title: The effect of a continuous infusion of low-dose esmolol on the requirement for remifentanil during laparoscopic gynecologic surgery.
abstract: OBJECTIVE
  To investigate whether a continuous infusion of low-dose esmolol results in an opioid-sparing effect during surgery.
  
  
  METHODS
  Randomized, double-blinded, placebo-controlled clinical comparison study.
  
  
  METHODS
  Operating room of a university hospital.
  
  
  METHODS
  56 ASA physical status 1 and 2 patients, aged 20 to 60 years, undergoing laparoscopic gynecologic surgery of less than two hours' duration.
  
  
  METHODS
  The esmolol group (n = 28) received a 0.5 mg/kg loading dose of esmolol followed by an infusion of esmolol 30 μg/kg/min; the saline group (n = 28) received equivalent volumes of normal saline.
  
  
  METHODS
  The effect-site concentration of remifentanil (ng/mL) to maintain adequate anesthetic depth before infusion of the study drug (before-concentration) was measured. During infusion of study drug, the effect-site concentration of remifentanil was adjusted every 5 minutes to maintain systolic blood pressure within 15% of baseline and a Bispectral Index value between 50-60. The average of these adjusted concentrations (after-concentration) was measured and compared to the before-concentration. The quality of postoperative recovery was assessed.
  
  
  RESULTS
  In the esmolol group, the after-concentration of remifentanil was decreased by 33.3% compared with the before-concentration. The total dose of remifentanil infused was also lower in the esmolol group (0.09 ± 0.1 vs 0.14 ± 0.03 μg/kg/min; P = 0.031). The esmolol group had lower scores on a pain numerical rating scale and required less fentanyl in the Postanesthesia Care Unit.
  
  
  CONCLUSIONS
  Intraoperative esmolol infusion decreases both the requirement for remifentanil and postoperative administration of rescue analgesics.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Banpo-dong 504, Seoul, Korea.
authors.forename: Won-Jung
authors.initials: WJ
authors.lastname: Hwang
authors.forename: Young-Eun
authors.initials: YE
authors.lastname: Moon
authors.forename: Sun-Jin
authors.initials: SJ
authors.lastname: Cho
authors.forename: Jaemin
authors.initials: J
authors.lastname: Lee
mesh_terms: D058671:Adrenergic beta-1 Receptor Antagonists / Q000008:administration & dosage*; D000328:Adult; D000701:Analgesics, Opioid / Q000008:administration & dosage; D018686:Anesthetics, Intravenous / Q000008:administration & dosage*; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D013509:Gynecologic Surgical Procedures; D006801:Humans; D007262:Infusions, Intravenous; D010535:Laparoscopy; D008875:Middle Aged; D010149:Postoperative Pain / Q000517:prevention & control; D010880:Piperidines / Q000008:administration & dosage*; D011182:Postoperative Care / Q000379:methods; D011412:Propanolamines / Q000008:administration & dosage*; D000077208:Remifentanil; D055815:Young Adult
chemical_list: D058671:Adrenergic beta-1 Receptor Antagonists; D000701:Analgesics, Opioid; D018686:Anesthetics, Intravenous; D010880:Piperidines; D011412:Propanolamines; C036604:esmolol; D000077208:Remifentanil