• The Korean Journal of Pain
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• v.21 no.2
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• pp.106-111
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• 2008

Background: Chronic pain after thoracotomy has been recently reproduced in a rat model that allows investigating the effect of potentially beneficial drugs that might reduce the incidence of allodynia or alleviate pain. Local anesthetics produce antinociception in normal animals and alleviate mechanical allodynia in animals with nerve injury although their mechanisms of action may differ in these situations. Our purpose of this study was to test whether the preoperative intercostal nerve block of bupivacaine could prevent the development of allodynia in a rat model of chronic postthoracotomy pain. Methods: All male Sprague-Dawley rats were anesthetized and the right 4th and 5th ribs were exposed surgically. The pleura were opened between the ribs to which a retractor was placed and was opened 10 mm in width. Retraction was maintained for one hour. Total 1 mg of 0.5% bupivacaine was injected at the intercostal nerves before (n = 17) or after (n = 16) surgery. A control group (n = 25) that underwent rib retraction did not receive any drug. Rats were tested for mechanical allodynia using calibrated von Frey filaments applied around the incision site during the three weeks following surgery. Results: The incidence of development of mechanical allodynia in the group that received intercostal injection with bupivacaine before surgery was significantly lower than that in the control group (P < 0.05). Conclusions: Preoperative intercostal nerves block around the surgical incision before thoracotomy may decrease the incidence of postthoracotomy pain syndrome.

• The Korean Journal of Pain
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• v.14 no.1
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• pp.68-75
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• 2001

Background: Thoracotomy is the operation that produces the most postoperative pain, necessitating the highest requirements for postoperative analgesics. The common methods of treating postthoracotomy pain are the use of thoracic epidural analgesia, intemittent or continuous intercostal nerve blocks, intravenous narcotics and cryoanalgesia. We designed to assess the analgesic effect of epidural analgesia, cryoanalgesia and the combined analgesia in thoracic surgery. Methods: A prospective study was carried out in 59 patients undergoing elective thoracotomy for parenchymal disease. Patients were randomized into three groups: C (cryoanalgesia), CE (cryoanalgesia and thoracic epidural analgesia), E (epidural analgesia). All patients had standard anesthesia with endotracheal intubation using a double lumen endotracheal tube, and one-lung ventilation. Subjective pain relief was assessed on a visual analog scale. Analgesic requirements, complications and the degree of satisfaction were evaluated during the 7 days following surgery. Results: Subjective pain relief was significantly better in Group CE and Group E in comparison with Group C (P < 0.05). Cryoanalgesia provided a better pain score on the 6th and 7th POD than the early postoperative periods. Analgesic requirements were higher in Group C than in the Group CE and Group E during the first POD. The incidence of side effects was similar in Group CE and Group E. Conclusions: If we can reduce the concentration of fentanyl and local anesthetics in combined analgesia of epidural and cryoanalgesia, the disadvantages of each method would be overcome and would be a better method of postthoracotomy pain control.

• Journal of Chest Surgery
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• v.26 no.7
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• pp.538-542
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• 1993

An approach to the treatment of post-operative pain by the injection of bupivacaine into the pleural space through an intrapleural cathter has been studied. Among 24 thoracotomy patients, bupivacaine was injected only to experimental group[ 12 patients ] when the patient was able to head up for oneself during recovery from anesthesia. The pain and ROM[ range of motion ] scores, respiration rate, PaCO2 level of both experimental and control group were measured at the time of head-up and 30 and 120 minutes thereafter.The scores of pain and ROM of experimental group were significantly[ P value < 0.05 ] decreased in 30 minutes and 120 minutes after bupivacaine injection compared with those of control group but respiration rate and PaCO2 level were not changed significantly. With this result, we can suggest that intrapleural injection of bupivacaine is useful for pain relief following thoracotomy.