Predisposing factors and clinical impact of high-output syndrome after sphincter-preserving surgery with covering ileostomy for rectal cancer: a retrospective single-center cohort study

Background Ileostomy-related high-output syndrome has become a major cause of postoperative morbidity after rectal cancer surgery. This study aimed to clarify the predisposing factors and clinical impact of high-output syndrome. Methods Clinical parameters that were associated with high-output syndrome and clinical impact of high-output syndrome on nutritional status, electrolyte abnormality and renal dysfunction were retrospectively investigated in consecutive patients with rectal cancer undergoing resection with covering ileostomy during 2016–2017. Results High-output syndrome developed in 44/195 eligible patients (22.6%). Multivariable analysis revealed that neoadjuvant (chemo)radiotherapy [odds ratio (OR): 2.4; 95% confidence interval (CI) 1.1–5.2; P = 0.02], postoperative complications (OR: 2.2; 95% CI 1.0–4.6; P = 0.049), postoperative maximal white blood cell ≥ 10,000 cells/μl (OR: 4.0; 95% CI 1.9–8.8; P = 0.0004), and postoperative maximal C-reactive protein ≥ 10 mg/dl (OR: 2.4; 95% CI 1.1–5.2; P = 0.02) were independently associated with high-output syndrome. High-output syndrome was associated with increased renal dysfunction at the time of ostomy closure (29.6% versus 11.9%, patients with high-output syndrome vs. without high-output syndrome, P = 0.008), but not with nutritional imbalance or electrolyte abnormalities. High-output syndrome (OR: 2.5; 95% CI 1.1–5.9; P = 0.03) and postoperative maximal C-reactive protein ≥ 10 mg/dl (OR: 2.4; 95% CI 1.0–5.6; P = 0.04) were independently associated with renal dysfunction at ostomy closure. Conclusion Preoperative (chemo)radiotherapy, postoperative inflammatory response, and postoperative complications predisposed to high-output syndrome, and it significantly impacted postoperative renal dysfunction. Active monitoring and early intervention are warranted to prevent renal dysfunction in patients with these factors.