The purpose of this study is to use Neuman system model to analyze the impact of postoperative fatigue (POF) in bladder cancer patients and its potential mechanism.

A prospective cohort design was used to include 200 patients who underwent bladder cancer surgery in a Grade III Grade A hospital from June 2023 to June 2024. According to the three defense lines of the Neumann system model (basic structure defense line, resistance line, and recovery/adaptation line), the Fried frailty scale was used to assess frailty status, the Brief Mental Health Scale (GHQ-12) was used to assess the patient's psychological state, and the Social Support Scale (SSS) was used to assess the patient's level of social support.

This study showed that the incidence of postoperative weakness was 55%, with the highest incidence of fatigue (70%) and the lowest incidence of decreased grip strength (30%). Logistic regression analysis showed that age (OR=1.05, P=0.003), postoperative complications (OR=2.34, P=0.023), low level of social support (OR=1.76, P=0.021), and poor mental health (OR=3.12, P=0.001) were significantly positively related to postoperative weakness of bladder cancer.

The application of Neuman system model reveals that postoperative weakness of bladder cancer patients is the result of interaction, which provides a theoretical basis for clinical medical staff to identify and manage the risk factors of postoperative weakness of bladder cancer patients.