Electrolyte, Blood Gas and Electrocardiographic Profile of Neonatal Foals in the First 48 Hours of Life

Author(s)

Salgueiro Cruz, Raissa Karolliny ^[1] ; Alfonso, Angelica ^[1] ; Gomes Lourenco, Maria Lucia ^[1] ; Vela Ulian, Carla Maria ^[1] ; Sudano, Mateus Jose ^[2] ; Oba, Eunice ^[3] ; Padovani, Carlos Roberto ^[4] ; Rodrigues Ramos, Paulo Roberto ^[5] ; Chiacchio, Simone Biagio ^[1]

Affiliation

^[1] Sao Paulo State Univ UNESP, Dept Vet Sci, Sch Vet Med & Anim Sci, BR-18 61897 Botucatu, SP - Brazil

^[2] Fed Univ Pampa, Lab Genet & Anim Breeding, Uruguaiana, RS - Brazil

^[3] UNESP, Dept Anim Reprod & Vet Radiol, Inst Biosci, Botucatu, SP - Brazil

^[4] UNESP, Dept Biostat, Inst Biosci, Botucatu, SP - Brazil

^[5] UNESP, Dept Phys & Biophys, Inst Biosci, Botucatu, SP - Brazil

• Document type: Journal article
• Source: Acta Scientiae Veterinariae; v. 43, NOV 10 2015.
• Web of Science Citations: 2

Abstract

Background: The neonatal period is characterized as a physiological and metabolic adaptation phase, when organic systems need to face new challenges from extra uterine life. The knowledge in physiology, the evaluation of the newborn vigor and a fast intervention regarding to resuscitation, are essentials to decrease neonatal mortality. The aim of this study is to improve the understanding about clinical and laboratory evaluations of newborn foals through the determination of preventive or corrective methods, observe changes and describe the electrolytic blood gas and electrocardiographic profiles of Paint Horse foals in their first 48 h of life. Material, Methods \& Results: Twenty foals born in eutocia were evaluated at birth, 4, 8, 12, 16, 20, 24, 36 and 48 h thereafter. Clinical examinations (heart rate, respiratory rate and temperature), blood gas and electrocardiography were performed in all moments. No significant differences were observed in blood gas parameters during the analysis. Significant increases (P < 0.001) occurred in body temperature at birth, at 20 h and 36 h after foaling. The animals showed significant decreases in anion gap at birth, at 16 h and 24 h (P < 0.01); in sodium levels from birth to 20 h, and at 24 h (P < 0.001) and potassium levels between 4 h and 48 h after birth (P < 0.05); these concentrations were associated with variations in the electrocardiographic parameters. The electrocardiogram resulted in progressive decreases in QT interval, and in lengh and amplitude of T wave. There were negative correlations between QT interval and T wave amplitude at 16 h (rho = -0.56, P = 0.009), the QT interval and cell volume at 24 h (R = -0.48, P = 0.03), the QT interval and hemoglobin level at 24 h (R = -0.48, P = 0.03), and the QT interval and temperature at 36 h (R = -0.057, P = 0.007). There were negative correlations for Potassium at birth (R = -0.052, P = 0.01) and at 20 h (rho = -0.49, P = 0.02), and there was a positive correlation for anion gap at 20 h (rho = 0.52, P = 0.01). There was a negative correlation between T wave amplitude and Sodium at 12 h after birth (R = -0.47, P = 0.03). Sinus rhythm was the main one, 85% of the animals presented this cardiac rhythm, followed by sinus tachycardia, presenting in 45% of the animals, and ventricular tachycardia in 15% of the animals. Premature ventricular contractions were observed in 10% of the foals. Discussion: It was possible to set correlations between electrolytic levels and electrocardiographic parameters. The metabolic changes observed in this study can lead to variations in electrical heart activity, as the sinus arrhythmia and sinus tachycardia. The systemic metabolic changes can implicate, directly or indirectly, in changes at cardiovascular function, compromising the myocardial integrity. The main heart rhythm in our study was sinus rhythm, which is considered physiological for foals. However, there are few data about equine neonatology that report the importance of cardiac changes in the performance of the future athlete horse. The presence of sinus arrhythmia and sinus tachycardia in foals was described in previous studies, although these arrhythmias are common during the period of neonatal adaptation. These results are also associated with the neonatal adaptation, making it necessary to develop new studies to establish references values applicable to this period and to different breeds. The electrolyte values decreased over the first 48 h of life, suggesting that electrolyte homeostasis only occurrs after 48 h of life. (AU)

• FAPESP's process: 12/24845-7 - Evaluation of neonatal vitality, blood gas analisys and electrocardiography in horses Quarter Horse Breed
• Grantee: Simone Biagio Chiacchio
• Support Opportunities: Regular Research Grants