Anna Binetti1, Martina Mosing2, Muriel Sacks2, Luc Duchateau3, Frank Gasthuys3, Stijn Schauvliege3. 1. Department of Large Animals Surgery and Anaesthesia, Ghent University, Gent, Belgium. Electronic address: anna.binetti@Ugent.be. 2. Section of Anaesthesiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. 3. Department of Large Animals Surgery and Anaesthesia, Ghent University, Gent, Belgium.
Abstract
OBJECTIVE: To describe the cardiorespiratory effects of a change in table position in anaesthetized horses. STUDY DESIGN: Prospective, crossover, randomized, experimental study. ANIMALS: Six adult horses (mean body weight 621 ± 59 kg, aged 13 ± 4 years). METHODS: The horses were anaesthetized twice in dorsal recumbency. They were either placed in the Trendelenburg position (head down; HD) followed by reverse Trendelenburg position (head up; HU) or in reverse order. Every position was maintained for 90 minutes. The order of positions was randomly assigned at initial anaesthesia. Extensive cardiorespiratory monitoring was performed. Statistical analysis consisted of a mixed model with horses as random effect and time, position, section of anaesthesia and interaction between those as fixed effects (p < 0.05). RESULTS: When HU was applied during the first section of anaesthesia, PaO2, (p = 0.012), oxygen saturation (SaO2, p < 0.01) and oxygen content (CaO2, p < 0.01) were significantly higher, while venous admixture (Q˙s/Q˙t, p < 0.01), mean arterial (p = 0.039), right atrial (p < 0.01) and mean pulmonary arterial pressure (p < 0.01) were lower than in HD. After changing from HU to HD, PaO2 and SaO2 remained higher and Q˙s/Q˙t lower compared to the inverse order. Independent of the order, in the HD position Q˙s/Q˙t (p = 0.019) increased while PaO2 (p < 0.01), SaO2 (p = 0.011), CaO2 (p < 0.01), venous PO2 (Pv¯O2; p = 0.019), venous saturation (p = 0.004) and venous oxygen content (p = 0.010) decreased over time. No significant differences were found for cardiac output, oxygen delivery, oxygen consumption and dobutamine requirement between the two positions. CONCLUSIONS AND CLINICAL RELEVANCE: Gas exchange is better preserved in HU compared to HD, especially if applied from the start of the anaesthesia.
OBJECTIVE: To describe the cardiorespiratory effects of a change in table position in anaesthetized horses. STUDY DESIGN: Prospective, crossover, randomized, experimental study. ANIMALS: Six adult horses (mean body weight 621 ± 59 kg, aged 13 ± 4 years). METHODS: The horses were anaesthetized twice in dorsal recumbency. They were either placed in the Trendelenburg position (head down; HD) followed by reverse Trendelenburg position (head up; HU) or in reverse order. Every position was maintained for 90 minutes. The order of positions was randomly assigned at initial anaesthesia. Extensive cardiorespiratory monitoring was performed. Statistical analysis consisted of a mixed model with horses as random effect and time, position, section of anaesthesia and interaction between those as fixed effects (p < 0.05). RESULTS: When HU was applied during the first section of anaesthesia, PaO2, (p = 0.012), oxygen saturation (SaO2, p < 0.01) and oxygen content (CaO2, p < 0.01) were significantly higher, while venous admixture (Q˙s/Q˙t, p < 0.01), mean arterial (p = 0.039), right atrial (p < 0.01) and mean pulmonary arterial pressure (p < 0.01) were lower than in HD. After changing from HU to HD, PaO2 and SaO2 remained higher and Q˙s/Q˙t lower compared to the inverse order. Independent of the order, in the HD position Q˙s/Q˙t (p = 0.019) increased while PaO2 (p < 0.01), SaO2 (p = 0.011), CaO2 (p < 0.01), venous PO2 (Pv¯O2; p = 0.019), venous saturation (p = 0.004) and venous oxygen content (p = 0.010) decreased over time. No significant differences were found for cardiac output, oxygen delivery, oxygen consumption and dobutamine requirement between the two positions. CONCLUSIONS AND CLINICAL RELEVANCE: Gas exchange is better preserved in HU compared to HD, especially if applied from the start of the anaesthesia.
Authors: Cori D Youngblood; David S Hodgson; Warren L Beard; Yuqi Song; Punit Prakash; Lindsay V Heflin Journal: Can J Vet Res Date: 2020-07 Impact factor: 1.310
Authors: Laura Tucker; Daniel Almeida; Erin Wendt-Hornickle; Caroline F Baldo; Sandra Allweiler; Alonso G P Guedes Journal: Animals (Basel) Date: 2022-02-01 Impact factor: 2.752