Acid–Base Changes in Canine Neonates Following Normal Birth or Dystocia

Abstract

There are limited data concerning blood gas parameters in neonatal dogs. Knowledge of the normal physiology may facilitate effective therapeutic intervention and potentially reduce neonatal mortality. This study examined acid-base parameters in pups born at normal parturition (n = 27) compared with those born after obstetrical assistance or caesarean operation (n = 13) and those born following oxytocin (OXY) administration for treatment of uterine inertia (n = 11). Pups were subjected to an objective scoring method of neonatal health adapted from use in humans (the Apgar score) at birth and again at 5 and 60 min after birth. Venous blood samples were collected at 5 and 60 min after birth for evaluation of blood gas parameters. At birth, all pups had low Apgar scores and a mixed acidosis. The base excess was lowest for pups delivered after OXY administration. The Apgar score improved for all pups after 5 min of birth and there was an improvement in carbon dioxide tension, base excess and venous blood pH at 1 h, although in all pups a metabolic acidosis persisted. These data provide an important insight into neonatal physiology and the variability of blood gas parameters in pups born at normal and abnormal parturition and provide the basis for clinical decision making following dystocia.

Effect of intrapartum fetal stress associated with obstetrical interventions on viability and survivability of canine neonates

“…This result indicates that the puppies that were dead were severely stressed due to hypoxia produced as a result of combined effect of anesthetics used in cesarean section and ecbolics used during AW [15]. …”

Prenatal and Neonatal Adaptations with a Focus on the Respiratory System

“…When analysing the Apgar scores of canines, Lúcio et al. () observed depression of the vital functions immediately after birth in response to the transition between foetal and extrauterine life. However, recovery was appropriate at 5 min of life, and high scores persisted up to 1 h after birth.…”

“…According to pH measurements, canine neonates exhibit acidosis at birth that is both metabolic (low base excess and HCO 3 − ) and respiratory (high PCO 2 ), which is called mixed acidosis (Lúcio et al. ). At birth, pulmonary expansion begins progressively, which does not allow gas exchange to attain immediate balance and thus favour the development of the mixed acidosis observed at this stage (Crissiuma et al.…”

“…One hour after birth, canine puppies still exhibited acidosis because despite a significant increase, the pH values remained below the reference values (Lúcio et al. ). The assessment of the base excess and HCO 3 − variables at this point shows that the metabolic component has not reached its balance.…”

“…However, gas exchange balance is not achieved immediately, and newborns undergo a period of physiological hypoxia that increasingly worsens throughout the first hour of life (Lúcio et al. ).…”