A prediction model based on nutritional variables of postoperative pulmonary infection after colorectal cancer surgery.

BACKGROUND

Postoperative pulmonary infection (PPI) remains a significant complication in elderly patients with colorectal cancer (CRC). This study aimed to identify risk factors for PPI and develop a predictive model for PPI.

METHODS

A retrospective analysis was conducted on 339 elderly patients with CRC undergoing radical resection. Patients were categorized into PPI and non-PPI groups. Clinical, surgical, and laboratory variables were collected. Univariate and multivariate logistic regression analyses were performed, and independent predictors of PPI were identified. A nomogram was constructed and validated internally by R.

RESULTS

In a study of 339 patients, 40 individuals developed PPI with an incidence of 11.8%. The study identified five independent risk factors: advanced age (OR = 1.13, 95%CI: 1.03-1.25, P = 0.014), increased mFI positive items (OR = 3.19, 95%CI: 1.70-5.99, P < 0.001), elevated CONUT (OR = 2.23, 95%CI: 1.25-3.98, P = 0.007), decreased GNRI (OR = 0.94, 95%CI: 0.90-0.99, P = 0.010) and PNI scores (OR = 0.88, 95%CI: 0.81-0.97, P = 0.010). The nomogram displayed good discrimination (AUC: 0.82) and calibration. Independent validation from the same institution confirmed excellent performance (AUC: 0.866).

CONCLUSIONS

Age, mFI, and poor nutritional status are independent predictors of PPI in elderly patients with CRC. This nomogram serves as a practical tool for individualized risk assessment and perioperative management.