This prospective study intends to investigate the incidence of postoperative pulmonary complications (PPC) or in-hospital mortality in patients with COPD or at risk for COPD undergoing high-risk noncardiac major surgery and to identify relevant risk factors. This study aims to quantify and compare the diagnostic performance of preoperative functional tests, exercise capacity, clinical assessment tests and predictive scoring systems to predict PPC or in-hospital mortality in these patients.

COPD is associated with high perioperative morbidity and mortality and PPC frequently occur in these patients. However, concepts for preoperative pulmonary risk assessment and the predictive value of routine preoperative exercise capacity, clinical assessment and pulmonary function tests are still poorly characterized.

Objectives:

• To determine the incidence of the composite end point of PPC or all cause in-hospital mortality in patients with confirmed COPD (spirometry) and patients with clinical risk factors in whom spirometry disproved COPD.
• To determine the predictive value of exercise capacity, clinical assessment tests, pulmonary function tests and predictive scoring systems to predict the composite end point in these patients.
• To identify relevant risk factors and predictors associated with the composite end point.

Methodology:

Prospective single-centre observational study

All patients receive a structured preoperative pulmonary risk assessment with:

1. standardized clinical questionnaire
2. COPD Assessment Test (CAT™)
3. exercise capacity (symptom-limited stair climbing)
4. spirometry
5. capillary blood gas Analysis

Postoperative follow-up is planned between the 2nd and 5th day after extubation.

Inclusion Criteria:

• 18 years and older
• High-risk noncardiac major surgery with an anticipated operation time ≥ 120 minutes and/or planned postoperative intensive care unit admission
• Typical clinical signs for COPD (dyspnea, chronic cough, chronic sputum production, exposure to risk factors)
• Confirmed COPD (medical history) or clinical risk factors for COPD
• Positive COPD Assessment Test (CAT™)

Exclusion Criteria:

• < 18 Years
• Pregnancy
• Lack of cooperation
• Inability to provide functional tests like spirometry or stairclimbing

Patients scheduled for major surgery, who present in the pre-assessment clinic of the University Medical Center Hamburg-Eppendorf during the study recruitment period, will be screened for eligibility. Patients with typical clinical signs and a positive COPD Assessment Test (CAT™) qualify for spirometry. After informed consent 80 patients with disproved COPD (FEV1/FVC ratio ≥ 0.70) and 240 patients with confirmed COPD (FEV1/FVC ratio < 0.70) will consecutively be analysed.