Small dose of naloxone as an adjuvant to bupivacaine in intrapleural infiltration after thoracotomy surgery: a prospective, controlled study

BACKGROUND: Severe pain always develops after thoracotomy; intrapleural regional analgesia is used as a simple, safe technique to control it. This study was performed to evaluate whether a small dose of naloxone with local anesthetics prolongs sensory blockade. METHODS: A prospective, randomized double-blinded controlled study was conducted on 60 patients of American Society of Anesthesiologists statuses I and II, aged 18 to 60 years, scheduled for unilateral thoracotomy surgery. After surgery, patients were randomly divided into two groups: through the intrapleural catheter, group B received 30 ml of 0.5% bupivacaine, while group N received 30 ml of 0.5% bupivacaine with 100 ng of naloxone. Postoperative pain was assessed using the visual analog pain scale (VAS). Time for the first request for rescue analgesia, total amount consumed, and incidence of postoperative complications were also recorded. RESULTS: The VAS score significantly decreased in group N, at 6 h and 8 h after operation (P < 0.001 for both). At 12 h after injection, the VAS score increased significantly in group N (P < 0.001). The time for the first request of rescue analgesia was significantly longer in group N compared to group B (P < 0.001). The total amount of morphine consumed was significantly lower in group N than in the bupivacaine group (P < 0.001). CONCLUSIONS: Addition of a small dose of naloxone to bupivacaine in intrapleural regional analgesia significantly prolonged pain relief after thoracotomy and delayed the first request for rescue analgesia, without significant adverse effects.

Intrapleural analgesia after endoscopic thoracic sympathectomy / Analgesia intrapleural após simpatectomia videotoracoscópica

PURPOSE: To compare analgesia traditionally used for thoracic sympathectomy to intrapleural ropivacaine injection in two different doses. METHODS: Twenty-four patients were divided into three similar groups, and all of them received intravenous dipyrone. Group A received intravenous tramadol and intrapleural injection of saline solution. Group B received intrapleural injection of 0.33 percent ropivacaine, and Group C 0.5 percent ropivacaine. The following aspects were analyzed: inspiratory capacity, respiratory rate and pain. Pain was evaluated in the immediate postoperative period by means of the visual analog scale and over a one-week period. RESULTS: In Groups A and B, reduced inspiratory capacity was observed in the postoperative period. In the first postoperative 12 hours, only 12.5 percent of the patients in Groups B and C showed intense pain as compared to 25 percent in Group A. In the subsequent week, only one patient in Group A showed mild pain while the remainder reported intense pain. In Group B, half of the patients showed intense pain, and in Group C, only one presented intense pain. CONCLUSION: Intrapleural analgesia with ropivacaine resulted in less pain in the late postoperative period with better analgesic outcomes in higher doses, providing a better ventilatory pattern.

OBJETIVO: Comparar a analgesia tradicionalmente utilizada para simpatectomia videotoracoscópica à injeção intrapleural de ropivacaína em duas doses diferentes. MÉTODOS: Vinte e quatro pacientes foram distribuídos em três grupos semelhantes, e todos eles receberam dipirona endovenosa. O grupo A recebeu tramadol endovenoso e injeção intrapleural de solução salina. O grupo B recebeu injeção intrapleural de ropivacaína a 0,33 por cento, e Grupo C ropivacaína a 0,5 por cento. Os aspectos analisados foram: capacidade inspiratória, freqüência respiratória e dor. A dor foi avaliada no período pós-operatório por meio da escala visual analógica e durante o período de uma semana. RESULTADOS: Nos grupos A e B, a redução da capacidade inspiratória foi observada no período pós-operatório. Nas primeiras 12 horas de pós-operatório, apenas 12,5 por cento dos pacientes nos grupos B e C apresentaram dor intensa em comparação a 25 por cento no Grupo A. Na semana seguinte, apenas um paciente do grupo A apresentou dor leve, enquanto o restante relatou dor intensa. No Grupo B, metade dos pacientes apresentou dor intensa, e no Grupo C, apenas um apresentou intensa dor. CONCLUSÃO: A analgesia intrapleural com ropivacaína resultou em menos dor no pós-operatório tardio com os melhores resultados analgésicos nas doses mais altas, proporcionando um melhor padrão ventilatório.