Objective: Thoracic epidural analgesia (TEA) reduces pulmonary complications after thoracotomy. Hypothetically, this advantage is partially because of the preserved pulmonary function, which is achieved by the reduction of postoperative pain and immobility. This study aimed to compare the principal methods of analgesia through early postoperative spirometric performance and gas exchange parameters after elective lung cancer surgery. TEA or intravenous analgesia (IVA) involving pethidine was used as the principal method in our sample population.
Material and methods: A total of 62 patients operated via the posterolateral thoracotomy approach were enrolled. Postoperative analgesia was secured using multimodal analgesia with either TEA with 0.1% bupivacaine or IVA. Pain perception was assessed with the visual analog scale (VAS) while at rest and on coughing. Arterial blood samples were collected at 1, 24, and 72 hours postoperatively. Preoperative and third postoperative day spirometric measurements were recorded.
Results: There were no significant differences among the groups in terms of demographic characteristics, properties of surgical technique, and disease-associated conditions. VAS scores of the TEA group were lower at the 72-hour follow-up, but a considerable fraction of these differences did not reach statistical significance. Reduction in the forced expiratory volume in the first second and forced vital capacities was more prominent in the IVA group on the third postoperative day, but these were not statistically significant either. Oxygenation parameters favored TEA but remained comparable. Finally, the pH values were significantly lower in the IVA group at 1 and 72 hours postoperatively (p=0.008 and p=0.02, respectively).
Conclusion: We believe that TEA is advantageous over IVA with alteration of respiratory volumes during the early postoperative period.