Effect of ketamine, an NMDA receptor inhibitor, in acute and chronic orofacial pain

Abstract

We examined the analgesic effect of racemic ketamine and its 2 enantiomers in 16 female patients (age: 20-29 years) suffering acute pain after oral surgery and in 7 female patients (age: 42-79 years) suffering chronic neuropathic orofacial pain. All 3 forms of ketamine consistently relieved postoperative pain, (S)-ketamine being 4 times more potent than (R)-ketamine. The analgesic effect was maximal 5 min after i.m. injection and lasted for about 30 min. The 7 patients with neuropathic pain received ketamine at one or several occasions. Four patients (age: 54-79 years) who had suffered pain for more than 5 years did not experience an analgesic effect, whereas 3 patients (age: 42-53 years) who had suffered pain for less than 3 years reported pain relief lasting from 24 h to 3 days. The individual type of response did not depend on the form of ketamine used. The mental side effects were qualitatively similar for the 3 forms of ketamine. Relative to the analgesic effect (S)-ketamine caused more disturbing side effects than did (R)-ketamine. The mean serum concentration of each form of ketamine at the time of maximal effect was close to the approximate Kd value for PCP site occupancy by that particular form. This is in concert with the hypothesis that the effect of ketamine on acute nociceptive pain is due to N-methyl-D-aspartate (NMDA) receptor inhibition and adds to the evidence that NMDA receptors are important for the perception of acute, nociceptive pain in humans.(ABSTRACT TRUNCATED AT 250 WORDS)

Pre-Emptive Analgesia with Ketamine for Relief of Postoperative Pain After Surgical Removal of Impacted Mandibular Third Molars

“…In various studies done by Satilmiş et al [32], Garip et al [33], Gupta et al [36] ketamine has shown to reduce postoperative pain and swelling in patients undergoing surgical removal of third molars and also provide a comfortable procedure for the surgeon and patient. But in contrast Lebrun et al [35] concluded that there was no benefit to pre-emptive administration of ketamine 300 lg/ kg iv whether administered pre-or postoperatively after assessing the effect on 84 patients scheduled for third molar surgical removal.…”

“…Recently ketamine has been used in oral and maxillofacial surgical practice as well [14,[32][33][34][35][36].…”

“…In oral and maxillofacial surgery, Mathisen et al [33] examined analgesic effect of racemic ketamine and its 2 enantiomers in 16 female patients who had their 3rd molar teeth surgically removed on prophylactic indications, under local anaesthesia. The patients received ketamine by intramuscular injection and all three forms of ketamine consistently relieved postoperative pain.…”

Total intravenous anaesthesia with propofol-racemic ketamine and propofol-S-ketamine: a comparative study and haemodynamic evaluation in dogs undergoing ovariohysterectomy

“…In man, S(+)Ketamine has an anaesthetic-analgesic effect two to four times greater than racemic ketamine (White et al 1985, Mathisen et al 1995, Lauretti et al 2000, and its hyptonic effect is more potent than that of the R(-) isomer (Terra et al 1999), witch allows the use of lower doses of S(+) ketamine when compared to racemic ketamine. Rossetti et al (2008) observed in stallions undergoing castration, a higher analgesic effect of S(+)-ketamine, which was represented by a more stable physiologic parameters during the procedure and also a lower anesthetic requirement.…”

“…In man, S(+)Ketamine has an anaesthetic-analgesic effect two to four times greater than racemic ketamine (White et al 1985;Mathisen et al 1995;Lauretti et al 2000), and its hyptonic effect is more potent than that of the R(-) isomer (Terra et al 1999), allowing the use of lower doses of S(+) ketamine compared to racemic ketamine.…”