Mean filter life span in continuous veno-venous hemofiltration for septic patients

Ioana Ghiţescu¹, Sanda-Maria Copotoiu¹1, Roxana Simona Toma², V.T. Ghiţescu³, Ruxandra Copotoiu¹

1 Universitatea de Medicina şi Farmacie, Disciplina ATI, Clinica ATI I; Spitalul Clinic Judeţean de Urgenţă Tg. Mureş
2 Institutul de Urgenţă de Boli Cardiovasculare şi Transplant Tg. Mureş, Secţia ATI
3 Institutul Medico-Militar, Tg. Mureş

Abstract

Background: Coagulation disorders in septic patients treated with continuous veno-venous hemofiltration (CVVH) are a possible cause of thefrequent clotting of the filter and the reduction in mean filter life span (MFL).

Objective: To establish the statistical correlation between MFL and the diagnosis of severe sepsis and/or septic shock.

Method: Retrospective analysis of 77 patients treated with CVVH, using the same technique and anticoagulation protocol. We identified the following groups of patients: A (38 without sepsis), S (39 with sepsis), the last one divided in subgroup S1 (22 with severe sepsis) and S2 (17 with septic shock). We calculated and compared heparin doses, anticoagulation targets (AT) and MFL in all groups (t- Student, Mann-Whitney; statistical significance  p value < 0.05).

Results: No differences were observed between A and S groups for AT (aPTT: 2.11 × normal value vs 2.09 × normal value, p = 0.815), nor for MFL (23.44 h versus 23.09 h, p = 0.554). Group A received higher heparin dosis than group S (9.084 UI/kg/h vs 6.436 UI/kg/h, p = 0.012) for reaching similar AT. In subgroups S1 and S2 we found no differences for AT (aPTT 1.95 × normal value vs 2.23 × normal value, p = 0.201), nor for heparin dosis (5.736 UI/kg/h vs 7.431 UI/kg/h, p = 0.254), but we found differences in MFL (25.49 h vs 19.98 h, p = 0.046).

Conclusions: For similar AT and MFL patients with sepsis need more heparin for maintaining the filter patency than non-septic patients. MFL is significantly reduced in septic shock as compared with severe sepsis patients, despite the use of same AT and heparin dosis.

Key words: hemofiltration, filter life span, sepsis