Maternal and Foetal Cardiovascular Effects of the Anaesthetic Alfaxalone in 2‐Hydroxypropyl‐β‐cyclodextrin in the Pregnant Ewe

Abstract

The objective of this study was to determine the pharmacodynamics effects of the anaesthetic alfaxalone in 2-hydroxypropyl-β-cyclodextrin in pregnant sheep after the intravenous injection of a 2 mg/kg weight dose. Six pregnant Ripollesa sheep, weighing 47.1 ± 4.4 kg, were used. Twenty-four hours after instrumentation, sheep were anaesthetized with intravenous alfaxalone in cyclodextrin. Time to standing from anaesthesia was 30.0 ± 10.81 min. Foetal heart rate increased significantly during the first 5 min after alfaxalone administration. Significant differences were observed in maternal diastolic arterial blood pressure between minute 10 and minutes 90, 120, 150, 180, 210, and 240. Significant differences were observed for foetal systolic arterial blood pressure between 5 and 30 min after alfaxalone administration. Significant differences in foetal pH were detected during the entire study period, whereas maternal pH returned to baseline values by 60 min after alfaxalone administration. The present study indicated that alfaxalone in 2-hydroxypropyl-β-cyclodextrin administered as an intravenous bolus at 2 mg/kg body weight produced minimal adverse effects and an uneventful recovery from anaesthesia in pregnant sheep and their foetus.

Maternal and fetal arterial blood gas data during general anaesthesia for caesarean delivery of preterm twin lambs

“…15 These results are consistent with other studies but the fetus can survive because of specific adaptations enabling high oxygen delivery to fetal tissues and organs. 15,16 Factors contributing to the development of ventilation and perfusion mismatching include the pregnancy status of the sheep, the supine position and the Trendelenburg position. 6 Although the pulmonary complications of anaesthesia and recumbency in sheep contribute to the risk of anaesthetic-related complications they can be managed and did not appear to cause any detrimental effects in either the ewe or the fetuses in this study.…”

“…15 These results are consistent with other studies but the fetus can survive because of specific adaptations enabling high oxygen delivery to fetal tissues and organs. 15,16…”

Anesthetic and cardiorespiratory effects of single-bolus intravenous alfaxalone with or without intramuscular xylazine-premedication in calves

“…Alpacas, goats and sheep are among the ruminants in which the anesthetic effect of alfaxalone-HPCD alone has been investigated [ 2 , 3 , 6 , 8 ]. del Álamo et al [ 6 ] reported that the dose sufficient to allow endotracheal intubation was 2.1 ± 0.1 mg/kg, and the time from induction to standing was 34.1 ± 3.2 min in 5 alpacas (weight: 96.7 ± 19.9 kg) anesthetized with alfaxalone-HPCD alone.…”

Alfaxalone for total intravenous anaesthesia in bitches undergoing elective caesarean section and its effects on puppies: a randomized clinical trial

“…A single bolus of alfaxalone produced longer recoveries in pregnant than in non‐pregnant ewes (Andaluz et al. ). As a consequence, it has been recommended to reduce drug dosage by 25% in pregnant animals.…”

“…Pregnancy may produce alterations in uptake, distribution and disposition of anaesthetic agents (Raffe & Carpenter 2007). A single bolus of alfaxalone produced longer recoveries in pregnant than in non-pregnant ewes (Andaluz et al 2013). As a consequence, it has been recommended to reduce drug dosage by 25% in pregnant animals.…”