Evaluation of Oral Clonidine Premedication on Intraoperative Blood Loss and Bleeding Severity Score in Functional Endoscopic Sinus Surgery – A Prospective Placebo Controlled Study

Background: Bleeding during functional endoscopic sinus surgery (FESS) remains a challenge for both surgeons and anaesthesiologists despite several modalities available for improving the surgical field. This study was conducted to evaluate the effect of oral clonidine premedication on blood loss and the quality of the surgical field in FESS.
Methods: This prospective placebo controlled trial was performed on 120 patients (ASA I, ASA II). Patients undergoing endoscopic sinus surgery for chronic sinusitis and nasal polyposis were randomly allocated to receive either oral clonidine 0.005mg/kg or identical-looking placebo tablets 90 min before arrival at the operating room. During general anaesthesia, the hemodynamic endpoint of the anaesthetic management was maintenance of hypotension (Mean Arterial Presure) at ≤ 65 mmHg for producing a bloodless surgical field. The control of MAP was attained with inspired concentration increments of halothane up to maximum of 1.5 vol % as needed. Intraoperative bleeding was assessed on a six – point scale from 0 (= no bleeding) to 5 (= severe bleeding). Data were compared with chisquare test, fisher's exact test and Student t-test.
Results: There was less bleeding volume in the clonidine group (mean±SD) than in the placebo group (140.7±65.4 Vs 199.2±104.4, P<0.05). Frequency of bleeding severity scores 3 and 4 (troublesome with repeated suction) were lower in the clonidine group than in the placebo group (13.3 Vs 33.3%, P< 0.05). ). Accordingly, the surgeon was more satisfied with the surgical field in the clonidine group than with that in the placebo group.
Conclusion: In conclusion, premedication with oral clonidine can effectively reduce bleeding during endoscopic sinus surgery.