Effect of implementing the European guidelines for functional evaluation before lung resection on cardiorespiratory morbidity and 30-day mortality in lung cancer patients: a case-control study on a matched series of patients

OBJECTIVES: We hypothesized that postoperative cardiorespiratory morbidity and/or 30-day death rates decreased after implementing the new European ERS/ESTS guidelines for functional evaluation before lung resection and tested the hypothesis by means of a case-control study. METHODS: The analysis included a series of 916 consecutive patients who underwent an anatomical pulmonary resection for non-small-cell lung cancer in our centre. Patients were divided into cases (September 2009-August 2012) and controls (December 2002-August 2009). We reviewed the records from a prospective computerized database; the final dataset included no missing data. The primary studied outcomes were the occurrence of cardiorespiratory morbidity or 30-day death after surgery. The patients were 1:1 propensity score matched according to the following variables age, ppoFEV1% and the need of pneumonectomy. RESULTS: After the matching process, 670 cases (335 cases and 335 controls) entered into the study. The rates of pneumonectomy in cases and controls were 5.7 and 13.2%, respectively, (P < 0.0001) in the whole series and 5.7 and 6.9% after matching (P = 0.52). Cardiorespiratory morbidity was 8.1% (27 of 308) in cases and 9.8% (33 of 335) in controls [odds ratio (OR): 0.8; 95% confidence interval (CI): 0.4-1.4]. Thirty-day mortality was 0.90% (3/335) in cases and 1, 2% (4 of 335) in controls (OR: 0.7; 95% CI: 0.1-4.4). CONCLUSIONS: Although we have observed a trend towards lower cardiorespiratory morbidity and 30-day mortality after implementing ERS/ESTS guidelines, the benefit of the guidelines remains unclear. Multicentric analysis including a very large number of cases is needed to demonstrate statistically the effectiveness of the guidelines to reduce operative mortality and cardiorespiratory morbidity. Maybe the effect could be easier demonstrated in series with higher operative mortality or morbidity.