A randomized, double-blind, placebo-controlled study, with a six-month follow-up period.
The aim of this study was to test the hypothesis that a 72-hour dose of subanesthetic ketamine in this surgical procedure reduces postoperative morphine use and to assess whether there are fewer adverse effects, if postoperative recovery is faster, if there is less peri-incisional hyperalgesia, or if there is lower incidence of persistent postsurgical pain.
Tissue injury and high opioid requirements following posterior spinal fusion surgery produce central sensitization, which can in turn be associated with hyperalgesia and chronic pain. Clinical trials involving this type of procedure using subanesthetic ketamine doses have assessed pain and morphine requirements with contradictory results. The effects of prolonged subanesthetic ketamine doses on postoperative recovery, mechanical hyperalgesia, and the incidence of chronic pain are unknown.
A total of 48 pediatric patients between 10 and 18 years diagnosed with idiopathic scoliosis were randomized to receive perioperative low-dose ketamine or placebo for 72 hours. They received general anesthesia, intraoperative remifentanil, and morphine postoperatively (patient-controlled analgesia). We measured morphine consumption, pain at rest and during movement (coughing), undesirable effects, and sedation during morphine treatment. The onset of oral intake, ambulation, and hospital stay were recorded. The extent of the peri-incisional hyperalgesia was measured at 72 hours and pain controls were conducted postsurgery.
Primary endpoint results (total cumulative morphine consumption while admitted) were obtained in 44 patients. Results were 2.72 (SD 1.13) in the placebo group and 3.13 (SD 1.13) in the study group (P = 0.2903), with no significant differences. Moreover, differences were not found between the experimental group and the placebo group in the secondary endpoints analyzed.
Our findings do not support the routine combining of prolonged subanesthetic ketamine doses with opioids in posterior fusion surgery in children with idiopathic scoliosis.
Level of Evidence: 2
*Department of Anesthesia, Sant Joan de Déu Women and Children's Hospital, University of Barcelona (UB), Barcelona, Spain
†Department of Pediatric Intensive Care, Sant Joan de Déu Women and Children's Hospital, UB, Barcelona, Spain
‡Department of Orthopedics and Traumatology, Sant Joan de Déu Women and Children's Hospital, UB, Barcelona, Spain.
Address correspondence and reprint requests to Marina Perelló, MD, Department of Anesthesia, Sant Joan de Déu Hospital, University of Barcelona, Passeig Sant Joan de Déu no. 2, Esplugues de Llobregat, Barcelona, 08950 Spain. E-mail: firstname.lastname@example.org
Received 12 February, 2016
Revised 8 May, 2016
Accepted 16 June, 2016
The manuscript submitted does not contain information about medical device(s)/drug(s).
Fondo De Investigación Sanitaria del Instituto de Salud Carlos III (the main Public Research Entity funding, managing, and carrying out biomedical research in Spain) funds were received in support of this work.
No relevant financial activities outside the submitted work.