Prophylactic hemofiltration in severely traumatized patients: effects on post-traumatic organ dysfunction syndrome

To evaluate the effects of prophylactic veno-venous hemofiltration (CVVH) in the absence of renal failure on multiple organ dysfunction syndrome after severe multiple trauma.

Prospective, randomized study.

Intensive care unit (ICU) in a university hospital.

Twenty-four patients with severe multiple trauma (injury severity score > or = 27), no renal failure on admission and no contraindication for moderate heparinization.

Twelve patients received conventional treatment while 12 patients were treated additionally with isovolemic CVVH for 5 days starting within 24 h following trauma. Signs of organ dysfunction were assessed daily including monitoring of systemic hemodynamic by means of pulmonary artery catheterization during the first 5 days after trauma.

Prophylactic CVVH did not affect the overall severity of organ dysfunction as assessed by MOF or APACHE II scores. However, the pattern of impaired organ systems was influenced by CVVH: while the post-traumatic decrease in platelet count in patients subjected to CVVH was more pronounced than in controls (e.g. day 4: control: 115,080 +/- 15,087, CVVH: 57,383 +/- 4,201 microliters-1; p < 0.05) the development of hyperdynamic circulatory failure was simultaneously attenuated, as reflected by a limited increased in cardiac output and an attenuated decrease in systemic vascular resistance and oxygen extraction ratio (e.g. systemic vascular resistance on day 4: control: 624.3 +/- 46.17, CVVH: 842.7 +/- 79.24 dyn.s.cm-5; p < 0.005).

CVVH blunts the cardiovascular response to multiple trauma and increases tissue oxygen extraction. However, the concomitant decrease in platelet counts represents a limitation for the use of prophylactic CVVH in surgical patients.