Local anesthesia for functional endoscopic sinus surgery employing small volumes of epinephrine-containing solutions of lidocaine produces profound hypotension.

BACKGROUND: Local anesthetic containing epinephrine is commonly used in many operations for the main purpose of hemostasis. A randomized, controlled, prospective clinical trial was designed to find out hemodynamic changes after local infiltration of different concentrations and/or different dosages of epinephrine during functional endoscopic sinus surgery (FESS) under general anesthesia.

METHODS: One hundred and eight adult patients undergoing elective FESS under general anesthesia were randomly allocated into four groups. Group I received 2% lidocaine 2 ml with epinephrine (5 microg/ml); group II received 1% lidocaine 4 ml with epinephrine (2.5 microg/ml); group III received 1% lidocaine 4 ml with epinephrine (5 microg/ml); and group IV received 1% lidocaine 4 ml for local infiltration. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) were monitored continuously in the radial artery and recorded in 6 min: before infiltration (baseline), 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, and 6 min after local infiltration. The lowest blood pressure (BP) in this period was also recorded.

RESULTS: Significant hemodynamic changes, particularly a decrease in BP (P < 0.001) with a slight increase in HR (P < 0.001) at approximately 1.5 min and an increase in SBP at approximately 3 min (P < 0.01) after local infiltration, were observed in group I, group II and group III compared with the baseline, but not in group IV. No significant hemodynamic differences were observed between group I, group II and group III at the same time points (P > 0.05).

CONCLUSION: Local infiltration of low-dose epinephrine causes temporary significant hemodynamic changes particularly a marked decrease in BP during FESS under general anesthesia.