Effects of two oral electrolyte solutions in healthy newborn lambs.

This study aimed to evaluate the effects of two oral electrolyte solutions (OES), commercialized for the hydration of calves, on the water, electrolyte, and acid-base balance of newborn lambs. Twenty healthy crossbred Santa Inês lambs, 10 days old, 4-5 kg of body weight (BW), and fed on mother's milk, were included. The OES tested were slightly hyposmolar (OES 1: 279 mOsm/L; and OES 2: 283 mOsm/L) and had an alkalizing potential with an effective strong ion difference (SID3) of 76 mmol/L (OES 1) and 58 mmol/L (OES 2). In a crossover design, all lambs received the two OES, one at a time, with an interval of 7 days. On the day of treatment, the lambs received a volume corresponding to 5% of BW administered by esophageal tube at 0 and 6 h. Physical examinations were performed and venous blood samples were taken at 0, 6, 12, 24, and 48 h. Packed cell volume, total plasma protein, pH, partial pressure of carbon dioxide, bicarbonate ion, base excess, sodium (Na+), potassium, chloride (Cl-), SID3, L-lactate, glucose, anion gap, total concentration of non-volatile weak acids, and percentage change in plasma volume were measured. Data were analyzed by two-way repeated measures ANOVA. OES caused iatrogenic imbalances characterized by expansion of plasma volume, change in the Na+ and Cl- ratio with increase in plasma SID3, and strong ion metabolic alkalosis. These imbalances were mostly reversed 24 h after the start of treatment and did not differ (P > 0.05) between the two tested OES. The absence of side effects indicates that the tested commercial OES are safe for use in newborn lambs. Further studies are needed to prove the therapeutic efficacy of these OES in dehydrated sick lambs with metabolic acidosis.

A velocidade de infusão da solução poli-iônica intravenosa contendo 84mEq/L de lactato determina a intensidade do efeito alcalinizante em equinos / The intravenous polyionic solution with 84mEq/L of lactate infusion rate determines the intensity of the alkalizing effect in horses

O objetivo deste trabalho foi verificar os efeitos da solução poli-iônica intravenosa contendo 84mEq/L de lactato (L84) sobre os equilíbrios hidroeletrolítico e ácido-base de equinos, quando administrada de forma rápida ou lenta. Cinco equinos sadios adultos receberam a infusão contínua intravenosa da L84, em volume correspondente a 10% do peso corporal, em duas ocasiões: a) infusão rápida (16,66mL/kg/h) durante seis horas; b) infusão lenta (8,33mL/kg/h) durante 12 horas. Amostras de sangue venoso foram colhidas ao início da infusão (hora zero) e três, seis, nove, 12 e 24 horas após, e amostras de urina nas horas zero, seis, 12 e 24. Determinaram-se pH (sanguíneo e urinário), pCO2, HCO3 -, BE, PPT, lactato L, Na+, K+, Cl-, AG, SID, Atot, VVP, densidade urinária e excreções fracionadas urinárias de lactato L, Na+, K+ e Cl-. A L84 provoca efeito alcalinizante iatrogênico de menor magnitude quando administrada de forma lenta, porque os mecanismos renais, atuantes durante o período de infusão, promovem a correção gradativa do desequilíbrio. Pode-se concluir que a infusão de forma lenta da solução L84 em equinos é recomendável nos casos em que se suspeite de acidose metabólica e não seja possível quantificar o grau do desequilíbrio.(AU)

The aim of this study was to investigate the effects of an intravenous polyionic solution containing 84mEq/L of lactate (L84) on the hydroelectrolyte and acid-base balances when administered quickly or slowly in horses. Five healthy adult horses received the L84 solution, in a volume corresponding to 10% of BW, by continuous intravenous infusion, in two instants: a) rapid infusion (16.66mL/kg/h) during 6 hours; b) slow infusion (8.33mL/kg/h) during 12 hours. Venous blood samples were taken at the beginning of the infusion (hour 0) and 3, 6, 9, 12, and 24 hours after. Urine samples were taken at 0, 6, 12, and 24h. pH (blood and urine), pCO2, HCO3-, BE, TPP, L-lactate, Na+, K+, Cl-, AG, SID, Atot, PVV, urine specific gravity, and L-lactate, Na+, K+, and Cl- renal fractional clearance were determined. The L84 solution causes lower magnitude alkalizing effect when administered slowly, due to the gradual correction of the iatrogenic imbalance by the kidneys during the infusion period. The L84 solution infused at a low rate in horses could be recommended in cases where metabolic acidosis is suspected and it is not possible to quantify the imbalance degree.(AU)