title: The hemodynamic effect of an intravenous antispasmodic on propofol requirements during colonoscopy: A randomized clinical trial.
abstract: OBJECTIVE
  Hemodynamic status during induction of anesthesia may modify the amount of propofol needed to induce loss of consciousness (LOC). This study was aimed to evaluate the effect of antispasmodic-induced tachycardia on the concentration of propofol at the effect-site for inducing LOC when deep sedation was executed for colonoscopy.
  
  
  METHODS
  One hundred and sixteen adult patients were randomly assigned to receive either 20 mg of the antispasmodic Buscopan intravenously (Buscopan group; n = 58) or normal saline (control group; n = 58) for colonoscopy. After administration of Buscopan, the antispasmodic or normal saline, propofol was given by means of target-controlled infusion to induce LOC. We recorded patient characteristics, hemodynamic profiles, effect-site propofol concentration upon LOC, total propofol dosage for colonoscopy, and colonoscopy outcomes.
  
  
  RESULTS
  There were no significant differences in the characteristics between the two groups. Although the patients receiving Buscopan had a higher heart rate than those of the control group (101 ± 15 beats/minute vs. 77 ± 13 beats/minute; p < 0.001), we found no significant difference between two groups in the effect-site propofol concentration for inducing LOC (3.9 ± 0.6 μg/mL vs. 3.8 ± 0.6 μg/mL; p = 0.261) nor total propofol dosage required for colonoscopy (3.2 ± 1.4 mg/kg vs. 3.1 ± 1.1 mg/kg; p = 0.698). Both groups had comparable colonoscopy outcomes, including percentage of patients completing the procedure and total procedure time.
  
  
  CONCLUSIONS
  The hemodynamic responses to intravenous Buscopan neither affected the effect-site propofol concentration needed to induce LOC, nor the total propofol dosage required for colonoscopy in this study. There is no need to modify the dosage of propofol in patients subject to Buscopan premedication in colonoscopy.
authors.affiliation: Department of Anesthesiology, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan, ROC.
authors.forename: Yun-Ying
authors.initials: YY
authors.lastname: Pao
authors.affiliation: Department of Anesthesiology, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Kaohsiung, Taiwan, ROC.
authors.forename: Kuan-Chih
authors.initials: KC
authors.lastname: Chung
authors.affiliation: Department of Anesthesiology, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan, ROC.
authors.forename: Ju-Pin
authors.initials: JP
authors.lastname: Chen
authors.affiliation: Department of Colon and Rectal Surgery, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Kaohsiung, Taiwan, ROC.
authors.forename: Ko-Chao
authors.initials: KC
authors.lastname: Lee
authors.affiliation: Department of Colon and Rectal Surgery, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Kaohsiung, Taiwan, ROC.
authors.forename: Wan-Hsiang
authors.initials: WH
authors.lastname: Hu
authors.affiliation: Department of Anesthesiology, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Kaohsiung, Taiwan, ROC.
authors.forename: Sin-Ei
authors.initials: SE
authors.lastname: Juang
authors.affiliation: Department of Anesthesiology, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Kaohsiung, Taiwan, ROC.
authors.forename: Hsiao-Feng
authors.initials: HF
authors.lastname: Lu
authors.affiliation: Department of Anesthesiology, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan, ROC.
authors.forename: Ping-Heng
authors.initials: PH
authors.lastname: Tan
authors.affiliation: Department of Anesthesiology, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan, ROC. Electronic address: ed102605@gmail.com.
authors.forename: Kuo-Chuan
authors.initials: KC
authors.lastname: Hung
mesh_terms: D061605:Administration, Intravenous; D000293:Adolescent; D000328:Adult; D000368:Aged; D018686:Anesthetics, Intravenous / Q000008:administration & dosage*; D002086:Butylscopolammonium Bromide / Q000008:administration & dosage / Q000494:pharmacology; D003113:Colonoscopy; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D010276:Parasympatholytics / Q000008:administration & dosage / Q000494:pharmacology*; D015742:Propofol / Q000008:administration & dosage* / Q000097:blood; D011446:Prospective Studies
chemical_list: D018686:Anesthetics, Intravenous; D010276:Parasympatholytics; D002086:Butylscopolammonium Bromide; D015742:Propofol
keywords: Buscopan; colonoscopy; n-butylscopolammonium bromide; propofol