1
|
Horsley KT, Olby NJ, Mitchell MA, Aulakh KS, Gines JA. Effect of Sedation on the Neurological Examination of the Patellar and Withdrawal Reflexes in Healthy Dogs. Front Vet Sci 2021; 8:664150. [PMID: 34041291 PMCID: PMC8143191 DOI: 10.3389/fvets.2021.664150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 03/06/2021] [Indexed: 11/15/2022] Open
Abstract
Introduction: Pain, temperament, fear, and anxiety can prevent safe and accurate evaluation of common neurologic reflexes in dogs. When sedation is used it is unknown how the neurological examination, and specifically patellar and withdrawal reflexes are affected, and, if present, how long any effect might last. The purpose of this study is to investigate the effect of sedation on the evaluation of select common limb spinal reflexes in healthy dogs. Material and Methods: Fourteen healthy dogs with normal neurologic exams were included. After placing joint landmarks, patellar reflex and pelvic and thoracic limb withdrawal reflexes were tested. Joint angles were measured, obtaining reflex angle endpoints, change in angle, and change in time to reflex completion. These measurements were recorded at different time points: prior to sedation (awake timepoint), 15 and 30 min following administration of standardized sedation protocol of dexmedetomidine and butorphanol, and 15 and 30 min following administration of a standardized reversal agent, atipamazole. Results: For patellar reflex, the stifle end angle increased from 91.5 to 108.55 degrees (p < 0.0001) 15 min following sedation, and remained increased at 104.5 degrees (p < 0.0001) 30 min following sedation. Stifle change in angle increased from 9.6 to 24.4 degrees (p < 0.0001) 15 min following sedation, and remained increased at 20.85 degrees (p < 0.0001) and 11 degrees (p = 0.012) at 30 min sedation and 15 min reversal. Tarsal joint in pelvic withdrawal and elbow in thoracic withdrawal reflexes did not differ in at any timepoint of sedation or reversal when compared with the awake timepoint, for end angle or change in angle. The increases in end angle and change in angle for patellar reflex generated a change in time for patellar reflex from 0.12 s (awake) to 0.129 s (15 min sedation) which was statistically significant (p = 0.041). Change in time did not differ for pelvic withdrawal or thoracic withdrawal. Discussion/Conclusions: Reflexes were elicited in all dogs under sedation. Sedation does not affect the evaluation of the withdrawal reflex on any limb but improves the visualization of the patellar reflex in this group of neurologically normal dogs.
Collapse
Affiliation(s)
- Kristen T Horsley
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, United States
| | - Natasha J Olby
- College of Veterinary Medicine, North Carolina State University, Raleigh, NC, United States
| | - Mark A Mitchell
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, United States
| | - Karanvir S Aulakh
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, United States
| | - J Alberto Gines
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, United States
| |
Collapse
|
2
|
Lascelles BDX, Brown DC, Conzemius M, Gill M, Oshinsky ML, Sharkey M. Measurement of chronic pain in companion animals: Priorities for future research and development based on discussions from the Pain in Animals Workshop (PAW) 2017. Vet J 2019; 252:105370. [PMID: 31554586 DOI: 10.1016/j.tvjl.2019.105370] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 08/16/2019] [Accepted: 08/26/2019] [Indexed: 12/11/2022]
Abstract
The estimation of long-standing pain in companion animals through the measurement of different dimensions impacted by pain is a fundamental requirement if pain management, and pain therapeutic development, are to advance. Although pain management in veterinary medicine has advanced considerably in the last 20 years, there is much critical work to do in the area of measurement of chronic pain. To date, most work has centered on musculoskeletal pain, and has been focused around the measurement of limb use and the development of owner-completed questionnaires, or clinical metrology instruments (CMI). Recent areas of research have extended to developing measures of activity, sensory function (quantitative sensory testing; nociceptive withdrawal reflexes), and quality of life (QoL). Across all these areas, more data on validity are needed, and studies should be extended to other painful disease states. By necessity, assessing measurement tools requires testing in field studies, which incur considerable time and expense. Facilitating these studies could be optimized with a collaborative (industry, academia and private practice) approach, and the utility of the information produced from all field studies would be enhanced by full and transparent reporting and data sharing, including data already generated by industry in the form of studies submitted to the regulatory authorities.
Collapse
Affiliation(s)
- B D X Lascelles
- Translational Research in Pain, Comparative Pain Research and Education Centre, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA; Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA; Thurston Arthritis Center, UNC School of Medicine, Chapel Hill, NC 27517, USA; Center for Translational Pain Research, Department of Anesthesiology, Duke University, Durham, NC 27710, USA.
| | - D C Brown
- Translational and Comparative Medicine Research, Elanco Animal Health, Greenfield, IN 46140, USA
| | - M Conzemius
- Clinical Investigation Center, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA
| | - M Gill
- National Institute of Neurological Disorders and Stroke/National Institutes of Health, Bethesda, MD 20894,USA
| | - M L Oshinsky
- National Institute of Neurological Disorders and Stroke/National Institutes of Health, Bethesda, MD 20894,USA
| | - M Sharkey
- Center for Veterinary Medicine Food and Drug Administration, Rockville, MD 20855, USA
| |
Collapse
|
3
|
Lascelles BDX, Brown DC, Conzemius MG, Gill M, Oshinsky ML, Sharkey M. Measurement of chronic pain in companion animals: Discussions from the Pain in Animals Workshop (PAW) 2017. Vet J 2019; 250:71-78. [PMID: 31383423 DOI: 10.1016/j.tvjl.2019.07.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 07/01/2019] [Accepted: 07/02/2019] [Indexed: 12/31/2022]
Abstract
In the face of increasing recognition and interest in treating chronic pain in companion animals, we struggle with a lack of therapeutic options. A significant barrier to the development of new therapeutics, or the critical evaluation of current therapies, is our inability to accurately measure chronic pain and its impact on companion animals. Over the last 20 years, much progress has been made in developing methods to measure chronic pain via subjective and objective methods - particularly in owner assessment tools and measurements of limb use and activity. Most work has been focused on chronic joint pain conditions, but there has been relatively little work in other areas of chronic pain, such as neuropathic and cancer pain. Although progress has been made, there is a considerable interest in improving our assessment of chronic pain, as evidenced by the multiple disciplines across industry, academia, and clinical practice from the veterinary and human medical fields that participated in the Pain in Animals Workshop held at the National Institutes of Health in 2017. This review is one product of that meeting and summarizes the current state of knowledge surrounding the measurement of chronic pain (musculoskeletal, cancer, neuropathic), and its impact, in cats and dogs.
Collapse
Affiliation(s)
- B D X Lascelles
- Translational Research in Pain Program, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA; Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA; Thurston Arthritis Center, UNC School of Medicine, Chapel Hill, NC, USA; Center for Translational Pain Research, Department of Anesthesiology, Duke University, Durham, NC, USA.
| | - D C Brown
- Translational and Comparative Medicine Research, Elanco Animal Health, Greenfield, IN, USA
| | - M G Conzemius
- Clinical Investigation Center, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - M Gill
- National Institute of Neurological Disorders and Stroke/National Institutes of Health, Bethesda, MD, USA
| | - M L Oshinsky
- National Institute of Neurological Disorders and Stroke/National Institutes of Health, Bethesda, MD, USA
| | - M Sharkey
- Center for Veterinary Medicine Food and Drug Administration, Rockville, MD, USA
| |
Collapse
|
4
|
Hunt JR, Goff M, Jenkins H, Harris J, Knowles TG, Lascelles BDX, Mendl M, Whay HR, Murrell JC. Clinical measurements performed during alfaxalone total intravenous anaesthesia for radiography and neurophysiological investigations in dogs. Vet Anaesth Analg 2019; 46:483-487. [PMID: 31178411 DOI: 10.1016/j.vaa.2018.11.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 10/03/2018] [Accepted: 11/30/2018] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To describe clinically relevant, physiological measurements collected during a 3 hour duration of alfaxalone total intravenous anaesthesia. STUDY DESIGN Case series. ANIMALS A total of 112 client-owned middle-aged or older dogs. METHODS Dogs were premedicated with intramuscular acepromazine (0.03 mg kg-1). Anaesthesia was induced and subsequently maintained for up to 3 hours with alfaxalone administered intravenously. Dogs breathed 100% oxygen via an endotracheal tube. Heart rate, respiratory rate and blood pressure were evaluated 30 minutes after administration of acepromazine and used as baseline values for comparisons of intra-anaesthetic data. Blood glucose was measured 1 week prior to anaesthesia and every hour during alfaxalone anaesthesia. Quality and duration of recovery were recorded. Mean data for physiological variables were compared over three time points-before induction of anaesthesia, for the first hour of anaesthesia and from 60 minutes to discontinuation of anaesthesia. RESULTS Mean induction dose of alfaxalone was 1.4 mg kg-1 [95% confidence interval (CI) 1.3-1.5). Post induction apnoea for >60 seconds occurred in 13 (11.6%) dogs. Mean alfaxalone infusion rate during the first 60 minutes of anaesthesia was 0.099 mg kg-1 minute-1; mean infusion rate was 0.092 mg kg-1 minute-1 from 60 minutes until discontinuation of anaesthesia. Heart rate was well maintained; hypotension (mean arterial blood pressure < 60 mmHg) was encountered in 23 (21%) dogs. Blood glucose levels did not alter during anaesthesia. Median time between discontinuation of alfaxalone infusion and extubation was 17 (7-35 minutes), time to assuming sternal recumbency was 75 (58-110 minutes), and time to standing was 109 (88-140 minutes). CONCLUSIONS AND CLINICAL RELEVANCE Alfaxalone infusion provided effective anaesthesia in this population. In a minority of cases, respiratory and haemodynamic support of the patient was required.
Collapse
Affiliation(s)
- James R Hunt
- Bristol Veterinary School, University of Bristol, Langford, North Somerset, UK
| | - Megan Goff
- Bristol Veterinary School, University of Bristol, Langford, North Somerset, UK
| | - Helen Jenkins
- Bristol Veterinary School, University of Bristol, Langford, North Somerset, UK
| | - John Harris
- Arthritis Research UK Pain Centre and Division of Animal Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, UK
| | - Toby G Knowles
- Bristol Veterinary School, University of Bristol, Langford, North Somerset, UK
| | - B Duncan X Lascelles
- Comparative Pain Research and Education Centre, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA; Center for Pain Research and Innovation, UNC School of Dentistry, Chapel Hill, NC, USA
| | - Mike Mendl
- Bristol Veterinary School, University of Bristol, Langford, North Somerset, UK
| | - Helen R Whay
- Bristol Veterinary School, University of Bristol, Langford, North Somerset, UK
| | - Joanna C Murrell
- Bristol Veterinary School, University of Bristol, Langford, North Somerset, UK.
| |
Collapse
|
5
|
Electrophysiological characterisation of central sensitisation in canine spontaneous osteoarthritis. Pain 2019; 159:2318-2330. [PMID: 29994993 DOI: 10.1097/j.pain.0000000000001336] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
In man, central sensitisation (CS) contributes to the pain of osteoarthritis (OA). Dogs with spontaneous OA may also exhibit CS. Electrophysiological reflex measurements are more objective than behavioural assessments and can be used to evaluate CS in preclinical and clinical studies. It was hypothesised that dogs suffering from OA would exhibit electrophysiological characteristics indicative of CS, associated with reduced diffuse noxious inhibitory controls (DNICs). One hundred and seventeen client-owned dogs were recruited to the study. Hind limb nociceptive withdrawal reflex thresholds, stimulus response, and temporal summation characteristics were recorded, during alfaxalone anaesthesia, from 46 OA dogs, 29 OA dogs receiving nonsteroidal anti-inflammatory drugs (OANSAIDs), and 27 breed- and weight-matched control dogs. Efficacy of DNIC was evaluated in 12 control and 11 of the OA dogs, by application of a mechanical conditioning stimulus to the contralateral forelimb. Nociceptive withdrawal reflex thresholds were higher in OA compared with control dogs (P = 0.02). Stimulus response characteristics demonstrated an augmented response in OANSAID dogs compared with OA (P < 0.001) and control (P < 0.001) dogs. Temporal summation demonstrated exaggerated C-fibre-mediated responses in both OA (P < 0.001) and OANSAID (P = 0.005) groups, compared with control animals. Conditioning stimulus application resulted in inhibition of test reflex responses in both OA and control animals (P < 0.001); control animals demonstrated greater inhibition compared with OA (P = 0.0499). These data provide evidence of neurophysiological changes consistent with CS in dogs with spontaneous OA and demonstrate that canine OA is associated with reduced DNIC.
Collapse
|
6
|
Gainfully employing descending controls in acute and chronic pain management. Vet J 2018; 237:16-25. [DOI: 10.1016/j.tvjl.2018.05.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 12/30/2022]
|
7
|
Pypendop BH, Ranasinghe MG, Pasloske K. Comparison of two intravenous anesthetic infusion regimens for alfaxalone in cats. Vet Anaesth Analg 2018; 45:459-466. [PMID: 29853416 DOI: 10.1016/j.vaa.2018.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 03/26/2018] [Accepted: 03/27/2018] [Indexed: 12/30/2022]
Abstract
OBJECTIVE To compare the performance of an alfaxalone constant rate intravenous (IV) infusion versus a 3-step IV infusion, both following a loading dose, for the maintenance of a target plasma alfaxalone concentration of 7.6 mg L-1 (effective plasma alfaxalone concentration for immobility in 99% of the population) in cats. STUDY DESIGN Prospective randomized crossover study. ANIMALS A group of six healthy, adult male neutered cats. METHODS Catheters were placed in a jugular vein for blood sampling and in a medial saphenous vein for drug administration. An IV bolus of alfaxalone (2 mg kg-1) was administered, followed by either 0.2 mg kg-1 minute-1 for 240 minutes (single infusion; SI) or 0.4 mg kg-1 minute-1 for 10 minutes, then 0.3 mg kg-1 minute-1 for 30 minutes, and then 0.2 mg kg-1 minute-1 for 200 minutes (3-step infusion; 3-step). Plasma alfaxalone concentration was measured at six time points during the infusions. Measures of performance were calculated for each infusion regimen and compared using the paired Wilcoxon signed-rank test. RESULTS Median (range) absolute performance error, divergence, median prediction error and wobble were 15 (8-19)%, -8 (-12 to -6)% hour-1, -12 (-19 to -7)% and 10 (8-19)%, respectively, in the SI treatment, and 6 (2-16)%, 0 (-13 to 2)% hour-1, 1 (-16 to 4)% and 4 (3-6)% respectively, in the 3-step treatment and were significantly smaller in the 3-step treatment than in the SI treatment. CONCLUSION AND CLINICAL RELEVANCE After IV administration of a bolus dose, a 3-step infusion regimen can better maintain stable plasma alfaxalone concentrations close to the target concentration than a single constant rate infusion.
Collapse
Affiliation(s)
- Bruno H Pypendop
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA.
| | | | | |
Collapse
|
8
|
Lascelles BDX, Brown DC, Maixner W, Mogil JS. Spontaneous painful disease in companion animals can facilitate the development of chronic pain therapies for humans. Osteoarthritis Cartilage 2018; 26:175-183. [PMID: 29180098 DOI: 10.1016/j.joca.2017.11.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 10/17/2017] [Accepted: 11/13/2017] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To outline the role that spontaneous osteoarthritis (OA) in companion animals can play in translational research and therapeutic pharmacological development. OUTLINE Narrative review summarizing the opportunities and limitations of naturally occurring, spontaneous OA as models of human OA pain, with a focus on companion animal pets. The background leading to considering inserting spontaneous disease models in the translational paradigm is provided. The utility of this model is discussed in terms of outcome measures that have been validated as being related to pain, and in terms of the potential for target discovery is outlined. The limitations to using companion animal pets as models of human disease are discussed. CONCLUSIONS Although many steps along the translational drug development pathway have been identified as needing improvement, spontaneous painful OA in companion animals offers translational potential. Such 'models' may better reflect the complex genetic, environmental, temporal and physiological influences present in humans and current data suggests the predictive validity of the models are good. The opportunity for target discovery exists but is, as yet, unproven.
Collapse
Affiliation(s)
- B D X Lascelles
- Comparative Pain Research Program, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA; Center for Pain Research and Innovation, UNC School of Dentistry, Chapel Hill, NC, USA; Center for Translational Pain Research, Department of Anesthesiology, Duke University, Durham, NC, USA.
| | - D C Brown
- Translational Comparative Medicine Research, Elanco Animal Health, Greenfield, IN, USA
| | - W Maixner
- Center for Translational Pain Research, Department of Anesthesiology, Duke University, Durham, NC, USA
| | - J S Mogil
- Department of Psychology, Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada; Department of Anesthesia, Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| |
Collapse
|
9
|
Adrian D, Papich M, Baynes R, Murrell J, Lascelles BDX. Chronic maladaptive pain in cats: A review of current and future drug treatment options. Vet J 2017; 230:52-61. [PMID: 28887012 DOI: 10.1016/j.tvjl.2017.08.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 08/10/2017] [Accepted: 08/17/2017] [Indexed: 11/28/2022]
Abstract
Despite our increasing understanding of the pathophysiology underlying chronic or maladaptive pain, there is a significant gap in our ability to diagnose and treat the condition in domestic cats. Newer techniques being used to identify abnormalities in pain processing in the cat include validated owner questionnaires, measurement of movement and activity, and measurement of sensory thresholds and somatomotor responses. While some data are available evaluating possible therapeutics for the treatment of chronic pain in the cat, most data are limited to normal cats. This review details our current understanding of chronic or maladaptive pain, techniques for the detection and measurement of the condition and the associated central nervous changes, as well as an overview of the data evaluating potential therapeutics in cats.
Collapse
Affiliation(s)
- Derek Adrian
- Comparative Pain Research and Education Centre, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA
| | - Mark Papich
- Molecular and Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA
| | - Ron Baynes
- Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA
| | - Jo Murrell
- School of Veterinary Sciences, University of Bristol, Bristol, UK
| | - B Duncan X Lascelles
- Comparative Pain Research and Education Centre, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA; Center for Pain Research and Innovation, UNC School of Dentistry, Chapel Hill, NC, USA; Center for Translational Pain Research, Department of Anesthesiology, Duke University, Durham, NC, USA.
| |
Collapse
|