title: Perioperative oral pregabalin reduces chronic pain after total knee arthroplasty: a prospective, randomized, controlled trial.
abstract: BACKGROUND
  Despite the enormous success of total knee arthroplasty (TKA), chronic neuropathic pain can develop postoperatively and is both distressing and difficult to treat once established. We hypothesized that perioperative treatment with pregabalin, a chronic pain medication, would reduce the incidence of postsurgical neuropathic pain.
  
  
  METHODS
  We performed a randomized, placebo-controlled, double-blind trial of pregabalin (300 mg) administered before TKA and for 14 days after TKA (150-50 mg twice daily). Patients were screened for the presence of neuropathic pain at 3 and 6 mo postoperatively using the Leeds Assessment of Neuropathic Symptoms and Signs scale. Secondary outcomes included postsurgical recovery and rehabilitation measures, including knee range of motion, opioid consumption, postoperative pain scores, sleep disturbance, and time to discharge as well as the occurrence of postoperative systemic complications.
  
  
  RESULTS
  Of the 240 patients randomly assigned to the 2 treatment groups (120 in each), data for the primary outcome were obtained from 113 pregabalin patients and 115 placebo patients. At both 3 and 6 mo postoperatively, the incidence of neuropathic pain was less frequent in the pregabalin group (0%) compared with the placebo group (8.7% and 5.2% at 3 and 6 mo, respectively; P = 0.001 and P = 0.014). Patients receiving pregabalin also consumed less epidural opioids (P = 0.003), required less oral opioid pain medication while hospitalized (P = 0.005), and had greater active flexion over the first 30 postoperative days (P = 0.013). There were no differences in the actual recorded duration of hospitalization between the 2 groups, although time to achieve hospital discharge criteria was longer for placebo patients, 69.0 +/- 16.0 h (mean +/- SD), than that of pregabalin patients, 60.2 +/- 15.8 h (P = 0.001). Sedation (P = 0.005) and confusion (P = 0.013) were more frequent on the day of surgery and postoperative day 1 in patients receiving pregabalin.
  
  
  CONCLUSIONS
  Perioperative pregabalin administration reduces the incidence of chronic neuropathic pain after TKA, with less opioid consumption and better range of motion during the first 30 days of rehabilitation. However, in the doses tested, it is associated with a higher risk of early postoperative sedation and confusion.
authors.affiliation: Department of Anesthesiology, Rush University Medical Center, 1653 W. Congress Parkway, Chicago, IL 60612, USA. asokumar@aol.com
authors.forename: Asokumar
authors.initials: A
authors.lastname: Buvanendran
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Kroin
authors.forename: Craig J
authors.initials: CJ
authors.lastname: Della Valle
authors.forename: Maruti
authors.initials: M
authors.lastname: Kari
authors.forename: Mario
authors.initials: M
authors.lastname: Moric
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Tuman
mesh_terms: D000368:Aged; D000700:Analgesics / Q000009:adverse effects / Q000627:therapeutic use*; D000767:Anesthesia, Epidural; D019645:Arthroplasty, Replacement, Knee; D002908:Chronic Disease; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control*; D010523:Peripheral Nervous System Diseases / Q000188:drug therapy / Q000209:etiology; D000069583:Pregabalin; D011446:Prospective Studies; D016059:Range of Motion, Articular; D012890:Sleep / Q000187:drug effects; D016896:Treatment Outcome; D005680:gamma-Aminobutyric Acid / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D000700:Analgesics; D000069583:Pregabalin; D005680:gamma-Aminobutyric Acid