Abstract: Objective  To explore the relationship between the start time of plasma diafiltration (PDF) intervention with artificial liver and the in-hospital prognosis of the patients with hepatitis B-related acute chronic liver failure (HBV-ACLF).  Methods  The patients diagnosed with HBV-ACLF from January 1 2017 to December 31, 2021 were selected and divided into an improved group and a non-improved group according to their in-hospital prognosis. Univariate and multivariate logistic regression analyses were performed using their demographics, baseline laboratory examinations, and in-hospital prognosis of the two groups to obtain the independent influencing factors. Smooth curve fitting was used to explore the correlation between start time of PDF and in-hospital prognosis.  Results  A total of 88 patients were included, with 60 patients in the improved group (68.2%). Univariate logistic regression showed that start time of PDF intervention (OR=1.03,95% CI: 1.01~1.04,P＜0.001), age (OR=1.06, 95% CI:1.02~1.11,P=0.005), baseline blood alanine aminotransferase (OR=1.00, 95% CI:1.00~1.00, P=0.012), and baseline abdominal infection (OR=3.13, 95% CI: 1.20~8.14, P=0.019) were the possible influencing factors for in-hospital prognosis. Multivariate logistic regression showed that the start time of PDF intervention (OR=1.04,95% CI: 1.02~1.05,P＜0.001), age (OR=1.08,95% CI:1.01~1.14, P=0.038), and HBV-ACLF at an early stage (OR=0.13, 95% CI:0.02~0.98,P=0.048) were the independent influencing factors for adverse in-hospital prognosis. There may be a threshold effect between the start time of PDF intervention and adverse in-hospital prognosis. The segmented regression model showed that the optimal threshold was 72 hours, less than 72 hours with the OR=0.75 (95% CI: 0.53~1.05,P=0.089), and more than 72 hours with the OR=1.04(95% CI:1.02~1.06,P＜0.001).  Conclusion  There was a threshold effect between the start time of PDF intervention and the adverse in-hospital prognosis of the patients. Preoperative evaluation and initiation of PDF intervention within 72 hours after the diagnosis of HBV-ACLF may be one of the potential opportunities of clinical treatment.

Key words: Hepatitis B, Acute-on-chronic liver failure, Artificial liver, Plasma diafiltration, Intervention time