A real-world study on the influence of unplanned reoperations on hospitalized patients using the diagnosis-related group

Abstract

Objective: The issue of unplanned reoperations poses significant challenges within healthcare systems, with assessing their impact being particularly difficult. The current study aimed to assess the influence of unplanned reoperations on hospitalized patients by employing the diagnosis-related group (DRG) to comprehensively consider the intensity and complexity of different medical services.

Methods: A retrospective cohort study of surgical patients was conducted at a large tertiary hospital with two hospital districts employing data sourced from a DRG database. Hospital length of stay (LOS) and hospitalization costs were measured as the primary outcomes. Discharge to home was measured as the secondary outcome. Frequency matching based on DRG, regression modeling, subgroup comparison and sensitivity analysis were applied to evaluate the influence of unplanned reoperations.

Results: We identified 20820 surgical patients distributed across 79 DRGs, including 188 individuals who underwent unplanned reoperations and 20632 normal surgical patients in the same DRGs. After DRG-based frequency matching, 564 patients (188 with unplanned reoperations, 376 normal surgical patients) were included. Unplanned reoperations led to prolonged LOS (before matching: adjusted difference, 12.05 days, 95% confidence interval [CI] 10.36-13.90 days; after matching: adjusted difference, 14.22 days, 95% CI 11.36-17.39 days), and excess hospitalization costs (before matching: adjusted difference, $4354.29, 95% CI: $3,817.70-$4928.67; after matching: adjusted difference, $5810.07, 95% CI $4481.10-$7333.09). Furthermore, patients who underwent unplanned reoperations had a reduced likelihood of being discharged to home (before matching: hazard ratio [HR] 0.27, 95% CI 0.23-0.32; after matching: HR 0.31, 95% CI 0.25-0.39). Subgroup analyses indicated that the outcomes across the various subgroups were mostly uniform. In high-level surgery subgroups (levels 3-4) and in relation to complex diseases (relative weight ≥ 2), the increase in hospitalization costs and LOS was more pronounce after unplanned reoperations. Similar results were observed with sensitivity analysis by propensity score matching and excluding short LOS.

Conclusions: Incorporating the DRG allows for a more effective assessment of the influence of unplanned reoperations. In managing such reoperations, mitigating their influence, especially in the context of high-level surgeries and complex diseases, remains a significant challenge that requires special consideration.

Keywords: Unplanned reoperation; diagnosis-related group; discharge to home; hospital length of stay; hospitalization cost; retrospective cohort study.

Figure 1.

Flow chart of study participants.

Figure 2.

Probability of discharge to home of study participants. (A) Probability of discharge to home of study participants before matching. (B) Probability of discharge to home of study participants after DRG-based frequency matching.

Figure 3.

Forest plots of subgroup analyses for LOS. (A) Forest plot of subgroup analyses for LOS before matching. (B) Forest plot of subgroup analyses for LOS after DRG-based frequency matching. Subgroup analyses with adjusted differences and 95% confidence intervals for LOS adjusted, if not be stratified, for hospital district, age, sex, adverse event, surgery category, surgery level, and RW.

Figure 4.

Forest plots of subgroup analyses for hospitalization costs. (A) Forest plot of subgroup analyses for hospitalization costs before matching. (B) Forest plot of subgroup analyses for hospitalization costs after DRG-based frequency matching. Subgroup analyses with adjusted differences and 95% confidence intervals for hospitalization costs adjusted, if not be stratified, for hospital district, age, sex, adverse event, surgery category, surgery level, and RW.).