Risk scoring system for thoracic surgery patients have not been widely used, as of recently. We tried to forge a risk scoring system that predicts the risk of postoperative complications in patients undergoing major thoracic surgery. We used a prolonged ICU stay as a representative of postoperative complications and tested various possible risk factors for its relation.

Data from all patients who underwent major lung and esophageal cancer surgeries, between 2005 and 2007 in our hospital, were collected retrospectively (n = 858). Multiple logistic regression analysis was performed with various possible risk factors to build the risk scoring system for prolonged ICU stay (> 3 days).

A total of 9% of patients exhibited more than 3 days of ICU stay. Age, operation name, preoperative lung injury, no epidural analgesia, and predicted post operative forced expiratory volume in 1 second (ppoFEV1) were the risk factors for prolonged ICU stay, by multivariable analysis (P < 0.05). Risk score, p was derived from the formula: logit(p/[1-p]) = -5.39 + 0.06 × age + 1.12 × operation name(2) + 1.52 × operation name(3) + 1.32 × operation name(4) + 1.56 × operation name(5) + 1.30 × preoperative lung injury + 0.72 × no epidural analgesia - 0.02 × ppoFEV1 [Age in years, operation name(2): pneumonectomy, operation name(3): esophageal cancer operation, operation name(4): completion pneumonectomy, operation name(5): extended operation, preoperative lung injury(+), epidural analgesia(-), ppoFEV1 in %].

Age, operation name, preoperative lung injury, epidural analgesia, and ppoFEV1 can predict postoperative morbidity in thoracic surgery patients.