Table 1.
Baseline characteristics (n = 2,059).
Figure 1.
Recruitment flow chart.
Table 2.
Prevalence of postoperative pulmonary complications according to each type of surgery.
Table 3.
Results of logistic regression model to predict postoperative pulmonary complications (PPC) and assigned points based on regression coefficient to develop the PPC scoring index.
Figure 2.
The number of patients and the incidence of postoperative pulmonary complications (PPCs) by each point of the PPC scoring index (A) and by each risk class according to the PPC score (B).
PPC scores were calculated as follows: 1 point each for current smoker within 2 months, the presence of airflow limitation, American Society of Anesthesiologists ≥ class 2, and serum albumin <4.0 g/dL; 2 points each for age ≥70 years and emergency operation; and 4 points for cardiac/aortic aneurysm repair/abdominal open surgery without a laparoscopic procedure. PPC risk was classified according to the PPC score as follows: low, 0–3 points; intermediate 4–6 points; high, 7–9 points; very high, ≥10 points. Each bar graph shows the number of patients with each score for the PPC scoring index. Each broken line shows the incidence of PPCs for each point on the PPC scoring index. PPCs, postoperative pulmonary complications.