Effect of hypertonic dextran on intestinal mucosal perfusion during porcine endotoxin shock

Introduction

Mucosal hypoperfusion during sepsis might impair the epithelial barrier function leading to translocation of luminal bacterial products and further aggravation of the septic state. Supporting perfusion of the intestinal mucosa could ameliorate barrier dysfunction. The microcirculatory effects of hypertonic vs isotonic colloid volume resuscitation during sepsis have with respect to mucosal perfusion been sparsely reported.

Aim

To evaluate the effects of hypertonic vs. isotonic colloid volume resuscitation to maintain mucosal perfusion during porcine endotoxemia.

Interventions

Fasted, anesthetised, mechanically ventilated pigs (30.6 ± 2.0 kg, mean ± SEM) received infusion of LPS (EC seropype 0111: B4) during 2 h to establish septic shock and were then observed for another 90 min. After 1 h of LPS infusion, animals were randomized to resuscitation (4 ml/kg for 10 min) with isotonic dextran (Macrodex^®, ISO, n = 6 or hypertonic dextran (RescueFlow^®, HYPER, n = 6).

Measurements and main results

Mean arterial pressure (MAP), cardiac output (CO), portal venous blood flow (QPV), mucosal perfusion by laser-Doppler flowmetry (LDF) and tonocapnometry (giving regional prCO₂ and the pCO₂ gap from paCO₂) were assessed. Statistical analyses were made by ANOVA. ^§ P < 0.05 vs. 60 min. ^* P < 0.05 vs. ISO.

LPS-infusion resulted in hypodynamic shock after 60 min with no intergroup differences. Resuscitation with HYPER improved the mesenteric and specifically the mucosal circulation, whereas ISO was ineffective in this respect. HYPER also tended to improve CO while this effect failed to gain statistical significance (P = 0.11).

Conclusion

Volume resuscitation with hypertonic colloid proved superior to isotonic colloids to support intestinal and in particular mucosal perfusion during hypodynamic septic shock. The results indicate that hypertonic colloids might be of special value to support mucosal perfusion and thereby possibly barrier function in sepsis.

Table are absolute changes