Veterinary Anaesthesia Research Articles

Impacts of xylazine on fentanyl demand, body weight, and acute withdrawal in rats: A comparison to lofexidine

The opioid use landscape has recently shifted to include xylazine, a veterinary anesthetic, as an adulterant in the fentanyl supply. The health impacts of xylazine as an emerging fentanyl adulterant has raised alarm regarding xylazine as a public health threat, warranting research on the impacts of xylazine on fentanyl's behavioral effects. No prior studies have evaluated the effects of xylazine on fentanyl consumption at various unit doses, fentanyl demand, or withdrawal as compared to the Food and Drug Administration-approved opioid withdrawal medication, lofexidine (Lucemyra®). This is important because lofexidine and xylazine are both adrenergic α2a (A2aR) agonists, however, lofexidine is not a noted fentanyl adulterant. Here we evaluated xylazine and lofexidine combined with self-administered fentanyl doses in male and female rats and evaluated fentanyl demand, body weight, and acute withdrawal. Consumption of fentanyl alone increased at various unit doses compared to saline. Xylazine but not lofexidine shifted fentanyl consumption downward at a number of unit doses, however, both lofexidine and xylazine suppressed fentanyl demand intensity as compared to a fentanyl alone control group. Further, both fentanyl + lofexidine and fentanyl + xylazine reduced behavioral signs of fentanyl withdrawal immediately following SA, but signs increased by 12 h only in the xylazine co-exposed group. Weight loss occurred throughout fentanyl SA and withdrawal regardless of group, although the xylazine group lost significantly more weight during the first 24 h of withdrawal than the other two groups. Severity of weight loss during the first 24 h of withdrawal was also correlated with severity of somatic signs of fentanyl withdrawal. Together, these results suggest that body weight loss may be an important indicator of withdrawal severity during acute withdrawal from the xylazine/fentanyl combination, warranting further translational evaluation.

Attitudes to acute pain and the use of pain assessment scales among Spanish small animal veterinarians.

This study aimed to characterize the level of concern among Spanish veterinarians regarding acute pain in companion animals. Additionally, it sought to determine whether this concern correlates with the utilization of optimal assessment tools. A survey was conducted to explore Spanish veterinarians' attitudes toward pain and its assessment. The survey was distributed through two most prominent small animal veterinary associations, the Spanish association for veterinary anesthesia and analgesia, as well as key industry players committed to proactive pain management. Descriptive analysis of the collected data was performed using Excel and SPSS. A total of 292 veterinarians participated in the study. A high level of concern regarding pain in dogs and cats was determined where 44% of surveyed veterinarians assessed pain in all patients. Despite an awareness of validated pain scales, only 28% used them. The preferred scales were the Glasgow CMPS for dogs (94%) and the Feline Grimace Scale for cats (93%). Among respondents who do not use these validated tools, there was a considerable interest in incorporating these scales into practice (85%) and considered lack of training was the most relevant issue (32%). Other challenges to scale utilization were identified, including constraints related to time, staffing, and the need to establish a habit. Spanish small animal veterinarians demonstrated a strong awareness to pain in their patients and employed various methods for pain assessment. However, a limited use of validated tools was identified and likely attributed to challenges such as a lack of established routine, time constraints, insufficient personnel, and, notably, a knowledge gap among veterinarians who do not employ pain assessment scales. The most commonly used scales were the Glasgow CMPS for dogs and the FGS for cats. Overall, these results suggest a window of opportunity for the implementation of training programs in small animal pain assessment at a national level.

Anestesia en un paciente pediátrico: Reporte de caso

Veterinary anesthesiology has been advanced in order to provide safer techniques to patients, individualizing protocols according to the needs of each animal. Just like humans, animals are classified according to age group. Pediatric patients are those between 6 and 12 weeks of age. When undergoing surgical procedures, it is crucial to remember that the development and maturation of organs does not follow the same pattern that occurs in adult animals. The present work aims to describe the anesthesia administered to a pediatric patient undergoing gastrostomy surgery. Methadone was used as pre-anesthetic medication at a dose of 0.15 mg/kg, and anesthetic induction was done via administration of propofol 2 mg/kg and fentanyl 1 mcg/kg, both intravenously. For anesthetic maintenance, we chose to use isoflurane in a universal vaporizer, with 100% oxygen supply. During the procedure, physiological parameters were kept stable within reference values, and intraoperative analgesic rescue was not necessary. The anesthetic planning for this patient provided rapid induction and recovery, without major inconvenience.

Complications of orotracheal intubation in the horse

SummaryDifficulty to extubate any patient is not a problem commonly thought of during general anaesthesia. This case report describes some of the factors that lead to this predicament and the successful surgical removal of the endotracheal tube via a tracheostomy. This case report also highlights some of the deficiencies in the clinical practice of veterinary anaesthesia. Further research is required for the selection size criteria of endotracheal tubes in all species and the monitoring of cuff pressures during general anaesthesia.

Anaesthetic mortality in dogs: A worldwide analysis and risk assessment.

Ensuring patient safety during small animal anaesthesia is crucial. This study aimed to assess anaesthetic-related deaths in dogs globally, identify risks and protective factors and inform clinical practice. This prospective cohort multicentric study involved 55,022 dogs from 405 veterinary centres across various countries. Data on anaesthesia-related deaths from premedication to 48 hours post-extubation were collected. Logistic regression was used to analyse patient demographics, American Society of Anesthesiologists (ASA) classification, procedure type and anaesthetic drugs used. Anaesthetic-related mortality was 0.69%. Most deaths occurred postoperatively (81%). Age, obesity and a higher ASA classification score were associated with increased mortality. Urgent procedures, non-urgent but unscheduled anaesthesias and short procedures also had higher mortality. Some sedatives, systemic analgesics, hypnotics and the use of locoregional anaesthesia were linked to a decrease in mortality. The limitations of the study include thenon-randomised sample, potential selection bias, lack of response rate quantification, variable data quality control, subjectivity in classifying causes of death and limited analysis of variables. Careful patient evaluation, drug selection and monitoring can be associated with reduced mortality. These findings can be used to develop guidelines and strategies to improve patient safety and outcomes. Further research is needed to refine protocols, enhance data quality systems and explore additional risk mitigation measures.

Student interest in veterinary anesthesiology

Student interest in veterinary anesthesiology

Survey on the use of total intravenous anaesthesia in small animals by veterinary anaesthesiologists

Survey on the use of total intravenous anaesthesia in small animals by veterinary anaesthesiologists

Accuracy of drawing up liquid medications by veterinary anaesthetists and nurses

ObjectiveTo evaluate the accuracy with which veterinary anaesthetists and nurses of different experience draw up small volumes of liquid. Study designProspective blinded randomized study. MethodsA group of seven European College of Veterinary Anaesthesia and Analgesia (ECVAA) diplomates, six ECVAA residents and six anaesthesia nurses participated in the study. For each participant, five target volumes between 0.01 and 1.0 mL were randomly allocated. They were drawn up 20 times in random order using a 1 mL syringe attached to a 23 gauge needle. A total of 1900 measurements were analysed. An investigator filled the syringe and needle dead space with water for injection before each experiment. The change in mass of the syringe once filled to the target volume was used to calculate the actual volume of liquid drawn up. ResultsLarge errors were made with measurements < 0.04 mL, so they were excluded from the statistical analysis. There was a significant effect of the target volume (p < 0.001) and of the order (p < 0.01). For each mL increase in the target volume, the absolute error decreased by 4% and from the first to the hundredth withdrawal each participant’s absolute error decreased by 1%. The target volume was underestimated in 52.3% of measurements, 42% were overestimated and 5.7% were on target. None of the between-subject predictor variables approached significance. Conclusions and clinical relevanceAccuracy of veterinary anaesthetists and nurses in drawing up medications decreases as the target volume becomes smaller. Small veterinary patients receive small volumes of anaesthetic drugs with higher risks of overdosing compared with larger dogs. Years of experience and staff grade are not associated with greater accuracy. Large percentage errors may be seen with target volumes less than 0.04 mL. Dilutions are recommended for volumes > 0.19 mL in 1 mL syringe.

Interactive Virtual Reality with Educational Feedback Loops to Train and Assess Veterinary Students on the Use of Anesthetic Machine

The study objective was to assess acceptability, feasibility, likeability, and applicability of interactive virtual reality with feedback loops (VR) to teach and assess veterinary anesthesia machine operation. Data from 60 students were analyzed. Students learned and trained how to use the anesthesia machine components, connections and performed safety checks (such as the pressure check) using real and VR machines. Competency was assessed with oral/practical and VR exams. A questionnaire survey gathered student affective skill perception towards VR for education. Students perceived VR for veterinary education as positive, useful, likeable, and helpful to learn the anesthesia machine. VR appeared to increase cognitive load, inducing lower VR exam scores of 100 (92.4–97.9) when compared to oral/practical exams of 100 (98–99.8) with p = .018. Training times with either real or VR anesthesia machines were similar ( p = .71). A positive correlation was found between VR training times and VR exam scores (Spearman's correlation coefficient 0.5; p &lt; .0001). No correlations were identified between oral/practical exam scores and training times. Seventy two percent of the students ( n = 43) had never used VR before. Prior VR experience was not necessary to train using VR. Computer glitches and cybersickness are important drawbacks to consider when using VR for education. The study demonstrated that interactive, immersive VR received favorable reactions from students. The VR incorporated educational feedback loops can be utilized as a simulation trainer for veterinary education. However, inherent limitations should be considered.

Inter-observer reliability of three feline pain scales used in clinical practice.

The present study aimed to evaluate the inter-observer reliability of three feline pain scales commonly used in clinical practice. Twenty cats undergoing elective neutering surgery were assessed both pre- and postoperatively by three independent assessors (a board-certified anaesthetist, a veterinary anaesthesia nurse and a final-year veterinary student) using three different pain scales: the Glasgow Feline Composite Measure Pain Scale (CMPS - Feline), the Colorado State University Feline Acute Pain Scale (CSU - FAPS) and the Feline Grimace Scale (FGS). Reliability statistics was used to evaluate the level of agreement between assessors. Twenty-seven groups of paired observations were evaluated, of which 16 (59%) showed fair agreement, eight (30%) showed none to slight agreement and the remaining three (11%) showed moderate agreement based on Cohen's weighted kappa statistics. Based on Cronbach's alpha statistics, 12 (44%) of the 27 groups of observations showed moderate reliability, 12 (44%) showed poor reliability and the remaining three (11%) showed good reliability. No scale was superior to the others in terms of inter-rater reliability (P = 0.179); however, the pair composed of the final-year veterinary student and anaesthesia nurse showed better agreement than the two other pairs of assessors, both of which included the board-certified anaesthetist (P = 0.015). Despite the usefulness of behavioural pain scales as clinical tools, their users should bear in mind their limitations, particularly the intrinsic subjectivity and potential variability of outcome between assessors with different backgrounds and level of expertise.

Changes in external respiratory during cesarean section in dogs under various methods of general anesthesia

The aim of this study was to investigate the effect of popular non-inhaled and inhaled general anesthetics on the respiratory function of dogs during operative delivery. Experimental studies have been performed on pregnant bitches that have been subjected to caesarean section. The selection of animals was carried out according to pre-selected criteria, the age of the animals participating in the experiment was from 2 to 6 years, the average body weight was 22 ± 4.6 kg. Animals were divided into 3 groups. Dogs in the first group received intravenous anesthetic propofol at a dose of 4-6 mg/kg for induction and maintenance of general anesthesia. he dogs of the second group used an inhaled halogen-containing anesthetic isoflurane 0.5–2.0 vol% for the administration and maintenance of anesthesia. For the induction and maintenance of general anesthesia in animals of the third group, a more modern inhalation anesthetic sevoflurane 1.0–2.0 vol% was used. Each group included 20 animals. Analyzing the results obtained on the study of the functions of external respiration of dogs during caesarean section under general anesthesia, it can be argued that the most significant changes in the studied parameters occurred at the initial stages of anesthesia with propofol, which are associated with an increase in the concentration of this anesthetic in the blood and a more pronounced depression of the respiratory center compared to with inhalation anesthetics.

Constructions and advances of animal models of Pseudomonas aeruginosa infection

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogenic bacterium with complex pathogenesis and drug resistance mechanisms. It has high morbidity and mortality and can cause acute and chronic infections in immunocompromised individuals, with lung infections, wound infections, and bloodstream infections being the most common. The animal infection model of P. aeruginosa is of great value for in-depth research on the pathogenicity, drug resistance, and therapeutic measures of P. aeruginosa by simulating the pathways of human bacterial infections. This article firstly summarizes the selection, anesthesia, and disposal of experimental animals in the construction of animal models of P. aeruginosa infection, and then reviews the methods of construction, model evaluation, and applications of animal models of P. aeruginosa pulmonary infection, wound infection, and bloodstream infection, in order to provide a reference for scientific research related to P. aeruginosa infectious diseases.

Capnography for the veterinary nurse

According to reports, small animal anaesthesia appears to be increasing in safety. However, greater patient care during the peri-anaesthetic period would further reduce fatalities. While there is no direct evidence to prove that the use of capnography can reduce the risk of mortality, it has been shown to prevent morbidities and has allowed for the early detection of complications before significant physiological side effects are seen. Capnography is becoming more commonplace in veterinary practice; however, it is reported that not all registered veterinary nurses feel comfortable with its use. This article provides detailed information on capnography so that registered veterinary nurses will be more knowledgeable and confident in using this method to detect and correct any issues that arise.

The effects of ketamine on viability, primary DNA damage, and oxidative stress parameters in HepG2 and SH-SY5Y cells.

Ketamine is a dissociative anaesthetic used to induce general anaesthesia in humans and laboratory animals. Due to its hallucinogenic and dissociative effects, it is also used as a recreational drug. Anaesthetic agents can cause toxic effects at the cellular level and affect cell survival, induce DNA damage, and cause oxidant/antioxidant imbalance. The aim of this study was to explore these possible adverse effects of ketamine on hepatocellular HepG2 and neuroblastoma SH-SY5Y cells after 24-hour exposure to a concentration range covering concentrations used in analgesia, drug abuse, and anaesthesia (0.39, 1.56, and 6.25 µmol/L, respectively). At these concentrations ketamine had relatively low toxic outcomes, as it lowered HepG2 and SH-SY5Y cell viability up to 30 %, and low, potentially repairable DNA damage. Interestingly, the levels of reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH) remained unchanged in both cell lines. On the other hand, oxidative stress markers [superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT)] pointed to ketamine-induced oxidant/antioxidant imbalance.

Highlights of recent clinically relevant papers

Equine Veterinary EducationVolume 35, Issue 7 p. 338-339 RESEARCH HIGHLIGHTS Highlights of recent clinically relevant papers Sue Wright, Corresponding Author Sue Wright [email protected] orcid.org/0000-0002-5513-8571 EVE Editorial Office Email: [email protected]Search for more papers by this author Sue Wright, Corresponding Author Sue Wright [email protected] orcid.org/0000-0002-5513-8571 EVE Editorial Office Email: [email protected]Search for more papers by this author First published: 01 June 2023 https://doi.org/10.1111/eve.13809Read the full textAboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. References Cameron-Whytock, H.A., Parkin, T.D.H., Hobbs, S.J., Brigden, C.V. & Bennet, E.D. (2023) Towards a safer sport: risk factors for cross-country horse falls at British Eventing competition. Equine Veterinary Journal, Epub ahead of print. Available from: https://beva.onlinelibrary.wiley.com/doi/10.1111/evj.13934 Fisher, K., Dodam, J., Bailey, J., Thombs, L., Hodgson, D. & Bukoski, A. (2023) Arterial blood gas tensions during recovery in horses anesthetized with apneustic anesthesia ventilation compared with conventional mechanical ventilation. Journal of Veterinary Anaesthesia Analgesia, Epub ahead of print. Available from: https://doi.org/10.1016/j.vaa.2023.01.004 Goldkuhl, J.E.C., Zablotski, Y., Sill, V., Jahn, W., Lorenz, I., Brunk, J. et al. (2023) Evaluation of cartilage injury in horses with osteochondral fragments in the metacarpo−/metatarsophalangeal joint: a study on 823 arthroscopies. Equine Veterinary Journal, Epub ahead of print. Available from: https://beva.onlinelibrary.wiley.com/doi/10.1111/evj.13937 Goni, J.I., Hendrix, K. & Kritchevsky, J. (2023) Recovery of salmonella bacterial isolates from pooled fecal samples from horses. Journal of Veterinary Internal Medicine., 37(1), 323– 327. Available from: https://doi.org/10.1111/jvim.16586 Terschuur, J.A., Coomer, R.P.C., Handel, I., Pressanto, M.C. & McKane, S.A. (2023) Benefits of cyanoacrylate mesh closure following exploratory laparotomy in horses. Veterinary Record, Epub ahead of print. Available from: https://doi.org/10.1002/vetr.2732 Volume35, Issue7July 2023Pages 338-339 ReferencesRelatedInformation

Inductively coupled, transmit-receive coils for proton MRI and X-nucleus MRI/MRS in small animals

We report several inductively coupled RF coil designs that are very easy to construct, produce high signal-to-noise ratio (SNR) and high spatial resolution while accommodating life support, anesthesia and monitoring in small animals. Inductively coupled surface coils were designed for hyperpolarized 13 C MR spectroscopic imaging (MRSI) of mouse brain, with emphases on the simplicity of the circuit design, ease of use, whole-brain coverage, and high SNR. The simplest form was a resonant loop designed to crown the mouse head for a snug fit to achieve full coverage of the brain with high sensitivity when inductively coupled to a broadband pick-up coil. Here, we demonstrated the coil's performance in hyperpolarized 13 C MRSI of a normal mouse and a glioblastoma mouse model at 4.7 T. High SNR exceeding 70:1 was obtained in the brain with good spatial resolution (1.53 mm x 1.53 mm). Similar inductively coupled loop for other X-nuclei can be made very easily in a few minutes and achieve high performance, as demonstrated in 31 P spectroscopy. Similar design concept was expanded to splitable, inductively coupled volume coils for high-resolution proton MRI of marmoset at 3T and 9.4T, to easily accommodate head restraint, vital-sign monitoring, and anesthesia delivery.

Urethane provides an unparalleled anaesthetic model for natural sleep: Commentary on Mondino et al., 2022.

Urethane provides an unparalleled anaesthetic model for natural sleep: Commentary on Mondino et al., 2022.

Risk of burnout and depression: A survey of veterinary anaesthesia specialists in-training during COVID-19

ObjectiveTo investigate risk, risk factors and effects on adherence to adequate clinical standards, of burnout and depression in veterinary anaesthesia residents. Study designClosed online cross-sectional survey study. Study populationA sample of 89 residents registered to the European and/or the American Colleges of Veterinary An (ae)sthesia and Analgesia out of a total of 185. MethodsA link to access an online questionnaire, which included the Maslach Burnout Inventory-Human Services Survey (MBI-HSS), the Harvard National Depression Screening Day Scale (HANDS) and 28 questions developed to assess adherence to adequate clinical standards, was sent by email to 185 residents. The three components of the MBI-HSS namely emotional exhaustion (EE), depersonalization and reduced personal accomplishment were analysed separately. Analysis of proportions and two-step regression statistical modelling were used for data analysis, and p values < 0.05 were considered statistically significant. ResultsThe response rate was 48%. Based on HANDS and MBI-HSS scores, 49% of the residents were at high risk of both depression and burnout. These residents expressed greater concern of delivering inadequate animal care (p < 0.001), of decreased quality of supervision during COVID-19 (p = 0.038) and of negative impact of the pandemic on their training programme (p = 0.002) than residents at low-to-moderate risk. Working in a clinical environment for ≥ 60 hours/week was a risk factor for both depression (p = 0.016) and EE (p = 0.022), while female sex was a risk factor for EE only (p = 0.018). Conclusions and clinical relevanceA large proportion of residents is at high risk of depression and burnout, a scenario likely worsened by the pandemic. The findings of this study suggest that reducing the clinical workload and increasing the level of support and supervision may help to improve residents’ mental health.

Waste not want not: piloting a clinical waste audit at a United States university veterinary teaching hospital.

Biomedical waste is a well-recognized environmental problem, yet less is known about the waste generated in the delivery of veterinary care compared to human medicine. The objective of this project was to develop and pilot a waste audit protocol for veterinary medicine that could inform waste management at a US university veterinary teaching hospital and the broader veterinary community. We conducted a multi-day review of the Colorado State University Veterinary Teaching Hospital's small animal surgery and anesthesia units to measure the types and amounts of waste generated during routine surgeries. Metrics included total weight, number of bags, and individual counts for specific items of concern and items with sustainable alternatives. We calculated frequencies and percentages of waste by waste audit material category and noted any erroneous materials sorted. Despite waste being a prioritized sustainability issue in veterinary medicine, this work highlighted opportunities for better education on managing and optimizing existing resources through behavior modification. This article explores ways the 5Rs (Rethink, Reduce, Reuse, Recycle, Research) could be better operationalized in veterinary hospitals.

Cross-sectional survey of sleep, fatigue and mental health in veterinary anaesthesia personnel

ObjectiveTo evaluate the sleep quality, prevalence of fatigue and depressive symptoms in veterinary anaesthesia personnel. Study designAnonymous online voluntary survey. MethodsSleep quality, fatigue, depressive symptoms and self-perceived burnout were scored using the Pittsburgh Sleep Quality Index (PSQI), Fatigue Severity Scale (FSS), Patient Health Questionnaire-9 (PHQ-9) and single-item burnout measure, respectively. Demographic data and questions about work-related fatigue, out-of-hours duty, transport and rest periods were included. PSQI, FSS and PHQ-9 scores were compared using Spearman rank correlation tests. ResultsResponses from 393 participants were obtained from an estimated population of 1374 including diplomates of the American and European Colleges of Veterinary An(a)esthesia and Analgesia (43.9%), residency-trained veterinarians (15.6%), residents-in-training (13.8%) and veterinary technicians and nurses (12.0%), from 32 countries. Most were employed in clinical university teaching hospitals (54.2%) or clinical private practice (41.5%).PSQI scores > 5 were reported by 71.2% of respondents, with 52.4% reporting insufficient sleep to meet their job demands. Many showed high or borderline fatigue (56.4%), and 74.7% reported mistakes due to work-related fatigue. Major depressive symptoms (PHQ-9 score ≥ 10) were found in 42.7%, with 19.2% reporting they had thought about suicide or self-harm in the previous 2 weeks. Over half (54.8%) met the criteria for burnout and more veterinary nurses and technicians suffered from burnout than other roles, with 79.6% of this group affected (p < 0.001).Scores for PSQI and FSS [r (388) = 0.40, p < 0.001]; PSQI and PHQ-9 [r (389) = 0.23, p < 0.001]; and FSS and PHQ-9 [r (387) = 0.24, p < 0.001] were all positively correlated. Conclusions and clinical relevanceThis survey demonstrates a high prevalence of poor sleep, fatigue, depressive symptoms and burnout in veterinary anaesthesia personnel, and more should be done to improve the health of those in the profession.