Intravenous clonidine as a part of balanced anaesthesia for controlled hypotension in functional endoscopic sinus surgery: A randomised controled trial

Controlled hypotension with balanced anaesthesia minimises blood loss. This study was done to evaluate the effectiveness of intravenous clonidine as a single bolus dose to establish controlled hypotension during functional endoscopic sinus surgery (FESS). This randomised, double-blind, placebo-controlled study was done in a tertiary hospital in India. Sixty American Society of Anesthesiologists physical status I and II patients (18-65 years) undergoing FESS were randomly allocated to one of the two groups. Placebo group (group A, = 30) received sterile water whereas the clonidine group (group B, = 30) received 3μg/kg of clonidine intravenously, 30 min prior to induction of anaesthesia. The primary outcome was to achieve a target mean arterial blood pressure (MAP) of 55-65 mmHg intraoperatively. The secondary outcomes measured were requirement of additional fentanyl and metoprolol, intra-operative blood loss, surgeon's opinion on the surgical field, pain, sedation score and complications requiring treatment. Target MAP was easily achieved in clonidine group as against the placebo group ( < 0.001). Significant reduction in intra-operative blood loss ( = 0.0449), a better surgical site scoring ( = 0.02), less requirement of additional hypotensive drugs and good analgesia ( = 0.01) were seen in clonidine group. The complication rates were similar in both the groups. Clonidine is effective in achieving controlled hypotension in patients undergoing FESS. It reduces intra-operative blood loss, requirement of additional hypotensive drugs, improves the surgical field and offers good analgesia without significant side effects.