Resuscitation of severe thermal injury with hypertonic saline dextran: Effects on peripheral and visceral edema in sheep

Background: Edema of tissue not directly injured by heat is a common complication after resuscitation of burn shock. Hypertonic 7.5% NaCl 6% dextran (HSD) infusion reduces early fluid requirements in burn shock, but the effects of HSD on peripheral and visceral tissue edema are not well-defined. Methods: We measured the microcirculatory absorptive pressures of burned and nonburned skin and tissue water content of skin and other tissues in anesthetized sheep after 70% to 85% total body surface area scald and resuscitation, Fluid infusion was initiated 30 minutes after injury using 10 mL/kg HSD (n = 11) or lactated Ringer's (LR) (n = 12), with infusion rates titrated to restore and maintain preburn oxygen delivery (D-O2). Thereafter, both groups received LR infusions as needed to maintain D-O2 until the study's end at 8 hours. Colloid osmotic pressure was measured in plasma, and combined interstitial colloid osmotic and hydrostatic pressures were measured in skin. Results:Both treatments successfully restored D-O2, but fluid requirements were less with the HSD group than with the LR group (43 +/- 19 mL/kg vs, 194 +/- 38 mL/kg, respectively, p < 0.05), The peripheral and visceral tissue water contents at 8 hours postinjury until the end of the study in both burn groups were significantly higher than in nonburn controls. However, HSD-treated sheep had significantly less water content in the colon (<down arrow> 28%), liver (down arrow 9%), pancreas (down arrow 55%), skeletal muscle (down arrow 21%), and nonburned skin (down arrow 12%) compared with LR-treated sheep (p < 0.05 for each). HSD-treated sheep maintained significantly higher (3 to 5 mm Hg) plasma colloid osmotic pressure than LR-treated sheep. Conclusion: There were no observed differences in edema in burn skin between the two treatment groups. The early volume-sparing effect of HSD and reduction in tissue edema are likely attributed to an increased extracellular osmolarity and a better maintenance of the plasma. oncotic pressure.