naloxone and Spinal-Fractures

Early and effective spinal immobilization, physiological support, precise radiographic analysis, and surgical intervention tailored to the specific anatomic pathology form the basis for appropriate management of spinal injury. Despite improvements in each of these areas, however, the neurologic outcome in patients with severe deficits remains problematic. Research into the prevention of adverse metabolic changes that occur in the acutely injured spinal cord may offer hope for improved outcomes.

Topics: Acute Disease; Adrenal Cortex Hormones; Craniocerebral Trauma; Female; Humans; Male; Naloxone; Spinal Cord Injuries; Spinal Fractures; Spinal Injuries; Time Factors

We present 2 cases of acute abdominal pain secondary to oral codeine that resolved after the administration of intravenous naloxone.

Topics: Abdomen, Acute; Administration, Oral; Aged; Aged, 80 and over; Analgesics, Opioid; Codeine; Humans; Injections, Intravenous; Low Back Pain; Male; Naloxone; Narcotic Antagonists; Spinal Fractures

The neural injury prevention capabilities of narcotic antagonists have previously been reported. Of the available narcotic antagonists, naloxone has been the most widely studied. Other agents with higher potency, longer half-lives, and greater specificity, however, may be more desirable for the prevention of the "secondary injury" following a primary neural insult. The relative neural injury prevention efficacies of the various narcotic antagonists is not known. The establishment of the relative effectiveness of these drugs is warranted and is of potential clinical importance. Therefore, a study was undertaken to compare the effects of the two narcotic antagonists, naloxone and nalmefene, with respect to their neuro-protective efficacy following experimental spinal cord injury (SCI) in rats. Ninety adult Sprague-Dawley rats were divided into three groups--control; naloxone (2 mg/kg i.p., 45 min following injury); and nalmefene (0.1 mg/kg i.p., 45 min following injury)--following lesioning with the ventral SCI technique. Results were evaluated by the inclined-plane technique and neurologic examination at 1 day and 1 week following injury. Histomorphological evaluation of the injured segment of spinal cord was performed following euthanasia at 1 week following injury. A significant improvement (compared with the control group) was noted in both treatment groups. This was observed with respect to neurological examination and inclined-plane scores in both treatment groups at 24 h and 1 week following lesioning (with a significance level of at least p less than 0.001; analysis of variance). The nalmefene group demonstrated a greater level of function than the naloxone group at both 24 h and 1 week following injury (not significant; p greater than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Drug Evaluation, Preclinical; Intervertebral Disc Displacement; Naloxone; Naltrexone; Nerve Crush; Paralysis; Rats; Rats, Inbred Strains; Receptors, Opioid; Receptors, Opioid, kappa; Spinal Cord Injuries; Spinal Fractures

A study of the dose-response effects of naloxone and methylprednisolone after rat ventral spinal cord injury is presented. The spinal cord injury model used herein is unique in that it results in a ventral compression of the spinal cord without the need for a prior laminectomy. This allows for a close approximation of the human clinicopathological situation. There was a statistically significant positive effect on neurological outcome with a naloxone dose of 2.5 mg/kg, whereas higher and lower doses yielded little or no influence on outcome. Methylprednisolone was observed to offer similar results. These results, however, did not achieve statistical significance. The early administration of moderately high doses (45-60 mg/kg), however, offered the best results. The responses to the treatment regimens presented here offer hope for spinal cord injury victims. The observed dose-response relationships indicate that erroneous conclusions may arise from studies using inappropriate doses of narcotic antagonists, as well as other drugs.

Topics: Animals; Disease Models, Animal; Dose-Response Relationship, Drug; Methylprednisolone; Naloxone; Paraplegia; Rats; Rats, Inbred Strains; Spinal Cord Injuries; Spinal Fractures