Peter Buss1, Michele Miller2, Andrea Fuller3, Anna Haw4, Eliza Stout5, Francisco Olea-Popelka5, Leith Meyer3. 1. Veterinary Wildlife Services, South African National Parks, Kruger National Park, Skukuza, South Africa; Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa; Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, South Africa. Electronic address: peter.buss@sanparks.org. 2. Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical Tuberculosis Research, Medical Research Council Centre for TB Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa. 3. Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa; Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, South Africa. 4. Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa. 5. Colorado State University, College of Veterinary Medicine and Biomedical Science, Department of Clinical Sciences, Fort Collins, CO, USA.
Abstract
OBJECTIVE: To investigate the effects of postinduction butorphanol administration in etorphine-immobilized white rhinoceros on respiration and blood gases. STUDY DESIGN: Randomized crossover study. ANIMALS: A group of six sub-adult male white rhinoceros. METHODS:Etorphine, or etorphine followed by butorphanol 12 minutes after recumbency, was administered intramuscularly [2.5 mg etorphine, 25 mg butorphanol (1000-1250 kg), or 3.0 mg etorphine, 30 mg butorphanol (1250-1500 kg)]. Sampling started at 10 minutes after initial recumbency, and was repeated at 5 minute intervals for 25 minutes. Arterial blood gases, limb muscle tremors, expired minute ventilation and respiratory frequency were measured at each sampling point. Calculated values included alveolar-arterial oxygen gradient [ [Formula: see text] ], expected respiratory minute volume (V˙e), tidal volume (Vt), oxygen consumption ( [Formula: see text] ) and carbon dioxide production ( [Formula: see text] ). RESULTS:Etorphine administration resulted in an initial median (range) hypoxaemia [arterial partial pressure of oxygen 25.0 (23.0-28.0) mmHg], hypercapnia [arterial partial pressure of carbon dioxide 76.2 (67.2-81.2) mmHg], increased [Formula: see text] [41.7 (36.6-45.1) mmHg, [Formula: see text] [11.1 (10.0-12.0) L minute-1] and muscle tremors. Butorphanol administration was followed by rapid, although moderate, improvements in arterial partial pressure of oxygen [48.5 (42.0-51.0) mmHg] and arterial partial pressure of carbon dioxide [62.8 (57.9-75.2) mmHg]. In rhinoceros administered butorphanol, [Formula: see text] [4.4 (3.6-5.1) L minute-1] and [Formula: see text] [4.2 (3.8-4.4) L minute-1] were lower than in those not administered butorphanol. Increased arterial oxygen tension was associated with lower oxygen consumption (p=0.002) which was positively associated with lower muscle tremor scores (p<0.0001). CONCLUSIONS AND CLINICAL RELEVANCE: Hypoxaemia and hypercapnia in etorphine-immobilized rhinoceros resulted from an increased [ [Formula: see text] ] and increased [Formula: see text] and [Formula: see text] associated with muscle tremors. Rather than being associated with changes in V˙e, it appears that improved blood gases following butorphanol administration were a consequence of decreased [Formula: see text] associated with reduced muscle tremoring.
RCT Entities:
OBJECTIVE: To investigate the effects of postinduction butorphanol administration in etorphine-immobilized white rhinoceros on respiration and blood gases. STUDY DESIGN: Randomized crossover study. ANIMALS: A group of six sub-adult male white rhinoceros. METHODS:Etorphine, or etorphine followed by butorphanol 12 minutes after recumbency, was administered intramuscularly [2.5 mg etorphine, 25 mg butorphanol (1000-1250 kg), or 3.0 mg etorphine, 30 mg butorphanol (1250-1500 kg)]. Sampling started at 10 minutes after initial recumbency, and was repeated at 5 minute intervals for 25 minutes. Arterial blood gases, limb muscle tremors, expired minute ventilation and respiratory frequency were measured at each sampling point. Calculated values included alveolar-arterial oxygen gradient [ [Formula: see text] ], expected respiratory minute volume (V˙e), tidal volume (Vt), oxygen consumption ( [Formula: see text] ) and carbon dioxide production ( [Formula: see text] ). RESULTS:Etorphine administration resulted in an initial median (range) hypoxaemia [arterial partial pressure of oxygen 25.0 (23.0-28.0) mmHg], hypercapnia [arterial partial pressure of carbon dioxide 76.2 (67.2-81.2) mmHg], increased [Formula: see text] [41.7 (36.6-45.1) mmHg, [Formula: see text] [11.1 (10.0-12.0) L minute-1] and muscle tremors. Butorphanol administration was followed by rapid, although moderate, improvements in arterial partial pressure of oxygen [48.5 (42.0-51.0) mmHg] and arterial partial pressure of carbon dioxide [62.8 (57.9-75.2) mmHg]. In rhinoceros administered butorphanol, [Formula: see text] [4.4 (3.6-5.1) L minute-1] and [Formula: see text] [4.2 (3.8-4.4) L minute-1] were lower than in those not administered butorphanol. Increased arterial oxygen tension was associated with lower oxygen consumption (p=0.002) which was positively associated with lower muscle tremor scores (p<0.0001). CONCLUSIONS AND CLINICAL RELEVANCE: Hypoxaemia and hypercapnia in etorphine-immobilized rhinoceros resulted from an increased [ [Formula: see text] ] and increased [Formula: see text] and [Formula: see text] associated with muscle tremors. Rather than being associated with changes in V˙e, it appears that improved blood gases following butorphanol administration were a consequence of decreased [Formula: see text] associated with reduced muscle tremoring.
Authors: Julia Bohner; Johanna Painer; Denyse Bakker; Anna Jean Haw; Hanna Rauch; Eva Maria Greunz; Beate Egner; Frank Goeritz Journal: Front Vet Sci Date: 2022-08-10
Authors: Leith C R Meyer; Andrea Fuller; Markus Hofmeyr; Peter Buss; Michele Miller; Anna Haw Journal: J S Afr Vet Assoc Date: 2018-10-18 Impact factor: 1.474
Authors: Donald Neiffer; Peter Buss; Jennie Hewlett; Guy Hausler; Leana Rossouw; Tebogo Manamela; Brittany Grenus; Emily Thulson; Francisco Olea-Popelka; Michele Miller Journal: Front Vet Sci Date: 2019-11-14
Authors: Friederike Pohlin; Emma H Hooijberg; Peter Buss; Nikolaus Huber; Francois P Viljoen; Dee Blackhurst; Leith C R Meyer Journal: Front Vet Sci Date: 2020-10-20
Authors: Shweta Trivedi; Christina M Burnham; Christian M Capobianco; Christiaan Boshoff; Yaxin Zheng; Jordan Wood Pettiglio; Kimberly Ange-van Heugten; Heidi D Bissell; Larry J Minter Journal: Vet Med Int Date: 2021-07-19