Comparison of cardiovascular function and quality of recovery in isoflurane‐anaesthetised horses administered a constant rate infusion of lidocaine or lidocaine and medetomidine during elective surgery

Abstract

The combination of an intraoperative constant rate infusion of lidocaine and medetomidine did not adversely affect cardiovascular function in isoflurane-anaesthetised horses and improved the quality of recovery when compared to an intraoperative infusion of lidocaine alone.

High doses of lidocaine as a constant rate infusion in propofol/fentanyl anaesthetized sheep: cardiorespiratory effects

“…However, the time for the animals to remain standing was longer compared with lidocaine alone, whereas this authors assign this improved effect to the sedative effects of medetomidine. When fentanyl is used in sheep at a dose of 10 μg/ kg i.v., sedation continues for 60 minutes after its administration (WATERMAN; LIVINGSTON; AMIN, 1990), although one case of prolonged recovery has also been reported (kRONEN et al, 2005). Analyzing the results of these authors, it is possible that the residual sedative and analgesic effects of fentanyl (HUGHES; NOLAN, 1999) may have influenced the scores observed in the GPFL group because no signs of excitation were observed.…”

“…An intraoperative CRI of lidocaine (50 μg/kg/minute) induces ataxia and a poor quality of recovery in horses; thus, it is necessary to discontinue the infusion 30 minutes before the end of surgery (VALVERDE et al, 2005). In horses, Valverde et al (2010) reported that the combination of a CRI of lidocaine and medetomidine induces better recovery quality scores. However, the time for the animals to remain standing was longer compared with lidocaine alone, whereas this authors assign this improved effect to the sedative effects of medetomidine.…”

“…The effects of opioids in ruminants are controversial . Waterman, Livingston and Amin (1990) showed that doses of 5 μg/kg of fentanyl administered as a bolus in sheep did not show any antinociceptive effect against mechanical stimulation. However, when the dose was increased to 10 and 20 μg/kg it proved to be effective.…”

“…Due to these characteristics, it is commonly used as a continuous infusion in combination with the anesthetic protocol (LAMONT; MATTHEWS, 2007). The efficiency of fentanyl on nociceptive thermal and mechanical stimulation and the respiratory depression when given as a bolus in doses ranging from 5 to 20 µg/kg have been evaluated (WATERMAN; LIVINGSTON; AMIN, 1990). The higher doses were required to achieve analgesia; however, at a 10 µg/kg dose, there was a decrease in PaO 2 and an increase in PaCO 2 at 5 and 10 minutes after administration, with the values returning to baseline within 15 minutes.…”

Continuous intravenous lidocaine infusion during isoflurane anaesthesia in horses undergoing surgical procedures

“…Driessen (2005) reviewed early the potential of IV lidocaine CRI for equine PIVA and presented some personal experience with a reduced infusion rate (1.8 mg kg -1 h -1 ) compared to previous publications (Doherty und Frazier 1998, Dzikiti et al 2003) that used 3 to 6 mg kg -1 h -1 . Further investigations confirmed the ability of systemic administration of lidocaine to decrease dose-dependently anaesthetic requirements during general anaesthesia in horses , Valverde et al 2010) without intra-anaesthetic physiological or metabolic adverse effects (Valverde et al 2010, but with the risk at the recommended dosage (3 mg kg -1 h -1 ) to develop high plasma levels under general anaesthesia (Feary et al 2005) and poor quality of the recovery phase , Valverde et al 2010). To our knowledge at the moment this study was performed, there were only two trials performed to compare the administration of lidocaine to a control group in a clinical setting (Dzikiti et al 2003, but using high dose of lidocaine and with different recovery methods.…”