[Study on the clinical effect of initiating continuous blood purification at different times for severe acute pancreatitis].

Objective: To observe the clinical effect of initiating continuous blood purification (CBP) treatment at different times for patients with severe acute pancreatitis (SAP), and to explore the optimal timing for starting CBP treatment for SAP, so as to provide evidence for clinicians to start CBP treatment.

Methods: A retrospective cohort study was used to select patients with SAP who received CBP treatment in People's Hospital of Hunan Province from January 2020 to December 2023. According to the timing of CBP initiation, the patients were divided into early initiation group (diagnosis of SAP to the first CBP treatment time < 24 hours) and late initiation group (diagnosis of SAP to the first CBP treatment time of 24-48 hours). The general data, acute physiology and chronic health evaluation II (APACHE II), bedside index for severity in acute pancreatitis (BISAP) score and laboratory indicators, local complications and systemic complications, intensive care unit (ICU) treatment time, hospital stay, treatment cost, and clinical outcome of the two groups were collected and compared.

Results: A total of 130 patients with SAP who received CBP treatment were enrolled, including 90 patients in the early initiation group and 40 patients in the late initiation group. Before treatment, there were no significant differences in gender, age, APACHE II score, BISAP score, etiology and laboratory examination indexes between the early initiation group and late initiation group. At 48, 72, 96 hours after treatment, the blood calcium level of the two groups was significantly higher than that before treatment, and the levels of white blood cell count (WBC), C-reactive protein (CRP), lactic acid, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), APACHE II score and BISAP score were significantly lower than those before treatment. The WBC level, APACHE II score and BISAP score of the late initiation group were significantly lower than those of the early initiation group at 72 hours and 96 hours after treatment [WBC (×10⁹/L): 10.96 (8.68, 13.04) vs. 12.45 (8.93, 16.30) at 72 hours after treatment, and 10.18 (8.68, 12.42) vs. 11.96 (8.81, 16.87) at 96 hours after treatment; APACHE II score: 9.50 (5.75, 12.00) vs. 11.00 (6.25, 14.00) at 72 hours after treatment, and 10.00 (4.00, 12.00) vs. 12.00 (7.00, 14.75) at 96 hours after treatment; BISAP score: 2.35±1.03 vs. 2.76±1.10 at 72 hours after treatment, and 2.08±1.21 vs. 2.70±1.11 at 96 hours after treatment], the differences were statistically significant (all P < 0.05). In terms of complications, the incidence of pancreatic abscess in the late initiation group was significantly lower than that in the early initiation group [5.00% (2/40) vs. 20.00% (18/90)], but the incidence of abdominal compartment syndrome was significantly higher than that in the early initiation group [42.50% (17/40) vs. 13.33% (12/90)], the differences were statistically significant (all P < 0.05). In addition, the ICU treatment time in the early initiation group was significantly shorter than that in the late initiation group [days: 11.00 (6.00, 20.00) vs. 15.00 (9.75, 25.00), P < 0.05], and there were no statistically significant differences in hospitalization costs, length of stay and mortality between the two groups.

Conclusions: CBP can effectively increase the level of blood calcium and decrease the level of lactic acid and inflammatory factors. Starting CBP within 24-48 hours after diagnosis of SAP can reduce WBC level and disease severity score faster, and reduce the occurrence of pancreatic abscess. Initiation of CBP within 24 hours after diagnosis of SAP can reduce the incidence of abdominal compartment syndrome and shorten the duration of ICU treatment.