Intravenous fluid therapy

(Redirected from Volume repletion)

This page is for adult patients. For pediatric patients, see: Intravenous fluid therapy (peds) or critical care quick reference for bolus doses by weight.

Background

Composition of Different Intravenous Fluids

Fluid [1] Osm Na Cl Glucose(g/L) pH Buffer K Ca Mg
Plasma 289 140 103 7.4 HCO3 22-32 4 5 2
Normal Saline (NS) 308 154 154 0 5.0 0 0 0 0
D5NS 560 154 154 50 0 0 0
Lactated Ringers 273 130 109 0 6.5 Lactate 28 4 3 0
Plasmalyte 295 140 98 0 5.0 Gluconate 23/Acetate 27 5 0 3
D5 1/2NS 406 77 77 500 4.5 0 0 0 0
D5Water 252 0 0 50
5% Albumin 309 130-160 130-160 6.4-7.4 <1

Total Body Water

  • Total Body Water (TBW) = 0.6 x weight (kg)
    • Of which, 2/3 is intracellular and 1/3 extracellular
      • 1/4 of extracellular is vascular

Acute Repletion (Bolus)

Maintenance Fluids

  • Insensible losses = 300-400 cc/m2/d
  • Adult Standard: D5 0.45%NS at 75-125 mL/hr + 20meq/L of KCl
  • Deficit: % dehydration x baseline weight
  • Daily volume needed = maintenance + deficit - fluid already given (i.e. boluses)
    • Hourly rate daily volume/24 hr
      • (or correct 1/2 of deficit in first 8 hr, remainder in next 16)

Electrolytes

  • Maintenance Na = 3 mEq/kg/d; K = 2 mEq/kg/d
  • Deficit = [desired - measured mEq/L] x fD x wt (kg)
  • fD (distribution factor) Na = 0.6, K = 0.6, Cl = 0.2-0.3, HCO3 = 0.5
  • (Maintenance + deficit)/daily volume = concentration of electrolyte in fluid to be given
  • 4mL/kg of H2O lost, ups Na by 1meq

See Also

External Links

References

  1. Paucis Verbis: Composition of intravenous fluids. http://www.aliem.com/paucis-verbis-composition-of-intravenous-fluids/ Published January 3, 2013. Accessed August 29, 2015