Comparative Study between Magnesium Sulfate and Lidocaine for Controlled Hypotension during Functional Endoscopic Sinus Surgery: A Randomized Controlled Study.

BACKGROUND

Intraoperative bleeding impairs surgical field visibility during functional endoscopic sinus surgery (FESS); several methods have been used to decrease blood loss and improve surgical field, one of them is usage of hypotensive anesthetic agents.

AIM

We intended to compare magnesium sulfate with lidocaine, regarding their efficiency in inducing controlled hypotension and providing a better surgical field exposure during FESS and the influence of their usage on extubation time.

SETTINGS AND DESIGN

This study design was a prospective randomized controlled double-blinded clinical study.

PATIENTS AND METHODS

Eighty adult patients with patients' physical status ASA Classes I and II, aged 20-50 years scheduled for FESS were randomly divided into two study groups; each group contains 40 patients: Group L received lidocaine 2 mg/kg/h with maximum of 200 mg/h starting at induction of anesthesia and continuing until the end of surgery and Group M received an iv bolus of magnesium sulfate 50mg/kg in a total of 100ml saline over 10 min followed by infusion of 15mg/kg/h until the end of surgery; patients were observed for the quality of the surgical field, blood loss, and extubation time.

STATISTICAL ANALYSIS USED

Student's -test or Mann-Whitney's U, Chi-square, or Fisher's exact tests were used.

RESULTS

Group L showed a significant decrease in blood loss ( = 0.01), better surgical field clarity ( = 0.002), and shorter extubation time ( = 0.001) than Group M, but there was no statistically significant difference between the two study groups as regards hemodynamics.

CONCLUSION

We concluded that both magnesium sulfate and lidocaine successfully induced controlled hypotension in patients undergoing FEES, but lidocaine provided better surgical field clarity and shorter extubation time.