The Value of Systemic Ketamine for Preemptive Analgesia in a Rat Model for ostoperative Pain / 대한마취과학회지

BACKGROUND: Pretreatment of systemic ketamine reduced pain behaviors in some animal models with persistent pain. However, a clinically relevant preemptive analgeisic effect of systemic ketamine is controversial. The purpose of this study was to examine the preemptive effect of systemic ketamine in rats undergoing a plantar incision. METHODS: Ketamine (10, 30, or 100 mg/kg) or a saline vehicle was administered subcutaneously 30 minutes before an incision was made. Withdrawal thresholds to calibrated von Frey filaments adjacent to the wound were measured before incision and from 2 hours to postoperative 6 days after incision. To evaluate the effectiveness of an extension of antinociceptive treatment into the initial postoperative period, 30 mg/kg ketamine or a saline vehicle 30 minutes before an incision was made was administered subcutaneously followed by injection of 5 more of the same drug or vehicle every 1 hour. The development of pain behavior was also evaluated before incision and from 30 minutes after last drug injection to postoperative 6 days. RESULTS: In saline vehicle-treated rats, mechanical hyperalgesia was persistent through day 1 after surgery and then gradually returned to the preincisional value. Thirty mg/kg ketamine increased the withdrawal threshold at 2 hours. One hundred mg/kg ketamine caused a motor block at 2 hours and increased the withdrawal threshold at 2.5 and 3 hours. A repeated injection of 30 mg/kg ketamine caused a motor block during the first 2 hours, and reduced hyperalgesia at 3 and 4 hours after the last drug injection. However, there were no significant differences in withdrawal thresholds among the groups at all subsequent times. CONCLUSIONS: Antinociceptive treatment of systemic ketamine covers the period of surgery and the initial postoperative period by reducing early pain behavior, but had no impact on subsequent measures of hyperalgesia. Therefore, a preemptive effect of systemic ketamine in postoperative pain seems unlikely.

The Analgesic Effect of Combined Infusions of Morphine and Ketamine Using an Intravenous PCA after a Cesarean Section / 대한마취과학회지

BACKGROUND: Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, is known to have analgesic properties in subanesthetic doses and has been used as an analgesic in the postoperative period by variable routes. The effect of adding ketamine to analgesia using intravenous PCA morphine was evaluated in 90 women after cesarean section. METHODS: Ninety parturients were randomly allocated to three groups and each group had 30 women. The parturients in group 1 were given analgesics of morphine only, group 2 were given analgesics of the 2 : 1 mixture of morphine and ketamine, and group 3 were given analgesics of the 1 : 1 mixture of morphine and ketamine. We evaluated the analgesic requirement, numerical rating pain score, side effects and patient's satisfaction. RESULTS: The morphine requirement in group 3 was significantly lower than that in groups 1 and 2 at 3, 6, 12, 24 and 48 hours postoperatively. The pain score in group 2 was lower than that in group 1 at 3 and 6 hours and the pain score in group 3 was lowest of all groups at 3 and 6 hours. The incidence of dizziness was higher in group 3 than in groups 1 or 2. CONCLUSIONS: We concluded that adding ketamine with morphine in using an intravenous PCA can decrease analgesic requirements and improve analgesic property.

The Effects of Preincisional and Postincisional Low-Dose Ketamine in Addition to General Anesthesia on the Patient Controlled Analgesia for Postoperative Pain / 대한마취과학회지

BACKGROUND: Ketamine, a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, is known to inhibit "wind-up" and hence central hyperexcitability of dorsal horn neurons. However the results of clinical studies for its preemptive analgesic effect are controversial. The object of this study is to evaluate the effects of preincisional and postincisional low-dose ketamine on postoperative pain. METHODS: In a randomized, double-blind study, postoperative pain was assessed in 60 patients undergoing spinal fusion with general anesthesia who were allocated to three groups. Twenty patients were received 0.15 mg/kg of ketamine and the same volume of saline 5 min before and 15 min after surgical incision, respectively (group I). Patients in group II received 0.15 mg/kg of ketamine and the same volume of saline 15 min after and 5 min before surgical incision, respectively (n = 20), and in control group, patients received saline 5 min before and 15 min after surgical incision (n = 20). IV patient-controlled analgesia (PCA) with a morphine-ketorolac mixture was started in all patients at skin closure. Visual numerical scale (VNS) pain score, total analgesic consumption, and side effects were recorded at 1, 3, 6, 12, 24 and 48 h postoperatively. RESULTS: No significant intergroup differences were seen in the VNS pain scores, total analgesic consumption and incidence of side effects at 1, 3, 6, 12, 24 and 48 h postoperatively. CONCLUSIONS: This result indicates that postoperative pain cannot be decreased when ketamine in low doses is added to general anesthesia before and after surgical stimulation.

The Comparison of Epidural Morphine and Epidural Morphine-Ketamine for Postoperative Pain Relief after Subtotal Gastrectomy / 대한마취과학회지

BACKGROUND: Epidural narcotics are now widely used for postoperative pain relief, but their side effects are problematic. Thus, this study was undertaken to evaluate the analgesic effects and to minimize the side effects of the combination of epidural morphine and ketamine versus epidural morphine alone in pateints with postoperative pain. METHODS: The value of using a combined infusion of morphine with a variable dose of ketamine for postoperative analgesia following subtotal gastrectomy was assessed in a double-blind randomised study of 30 patients. Three groups of 10 patients received an infusion of morphine at 2 mg/day, either alone, or combined with ketamine at a rate of 0.4 or 0.6 mg/kg/day. RESULTS: Postoperative anlagesia, sedation, and side effects were not statistically significantly different between groups I and II. Postoperative sedation, and side effects were not statistically significantly different between groups I and III. VAS of group III at 1-2 h was lower than in group I. CONCLUSION: The addition of ketamine to a continuous infusion of morphine dose not significantly improve postoperative analgesia. In addition, increasing the dose of ketamine does not significantly improve postoperative analgesia, Nor does it increase sedation, or side effects.

Preemptive Effect of Preoperative Intravenous Ketamine / 대한마취과학회지

BACKGROUND: Ketamine is an N-methyl-D-aspartate (NMDA) receptor antagonist with analgesic properties that may be important in the modulation of central sensitization to nociceptive stimulation. The aim of the present study was to determine if preemptive administration of systemic ketamine decreases postoperative pain when compared with postwound closure administration of ketamine. METHODS: Forty-five patients scheduled for total abdominal hysterectomy were divided into three groups. Before surgical incision, 0.5 mg/kg ketamine was administered alone (group 1, n=15) or followed by ketamine infusion of 10 microgram/kg/min until abdominal closure (group 2, n=15). The other patients were given 0.5 mg/kg of ketamine immediately after abdominal closure (group 3, n=15). Patient-controlled analgesia (PCA) using butorphanol and ketorolac was started after the awakening of patients. Postoperative pain and total infusion doses of the PCA drug were assessed during the 48 hr. period after awakening. RESULTS: The total infusion dose of the PCA drug was significantly lower in group 1 and 2. No significant intergroup differences were seen in the pain score, sedation score and incidences of side effects. CONCLUSIONS: Preoperative and intraoperative administration of ketamine is more effective in reducing postoperative analgesic requirements than it is when given after operation.

Pain Management for the Cancer Pain by Continuous Intravenous Infusion of Ketamine: A case report / 대한마취과학회지

Although a major portion of terminal cancer patients have appealed pain, the management of their pains is not easy. We managed two terminal cancer patients. One subject was a 86-year-old female who, after pronounced lung cancer, suffered from shoulder pain. The other was a 28-year-old female who, after being subject to pronounced acute lymphocytic leukemia, suffered from hip joint and thigh pain. In our practice, their pain, which had not been controlled by various other sophisticated management strategies, was effectively alleviated by a continuous intravenous infusion of ketamine, a N-methyl-D-aspartic acid receptor antagonist. The initial dose was administered intramuscularly by injecting 10 mg. of ketamine into the patients and then an intravenous infusion was administered at the rate of 0.06 mg/kg/hr. After the continuous infusion of ketamine was initiated, the VAS decreased, respectively, from 9 and 10 to 4 and 3, without considerable side effects. In conclusion, intravenous infusion at the level of sub-anesthetic dose of ketamine is a good management to control totally bed-conditioned and intactable cancer pain.

The Effects of Preoperative or Postperitoneal Closure Epidural Ketamine on Epidural Anesthesia and Analgesia for Obstetric Patients / 대한마취과학회지

BACKGROUND: The NMDA receptor mediates wind-up and long-term potentiation in the responses of cells to prolonged stimuli; thus we postulated that the induction and maintenance of sensitization would be affected by the timing of epidural ketamine administration under epidural anesthesia. METHODS: Sixty patients undergoing elective cesarian section were randomly and equally assigned to one of three groups. 20 ml of 2% lidocaine and 2 mg morphine with epinephrine was injected to all patients epidurally through an indwelling catheter inserted at the L2-3 interspace. Before surgical incision, the patients in group 1 were given 3 ml saline, while the patients in group 2 were given 30 mg ketamine. In group 3, patients were injected with 30 mg ketamine after peritoneal closure. An additional 2 mg morphine was injected into all patients 24 h after surgery. The analgesic effects were assessed and side effects were also evaluated. RESULTS: VAS of group 3 at 3 24 h was lower than in the group 1, and at 6 24 h it was lower than in the group 2. The number of patients using additional analgesics in group 3 was lower than in the other groups. The incidence of nausea and vomiting was higher in the group 1 than in the other groups, but dizzness was higher in the groups 2 and 3 than in the control group. CONCLUSIONS: Preoperative administration of epidural ketamine is less effective in reducing postoperative pain than when given after peritoneal closure, especially under epidural anesthesia with local anesthetics.

The Effects of Preoperative or Postperitoneal Closure Epidural Ketamine on Epidural Anesthesia and Analgesia for Obstetric Patients / 대한마취과학회지

BACKGROUND: The NMDA receptor mediates wind-up and long-term potentiation in the responses of cells to prolonged stimuli; thus we postulated that the induction and maintenance of sensitization would be affected by the timing of epidural ketamine administration under epidural anesthesia. METHODS: Sixty patients undergoing elective cesarian section were randomly and equally assigned to one of three groups. 20 ml of 2% lidocaine and 2 mg morphine with epinephrine was injected to all patients epidurally through an indwelling catheter inserted at the L2-3 interspace. Before surgical incision, the patients in group 1 were given 3 ml saline, while the patients in group 2 were given 30 mg ketamine. In group 3, patients were injected with 30 mg ketamine after peritoneal closure. An additional 2 mg morphine was injected into all patients 24 h after surgery. The analgesic effects were assessed and side effects were also evaluated. RESULTS: VAS of group 3 at 3 24 h was lower than in the group 1, and at 6 24 h it was lower than in the group 2. The number of patients using additional analgesics in group 3 was lower than in the other groups. The incidence of nausea and vomiting was higher in the group 1 than in the other groups, but dizzness was higher in the groups 2 and 3 than in the control group. CONCLUSIONS: Preoperative administration of epidural ketamine is less effective in reducing postoperative pain than when given after peritoneal closure, especially under epidural anesthesia with local anesthetics.

Effects of Ketamine and Clonidine for Caudal Analgesia Produced by Bupivacaine in Pediatric Ambulatory Surgery / 대한마취과학회지

BACKGROUND: Caudal block has proved to be a satisfactory method of providing perioperative analgesia for pediatric surgery in inguinal and perineal areas. This study was designed to evaluate the effects of ketamine or clonidine as an adjunctive of caudal block produced by bupivacaine. METHODS: One hundred ninety five children aged 1~10 years, undergoing surgery in inguinal and perineal areas as ambulatory cases, were randomly allocated to one of four groups after the induction of general anesthesia; 0.25 % bupivacaine 1 ml/kg(group B), 0.25 % bupivacaine 1 ml/kg with ketamine 0.5 mg/kg(group K), 0.25 % bupivacaine 1 ml/kg with clonidine 1 microgram/kg(group C), and local infiltration group(group L). Postoperative pain was assessed using an objective pain scale and the incidence of side effects, such as urinary retention and nausea/vomiting was observed after surgery. RESULTS: In the group B and L, OPS score was higher and analgesics were more frequently administered than group K and C at the recovery room and at home after discharge(p<0.05). There was no difference between the groups in the incidence of nausea and vomiting but urinary retention at the recovery room was more frequent in group C than other groups(p<0.05). CONCLUSIONS: Caudal block provided more effective postoperative analgesia than local infiltration. In caudal block, the addition of ketamine or clonidine prolongs the duration of postoperative analgesia without significant increase in side effects.

Successful Pain Management for the Postherpetic Neuralgia of Ophthalmic Nerve by Continuous Subcutaneous Infusion of Ketamine: A case report / 대한마취과학회지

A 25-year-old woman transferred to pain clinic complaining of severe throbbing eye ball pain, eyelid edema and severe tearing in her left eye under the diagnosis of herpes zoster ophthalmicus that was developed 3months ago. In addtion to conventional medication, she had been taken stellate ganglion block, supraorbital and supratrochlear nerve block to contol of pain, but the response was poor. So we tried to administer ketamine subcutaneously, because not only ketamine, NMDA receptor antagonist, played a significant role to reduce neuropathic pain and pain caused by nerve injury, but also she wanted to work in her office during the treatment. We used subcutaneous ketamine 3 mg/hr (0.06 mg/kg/hr) in patient with postherpetic neuralgia of the ophthalmic nerve, and accomplished almost complete pain relief without any sign of side effect.