Comparison of acid-base and electrolyte changes following administration of 6% hydroxyethyl starch 130/0.42 in a saline and a polyionic solution in anaesthetized dogs.

OBJECTIVE

To evaluate the effects of a 6% hydroxyethyl starch (130/0.42) in either a buffered, electrolyte-balanced (HES-BAL) or saline (HES-SAL) carrier solution on electrolyte concentrations and acid-base parameters in healthy anaesthetized dogs.

STUDY DESIGN

Prospective randomised clinical study.

ANIMALS

A group of 40 client-owned dogs undergoing general anaesthesia for elective surgical procedures or diagnostic imaging.

METHODS

During anaesthesia, dogs were intravenously administered 15 mL kg of either HES-SAL (n = 20) or HES-BAL (n = 20) over 30-40 minutes. Jugular blood samples were analysed before (T) and 5 minutes (T), 1 hour (T) and 3 hours (T) after fluid administration. Sodium, potassium, chloride, ionised calcium, phosphate, albumin, pH, venous pCO, base excess (BE), bicarbonate and anion gap were determined and strong ion difference (SID) and total quantity of weak nonvolatile acids were calculated for each time point.

RESULTS

Chloride was significantly increased at T, T and T compared with T after HES-SAL, and was significantly greater after HES-SAL than after HES-BAL at T (p = 0.042). Ionised calcium was significantly decreased at T compared with T after HES-SAL, and was significantly lower after HES-SAL than after HES-BAL at T (p < 0.001). Bicarbonate was significantly lower after HES-SAL than after HES-BAL at T (p = 0.004) and T (p = 0.032). BE was significantly lower after HES-SAL than after HES-BAL at T (p < 0.001) and T (p = 0.007). SID was significantly decreased after HES-SAL at T and T compared with T, and was significantly lower after HES-SAL than after HES-BAL at T (p = 0.027). Mean electrolyte and acid-base parameters remained within or marginally outside of reference intervals.

CONCLUSIONS AND CLINICAL RELEVANCE

Changes in both groups were minor and short-lived with either fluid in healthy individuals, but might become clinically relevant with higher fluid doses or in critically ill dogs.