Effects of TrkA inhibitory peptide on cancer-induced pain in a mouse melanoma model.

PURPOSE: Tropomyosin receptor kinase (Trk) A, a high-affinity receptor of nerve growth factor, is a therapeutic target for both noxious and neuropathic pain. The present study examined the effects of an inhibitory peptide of Trk activity (IPTRK) 3 that inhibits TrkA activity on cancer-induced pain in a mouse melanoma model. METHODS: The hind paws of mice were inoculated with B16-F1 mouse melanoma cells on day 0. We administered IPTRK3 (20 mg/kg i.p.) repetitively on days 5, 6, 7, 8, and 9, and evaluated pain-related behaviors on days 0, 5, 10, 15, and 20 after tumor inoculation. RESULTS: Following inoculation, mice demonstrated mechanical allodynia and thermal hyperalgesia with an increased number of flinches, and paw volume increased gradually. However, an intraperitoneal injection of IPTRK3 significantly inhibited mechanical allodynia on day 15 and suppressed the number of flinches on day 20. The increased paw volume was significantly suppressed on day 20 after tumor inoculation. IPTRK3, however, showed no significant effect on thermal hyperalgesia. CONCLUSIONS: These results suggest that TrkA inhibitory peptide likely suppress melanoma-induced pain with concomitant reduction in the increased paw volume in a mouse skin cancer pain model.

[The use of rocuronium in a patient with Becker muscular dystrophy].

We report a case of thoracoscopic pulmonary resection for pneumothorax in a patient with Becker muscular dystrophy The sensitivity of nondepolarizing muscle relaxant in a patient with muscle dystrophy is reportedly higher than in a patient without muscle disease, and the duration of the effect is known to be prolonged. In a 26-year-old man (height 160 cm, weight 39 kg) with Becker muscular dystrophy, general anesthesia was induced with target controlled infusion of propofol (3.0 microg x ml(-1)) and 0.4 microg x kg(-1) of min(-1) of remifentanil. A small amount of rocuronium was also administered additionally until TOF ratio reached to 0%. Total amount of rocuronium was 20 mg (0.5 mg x kg(-1)) for intubation with a double-lumen tracheal tube. The duration of surgery was 68 min. We confirmed 84% recovery of TOF ratio 90 min after injection of rocuronium, and extubated the patient without reversal of rocuronium. We found that the maximum concentration in the plasma or effective site (Cp/Ce) of rocuronium was reached at the time of intubation.

[Educational efficacy of computer software showing the effect-site concentration of fentanyl in anesthesia training].

BACKGROUND: We investigated the efficacy of computer software showing the effect-site concentration of fentanyl in anesthesia training. METHODS: All patients were randomly divided into the following three groups. Anesthesia management was performed with a pharmacokinetic simulation program by anesthesia residents with experience in using it for less than 3 months (P (+) group, n = 32). Anesthesia management was performed without a pharmacokinetic simulation program by anesthesia residents with experience in using it for less than two weeks (P (-) group, n = 25). Anesthesia management was performed without a pharmacokinetic simulation program by anesthesia residents with no experience in using it, under supervision of experienced anesthesiologists (C group, n = 22). We measured the effect-site concentration of fentanyl (Ce of fentanyl) at the end of surgery, intraoperative total doses of fentanyl and propofol, the time required from the end of operation to extubation, and frequency of analgesics required within 24 hours. RESULTS: Total doses of fentanyl were significantly more in P (+) group than in other two groups. Ce of fentanyl were significantly more in P (+) group than in other two groups. CONCLUSIONS: A pharmacokinetic simulation program is useful for anesthesia residents.

[Perioperative anesthetic management of a patient with multiple sclerosis].

We report general anesthesia for a patient with multiple sclerosis (MS). A 40-year-old male patient with a 13-year history of MS was scheduled for laparoscopic surgery. The symptoms of MS had been exacerbated during feverish state or under surgical stress in the previous surgeries. To prevent surgical stress response and postoperative fever, we performed epidural anesthesia with continuous intravenous infusion of propofol and fentanyl during surgery. Flurbiprofen axetil was used for slight postoperative fever. There was no clinical exacerbation of MS during perioperative period. In conclusion, appropriate control of surgical stress and prevention of fever are important for perioperative anesthetic management of patients suffering from MS.

[Continuous intravenous administration of fentanyl reduces tenesmus after transurethral resection of the prostate (TUR-P)].

BACKGROUND: The relief from tenesmus is important after transurethral resection of the prostate (TUR-P). We evaluated the effect of continuous intravenous administration of fentanyl on the tenesmus. METHODS: Eleven patients receiving fentanyl infusion (fentanyl group) were compared with fourteen patients without fentanyl infusion (control group) retrospectively. All patients underwent TUR-P under spinal anesthesia with hyperbaric 0.5% bupivacaine 2.2-2.8 ml. In the fentanyl group, fentanyl infusion 25 microg x hr(-1) was started followed by fentanyl 50 microg administration postoperatively. RESULTS: In the fentanyl group, NSAIDs were needed in only one patient. Eleven patients in the control group, however, required NSAIDs and three of them needed additional pentazocine administration. The required amount of NSAIDs per patient was significantly smaller in the fentanyl group (Mann-Whitney U test, P < 0.01). In the fentanyl group, one patient had slight nausea but needed no care. Other side effects, such as respiratory depression, hypotension, bradycardia and somnolence were not observed. CONCLUSIONS: Continuous intravenous administration of fentanyl was very effective and safe enough for the tenesmus after TUR-EP.

[Two cases of atraumatic iliopsoas hematoma].

We report two cases of atraumatic iliopsoas hematoma. First patient was a 76-year-old man admitted to our hospital from appetite loss. Blood transfusion did not improve his anemia. Five days after admission, suddenly he went into shock. CT scan revealed ileopsoas hematoma. He died from hemorrhagic shock in spite of conservative therapy. Second patient was a 70-year-old man admitted because of acute heart failure. Continuous hemodiafiltration was required to relieve anuria. The next day, he developed left leg and hip pain. CT scan revealed ileopsoas hematoma and he received CT guided aspiration drainage for decompression, but almost 7 days were needed to achieve successful pain control. In a case of iliopsoas hematoma, early diagnosis and adequate choise of therapy are necessary to improve prognosis of patients.