Enhanced Recovery After Surgery linked to lower CRS-HIPEC costs: micro-costing analysis in a European public hospital.

[BACKGROUND] Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is technically complex and resource-intensive. The primary objective of this study was to perform a detailed micro-costing analysis of CRS-HIPEC. As a secondary, exploratory objective, we evaluated whether adherence to an Enhanced Recovery After Surgery (ERAS) pathway was associated with differences in postoperative resource utilisation and direct hospital costs.

[MATERIALS AND METHODS] A retrospective observational analysis was conducted on all consecutive CRS-HIPEC procedures performed from 2021 to 2023 in a Spanish tertiary public centre. Resource use and cost determinants were assessed using micro-costing methods. An exploratory comparison between ERAS and non-ERAS management periods was performed.

[RESULTS] The median cost of CRS-HIPEC was €26,386. Higher expenditure was associated with longer hospital stays, higher PCI scores, need for anastomosis and infectious complications. ERAS and non-ERAS cohorts showed similar case complexity. Despite partial implementation, ERAS adherence was associated with shorter median hospital stay (8 vs 13 days, p < 0.001) and lower total median costs (€20,452.5 vs €27,346.7, p = 0.02), without an increase in severe postoperative complications (Clavien-Dindo ≥ III: 17.2 % vs 25.0 %, p = 0.454). The multivariable model (including PCI, anastomosis and severe complications) showed good discriminative performance for identifying high-cost cases (AUC = 0.923; 95 % CI 0.851-0.976).

[CONCLUSIONS] CRS-HIPEC costs are predominantly driven by hospital stay and complication-related resource utilisation. The exploratory ERAS analysis suggests that even partial adherence may reduce postoperative stay and costs without increasing morbidity. These findings highlight the importance of perioperative optimisation to improve the clinical and economic efficiency of CRS-HIPEC programmes.