Continuous fluid resuscitation for treatment of uncontrolled hemorrhagic shock following massive splenic injury in rats

We have previously observed that bolus fluid resuscitation in uncontrolled hemorrhagic shock induced by solid organ injury leads to increased blood loss and mortality. In the present investigation, we studied the effect of continuous fluid resuscitation on the hemodynamic response and survival following massive splenic injury (MSI) in rats. The animals were randomized into 11 groups: group 1, sham-operated; group 2, MSI untreated; group 3, MSI treated with 17.5 mL/kg/h of Ringer's lactate (RL) solution (RL-17.5); group 4, MSI treated with 35 mL/kg/h RL (RL-35); group 5, MSI treated with 70 mL/kg/h RL (RL-70); group 6, MSI treated with 7.5 mL/kg/h of 7.5% NaCl (HTS-7.5); group 7, MSI treated with 15 mL/kg/h of 7.5% NaCl (HTS-15); group 8, MSI treated with 30 mL/kg/h of 7.5% NaCl (HTS-30); group 9, MSI treated with 7.5 mL/kg/h 6% hydroxyethyl starch (HES-7.5); group 10, MSI treated with 15 mL/kg/h 6% hydroxyethyl starch (HES-15); and group 11, MSI treated with 30 mL/kg/h 6% hydroxyethyl starch (HES-30). MSI in untreated group 2 was followed by a fall of mean arterial pressure (MAP) to 50.1 +/- 6.7 mmHg (P < 0.001) in 15 min. Mean survival time (MST) was 99.5 +/- 16.6 min, and total blood loss (TBL) was 37.8% +/- 2.6% of blood volume. Fluid treatment with increasing volumes of RL in groups 3, 4, and 5 was followed by a gradual increase in TBL compared with untreated animals, and MST remained unchanged. Increasing volumes of HTS infusion in groups 6, 7, and 8 was also followed by incease in TBL, but MST remained unchanged except for an increase to 123.0 +/- 20.5 min (P < 0.05) in group 6. Increasing volumes of HES in groups 9, 10, and 11 was also followed by increase in TBL, but MST remained unchanged. In conclusion, continuous infusion of LR, HTS, and HES following massive splenic injury resulted in a significant increase in intra-abdominal bleeding, but survival time in the first hour following injury remained unchanged in contrast to bolus fluid infusion, which increases early mortality.