Effect of three resuscitative fluid therapy strategies on NT-proBNP concentration in healthy dogs.

OBJECTIVE: To determine if 3 resuscitative fluid therapy strategies increase N-terminal pro-brain natriuretic peptide (NT proBNP) levels in healthy dogs.

DESIGN: Randomized crossover trial.

SETTING: Veterinary teaching hospital.

ANIMALS: Plasma NT proBNP concentrations were measured in 6 healthy purpose-bred dogs that received 3 resuscitative fluid therapy protocols.

MEASUREMENTS AND MAIN RESULTS: Crystalloid, synthetic colloid, or hypertonic saline fluids were administered at resuscitative doses. Blood samples were collected via an indwelling catheter before, and at set time points between 0.5 and 36 h after fluid therapy and analyzed for NT-proBNP. A general linear mixed model was used to estimate the differences in NT-proBNP over time and among treatments. None of the resuscitative fluid therapy protocols caused increases of serum NT-proBNP beyond the previously reported cutoff concentration used to differentiate cardiac versus noncardiac causes of respiratory signs. Dogs receiving crystalloid fluid therapy had the most significant and prolonged increase in serum NT-proBNP concentration above baseline compared to dogs receiving either resuscitative doses of colloids or hypertonic saline.

CONCLUSIONS: Serum NT-proBNP concentration in normal dogs was not increased beyond concentrations previously established to equate to cardiac disease after receiving resuscitative fluid therapy with either a balanced crystalloid solution, hypertonic saline, or a synthetic colloid solution in this study.