The role of fluid replacement in acute endotoxin shock

Summary

A hyperdynamic circulatory state is the characteristic feature of septic shock in its early phase. Survival may be increased if the transition of the high flow state into the hypodynamic, low flow state can be prevented by well-controlled volume support using pulmonary capillary wedge pressure as a readily available clinical guideline. In our animal study the maintenance of cardiac output in endotoxaemia prevented the development of low flow/high resistance shock. The lungs ventilatory function was only moderately affected with no significant difference between volume substitution with either dextran 60 or Ringer’s lactate. However, we found that vital organs suffer microcirculatory disturbances early in the initial phase of endotoxaemia. Impairment of regional and intra-organ blood flow distribution was more pronounced in the animals treated with Ringer’s lactate. Dextran 60 appeared to prevent underperfusion of vital organs by maintaining vascular volume at a constant colloid osmotic pressure; no signs of tissue overhydration were observed.