Procalcitonin levels after different types of conventional thoracic surgery

Background: Procalcitonin (PCT) is currently discussed as an indicator of postoperative complications following thoracic surgery. Serum levels of PCT are different after thoracoscopic and conventional surgical approaches. We conducted this study to test the hypothesis that different types of conventional thoracic surgery are associated with different postoperative serum levels of acute-phase proteins or pro-inflammatory mediators. Methods: Serum levels of interleukin (IL)-6, C-reactive protein (CRP), lipoprotein-binding protein (LBP) and PCT were measured preoperatively (pre), immediately after surgery (0 h), 6 hours after surgery (6 h), and on the 1st (d1), 3rd (d3) and 5th (d5) postoperative days in 48 patients undergoing elective conventional pneumonectomy (n = 6), lobectomy (n = 20) or wedge resection (n = 22). Results: In all study groups, IL-6 and PCT increased after surgery, peaking at 6 h and on d1, respectively. The time courses of IL-6, CRP, LBP and PCT release were not influenced by the type of surgical procedure. All parameters increased more markedly after lobectomy and wedge resection than after pneumonectomy. Conclusions: Surgical trauma and lung ischaemia/reperfusion injury could be the main factors determining the release of IL-6 and PCT after surgery. From an immunological point of view, pneumonectomy is less severe than wedge resection or lobectomy in terms of tissue injury. Different types of conventional thoracic surgery are associated with differences in postoperative PCT and IL-6 synthesis. For this reason, expected ranges of PCT and IL-6 levels should be established for the various surgical procedures before these parameters can be used as indicators of postoperative complications.