title: Effects of adding ketamine to fentanyl plus acetaminophen on postoperative pain by patient controlled analgesia in abdominal surgery.
abstract: BACKGROUND
  Postoperative pain is one of the most important complications encountered after surgery. A number of options are available for treating pain following surgery. One of those options is the use of intravenous patient-controlled analgesia (PCA). Ketamine is an anesthetic drug relieving pain with its NMDA receptor antagonistic effect.
  
  
  OBJECTIVE
  This study is aiming at better pain management after abdominal surgery; the effects of adding ketamine to intravenous fentanyl plus acetaminophen PCA were evaluated.
  
  
  METHODS
  In a double-blind randomized clinical trial 100 patients, ASA I or II, 20 - 60 years old were divided into two groups. These patients were abdominal surgery candidates. In order to control postoperative pain in the control group an IV patient-control analgesia (PCA) containing fentanyl 10 μg/mL plus acetaminophen 10 mg/mL was instructed to be used for the patients, but the patients in ketamine group received ketamine 0.5 mg/mL plus control group PCA content. During the first 48 hours after surgery, ketamine patients were evaluated every 8 hours (at rest, while moving and coughing) to determine their pain scores using VAS scale, sedation score, additional analgesics, nausea and vomiting.
  
  
  RESULTS
  There were no significant demographic differences between two groups. Pain scores (at rest, while moving and coughing) during the first 48 hours were not significantly different between two groups (P values = 0.361, 0.367 and 0.204, respectively). Nausea scores were significantly lower in the ketamine group (P = 0.026).
  
  
  CONCLUSIONS
  The addition of ketamine to intravenous fentanyl plus acetaminophen PCA had not extra effects in relieving post abdominal surgery pain.
authors.affiliation: Department of Anesthesiology, Rasoul Akram Medical Center, Iran University of Medical sciences, Tehran, Iran.
authors.forename: Farnad
authors.initials: F
authors.lastname: Imani
authors.affiliation: Department of Anesthesiology, Rasoul Akram Medical Center, Iran University of Medical sciences, Tehran, Iran.
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Faiz
authors.affiliation: Department of Anesthesiology, Rasoul Akram Medical Center, Iran University of Medical sciences, Tehran, Iran.
authors.forename: Minow
authors.initials: M
authors.lastname: Sedaghat
authors.affiliation: Department of Anesthesiology, Rasoul Akram Medical Center, Iran University of Medical sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Hajiashrafi
keywords: Abdomen; Acetaminophen; Fentanyl; Ketamine; Pain; Postoperative; Surgical Abdomen