Early isovolaemic haemofiltration in oliguric patients with septic shock

Objective: To evaluate the effects of early short-term, isovolaemic haemofiltration at 45 ml/kg/h on physiological and clinical outcomes in patients with septic shock. Design: Retrospective study before and after a change of unit protocol (study period 8 years). Setting: Intensive care unit of metropolitan hospital. Patients: Eighty patients with septic shock. Interventions: Introduction of a new septic shock protocol based on early isovolaemic haemofiltration (EIHF). In the pre-EIHF period (before), 40 patients received conventional supportive therapy. In the post-EIHF period (after), 40 patients received EIHF at 45 ml/kg/h of plasma-water exchange over 6 h followed by conventional continuous venovenous haemofiltration (CVVH). Anticoagulation policy remained unchanged. Measurements and main results: The two groups were comparable for age, gender and baseline APACHE II score. Delivered haemofiltration dose was above 85% of prescription in all patients. PaO₂/FiO₂ ratio increased from 117±59 to 240±50 in EIHF, while it changed from 125±55 to 160±50 in the control group ( p <0.05). In EIHF patients, mean arterial pressure increased (95±10 vs 60±12 mmHg; p <0.05), and norepinephrine dose decreased (0.20±2 vs 0.02±0.2 µg/kg/min; p <0.05). Among EIHF patients, 28 (70%) were successfully weaned from the ventilator compared with 15 (37%) in the control group ( p <0.01). Similarly, 28-day survival was 55% compared with 27.5% ( p <0.05). Length of stay in the ICU was 9±5 days compared with 16±4 days ( p <0.002). Conclusions: In patients with septic shock, EIHF was associated with improved gas exchange, haemodynamics, greater likelihood of successful weaning and greater 28-day survival compared with conventional therapy.