Clonidine significantly reduced intraoperative blood loss compared to placebo (MD -75.15) in adult patients undergoing oral and maxillofacial surgery.
Meta-Analysis (n=1,143)
Does clonidine improve blood loss, hemodynamic stability, and surgical field quality in adult patients undergoing oral and maxillofacial surgery?
Clonidine effectively reduces blood loss and maintains hemodynamic stability compared to placebo during oral and maxillofacial surgery, though it is slightly less effective than dexmedetomidine.
Effect estimate: MD -75.15 (95% CI -96.04 to -54.25)
p-value: p=<0.00001
Background: Clonidine is an α-adrenoreceptor agonist that reduces sympathetic outflow and releases certain neurotransmitters by acting on receptors in the brain and peripheral tissues. The aim of this systematic review and meta-analysis is about the effectiveness and safety of clonidine for controlling blood loss, hemodynamic stability and surgical field quality comparing with tranxemic acid, placebo and dexmedetomidine. The randomized controlled trials that determine the effect of clonidine on blood loss, hemodynamic stability, and surgical field quality in adult patients undergoing oral and maxillofacial surgery were included. The articles included in this systematic review were searched through the electronic databases PubMed, Cochrane Library, and Google Scholar from July to September 17, 2025. The primary outcomes were controlling blood loss, hemodynamic stability, and surgical field quality. Secondary outcomes were duration of surgery and adverse events. The risk of bias was assessed by the Cochrane Collaboration tool (ROB2). Subgroup and sensitivity analysis was conducted to investigate the study of high risk of bias. Mean difference and relative risk with a 95% confidence interval were used for analysis. There were 15 articles included in the review after screening 615, with a total population of 1143. Clonidine was less blood loss than tranxemic acid (MD=40.17, 95% CI: 4.95- 75.38; p=0.03), more blood loss control than with placebo (MD=-75.15, 95% CI: -96.04-54.25; p 0.00001), and less blood loss control than with dexmedetomidine (MD=7.65, 95% CI: 1.19-14.11; p=0.02). Clonidine maintained mean arterial blood pressure than placebo (MD = -3.87, 95% CI: -6.01--1.72; p = 0.0004). Clonidine is maintained MAP in normal range than placebo when administered Pre-induction (MD=-1.88,95% CI: -3.7--0.07; p=0.04) compared with post induction (MD = -8.16.95% CI: -13.7--2.62; p=0.004). Clonidine has less poor and fair surgical field quality than placebo (RR=0.1, 95% CI: 0.02-0.42, p=0.002; RR=0.82, 95% CI: 0.67-1, p=0.05) respectively. Clonidine decreases blood loss more than placebo. Clonidine is less likely inferior to dexmedetomidine to reducing blood loss for oral and maxillofacial surgery. Clonidine maintains mean arterial blood pressure in the normal range than placebo when administered pre-induction than after induction. Clonidine maintains MAP before induction, and it is effective pre-induction as well as post-induction to maintain a mean heart rate comparable with dexmedetomidine. Clonidine is shortening the duration of surgery comparably with tranxemic acid and dexmedetomidine but more than placebo.
Hordofa et al. (Tue,) conducted a meta-analysis in Oral and maxillofacial surgery (n=1,143). Clonidine vs. Tranexamic acid, placebo, or dexmedetomidine was evaluated on Blood loss (Clonidine vs Placebo) (MD -75.15, 95% CI -96.04 to -54.25, p=<0.00001). Clonidine significantly reduced intraoperative blood loss compared to placebo (MD -75.15) in adult patients undergoing oral and maxillofacial surgery.