Prophylactic dexmedetomidine use did not decrease the incidence of delirium in patients undergoing cardiac surgery: A meta-analysis

Objective The benefits of prophylactic dexmedetomidine use in patients undergoing cardiac surgery remain controversial. The aim of this meta-analysis was to investigate the short-term clinical outcomes of dexmedetomidine use versus non-dexmedetomidine use. Methods Systematic searches using PubMed, Embase, and the Cochrane Library were carried out for English articles published from inception to 23 September 2021. This was followed by a meta-analysis investigating delirium, the length of delirium, mortality, bradycardia, hypotension, the length of intensive care unit (ICU) and hospital stay, and the duration of mechanical ventilation. Results Ten randomized controlled trials (RCTs) totaling 2550 patients were included. In the dexmedetomidine group incidence of delirium was 13.5%, compared with 16.1% in the control group. The risk ratio (RR) for the comparison was 0.69 (95% CI, 0.47 – 1.00; p = .052). In addition, there were no differences in mortality (RR, 0.56; 95% CI, 0.27 – 1.14; p = .109), the incidence of bradycardia (RR, 1.20; 95% CI, 0.91 – 1.57; p = .201), the incidence of hypotension (RR, 0.90; 95% CI, 0.57 – 1.44; p = .674), and the length of delirium mean difference (MD, −0.99; 95% CI, −2.20 to 0.21; p = .106). However, prophylactic dexmedetomidine use significantly reduced the duration of mechanical ventilation (MD, −2.03; 95% CI, −3.35 to −0.70; p = .003), length of ICU stay (MD, −3.17; 95% CI, −5.10 to −1.24; p = .001), and length of hospital stay (MD, −1.76; 95% CI, −2.88 to −0.66; p = .002). Conclusions Prophylactic dexmedetomidine use did not decrease the incidence of delirium in patients undergoing cardiac surgery, but significantly reduced the duration of mechanical ventilation, length of ICU stay, and length of hospital stay.