following 4-point scale:
- 0 = no shivering
- 1 (mild) = facial and neck muscle fasciculations
- 2 (moderate) = more than 1 muscle group tremor
- 3 (severe) = whole-body tremor
Sedation score, agitation, PONV, and sleep quality were all assessed as well.
A total of 351 participants were randomly assigned to 1 of 5 groups. All patients’ dexmedetomidine infusion rates were set to 10 mL·h-1, with the total dexmedetomidine dosage (μg) as follows:
- group C (saline control with no dexmedetomidine dosage; n=68)
- group D 0.3 μg (1.5 x weight [kg]; n=70)
- group D 0.4 μg (2 x weight [kg]; n=70)
- group D 0.5 μg (2.5 x weight [kg]; n=73)
- group D 0.6 μg (3 x weight [kg]; n=70)
Results of the study show that for cough, the respective incidences in groups D 0.3, D 0.4, D 0.5, and D 0.6 vs group C are 78.6%, 68.6%, 53.4%, and 42.9% vs 89.7% (P =.002, P <.001, and P <.001 among groups D 0.4, D 0.5, and D 0.6 vs group C, respectively). For agitation, the respective rates are 30.0%, 27.1%, 20.5%, and 15.7% vs 44.1% (P=.04, P =.003, and P <.001 among groups D 0.4, D 0.5, and D 0.6 vs group C, respectively).
For shivering, the respective incidences in groups D 0.3, D 0.4, D 0.5, and D 0.6 vs group C are 8.6%, 7.1%, 6.8%, and 5.7% vs 22.1% (P =.027, P =.013, P =.01, and P =.01 among groups D 0.3, D 0.4, D 0.5, and D 0.6 vs group C, respectively). For poor sleep quality, the respective rates are 52.9%, 57.1%, 42.5%, 44.3% vs 61.8% (P =.02 and P =.04 between groups D 0.5 and D 0.6 vs group C, respectively).
Groups D 0.4, D 0.5, and D 0.6 show lower mean arterial pressure (MAP), as well as MAP during extubation, compared with group C. Further, patients in groups D 0.5 and D 0.6 exhibit a slight delay in extubation (3.1 minutes and 3.3 minutes longer than group C; P =.002 and P <.001, respectively).
Based on patients’ hemodynamic changes, limitations of the study include the fact that the attending anesthesiologist who evaluated the cough grade may have been blinded to a participant’s group assignment. Further, since a presurgical sleep assessment was not performed, the possible deviation introduced by inconsistent baseline sleep quality could not be prevented.
Both the 0.5 and 0.6 μg·kg-1·h-1 dexmedetomidine infusion rates were effective in decreasing cough grade, as well as the occurrences of sleep disturbances and moderate to severe cough, but prolonged extubation time. “0.6 μg·kg-1·h-1 [dexmedetomidine] infusion rates were identified as most effective to control cough overall prevalence, agitation, sleep disturbance, shivering, and hemodynamic stability,” the study authors wrote.
Wang W, Huo P, Wang E, et al. Dexmedetomidine infusion for emergence coughing prevention in patients undergoing an endovascular interventional procedure: a randomized dose-finding trial. Eur J Pharm Sci. Published online July 8, 2022. doi:10.1016/j.ejps.2022.106230