Partial intravenous anaesthesia in the horse: a review of intravenous agents used to supplement equine inhalation anaesthesia. Part 2: opioids and alpha-2 adrenoceptor agonists.

This research article reviews the use of different intravenous agents, specifically opioids and alpha-2 adrenoceptor agonists, as supplements to inhalation anesthesia in horses. The aim of this supplementation is to reduce the volume of inhaled anesthetic, improve the quality of recovery, and provide multimodal pain relief. The research also notes the need for further studies to assess the impact of these techniques on heart and lung health, and points out potential drawbacks.

Methods and Search Terms

• The research methodology used for this review includes comprehensive literature searches on Pubmed and Web of Science.
• Search terms include: horse, inhalant anaesthesia, balanced anaesthesia, partial intravenous anaesthesia, opioids, morphine, pethidine, butorphanol, methadone, fentanyl, alfentanil, remifentanil, sufentanil, xylazine, romifidine, detomidine, medetomidine and dexmedetomidine.

Supplements to Inhalation Anesthesia

• The primary focus of the review is on the use of various intravenous anesthesia agents, with an emphasis on opioids and alpha-2 adrenoceptor agonists, to supplement inhalational anaesthetics in equine medicine.
• The goal of this combined approach, often referred to as balanced anaesthesia or partial intravenous anaesthesia, is to improve the quality of anaesthesia in horses by reducing the amount of inhaled anesthetics, improving recovery qualities, and offering a multimodal approach to pain control.

Necessity for Further Research

• While the combined use of intravenous and inhaled anesthetics may offer potential benefits, the authors note that comprehensive studies to evaluate whether these techniques improve the heart and lung health status are not always available.
• Moreover, the review also highlights the need to consider potential disadvantages of these techniques, suggesting a balanced, evidence-based approach when deciding on anesthetic protocols for horses.