title: Chloroprocaine 40 mg produces shorter spinal block than articaine 40 mg in day-case knee arthroscopy patients.
abstract: BACKGROUND
  Articaine and chloroprocaine have recently gained interest as short-acting spinal anaesthetics. Based on previous work comparing articaine 60 mg with chloroprocaine 40 mg, we hypothesised that articaine 40 mg and chloroprocaine 40 mg would produce similar spinal anaesthesa regarding block onset, maximal spread, and recovery.
  
  
  METHODS
  In this randomised, double-blind study, adult patients (18-70 years, American Society of Anaesthesiologists physical status I-III, BMI < 36 kg/m(2) ) scheduled for day-case knee arthroscopy received either articaine 40 mg (20 mg/ml) (group A40, n = 16) or chloroprocaine 40 mg (20 mg/ml) (group C40, n = 18) intrathecally. Telephone interviews were performed on the first and seventh postoperative day to disclose possible side effects, e.g. transient neurological symptoms (TNS).
  
  
  RESULTS
  The groups were comparable regarding demographic data, onset and maximal spread of spinal anaesthesia, and duration of surgery. Surgery could be performed successfully under spinal anaesthesia except once in A40 (insufficient block) and once in C40 (prolonged surgery). Complete recovery was significantly slower in A40 vs. C40 for both motor block (105 (94/120) vs. 75 (71/90) min) [P < 0.001, Mann-Whitney U-test (MW-U)] and sensory block [135 (109/176) vs. 105 min (90/124)] (P < 0.02, MW-U), respectively [data are median (25th/75th percentiles)]. One patient from A40 showed mild TNS.
  
  
  CONCLUSIONS
  Both A40 and C40 provided mainly adequate spinal anaesthesia for day-case knee arthroscopy. While onset and maximal spread were comparable, the recovery from motor block was clearly faster with chloroprocaine after equivalent doses of spinal articaine and chloroprocaine.
authors.affiliation: Department of Anaesthesia, Orthopaedic Hospital Orton, Helsinki, Finland. johannes.forster@orton.fi
authors.forename: J G
authors.initials: JG
authors.lastname: Förster
authors.forename: P H
authors.initials: PH
authors.lastname: Rosenberg
authors.forename: A
authors.initials: A
authors.lastname: Harilainen
authors.forename: J
authors.initials: J
authors.lastname: Sandelin
authors.forename: M T
authors.initials: MT
authors.lastname: Pitkänen
mesh_terms: D000328:Adult; D000368:Aged; D000556:Ambulatory Surgical Procedures; D000762:Anesthesia Recovery Period; D000775:Anesthesia, Spinal / Q000379:methods*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001182:Arthroscopy; D001416:Back Pain / Q000139:chemically induced / Q000517:prevention & control; D002355:Carticaine / Q000008:administration & dosage*; D004311:Double-Blind Method; D005260:Female; D006261:Headache / Q000139:chemically induced / Q000517:prevention & control; D006801:Humans; D007278:Injections, Spinal; D007407:Interviews as Topic; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010292:Paresthesia / Q000139:chemically induced / Q000517:prevention & control; D017060:Patient Satisfaction; D011183:Postoperative Complications / Q000139:chemically induced / Q000517:prevention & control; D011343:Procaine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D011446:Prospective Studies
chemical_list: D000779:Anesthetics, Local; D011343:Procaine; C004616:chloroprocaine; D002355:Carticaine