Introduction

• Maintenance of general anesthesia   Anesthesia: general - overview   in the horse using a combination of alpha-2 adrenoceptor agonists, ketamine   Ketamine hydrochloride   and GGE (guaifenesin)    Guaifenesin   mixed in dextrose   Glucose  and given intravenously.

Uses

• Minor surgical procedures that can't be undertaken using standing sedation   Anesthesia: standing chemical restraint  and local analgesia   Anesthesia: local - overview   might be performed in the field using this total intravenous general anesthesia techniques (TIVA)   Anesthesia: intravenous (IV)  .
• The same techniques can also be used in simple surgical facilities where volatile anesthetic maintenance agents aren't available.

Indications

• Minor surgical procedures which are likely to require <1 h total anesthetic time.
• Small to medium sized, well mannered, healthy horses.
• Suitable procedures include lumpectomies, castration   Testis: castration - overview   and wound management   Wound: management - overview  .

Contraindications

• Major surgical procedures likely to require >1 h anesthesia.
• Surgical procedures in large, flighty horses.
• Such procedures include laparotomies    Abdomen: laparotomy  for colic   Abdomen: pain - adult  or caesarean section   Uterus: caesarean section  .

Advantages

• Can be carried out away from normal practice facilities.
• There is evidence that this technique has fewer cardiovascular depressant effects than volatile anesthetic agents.
• Can be carried out with minimal equipment.

Disadvantages

• Prolonged recovery times when used to maintain anesthesia for >90 min.
• Surgical anesthesia is characterized by the retention of ocular and laryngeal reflexes so this technique is not ideal for eye or laryngeal/pharyngeal surgery.

Requirements

Preparation

Procedure

Aftercare

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• Austin S M (2013) Assessment of the equine neonate in ambulatory practice. Equine Vet Educ 25 (11), 585-589 VetMedResource.
• Stanway G (2000) Anaesthesia for minor surgical procedures in the horse. In Pract 23 (1), 22-26 VetMedResource.
• Taylor P M, Kirby J J, Shrimpton D J & Johnson C B (1998) Cardiovascular effects of surgical castration during anaesthesia maintained with halothane or infusion of detomidine, ketamine and guaiphenesin in ponies. Equine Vet J 30 (4), 304-309 PubMed.
• Van Dijk P (1996) Intravenous anaesthesia in horses by guaiphenesin-ketamine-detomidine infusion: some effects. Vet Q 16 Suppl 2, S122-125 PubMed.
• Luna S P L, Taylor P M & Wheeler M J (1996) Cardiovascular, endocrine and metabolic changes in ponies undergoing intravenous or inhalation anaesthesia. J Vet Pharm Therap 19 (4), 251-258 PubMed.
• Johnston G M, Taylor P M, Holmes M A & Wood J L N (1995) Confidential enquiry of perioperative equine fatalities (CEPEF-1): Preliminary results. Equine Vet J 27, 193-200 PubMed.
• Taylor P M & Luna S P L (1995) Total intravenous anaesthesia in ponies using detomidine, ketamine and guaiphenesin: pharmacokinetics, cardiopulmonary and endocrine effects. Res Vet Sci 59 (1), 17-23 PubMed.
• Greene S A, Thurmon M S, Tranquilli M S & Benson M S (1986) Cardiopulmonary effects of continuous intravenous infusion of guaifenesin, ketamine and xylazine in ponies. Am J Vet Res 47 (11), 2364-2367 PubMed.