CVVH versus IHD in patients with multiple organ failure

The place and role of continuous renal replacement therapy (CRRT) has recently been evaluated in comparison with intermittent hemodialysis (IHD) in patients with multiple organ failure (MOF). The emphasis is on removal of a number of inflammatory cytokines, not only correction of azotemia which can be achieved with dialysis.

Patients and methods

The randomized prospective study on 104 patients with MOF investigated circulatory stability, survival after 28 days, and total survival. Intermittent hemodialysis was performed every day, during 3–4 hours with blood flow rate 200–250 ml/min and dialysate flow rate 500 ml/min, using a bio-compatible polysulfone membrane with surface area 1.4–1.6 m², most frequently without heparin utilization. CVVH was procedure of continuous venovenous hemofiltration, where in the first 33 patients 18 ml/kg per hour were replaced (low volume hemofiltration) and, subsequently, 35 ml/kg per hour (high volume hemofiltration). The membrane used for CVVH was of polysulfone. MOF was defined as a severe deterioration of at least two organ systems. Circulatory instability was defined by blood pressure fall up to 10 mmHg or over 10 mmHg.

The etiology of MOF was sepsis (52 patients), septic shock (28 patients) renopulmonary syndrome (five patients), hemorrhagic fever (seven patients), rhabdomyolysis (five patients), and ishemic cardiomyopathy (seven patients).

Results

Comparison of scoring systems of both patient groups showed no statistically significant difference: (HD:HF arithmetic means ± SD) APACHE II₀ (20.3 ± 8.4 vs 21.9 ± 8.8, P = NS), MARSHALL II₀ (8.3 ± 4.0 vs 9.6 ± 3.5, P = NS), SOFA₀ (9.2 ± 4.6 vs 10.6 ± 3.8, P = NS), APACHE II₃ (16.4 ± 7.5 vs 18.3 ± 8.2, P = NS), MARSHALL₃ (7.1 ± 3.8 vs 8.1 ± 3.7, P = NS), SOFA₃ (7.7 ± 4.6 vs 9.3 ± 4.2, P = NS), APACHE II₇ (15.5 ± 8.2 vs 18.2 ± 8.5, P = NS), MARSHALL₇ (6.1 ± 3.9 vs 7.3 ± 4.1, P = NS), SOFA₇ (6.6 ± 4.3 vs 8.5 ± 4.6, P = NS). No statistically significant difference in 28-day survival between IHD and CRRT was seen (23/52 vs 17/52, P = NS). No statistically significant difference in total survival between IHD and CRRT was seen (21/52 vs 15/52, P = NS). Survival of patients on low versus high volume hemofiltration was studied (9/31 vs 6/21, P = NS). The number of hypotensive attacks, defined by blood pressure fall up to and over 10 mmHg in the group of patients on continuous procedures, was not significantly smaller (Rank Sum 2664.5 vs 2795.5, P = NS)

Conclusion

In this randomized prospective study, survival of patients with MOF after 28 days, total survival, and circulatory instability were not significantly related to the type of procedure. In our patients no difference in survival was reached with regard to the use of low volume versus high volume hemofiltration.