Retrospective analysis of hypotension incidence and related factors during double filtration plasmapheresis ( DFPP ) in critically ill patients

OBJECTIVE: This study aimed to investigate the incidence and risk factors associated with hypotension in critically ill patients undergoing double filtration plasmapheresis (DFPP) to improve treatment safety and optimise haemodynamic management strategies. METHODS: A retrospective analysis was conducted on critically ill patients who underwent DFPP in the intensive care unit between April 2022 and April 2024. Patients were classified into hypotension and non-hypotension groups based on blood pressure changes following DFPP. Clinical data including APACHE II and SOFA scores, DFPP treatment parameters, blood access methods, anticoagulation strategies and vasopressor usage were compared between the groups. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors. Time to hypotension onset during DFPP was also analysed. RESULTS: A total of 61 patients undergoing 190 DFPP sessions were included, with hypotension occurring in 86.8% of patients during one or more sessions. The APACHE II score was significantly higher in the hypotension group (p = 0.002). Logistic regression analysis identified systemic heparin anticoagulation (OR = 2.475, p = 0.013) and pre-existing vasopressor use (OR = 23.229, p = 0.002) as independent risk factors for hypotension. Additionally, single-needle blood access was associated with a higher incidence of hypotension (p = 0.023). Notably, 76.9% of hypotensive episodes occurred within the first 2 h of DFPP, with 41.7% occurring within the first hour. CONCLUSION: Systemic heparin anticoagulation and prior vasopressor use were significantly associated with an increased risk of hypotension during DFPP. These associations may reflect both treatment-related physiological effects and the intrinsic haemodynamic fragility of severely ill patients. Optimising vascular access, anticoagulation strategies and vasopressor management may help improve haemodynamic stability during DFPP, particularly in high-risk individuals. However, prospective studies are still needed to determine whether such adjustments can meaningfully reduce the incidence of DFPP-related hypotension.