Comparative Study of Continuous Intercostal Nerve Block and Epidural Anesthesia for Postoperative Analgesia in Thoracotomy
The main reasons for the less effective analgesia with continuous intercostal nerve block (CINB) are: 1) the anterior branch of the intercostal nerve and the communicating branches to the contralateral chest wall, meaning that the selection of an anterolateral incision cannot completely block pain transmission; 2) incomplete local accumulation of medication on the parietal pleura. Considering preoperative pleural adhesions, surgery may compromise the integrity of the parietal pleura or require the selection of an anterolateral incision, so patients should use continuous epidural anesthesia (CEA) for analgesia.
In the South China National Defense Medical Journal in 2005, it was found that the side effects of CINB analgesia were significantly less than those of CEA. Due to serious complications from CEA, mainly respiratory inhibition, thoracic CEA affects the movement of the diaphragm by blocking the intercostal muscles and intraoperative muscle relaxants, hindering the recovery of pulmonary function. In this study, group A showed higher PCO2 indicators than group B at 4-24 hours postoperatively, indicating to some extent the suppression of early postoperative ventilatory function by CEA. Differences due to individual variations in sex and drug dosage have been reported, with incidences of respiratory inhibition from CEA varying considerably, ranging from 0.9% [6J to 13.5% [’J]. Additionally, CEA is prone to forming bilateral sympathetic blocks, leading to bradycardia or hypotension and other hemodynamic changes, especially in elderly patients. Due to nerve dysfunction and decreased sympathetic nerve activity, these patients are more likely to experience significant fluctuations in heart rate and blood pressure. Although the incidence of these complications has declined in recent years with improvements in CEA techniques and drugs, finding the balance between optimal drug dosage and analgesic effect for individual patients remains very challenging and unpredictable, with potential dangers often being life-threatening. Therefore, for elderly patients with poor cardiac and pulmonary function, using CEA analgesia requires careful monitoring during the early postoperative period.
Elderly patients receiving CINB analgesia can significantly reduce respiratory and circulatory complications, protect postoperative cardiopulmonary function, and reduce the burden of postoperative care. Compared to traditional methods of analgesia, both CEA and CINB offer excellent analgesic effects that meet the requirements for post-thoracotomy analgesia. Under the premise of equal analgesic efficacy, CINB provides greater safety.