Does cell-saver blood administration and free hemoglobin load cause renal dysfunction?

Area of Science:

• Nephrology
• Transfusion Medicine
• Surgical Critical Care

Background:

• Intraoperative blood salvage using cell-savers is common practice.
• Free hemoglobin (Hb) released during salvage is a potential nephrotoxic agent.
• The relationship between salvaged blood volume and renal dysfunction requires further elucidation.

Purpose of the Study:

• To evaluate the impact of cell-saver volume and free hemoglobin load on postoperative renal dysfunction.
• To determine if elevated free hemoglobin concentrations correlate with adverse renal outcomes.

Main Methods:

• Retrospective analysis of 125 patients undergoing intraoperative blood salvage from 1992-1998.
• Measurement of free hemoglobin concentration in salvaged blood samples.
• Calculation of total free hemoglobin load per patient.
• Definition of renal dysfunction as a creatinine increase of ≥1.0 mg/dL above baseline.

Main Results:

• Free hemoglobin concentration ranged from 19 to 304 mg/dL (mean 87.5 mg/dL).
• A significant association was found between higher free hemoglobin load and increased prevalence of renal dysfunction (P < 0.001).
• 12% of patients experienced significant postoperative renal dysfunction.

Conclusions:

• Increased free hemoglobin load from cell-saver procedures is associated with postoperative renal dysfunction.
• Establishing policies and limits for maximal free hemoglobin levels during blood salvage is warranted.
• Further research is recommended to define safe thresholds for free hemoglobin exposure.