Bolus versus continuous fluid resuscitation and splenectomy for treatment of uncontrolled hemorrhagic shock after massive splenic injury.

Abstract

Using a standardized model of uncontrolled hemorrhagic shock induced by massive splenic injury (MSI), we compared bolus infusion of Ringer's lactate (RL) and hypertonic saline (HTS), combined with splenectomy, to continuous infusion of these solutions and splenectomy in rats. Animals were randomized into six groups: group 1 (n = 8) was sham-operated. In group 2 (n = 8), MSI was untreated, and splenectomy was performed after 45 minutes. In group 3 (n = 8), MSI was treated after 15 minutes by a bolus of 40 mL/kg Ringer's lactate (LVRL-b), and splenectomy after 45 minutes. In group 4 (n = 8), MSI was treated by a bolus of 5 mL/kg 7.5% NaCl (HTS-b) and splenectomy. In group 5 (n = 8), MSI was treated by continuous infusion of 40 mL/kg/h Ringer's lactate (LVRL-c) and splenectomy. In group 6 (n = 8), MSI was treated by a continuous infusion of 5.0 mL/kg/h 7.5% NaCl (HTS-c) and splenectomy. After MSI, mean arterial pressure decreased in untreated group 2 from 119.2 +/- 5.6 mm Hg to 39.9 +/- 9.7 mm Hg (p < 0.001) in 60 minutes. Total blood loss (TBL) was 20.9 +/- 4.4% of blood volume and mean survival time (MST) was 177.1 +/- 21.3 minutes. LVRL-b infusion was followed by an early increase in mean arterial pressure from 67.9 +/- 7.2 mm Hg to 91.5 +/- 9.5 mm Hg (p < 0.01) after 30 minutes and then rapidly dropped to 34.4 +/- 5.7 mm Hg (p < 0.01) after 60 minutes. TBL was 38.8 +/- 4.7% (p < 0.001) and MST was 197.5 +/- 21.9 minutes. HTS-b infusion was followed by TBL of 28.1 +/- 5.3% and MST of 212.5 +/- 19.5 minutes. LVRL-c infusion was followed by TBL of 27.3 +/- 4.1% and MST of 219.6 +/- 12.9 minutes (p < 0.05). HTS-c infusion was followed by TBL of 23.9 +/- 1.6% and MST of 227.5 +/- 9.4 minutes (p < 0.03). Continuous infusion of RL combined with splenectomy was followed by significantly less bleeding than bolus infusion of RL and improved survival time compared with untreated animals. Continuous HTS infusion and bolus infusion of HTS with splenectomy resulted in minimal blood loss and improved survival compared with untreated animals. No significant difference in blood loss or survival time was observed between bolus and continuous HTS infusion.