The nurse is caring for a 10-year-old on admission to the burn unit. One assessment parameter that will indicate that the child has adequate fluid replacement is:
A. Urinary output of 30 ml per hour
B. No complaints of thirst
C. Increased hematocrit
D. Good skin turgor around burn
Correct Answer: A. Urinary output of 30 ml per hour
For a child of this age, this is adequate output, yet does not suggest overload. Disruption of sodium-ATPase activity presumably causes an intracellular sodium shift which contributes to hypovolemia and cellular edema. Heat injury also initiates the release of inflammatory and vasoactive mediators. These mediators are responsible for local vasoconstriction, systemic vasodilation, and increased transcapillary permeability. Increase in transcapillary permeability results in a rapid transfer of water, inorganic solutes, and plasma proteins between the intravascular and interstitial spaces.
Option B: Relying on the client’s thirst would not create accurate results. The steady intravascular fluid loss due to these sequences of events requires sustained replacement of intravascular volume in order to prevent end-organ hypoperfusion and ischemia.
Option C: An increase in hematocrit suggests vascular space fluid losses. Reduced cardiac output is a hallmark in this early post-injury phase. The reduction in cardiac output is the combined result of decreased plasma volume, increased afterload and decreased cardiac contractility, induced by circulating mediators.
Option D: A good skin turgor is not an accurate indicator of adequate fluid replacement. The goal of fluid management in major burn injuries is to maintain the tissue perfusion in the early phase of burn shock, in which hypovolemia finally occurs due to steady fluid extravasation from the intravascular compartment.