Subcutaneous and liver tissue oxygen tension in hemorrhagic shock: an experimental study with whole blood and two colloids.

Because it is difficult to verify the efficacy of hemorrhagic shock treatment, we compared subcutaneous O2 tension (PscO2) with liver oxygenation in efforts to correct shock in piglets with two different colloids, hydroxyethyl starch (HES-120) and dextran-70. Nineteen animals were bled to shock and the shed blood was retransfused in the control group. Liver oxygenation was measured directly by means of a silicone tube used as a tonometer, and indirectly by calculating liver O2 consumption (VO2). PscO2 was monitored with a needle electrode. The two colloid groups were compared by measuring plasma lactate, and the plasma colloid osmotic pressure (COPp). PscO2 followed closely the changes in liver tissue PO2 during the experiment; it seems to be a useful tool in estimating volume filling during the treatment of hemorrhagic shock. A wider variation was noted in calculated liver VO2 compared with hepatic venous PO2 or liver tissue PO2. Despite the fact that COPp increased to a higher level after the administration of dextran, HES proved to be at least as effective as dextran in restoring mean arterial pressure, cardiac output, liver oxygenation, PscO2, arterial pH, arterial plasma lactate, and liver lactate uptake.