A pilot study into the use of Continuous Venous Hyperfiltration to manage patients in a critical state with dysregulated inflammation

Abstract

Introduction: Haemofiltration paradigms used to manage critically ill patients with a dysregulated inflammatory response (DIR) assess kidney function to monitor its onset, adaptation, and completion. A Continuous Venous Hyperfiltration (CONVEHY) protocol is presented, in which a non-specific adsorption membrane (AN69-ST-Heparin Grafted) is used with citrate as an anticoagulant and substitution fluid. CONVEHY uses tools readily available to achieve kidney related and non-related objectives, and it is guided by the monitoring of pathophysiological responses.

Objectives: To compare the response to an AN69-ST-HG membrane when heparin (He, n=5: Standard protocol) or citrate (Ci, n=6: CONVEHY protocol) was used to evaluate whether a larger study into the benefits of this protocol would be feasible.

Materials and methods: In a retrospective pilot study, the benefits of the CONVEHY protocol to manage patients with a DIR in a surgical critical care unit (CCUs) were assessed by evaluating the SOFA (Sequential Organ Failure Assessment) (He 11 ± 2.35; Ci 11 ± 3.63: p=0.54) and APACHE II (He 28.60 ± 9.40; Ci 24 ± 8.46: p=0.93) scores.

Results: Nights in hospital (He 35.2 ± 16.3 nights; Ci 9 ± 2.53: p=0.004), hospital admission after discharge from the CCUs (He 40.25 ± 21.82; Ci 13.2 ± 4.09: p=0.063), patients hospitalised >20 days (He 80%; Ci 0%: p=0.048), days requiring mechanical ventilation (He 16 ± 5.66; Ci 4 ± 1.72: p=0.004), and the predicted (55.39 ± 26.13%) versus real mortality in both groups (9.1%: p=0.004).

Conclusions: The CONVEHY protocol improves the clinical responses of patients with DIR, highlighting the potential value of performing larger and confirmatory studies.

Keywords: AN69-ST-heparin grafted; AN69-ST-heparina anclada; Citrate; Citrato; Daño isquemia-reperfusión; Dysregulated inflammatory response; Haemofiltration; Hemofiltración; Hiperfiltración; Hyperfiltration; Ischaemia-reperfusion injury; Respuesta inflamatoria desregulada.