Clinical Frailty Score is a good predictor of postoperative mortality in patients undergoing open abdomen surgery: a multicenter retrospective cohort study

BACKGROUND: Open Abdomen (OA) is gaining popularity in damage control surgery (DCS) but there is not an absolute prognostic score to identify patients that may benefit from it. Our study investigates the correlation between the clinical frailty scale score (CFSS) and postoperative morbidity and mortality in patients undergoing OA. METHODS: Patients ≥65 yo undergoing OA in two referral centres between 2015 and 2020 were included and stratified according to CFSS in non-frail (NF), frail (F) and highly-frail (HF). The primary endpoint was 30-day mortality. Secondary endpoints were postoperative morbidity and 1- year survival. RESULTS: One hundred and thirty-six patients were included: 35 NF (25.7%), 56 F (41.2%), 45 HF (33.1%). Average age 76.8. The 73.5% of cases were non-traumatic diseases with no difference in preoperative characteristics. 95 (71.4%) had one complication, 26 NF (74.3%), 34 F (63.2%), 35 HF (77.8%) (P=0.301) and 59.4% had a complication with a CD≥3, 57.1% NF, 56.6% F and 64.4 HF. The 30-day mortality was 32.4%, higher in HF (46.7%) and F (30.4%) compared to NF (17.1%, P=0.018). The Overall 1-year survival was 41% (SE ±4) with statistically significant difference between HF vs. NF and HF vs. F (P=0.009 and P=0.029, respectively). In the univariate analysis, the only significant prognostic factor impacting mortality was CFSS, with HF having an HR of 1.948 (95% CI 1.097-3.460, P=0.023). CONCLUSIONS: When OA is a surgical option, frail patients should not be precluded, while HF should be carefully evaluated. The CFSS might be a good prognostic score for patients that may safely benefit from OA.