Intraoperative low-dose ketamine does not prevent a remifentanil-induced increase in morphine requirement after pediatric scoliosis surgery.

Abstract

BACKGROUND:

Remifentanil-based anesthesia is commonly used to facilitate neurophysiologic monitoring during pediatric scoliosis surgery. Acute opioid tolerance and/or hyperalgesia resulting from remifentanil-based anesthesia may involve activation of N-methyl-D-aspartate systems. We hypothesized that low-dose intraoperative infusion of the N-methyl-d-aspartate antagonist ketamine would suppress the development of tolerance and thereby decrease postoperative morphine consumption in children receiving remifentanil-based anesthesia for scoliosis surgery.

METHODS:

Thirty-four adolescents aged 12-18 yr scheduled for scoliosis surgery were randomly assigned to receive intraoperative low-dose ketamine (bolus dose of 0.5 mg/kg followed by continuous infusion of 4 microg.kg(-1).min(-1)) or an equal volume of saline during propofol/remifentanil anesthesia. Cumulative morphine consumption was assessed using a patient-controlled analgesia device for 72 h after surgery. Postoperative morphine consumption, pain scores at rest and during cough, and sedation scores were recorded by a blinded investigator every hour for the first 4 h, every 4 hours for 20 h, and then every 12 hours for 72 h.

RESULTS:

Cumulative morphine consumption at 24, 48, and 72 h after surgery did not differ significantly between groups (ketamine group: 1.57+/-0.56, 3.05+/-1.14, and 4.46+/-1.53 mg/kg; saline group: 1.60+/-0.53, 2.87+/-1.05, and 4.11+/-1.71 mg/kg, respectively). No differences in pain or sedation scores were found. The duration of anesthesia was similar in the two groups.

CONCLUSIONS:

These data do not support the use of intraoperative low-dose ketamine to prevent the development of remifentanil-induced acute opioid tolerance and/or hyperalgesia during pediatric scoliosis surgery.

• Authors: Thomas Engelhardt, Christian Zaarour, Basem Naser, Carolyne Pehora, Joost de Ruiter, Andrew Howard, Mark W Crawford
• Journal: Anesthesia and analgesia (Anesth Analg) Vol. 107 Issue 4 Pg. 1170-5 (Oct 2008) ISSN: 1526-7598 [Electronic] United States
• PMID: 18806023 (Publication Type: Journal Article, Randomized Controlled Trial)

Chemical References

• Analgesics
• Analgesics, Opioid
• Anesthetics, Intravenous
• Piperidines
• Ketamine
• Morphine
• Remifentanil

Topics

• Adolescent
• Analgesia, Patient-Controlled
• Analgesics (administration & dosage)
• Analgesics, Opioid (administration & dosage)
• Anesthetics, Intravenous (administration & dosage)
• Child
• Double-Blind Method
• Drug Tolerance
• Female
• Humans
• Intraoperative Care
• Ketamine (administration & dosage)
• Male
• Morphine (administration & dosage)
• Pain, Postoperative (drug therapy)
• Piperidines (administration & dosage)
• Remifentanil
• Scoliosis (surgery)