title: Postoperative effects of anesthesia and surgery on resting energy expenditure in horses as measured by indirect calorimetry.
abstract: In this study, we aimed to define the effects of anesthesia and surgery on the resting energy expenditure of horses in experimental conditions. Six horses were used in a longitudinal study with 2 study periods: before and after anesthesia and surgery. Every horse underwent a standard 90-min ventral midline exploratory laparotomy. Oxygen uptake (VO2) and carbon dioxide output (VCO2) were measured, with the use of a closed-circuit spirometry system, on 5 consecutive days immediately before and after the surgery. In 3 consecutive 5-min periods each day, the expired air was collected in a Collins spirometer. Samples of the expired gas were drawn from the spirometer through a drying column into O2 and CO2 analyzers. Resting energy expenditure was calculated as [(VO2 STPD*3.94) + (VCO2 STPD*1.11)]*1.44. This study showed that anesthesia and ventral midline exploratory laparotomy in experimental conditions increase the postoperative caloric demand in horses by an average of 1.0 Mcal/d, which represents approximately a 10% increase (P = 0.03). Additional studies in critically ill horses after surgery are needed to determine their caloric needs and to optimize their nutritional management.
authors.affiliation: Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, Ontario. acruz@ovc.uoguelph.ca
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Cruz
authors.forename: Nathalie
authors.initials: N
authors.lastname: Coté
authors.forename: Wayne N
authors.initials: WN
authors.lastname: McDonell
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Geor
authors.forename: Brian A
authors.initials: BA
authors.lastname: Wilson
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Monteith
authors.forename: Ronald
authors.initials: R
authors.lastname: Li
mesh_terms: D000758:Anesthesia / Q000662:veterinary*; D000818:Animals; D001481:Basal Metabolism / Q000502:physiology*; D002153:Calorimetry, Indirect / Q000379:methods / Q000662:veterinary*; D002245:Carbon Dioxide / Q000032:analysis; D004734:Energy Metabolism / Q000502:physiology*; D006736:Horses / Q000378:metabolism / Q000502:physiology / Q000601:surgery; D007813:Laparotomy / Q000379:methods / Q000662:veterinary; D008137:Longitudinal Studies; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods / Q000662:veterinary*; D010101:Oxygen Consumption / Q000502:physiology; D011184:Postoperative Period; D011659:Pulmonary Gas Exchange / Q000502:physiology; D013147:Spirometry / Q000379:methods / Q000662:veterinary; D013997:Time Factors
chemical_list: D002245:Carbon Dioxide