The purpose of the study was to compare the efficacy of dexmedetomidine (DEX) and clonidine (CLON) infusion to produce hypotensive anesthesia in patients undergoing orthognathic surgery.

The investigators designed a randomized controlled trial on patients undergoing orthognathic surgery. Patients were randomized into 2 groups (DEX and CLON group). The DEX group patients received loading dose of 1ug/kg DEX over 10 minutes followed by 0.2 to 0. 5ug/kg/h as maintenance dose. Similarly, CLON group patients received 3ug/kg loading dose followed by maintenance dose of 0.3 to 2ug/kg/h. Primary objectives were to compare the quality of surgical field, duration of surgery, amount of blood loss and secondary objectives were to compare total and rescue analgesia used, need for blood transfusion and associated adverse effects. The p-value of <0.05 was taken significant at confidence interval of 95%.

The study sample included 30 patients (15 in each group), (m:f=1:1.1) requiring orthognathic surgery. Single jaw cases were 11 (DEX:CLON= 4:7) and bijaw cases were 19 (DEX:CLON=11:8) in number. There was no statistically insignificant difference in quality of surgical field between 2 groups (p=0.15). Duration of surgery was 293.33±58.75 and 247±70.45 min in DEX and CLON group, respectively (p=0.06). Blood loss was more in DEX group (316.61±147.19 ml) than CLON group (263.33±112.54 ml), (p=0.71). Total drug used (p=0.33) and rescue analgesia (p=0.25) was less in DEX group. Adverse effects were more in CLON than DEX group.

The results of the present study showed no significant difference between 2 groups for any parameter. It can be concluded that both dexmedetomidine and clonidine are effective and safe in achieving controlled hypotension and safe operative field visibility.