Ultra-low-dose Naloxone as an Adjuvant to Patient Controlled Analgesia (PCA) With Morphine for Postoperative Pain Relief Following Lumber Discectomy: A Double-blind, Randomized, Placebo-controlled Trial.
BACKGROUND
Lumbar discectomy is one of the most commonly performed neurosurgical procedures. Many patients experience postoperative pain after lumbar discectomy. This study evaluated the effect of ultra-low-dose naloxone infusion on pain intensity after lumbar discectomy in individuals receiving patient-controlled analgesia (PCA) with morphine.


METHODS
In a double-blind, randomized, controlled trial, a total of 80 patients scheduled for open discectomy was randomly assigned to receive naloxone (group N) or placebo (group P). After surgery, all patients were connected to a morphine PCA pump. Both groups received 500 mL of normal saline using a continuous infusion pump through a separate intravenous line for 24 hours. However, group N received a total dose of 0.25 μg/kg/h naloxone, which was added to the normal saline infusion. All patients were asked to grade the intensity of their pain, severity of nausea, vomiting, and pruritus on a 0 to 10 visual analog scale before being discharged from the postanesthesia care unit and at 1, 6, 12, and 24 hours postoperatively.


RESULTS
It was observed that both groups had a statistically significant (P<0.01) time trend difference for pain, nausea, and pruritus scores. A significant difference was found between the 2 groups in terms of intensity of pain, nausea, and pruritus, with the naloxone group experiencing a lower level in comparison with the placebo group. Moreover, the median (interquartile range) of morphine consumption after surgery for patients who received naloxone was 26 (24.25 to 28) mg, which is significantly (P<0.001) lower than for the placebo group, which had a median (interquartile range) of 34 (32 to 36) mg.


CONCLUSIONS
It is concluded that infusion of ultra-low-dose naloxone (0.25 μg/kg/h) along with morphine PCA can significantly reduce pain intensity, morphine consumption, and opioid-induced nausea and pruritus after lumbar discectomy.
Departments of Anesthesiology.
Abolfazl
A
Firouzian
Departments of Anesthesiology.
Afshin
A
Gholipour Baradari
Epidemiology.
Abbas
A
Alipour
Department of Medical-Surgical Nursing, School of Nursing and Midwifery, Mashhad University of Medical Sciences, Mashhad, Iran.|Medical-Surgical Nursing, Faculty of Nursing and Midwifery, Mazandaran University of Medical Sciences, Sari.
Amir
A
Emami Zeydi
Departments of Anesthesiology.
Alieh
A
Zamani Kiasari
Departments of Anesthesiology.
Seyed Abdollah
SA
Emadi
Departments of Anesthesiology.
Behrooz
B
Kheradmand
Neurosurgery, Faculty of Medicine.
Kaveh
K
Hadadi
D000328:Adult; D000368:Aged; D016058:Analgesia, Patient-Controlled / Q000379:methods*; D000701:Analgesics, Opioid / Q000009:adverse effects / Q000627:therapeutic use*; D017586:Diskectomy / Q000379:methods*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D007405:Intervertebral Disc Displacement / Q000601:surgery; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000009:adverse effects / Q000627:therapeutic use*; D009270:Naloxone / Q000008:administration & dosage / Q000627:therapeutic use*; D009292:Narcotic Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D020250:Postoperative Nausea and Vomiting / Q000188:drug therapy / Q000453:epidemiology; D011537:Pruritus / Q000139:chemically induced / Q000188:drug therapy / Q000453:epidemiology
D000701:Analgesics, Opioid; D009292:Narcotic Antagonists; D009270:Naloxone; D009020:Morphine