Anesthesia for non-obstetric surgery during late term pregnancy in mares.
Abstract: Submitting late-term pregnant mares to anesthesia for non-obstetric surgery raises concerns about the survival of the mother and fetus. This study aimed to evaluate and describe transient maternal and fetal hemodynamic changes during general inhalation anesthesia in mares during the last month of gestation. Nine adult mares in the last month of gestation were subjected to general inhalation anesthesia and dorsal recumbency for 90 minutes. Trans-anesthetic vital parameters, arterial hemogasometry, cardiac output, pulmonary arterial pressure, central venous pressure, and fetal heart rates were assessed at defined intervals. During various timespans of the anesthetic procedure, the mares demonstrated an increase in heart rate, mean arterial pressure, and diastolic pressure as well as a decrease in temperature. Additionally, arterial hemogasometry indicated respiratory acidosis. No changes in cardiac output were observed; however, there was a reduction in pulmonary arterial and central venous pressures and stroke volume. Fetal heart rate was significantly decreased. General inhalation anesthesia in late term pregnancy in mares in a recumbent position implies in significant hemodynamic and metabolic changes. Up to 90 minutes those changes does not seem to affect negatively the maternal-fetus prognosis.
Copyright: © 2024 Brito et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Publication Date: 2024-11-22 PubMed ID: 39576817PubMed Central: PMC11584139DOI: 10.1371/journal.pone.0313563Google Scholar: Lookup
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- Journal Article
Summary
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This research investigates the effects of anesthetic procedures on late-term pregnant mares, focusing on the resultant maternal and fetal hemodynamic changes. The study ultimately concluded that despite significant changes, the procedure didn’t negatively affect the mare or fetus over a 90-minute period.
Study Participants and Procedure
- The study involved nine adult mares approaching the last month of their gestation period. These mares underwent a general inhalation anesthesia procedure and were placed in a dorsal recumbent position for a period of 90 minutes.
- The researchers assessed several parameters at set intervals throughout the anesthetic process. These included the mares’ trans-anesthetic vital parameters, arterial hemogasometry (a method of measuring gas levels in blood), cardiac output, pulmonary arterial pressure, central venous pressure, and the fetal heart rates.
Observed Hemodynamic Changes
- During different phases of the anesthetic procedure, the mares experienced changes to various hemodynamic factors. Specifically, there was an increase in heart rate, mean arterial pressure, and diastolic pressure and a decrease in body temperature.
- Respiratory acidosis (a condition characterized by excess acid in the body due to a buildup of carbon dioxide in the blood) was observed as per the arterial hemogasometry readings.
- No noticeable changes were seen in cardiac output. However, a decrease was noted in pulmonary arterial and central venous pressures and stroke volume.
- There was a noticeable decrease in the fetal heart rate during the procedure, indicating a significant change in fetal hemodynamics.
Conclusion of the Study
- The results indicate that anesthesia in recumbent late-term mares resulted in significant hemodynamic and metabolic changes in both the mares and their fetuses.
- However, despite these changes, neither the mares nor their fetuses appeared to show any negative impacts after the 90-minute procedure. As a result, the researchers concluded that such anesthetic procedures do not adversely affect prognosis for the mare and fetus within this timeframe.
Cite This Article
APA
Brito PHS, Ferreira MA, Rusch E, Arantes JA, Carregaro AB, Valadão CAA, Ghantous GF, Dória RGS.
(2024).
Anesthesia for non-obstetric surgery during late term pregnancy in mares.
PLoS One, 19(11), e0313563.
https://doi.org/10.1371/journal.pone.0313563 Publication
Researcher Affiliations
- Department of Veterinary Medicine, Faculty of Animal Science and Food Engineering, University of São Paulo (USP), Pirassununga, São Paulo, Brazil.
- Department of Veterinary Medicine, Faculty of Animal Science and Food Engineering, University of São Paulo (USP), Pirassununga, São Paulo, Brazil.
- Department of Veterinary Medicine, Faculty of Animal Science and Food Engineering, University of São Paulo (USP), Pirassununga, São Paulo, Brazil.
- Department of Veterinary Medicine, Faculty of Animal Science and Food Engineering, University of São Paulo (USP), Pirassununga, São Paulo, Brazil.
- Department of Veterinary Medicine, Faculty of Animal Science and Food Engineering, University of São Paulo (USP), Pirassununga, São Paulo, Brazil.
- Department of Veterinary Medicine and Surgery, Faculty of Agricultural and Veterinary Sciences, UNESP-São Paulo State University, Jaboticabal, São Paulo, Brazil.
- Department of Basic Sciences, Faculty of Animal Science and Food Engineering, University of São Paulo (USP), Pirassununga, São Paulo, Brazil.
- Department of Veterinary Medicine, Faculty of Animal Science and Food Engineering, University of São Paulo (USP), Pirassununga, São Paulo, Brazil.
MeSH Terms
- Animals
- Female
- Pregnancy
- Horses
- Heart Rate, Fetal / physiology
- Hemodynamics
- Cardiac Output
- Anesthesia, General / veterinary
- Heart Rate
- Anesthesia, Inhalation / veterinary
- Blood Pressure
Conflict of Interest Statement
The authors have declared that no competing interests exist.
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