Epidural phenylephrine attenuates hypotension induced by alkalinized lidocaine epidural anesthesia

In this double-blinded, randomized study, we examined the hemodynamic effec ts of lumbar epidural injection of alkalinized lidocaine with phenylephrine in 81 patients undergoing inguinal herniorrhaphy. Patients assigned to fou r equal groups received 20 mL of alkalinized Lidocaine (17 mL of 2% lidocai ne + 3 mL of 7% sodium bicarbonate) with one of four doses of phenylephrine : 0 (Group 1), 50 (Group 2), 100 (Group 3), or 200 mu g (Group 4) injected via a lumbar epidural catheter. Blood pressure, heart rate, and skin temper ature on the foot were recorded every 5 min for 1 h after injection and wer e compared among groups. Hypotension was defined as mean arterial pressure < 80% of baseline. The incidence of hypotension was 45%, 55%, 35%, and 15% in Groups 1-4, respectively. Patients in Group 4 showed the smallest reduct ion in blood pressure compared with Groups 1 and 2 tone-sided Fisher's exac t test, P < 0.05). We conclude that the 200-mu g dose of epidural phenyleph rine (1:100,000 concentration) reduced the incidence of hypotension after e pidural anesthesia with alkalinized lidocaine. Implications: Hypotension af ter epidural anesthesia is common in general clinical practice. Phenylephri ne administered epidurally in combination with alkalinized lidocaine may re duce the incidence of hypotension.