Canis ISSN: 2398-2942

Fluid therapy: for burns

Contributor(s): Elisa Mazzaferro, Sheilah Robertson, Claire Waters

Pathophysiology

  • Severe burn → significant increase in vascular endothelium permeability throughout the body due to release of inflammatory mediators from burn site.
  • Loss of plasma proteins from vascular space results in reduced plasma oncotic pressure and fluid shift from vascular space to interstitium.
    As much as 50% of plasma water may be lost from the circulation 2 h after severe burn injury.
  • Hyperkalemia Hyperkalemia , may result from K+ release from damaged cells.
  • Destruction of red blood cells occurs in the post-burn period because of increased fragility and morphological changes.
  • Metabolic acidosis Acid base imbalance is common following severe burns.

Treatment

Generally avoid colloids or plasma in the immediate post-burn period as they will be lost from the circulation to the interstitium.
  • It is very difficult to estimate fluid deficit. Therefore, give a balanced crystalloid solution intravenously and vary rate according to response.
  • If the dog has life-threatening shock Shock then it may benefit from rapid infusion of a crystalloid/colloid or crystalloid/hypertonic saline mixture.
    For composition of solutions see Parenteral fluids comparison tableParenteral fluid comparison table Links.
  • Hypokalemia may occur a day or two into the post-burn period because of increased renal excretion.
    Monitor serum potassium Blood biochemistry: potassium at least daily following severe burns and replace accordingly.
  • Monitor total protein and packed cell volume, colloid oncotic pressure.
  • Colloids or blood products may be required from 2 days post-burn.
  • If available, monitor blood gases and supplement bicarbonate Sodium bicarbonate - if pH <7.1. In the absence of this facility, it may be beneficial to add 5 MEq/l HCO3- to fluids for patients with severe burns.
  • Monitoring central venous pressure Blood pressure: direct measurement and urine output Anesthetic monitoring: urine output provides a good guide as to the adequacy of the fluid therapy.


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