Effects of hypertonic saline solution and pentoxifylline on rat mesenteric microcirculation after hemorrhagic shock/reperfusion followed by cecal ligation/puncture: an intravital microscopic study

Abstract

Objective Hemorrhagic shock/reperfusion followed by sepsis triggers systemic microcirculatory disturbances that may induce multiple organ failure. The present in-vivo study evaluated the effects of hypertonic saline solution (HSS) (7.5%, 4 ml/kg) and pentoxifylline (PTX) (4 mg/kg) on mesenteric microcirculation in double-injured rats. Methods Thirty-three anesthetized Wistar rats (~250 g) were randomly assigned to: (1) SHAM: no injury group; (2) HSS: hemorrhagic shock/reperfusion with HSS; (3) LR: hemorrhagic shock/reperfusion with lactated Ringer's solution (LR), three times shed blood volume; (4) HSS + PTX: hemorrhagic shock/reperfusion with HSS associated with PTX; and (5) LR + PTX: hemorrhagic shock/reperfusion with LR associated with PTX. The animals were submitted to cecal ligation/puncture (second injury). Results Leukocyte – endothelium interactions (Table 1) were assessed by intravital microscopy at mesenteric postcapillaric venules (~21.07 μm diameter). Table 1 Leukocyte – endothelial interactions in mesenteric postcapillaric venules Rollers Adherent cells Migrated cells Total white blood Group n (10 min) (100 μm venule length) (5,000 μm2) (cells/mm3) SHAM 6 96 ± 12 3 ± 1 2 ± 1 12,367 ± 2,641 LR 7 207 ± 19a 17 ± 1a 17 ± 1a 16,771 ± 5,703a HSS 8 108 ± 16 9 ± 3c 12 ± 3c 12,388 ± 6,629 HSS + PTX 7 102 ± 26 6 ± 1b,c 6 ± 1b,c 10,757 ± 2,483 LR + PTX 5 115 ± 20 7 ± 1c 7 ± 1b,c 11,650 ± 1,570 a P < 0.001 vs other groups, c P < 0.001 vs SHAM, c P < 0.001 vs HSS. Conclusion The in-vivo observation of the rat mesenteric microcirculation showed that, in a double-injury model, reperfusion of the animals with HSS and PTX did attenuate the inflammation response compared with LR-reperfused animals.