AAHA anesthesia guidelines for dogs and cats

The effect of intravenous hydromorphone alone or in combination with midazolam or dexmedetomidine on intraocular pressure in dogs

OBJECTIVE

To evaluate the effect of intravenous (IV) hydromorphone alone or in combination with midazolam or dexmedetomidine on intraocular pressure (IOP) in dogs.

STUDY DESIGN

Prospective, randomized, blinded, crossover study.

ANIMALS

A group of seven healthy, ophthalmologically normal, adult Beagle dogs.

METHODS

A total of four IV drug combinations were evaluated: hydromorphone 0.1 mg kg-1 (H); hydromorphone 0.1 mg kg-1 and dexmedetomidine 0.001 mg kg-1 (HD); hydromorphone 0.1 mg kg-1 and midazolam 0.2 mg kg-1 (HM2); and hydromorphone 0.1 mg kg-1 and midazolam 0.4 mg kg-1 (HM4). Treatment order was randomized, with a 2 week washout period between treatments. IOP and sedation scores were obtained before (T0) and 3, 30, 60, 240 and 480 minutes after drug injection. To account for repeated measurements for each dog across treatments and time points, mixed models were used to compare IOP at T0 by eye and to describe changes from T0 in IOP (averaged across eyes) and sedation scores.

RESULTS

In treatment H, IOP increased significantly from baseline levels [predicted mean increase of 5.5 mmHg [95% confidence interval (CI): 3.7-7.3] at T3 (p < 0.001) and 2.7 mmHg (95% CI: 0.9-4.5) at T30 (p = 0.005)]. In treatment HD, mean IOP increased from baseline by 2.3 mmHg (95% CI: 0.5-4.1) at T30 (p = 0.014). In treatment HM2, mean IOP increased by 2.5 mmHg (95% CI: 0.2-4.9) at T30 (p = 0.035). In treatment HM4, IOP did not change significantly from baseline at any time point. Sedation scores over time did not differ significantly between treatments.

CONCLUSIONS AND CLINICAL RELEVANCE

Injection of IV hydromorphone alone (0.1 mg kg-1) caused a transient increase in IOP and might not be appropriate if an acute increase in IOP is undesirable. Addition of dexmedetomidine or midazolam to hydromorphone, at the doses studied, appears to attenuate this increase in IOP.

Anaesthetic practices and attitudes to patient safety in a sample of Australian veterinary practices

OBJECTIVE

To survey anaesthetic practices and attitudes towards veterinary patient safety in Australia.

STUDY DESIGN

This was a cross-sectional sample population from Australian veterinary practices, including first opinion small animal, mixed animal and referral small animal practices. The survey included practices' anaesthetic management, monitoring equipment and topics regarding patient safety.

RESULTS

Responses were obtained from 310/1700 (18%) veterinary practices, with 208 respondents from small animal practices (67%), 71 mixed animal practices (23%) and 31 referral small animal centres (10%). Overall, 61% of respondents reported always having a dedicated staff member monitoring the anaesthetic, who was most commonly a certified veterinary nurse (89%). In 22% of the practices, some of the staff monitoring an anaesthetic did not have any qualification. Completion of anaesthetic plans for each animal prior to an anaesthetic was reported by 24.5% of respondents and labelling of syringes was completed in 80% of practices. Pulse oximetry (98%) and temperature (88%) were the most common clinical variables monitored. The use of capnography (46%) or an electrocardiogram (48%) was also reported by the respondents. Emergency drugs, airway and ventilation equipment are available in 96%, 88% and 59% of practices, respectively. A defibrillator was available in 11% of practices with only 54% respondents being confident in using it. Of the respondents 60% were aware of anaesthesia safety interventions and clinical guidelines regarding patient safety during anaesthesia.

CONCLUSIONS AND CLINICAL RELEVANCE

Despite practices showing a relative improvement over the years in the standard of anaesthesia care, most of them are still not meeting international guidelines. Areas where changes could lead to improved safety practices could include: a trained person dedicated to monitor anaesthesia, pain scoring evaluation in patients recovering from anaesthesia, an increased use of standardised handover checklists, record keeping and an increase in open discussion of adverse events by the veterinary team.

Isolation and characterization of Chlamydia felis and its pathogenesis in cats

Feline upper respiratory tract disease (URTD) is a common but complicated disease that occurs in domestic cats, worldwide. 396 cats in Guangxi Province, China were screened for URTD-associated pathogens from March 2022 to August 2023. Mycoplasma felis was found to be the most prevalent infectious agent with a positivity rate of 24.75 %, followed by feline calicivirus (FCV), Chlamydia felis, feline herpesvirus 1 (FHV-1) and feline influenza A virus (FeIAV) with rates of 15.91, 11.62, 5.56 and 1.52 %, respectively. In particular, C. felis and M. felis were found in 13 of 55 co-infected cats. Of the 46 C. felis-positive samples, one strain, named as GXNN36, was successfully isolated using chicken embryos and it was characterized both in vivo and in vitro. For the cat studies, both high- and low-dose challenged groups showed severe conjunctivitis, accompanied by transient fever and respiratory symptoms. C. felis replicated well in turbinate, trachea and lung tissues with high copy numbers and the infection subsequently spread to the livers, spleens, pancreas, kidneys, hearts and intestines. These findings will help our understanding of the role of C. felis in feline URTD and provide a valuable model to evaluate the efficacy of vaccines and therapeutic remedies in the future.

Evaluation of the analgesic effects of diclofenac as a premedication drug in dogs undergoing ovariohysterectomy

Pre-emptive analgesia consists of administering drugs such as opioids and nonsteroid anti-inflammatory drugs. This study aims to evaluate the intraoperative antinociceptive effects of diclofenac administered alone in premedication or combined with morphine along with its potential influence on recovery of dogs undergoing ovariohysterectomy. A total of 34 dogs (ASA I or II) admitted for ovariohysterectomy were randomly allocated into three groups according to the drugs given in premedication: Diclofenac (D) (n = 11), Morphine (M) (n = 13) and Diclofenac-Morphine (DM) (n = 10) groups. Induction and maintenance of anesthesia were standardized in all dogs. To assess intraoperative nociception, the heart rate (HR) and mean arterial pressure (MAP) were recorded during the surgery and at predefined time points: St (steady-state), Cut (cutaneous incision), P1 (first ovarian manipulation), P2 (second ovarian manipulation) and Cerv (cervical manipulation). The dynamic variation of HR (ΔHR) and MAP (ΔMAP) over 2 min was calculated at each time point. After extubation, early quality of recovery was assessed. Compared to St, a significant increase in HR and MAP at P1, P2 and Cerv was shown in all groups. MAP in the M group was lower at St than in the other groups. The dynamic variation of HR (ΔHR) and MAP (ΔMAP) was significantly less important at P2 and Cerv compared to P1 only in the DM group. Also, a better quality of recovery was shown in the D group compared to the M and DM groups. Diclofenac may be considered a suitable premedication drug and a part of a multimodal anesthetic approach in dogs.

Efficacy of lumbosacral and sacrococcygeal epidural ropivacaine in dogs undergoing surgery for perineal hernia

Epidural anesthesia is commonly administered as part of balanced anesthesia for perioperative analgesia. The main goal of this randomized clinical trial was to compare the efficacy of two epidural approaches in dogs undergoing surgery for a perineal hernia. A secondary aim was to compare motor blockade. Intact ASA 1 and 2 male dogs, weighing ≤25 kg with no previous surgery for perineal hernia were enrolled. After premedication with IM acepromazine 0.02 mg/kg and butorphanol 0.3 mg/kg, general anesthesia was induced with propofol and maintained with sevoflurane in oxygen. Dogs were randomly allocated to receive either a lumbosacral (LS, n = 30) or a sacrococcygeal (SC, n = 26) epidural injection with ropivacaine 1% (0.2 mL/kg) under computed tomography guidance. Successful analgesia was defined as no need of intraoperative rescue analgesia (fentanyl 3 μg/kg IV). Clinical failure was defined as the need of more than two boluses of fentanyl/h each dog received meloxicam 0.2 mg/kg IV at the end of the surgery. The Glasgow Composite Pain Scale short form (GCPS-SF), tactile sensitivity, pressure pain thresholds and motor blockade were assessed at 4, 6, 8, and 24 h after the epidural injection. Methadone (0.2 mg/kg, IV) was administered if the GCPS-SF was ≥6/24 points. Differences between groups were analyzed with the Mann-Whitney U test, Student's t-test or Fisher's Exact test, as appropriate. Success rate was assessed for non-inferiority between groups. The non-inferiority margin was set at -10%. Epidural analgesia was successful in 24 dogs in group LS and 17 dogs in group SC (p = 0.243), resulting in success rates of 80 and 65% in LS and SC groups, respectively. The non-inferiority of group SC versus group LS was confirmed. Clinical failure was recorded in two dogs in group LS and one dog in group SC. No significant differences between groups were detected in the GCPS-SF score, tactile sensitivity, pressure pain thresholds, need of post-operative methadone, or motor blockade. Both epidural techniques are valuable analgesic options for perineal hernia repair in dogs.

Effect of Hot Water Bottles on Body Temperature during Magnetic Resonance Imaging in Dogs under General Anesthesia: A Retrospective Study

Prevention of hypothermia induced by anesthesia and enhanced by low environmental temperatures is difficult in magnetic resonance imaging (MRI) examinations in dogs as forced warming devices, including magnetic materials, are not acceptable for use in the MRI room. A hot water bottle (HWB) can be carried into an MRI examination room and can contribute to the prevention or attenuation of hypothermia. Here, we retrospectively investigated the effects of HWB on body temperature during MRI examinations in dogs under general anesthesia (GA). From anesthesia records of the Veterinary Medical Teaching Hospital, Okayama University of Science, validated data of 100 dogs that underwent an MRI examination under GA were obtained and divided into the following two groups: one group received HWB, while the other did not. Decrease in rectal temperature 15 min after intubation was significantly smaller in the group using HWB than in the group without HWB. In conclusion, the use of hot water bottles might be one of the methods to attenuate hypothermia in the early period but should not be expected for complete prevention of hypothermia, and it was not recommendable necessarily for body temperature management during MRI examinations in dogs under general anesthesia.

Comparison of the sedative and analgesic effects of butorphanol with acepromazine, midazolam, or dexmedetomidine following propofol induction and isoflurane maintenance in canines

Adequate sedation and excellent depth of analgesia were recorded in all the four groups after induction to the end of surgical procedure, however, significantly higher sedation score and depth of analgesia were observed in group D and significantly lower was observed in group A in comparison to other groups. Butorphanol with acepromazine, midazolam, or dexmedetomidine provides adequate sedation and analgesia in the dogs, before induction with propofol, so it made handling of the animals proper and safe before induction. Dexmedetomidine produces most profound sedation and analgesia followed by midazolam and acepromazine along with butorphanol.

Using a combination of midazolam and butorphanol is a safe and effective reversible field sedation protocol for Weddell seal (Leptonychotes weddellii) pups

BACKGROUND

Weddell seals (Leptonychotes weddellii) are a well-studied species of phocid with an apparent sensitivity to immobilising agents. Mortality as high as 31% has been reported during field immobilisation. This study investigated the use of a benzodiazepine in combination with an opioid agonist/antagonist for sedation in Weddell seal pups as part of a physiological study.

METHODS

During the 2017 and 2019 Antarctic pupping seasons, 18 Weddell seal pups were sedated by intramuscular administration of a combination of midazolam and butorphanol or intravenous midazolam alone. Individuals were sedated at 1, 3, 5 and 7 weeks of age. Naltrexone and flumazenil were used to reverse sedation. The combination was 100% effective in providing appropriate sedation for the intended procedures.

RESULTS

Analyses were performed to investigate relationships between dose administered, age, individual reactions, adverse effects and changes in dive physiology. Transient apnoea (10-60 seconds) was the most frequently observed adverse effect. No sedation-associated morbidity or mortality occurred.

LIMITATIONS

The sample size is small and there is no pharmacokinetic information for either sedative or reversal in phocid species.

CONCLUSIONS

The combination of midazolam (0.2-0.3 mg/kg) and butorphanol (0.1-0.2 mg/kg) provided safe and effective sedation, with reversible effects, in Weddell seal pups.

Effects of vatinoxan in dogs premedicated with medetomidine and butorphanol followed by sevoflurane anaesthesia: a randomized clinical study

OBJECTIVE

To investigate effects of vatinoxan in dogs, when administered as intravenous (IV) premedication with medetomidine and butorphanol before anaesthesia for surgical castration.

STUDY DESIGN

A randomized, controlled, blinded, clinical trial.

ANIMALS

A total of 28 client-owned dogs.

METHODS

Dogs were premedicated with medetomidine (0.125 mg m^-2) and butorphanol (0.2 mg kg^-1) (group MB; n = 14), or medetomidine (0.25 mg m^-2), butorphanol (0.2 mg kg^-1) and vatinoxan (5 mg m^-2) (group MB-VATI; n = 14). Anaesthesia was induced 15 minutes later with propofol and maintained with sevoflurane in oxygen (targeting 1.3%). Before surgical incision, lidocaine (2 mg kg^-1) was injected intratesticularly. At the end of the procedure, meloxicam (0.2 mg kg^-1) was administered IV. The level of sedation, the qualities of induction, intubation and recovery, and Glasgow Composite Pain Scale short form (GCPS-SF) were assessed. Heart rate (HR), respiratory rate (f_R), mean arterial pressure (MAP), end-tidal concentration of sevoflurane (Fe'Sevo) and carbon dioxide (Pe'CO₂) were recorded. Blood samples were collected at 10 and 30 minutes after premedication for plasma medetomidine and butorphanol concentrations.

RESULTS

At the beginning of surgery, HR was 61 ± 16 and 93 ± 23 beats minute^-1 (p = 0.001), and MAP was 78 ± 7 and 56 ± 7 mmHg (p = 0.001) in MB and MB-VATI groups, respectively. No differences were detected in f_R, Pe'CO₂, Fe'Sevo, the level of sedation, the qualities of induction, intubation and recovery, or in GCPS-SF. Plasma medetomidine concentrations were higher in group MB-VATI than in MB at 10 minutes (p = 0.002) and 30 minutes (p = 0.0001). Plasma butorphanol concentrations were not different between groups.

CONCLUSIONS AND CLINICAL RELEVANCE

In group MB, HR was significantly lower than in group MB-VATI. Hypotension detected in group MB-VATI during sevoflurane anaesthesia was clinically the most significant difference between groups.

Success of placement and complications during v-gel placement and maintenance of anaesthesia

OBJECTIVES

Airway management during anaesthesia in cats is always a demanding task and is associated with several complications. The aim of this study was to evaluate the practicability and complications during feline-specific laryngeal mask placement in anaesthetised cats as an alternative to endotracheal intubation.

METHODS

In this prospective clinical study, laryngeal masks were placed in 148 anaesthetised cats. Success of placement was evaluated by capnography.

RESULTS

Placement was possible at the first attempt in 136 cats, at the second attempt in eight cats and at the third attempt in one cat. In one cat, placement was not possible. Two cats were excluded. Failure to position the laryngeal mask at the first attempt was not different between laryngeal mask sizes (P = 0.313) or positioning during placement (P = 0.406). In nine cats, the laryngeal mask dislocated during the procedure. Dislocation occurred more often in the dorsal position than in the sternal (P = 0.018) and right lateral positions (P = 0.046). Mucous obstruction of the laryngeal mask occurred in one of these cats and regurgitation in another. Material-related issues, such as disconnection of the parts of the laryngeal mask and leakage of the balloon, were observed in 2/8 laryngeal masks.

CONCLUSIONS AND RELEVANCE

The placement of a feline-specific laryngeal mask was easy to perform. In about 7% of the cases, replacement of the device was required due to mispositioning or dislocation. Full monitoring, including capnography, should be provided to uncover dislocation and airway obstruction immediately.

Case Report: Successful Reperfusion of Pulmonary Thromboembolism Using tPA in a Cat

Pulmonary thromboembolism is a potentially life threatening condition that is uncommonly recognized in cats. Thrombolytic agents have been described as a treatment for this condition in human and canine patients, particularly in cases where hemodynamic instability is persistent despite supportive care. This report describes the clinical course, echocardiographic diagnosis, and successful thrombolysis of a cat with pulmonary thromboembolism. Despite confirmed reperfusion, the cat succumbed to thromboembolic disease highlighting the dearth of knowledge about optimal treatment of this disease process in small animals, particularly in cats.

Accuracy of heart rate measurements of three smartwatch models in dogs

This study was aimed to evaluate the accuracy of heart rate (HR) measurements using three smartwatch models designed for human use when applied to dogs. A group of 15 mixed breed dogs, ages ranging from 2 to 3 years, weighing between 20 and 30 kg were used. The Garmin Fenix 5X plus (GF5Xp), Samsung Gear S3 (SGS3), and Polygold A-6 (PDA6), were randomly placed on the tibia of dogs to collect the HR recordings every 5 minutes for 1 hour. A veterinary patient monitor (VPM) was used as the reference method. A Bland-Altman plot was applied to determine the difference between smartwatches. The receiver operating characteristic curves were developed analysis for sensitivity and specificity. The HR measured by VPM ranged from 65 to 200 bpm (mean, 149.3 ± 28.1 bpm; median, 154 bpm). Among the smartwatches, the lowest (44 bpm) HR was measured by PDA6, while the highest (201 bpm) was measured by SGS3. Among the smartwatches; GF5Xp and SGS3 had slopes equal to 1 and residual standard deviation closer to 0, in agreement with VPM. At the cut-off HR (160 bpm), SGS3 had the highest sensitivity (97.4%), whereas PDA6 had the lowest sensitivity (68.0%). The specificity of GF5Xp, SGS3, and PDA6 was 97.1%, 98.0%, and 98.0%, respectively. The SGS3 and GF5Xp can be ideal tools for veterinarians to monitor the HR of dogs without requiring an additional device.

The Effect of the Preoperative Fasting Regimen on the Incidence of Gastro-Oesophageal Reflux in 90 Dogs

Simple Summary

Gastro-oesophageal reflux (GOR), a potential risk during anaesthesia, happens when the stomach contents move up into the oesophagus. The refluxed contents can damage the lining of the oesophagus or the respiratory tract. For many years it was believed that an increase in the stomach contents’ volume increases the risk of GOR. However, more recent studies have demonstrated this to be incorrect. The objective of this study was to compare the effects of three different pre-anaesthetic fasting regimens on the frequency of GOR in dogs under anaesthesia. Ninety dogs undergoing non-abdominal and non-thoracic elective surgery were included in the study and equally allocated to three groups. The results of this study suggest that the administration of a meal 3 h before anaesthesia does not have any beneficial effect in the reduction of GOR incidence in dogs compared to the administration of a meal 12 h before anaesthesia.

Abstract

This study aimed to investigate the effect of three different preoperative fasting regimens on the incidence of gastro-oesophageal reflux (GOR) in dogs under general anaesthesia. Ninety dogs undergoing non-abdominal and non-thoracic elective surgery were included in the study and equally allocated to three groups. Dogs received canned food providing half the daily resting energy requirements (RER) 3 h prior to premedication (group 3H), a quarter of the daily RER 3 h before premedication (group 3Q), and half the daily RER 12 h before premedication (group 12H). The animals were premedicated with acepromazine and pethidine, anaesthesia was induced with propofol and maintained with isoflurane vaporised in oxygen. Oesophageal pH was monitored throughout anaesthesia. Demographic and surgery-related parameters were not different among groups. The incidence of GOR was 11/30 in group 3H (36.7%), 9/30 in group 3Q (30.0%) and 5/30 in group 12H (16.7%), which was not statistically different (p = 0.262). Reduction of the amount of the preoperative meal from half to a quarter of the daily RER did not reduce the incidence of GOR but resulted in a lower oesophageal pH (p = 0.003). The results of this study suggest that the administration of a meal 3 h before anaesthesia does not have any beneficial effect in the reduction of GOR incidence in dogs compared to the administration of a meal 12 h before anaesthesia.

Use of subdermal hyaluronic acid injections and a free labial mucocutaneous graft for the repair of feline eyelid agenesis

OBJECTIVE

To describe a technique to repair feline eyelid agenesis using a hyaluronic acid (HA) subdermal filler injection to allow for acute soft tissue expansion, followed by a free labial mucocutaneous graft.

MATERIALS AND METHODS

Thirty-nine colobomatous eyelids in 24 feline patients with secondary keratitis were recruited to the study group.

RESULTS

Keratitis and trichiasis were markedly resolved in 27/39 (69.2%) eyelids after a single procedure. Post-operative HA subdermal filler injections were required to resolve 5/39 (12.8%) eyelids that had mild post-operative trichiasis, and 1/39 (2.5%) eyelids that had post-operative lateral canthal collapse. Complications occurred in 6/39 (15.4%) cases, consisting of distal graft necrosis (n = 2 eyes), suture rubbing the cornea (n = 2 eyes), moderate trichiasis (n = 1 eye) and graft adherence to the episclera (n = 1 eye).

CONCLUSION

The technique was successful in enhancing corneal protection, cosmesis and eyelid function and should be considered as a surgical option for any degree of eyelid agenesis in feline patients.

Designing and Equipping a Modern Dentistry and Oral Surgery Suite

Veterinary practices should consider designing and equipping a dedicated space to provide companion animal dental and oral surgical care. A single or multi-table dental suite design will allow organized and efficient delivery of dental care. Each workstation should be equipped with a procedural table that will allow for drainage, shadow-free procedural lighting, an anesthetic machine with monitoring, thermal support, anesthetic scavenger system, dental radiographic equipment, and an air-driven dental delivery system. Lift tables, dental-specific seating, swivel handpieces, and headlamp/surgical loupe lighting should also be considered to improve ergonomics.

Multi-Omics Approach to Elucidate Cerebrospinal Fluid Changes in Dogs with Intervertebral Disc Herniation

Herniation of the intervertebral disc (IVDH) is the most common cause of neurological and intervertebral disc degeneration-related diseases. Since the disc starts to degenerate before it can be observed by currently available diagnostic methods, there is an urgent need for novel diagnostic approaches. To identify molecular networks and pathways which may play important roles in intervertebral disc herniation, as well as to reveal the potential features which could be useful for monitoring disease progression and prognosis, multi-omics profiling, including high-resolution liquid chromatography-mass spectrometry (LC-MS)-based metabolomics and tandem mass tag (TMT)-based proteomics was performed. Cerebrospinal fluid of nine dogs with IVDH and six healthy controls were used for the analyses, and an additional five IVDH samples were used for proteomic data validation. Furthermore, multi-omics data were integrated to decipher a complex interaction between individual omics layers, leading to an improved prediction model. Together with metabolic pathways related to amino acids and lipid metabolism and coagulation cascades, our integromics prediction model identified the key features in IVDH, namely the proteins follistatin Like 1 (FSTL1), secretogranin V (SCG5), nucleobindin 1 (NUCB1), calcitonin re-ceptor-stimulating peptide 2 precursor (CRSP2) and the metabolites N-acetyl-D-glucosamine and adenine, involved in neuropathic pain, myelination, and neurotransmission and inflammatory response, respectively. Their clinical application is to be further investigated. The utilization of a novel integrative interdisciplinary approach may provide new opportunities to apply innovative diagnostic and monitoring methods as well as improve treatment strategies and personalized care for patients with degenerative spinal disorders.

Quantification of normetanephrine in canine urine using ELISA: evaluation of factors affecting results

Catecholamine release increases in dogs with pheochromocytomas and in situations of stress. Although plasma catecholamines degrade rapidly, their metabolites, normetanephrine (NME) and metanephrine (ME), are stable in acidified urine. Our aim was to verify a human urine ELISA kit for the quantification of NME and ME in canine urine and to determine the effects on metabolite stability of sampling time (morning or midday) and day (ordinary or day spent in a clinic). We analyzed 179 urine samples from 17 healthy dogs. For NME, the mean intra-assay CV was 6.0% for all samples and 4.3% for the canine control; inter-assay CVs were 3.3, 3.8, and 12% for high and low concentration human urine positive controls supplied in the ELISA kit and a positive canine control, respectively; spike-recovery was 90-101%. For ME, mean intra-assay CV was 6.5% for samples and 9.0% for the canine control; inter-assay CVs were 12.7, 7.2, and 22.5% for high and low concentration human urine positive controls supplied in the ELISA kit and a positive canine control, respectively; spike-recovery was 85-89%. Dilution recovery was unsatisfactory for both metabolites. Based on our verification results, NME was selected for remaining analyses. We found no effect on NME concentrations of acidification or room temperature storage for up to 24 h. The NME:creatinine ratio was higher after the first of 3 clinic days compared to the same morning (111.2 ± 5.5 vs. 82.9 ± 5.3; p < 0.0001), but not on the other days. NME verification results were generally superior to ME. Dilution studies were unsatisfactory for both metabolites. Given that NME was stable without acidification at room temperature, urine samples can be collected at home. The clinic environment can cause higher NME:creatinine ratios, especially in unaccustomed dogs.

Management of veterinary anaesthesia and analgesia in small animals: A survey of English-speaking practitioners in Canada

OBJECTIVE

To describe how small animal anaesthesia and analgesia is performed in English-speaking Canada, document any variation among practices especially in relation to practice type and veterinarian's experience and compare results to published guidelines.

DESIGN

Observational study, electronic survey.

SAMPLE

126 respondents.

PROCEDURE

A questionnaire was designed to assess current small animal anaesthesia and analgesia practices in English-speaking Canadian provinces, mainly in Ontario, Alberta and British Columbia. The questionnaire was available through SurveyMonkey® and included four parts: demographic information about the veterinarians surveyed, evaluation and management of anaesthetic risk, anaesthesia procedure, monitoring and safety. Year of graduation and type of practice were evaluated as potential risk factors. Exact chi-square tests were used to study the association between risk factors and the association between risk factors and survey responses. For ordinal data, the Mantel-Haenszel test was used instead.

RESULTS

Response rate over a period of 3 months was 12.4% (126 respondents out of 1 016 invitations). Current anaesthesia and analgesia management failed to meet international guidelines for a sizable number of participants, notably regarding patient evaluation and preparation, safety and monitoring. Nearly one third of the participants still consider analgesia as optional for routine surgeries. Referral centres tend to follow guidelines more accurately and are better equipped than general practices.

CONCLUSIONS AND CLINICAL RELEVANCE

A proportion of surveyed Canadian English-speaking general practitioners do not follow current small animal anaesthesia and analgesia guidelines, but practitioners working in referral centres are closer to meet these recommendations.

The impact of periodontal disease and dental cleaning procedures on serum and urine kidney biomarkers in dogs and cats

The objective of this study was to evaluate the benefits and inherent risks of dental cleaning procedures, based on serum and urine biomarkers for kidney function and tissue damage, in dogs and cats. Thirty-one asymptomatic, mostly older dogs (14 neutered male and 17 ovariohysterectomized female dogs of various breeds between 3 and 14 years old) and cats (19 neutered male and 12 ovariohysterectomized female domestic short hair cats between 2 and 16 years old) diagnosed with periodontal disease on physical exam, and recommended by their veterinarian to have dental cleaning under general anesthesia were evaluated in a prospective study. Serum and urine samples were collected from dogs and cats 1 week before, 6 hours after, and again 1 week after the dental cleaning procedure. Samples were analyzed for biomarkers of kidney function [serum creatinine (Cr), symmetric dimethylarginine (SDMA), and blood urea nitrogen (BUN), and urine for specific gravity (USG) and protein:creatinine (UPC) ratio]. A panel of biomarkers for renal tissue damage was also assessed [serum β-aminoisobutyric acid (BAIB), and urine cystatin B and clusterin]. Samples collected one week before dental cleaning procedures showed that increased age and severity of dental disease were linked to abnormal kidney function biomarker values (age: elevated SDMA and Cr concentrations and isosthenuric USG values; disease severity: elevated UPC ratios) as well as elevated urine cystatin B and clusterin concentrations. Directly after the dental cleaning procedure, an increased number of cats with elevated SDMA concentrations was observed (specifically in cats with longer duration of dental procedures). Extended duration of dental procedures (≥60 min) was linked to increased urine cystatin B and clusterin concentrations, whereas shorter duration procedures was linked to decreased urine cystatin B and clusterin. Higher SDMA concentrations persisted in cats one week after the dental cleaning procedures and were linked to elevated UPC ratios one week before cleaning procedures. In conclusion, the results of this study indicate a link between severity of dental disease, renal tissue injury, and impaired renal function. Longer duration dental procedures in cats may carry inherent risks of kidney injury and impaired renal function.

Agreement between invasive and oscillometric arterial blood pressure measurement using a high-definition oscillometric device in normotensive New Zealand White rabbits using two different anaesthetic protocols

OBJECTIVE

To use American College of Veterinary Internal Medicine (ACVIM) criteria to evaluate a high-definition oscillometric (HDO) blood pressure monitoring device versus invasive blood pressure (IBP) measurement in normotensive rabbits anaesthetized with two different anaesthetic protocols.

STUDY DESIGN

Prospective experimental study.

ANIMALS

A group of 20 healthy adult New Zealand White rabbits weighing 4.36 ± 0.37 kg (mean ± standard deviation).

MATERIALS AND METHODS

Rabbits were premedicated with butorphanol 0.5 mg kg^-1 and midazolam 0.5 mg kg^-1 subcutaneously (SC, group BMA) or ketamine 25 mg kg^-1 and medetomidine 0.4 mg kg^-1 SC (group KM). Anaesthesia was induced with alfaxalone administered intravenously (group BMA) or isoflurane by face mask (group KM) and maintained with isoflurane in oxygen. IBP was measured from the central auricular artery. The cuff for the HDO monitor was placed distal to the left elbow and distal to the left tarsus. Agreement between invasive and HDO measurements was evaluated using Bland-Altman method.

RESULTS

In group KM there was better agreement between the HDO device and IBP when the cuff was placed on the thoracic limb, with 100% and 91% of the readings for mean (MAP) and diastolic arterial pressure (DAP), respectively, within 10 mmHg of the IBP measurements. The agreement, although worse, also met the ACVIM criteria for systolic arterial pressure (SAP; 53% of the readings within 10 mmHg). In group BMA, the device met the criteria with the cuff on the thoracic limb only, and only for MAP and DAP (73% and 75% of the measurements within 10 mmHg of the IBP, respectively) but not for SAP (12%).

CONCLUSION AND CLINICAL RELEVANCE

The HDO device met most of the ACVIM criteria for noninvasive blood pressure measurement in anaesthetized rabbits, specifically when the cuff was placed distal to the elbow and the anaesthetic protocol included ketamine and medetomidine.

Intraoperative Assessment of Fluid Responsiveness in Normotensive Dogs under Isoflurane Anaesthesia

The aim of this study was to evaluate the incidence of fluid responsiveness (FR) to a fluid challenge (FC) in normotensive dogs under anaesthesia. The accuracy of pulse pressure variation (PPV), systolic pressure variation (SPV), stroke volume variation (SVV), and plethysmographic variability index (PVI) for predicting FR was also evaluated. Dogs were anaesthetised with methadone, propofol, and inhaled isoflurane in oxygen, under volume-controlled mechanical ventilation. FC was performed by the administration of 5 mL/kg of Ringer's lactate within 5 min. Cardiac index (CI; L/min/m²), PPV, (%), SVV (%), SPV (%), and PVI (%) were registered before and after FC. Data were analysed with ANOVA and ROC tests (p < 0.05). Fluid responsiveness was defined as 15% increase in CI. Eighty dogs completed the study. Fifty (62.5%) were responders and 30 (37.5%) were nonresponders. The PPV, PVI, SPV, and SVV cut-off values (AUC, p) for discriminating responders from nonresponders were PPV >13.8% (0.979, <0.001), PVI >14% (0.956, <0.001), SPV >4.1% (0.793, <0.001), and SVV >14.7% (0.729, <0.001), respectively. Up to 62.5% of normotensive dogs under inhalant anaesthesia may be fluid responders. PPV and PVI have better diagnostic accuracy to predict FR, compared to SPV and SVV.

Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine or Carprofen After Periodontal Treatment in Dogs

The early effectiveness of 5 analgesics was investigated after periodontal treatment. Dogs were assigned to 6 groups (n = 14 each). A prospective, randomized and blinded clinical study was performed. Before anesthesia was induced, butorphanol, morphine, carprofen and saline were administered. After induction, a maxillary and mandibular block was performed with lidocaine or bupivacaine. Painful periodontal therapies were performed. Two hours after the administration of analgesics and after anesthesia reversal, pain was scored using the Visual Analog Scale for pain (VAS) and the modified University of Melbourne Pain Score (UMPS). Blood glucose and cortisol levels were measured prior to analgesic administration and again 2 hours later. Rescue analgesia was provided when the VAS exceeded 50 mm or the UMPS exceeded 14 points. Rescue analgesia was required in one patient in the morphine group and one in the carprofen group. The VAS values were significantly lower in the butorphanol group compared to those of the saline group and in the bupivacaine group vs. those in the saline and lidocaine groups. Significantly lower UMPS values were obtained in the bupivacaine group compared to those in the saline, butorphanol and lidocaine groups and in the carprofen group vs. those in the saline and lidocaine groups. Significantly higher serum cortisol values were found in the lidocaine group compared to those in the saline, bupivacaine and carprofen groups. Administration of carprofen or the use of nerve blocks with bupivacaine improved analgesia after periodontal treatment more than did butorphanol, morphine or nerve blocks using lidocaine.

Comparison of Hematological and Biochemical Results Derived from Arterial and Venous Blood Samples in Post-Anesthetic Dogs

Simple Summary

In contrast to humans, general anesthesia is required for both surgical procedures and diagnostic imaging like magnetic resonance imaging (MRI) and computed tomography (CT) in small animals. Because the post-anesthetic period is a particularly high risk time for death, serial monitoring of biochemical and hematological parameters could be required. Blood samples could be collected from an indwelling arterial catheter to avoid stress caused by venipuncture, but studies using arterial blood for hematological and biochemical testing have been limited. The aim of this study is to compare hematological and biochemical results derived from venous and arterial blood samples, and to evaluate their clinical interchangeability in post-anesthetic dogs. We found statistically significant but clinically irrelevant differences in hemoglobin, glucose, creatinine, and calcium levels, and results from venous and arterial blood samples are not clinically interchangeable for gamma-glutamyl transpeptidase and potassium levels.

Abstract

Collecting blood from an indwelling arterial catheter may reduce stress from repeated venipuncture in patients requiring serial monitoring, but the use of arterial blood for hematological and biochemical testing remains understudied. Here, we compared hematological and biochemical results of arterial and venous blood and evaluated their clinical interchangeability. Blood samples from dogs who had recovered from anesthesia, collected by both arterial catheterization and venipuncture, were analyzed. To assess clinical acceptance between paired samples, the limit of agreement between the values derived from the arterial and venous blood samples was compared with the allowable total error (TEa) recommended for each parameter. We found no significant differences between the arterial and venous sample results for red/white blood cell and platelet counts and hematocrit, blood urea nitrogen, phosphate, total protein, albumin, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transpeptidase, total bilirubin, sodium, potassium, and chloride levels, whereas hemoglobin, glucose, creatinine, and calcium levels differed significantly (p < 0.05). Moreover, only gamma-glutamyl transpeptidase and potassium exceeded the recommended TEa. Hematological and biochemical results derived from venous and arterial blood samples are clinically interchangeable in post-anesthetic dogs, with the exception of gamma-glutamyl transpeptidase and potassium; thus, these values should be used with caution.

Prospective Evaluation of a Citrate-Based Biomaterial Wedge for a Modified Maquet Procedure in the Treatment of Cranial Cruciate Ligament Rupture in Dogs

OBJECTIVE

 The aim of this study was to describe short- and mid-term outcomes, complications, implant bioabsorption and owner satisfaction for a modified Maquet procedure (MMP) in which a novel bioabsorbable citrate-based implant is used as the wedge component to treat cranial cruciate ligament rupture in client-owned dogs.

STUDY DESIGN

 Prospective clinical study of dogs (n = 13) undergoing MMP (n = 15). Intraoperative complications, postoperative complications, clinical follow-up using a 5-point lameness score and radiographs at 8 weeks and 6 months postoperatively were obtained. Mid-term outcome was assessed via physical examination, radiographs, canine orthopaedic index and owner satisfaction questionnaires.

RESULTS

 No catastrophic complications occurred. Major complications occurred in 3/15 stifles. All were surgical site infections and one case required implant removal. Minor complications occurred in 9/15 stifles. Non-displaced cortical hinge fractures were the most common minor complication, and these occurred intraoperatively (4/15) or postoperatively (2/15). Three dogs achieved full function, eight dogs acceptable function and the outcome was unacceptable in two dogs. Most owners were satisfied with the procedure (11/13). Complete implant bioabsorption was not confirmed on mid-term radiographs.

CONCLUSION

 The described MMP with a citrate-based implant can produce satisfactory mid-term results. However, the long-term outcome of this procedure must be evaluated and technical modifications need to be implemented prior to larger-scale use of this implant.

Feline calicivirus strain 2280 p30 antagonizes type I interferon-mediated antiviral innate immunity through directly degrading IFNAR1 mRNA

Feline calicivirus (FCV) belongs to the Caliciviridae, which comprises small RNA viruses of both medical and veterinary importance. Once infection has occurred, FCV can persist in the cat population, but the molecular mechanism of how it escapes the innate immune response is still unknown. In this study, we found FCV strain 2280 to be relatively resistant to treatment with IFN-β. FCV 2280 infection inhibited IFN-induced activation of the ISRE (Interferon-stimulated response element) promoter and transcription of ISGs (Interferon-stimulated genes). The mechanistic analysis showed that the expression of IFNAR1, but not IFNAR2, was markedly reduced in FCV 2280-infected cells by inducing the degradation of IFNAR1 mRNA, which inhibited the phosphorylation of downstream adaptors. Further, overexpression of the FCV 2280 nonstructural protein p30, but not p30 of the attenuated strain F9, downregulated the expression of IFNAR1 mRNA. His-p30 fusion proteins were produced in Escherichia coli and purified, and an in vitro digestion assay was performed. The results showed that 2280 His-p30 could directly degrade IFNAR1 RNA but not IFNAR2 RNA. Moreover, the 5’UTR of IFNAR1 mRNA renders it directly susceptible to cleavage by 2280 p30. Next, we constructed two chimeric viruses: rFCV 2280-F9 p30 and rFCV F9-2280 p30. Compared to infection with the parental virus, rFCV 2280-F9 p30 infection displayed attenuated activities in reducing the level of IFNAR1 and inhibiting the phosphorylation of STAT1 and STAT2, whereas rFCV F9-2280 p30 displayed enhanced activities. Animal experiments showed that the virulence of rFCV 2280-F9 p30 infection was attenuated but that the virulence of rFCV F9-2280 p30 was increased compared to that of the parental viruses. Collectively, these data show that FCV 2280 p30 could directly and selectively degrade IFNAR1 mRNA, thus blocking the type I interferon-induced activation of the JAK-STAT signalling pathway, which may contribute to the pathogenesis of FCV infection.

Vaccination against FCV has been available for many years and has effectively reduced the incidence of clinical disease. However, vaccines cannot prevent infection, and vaccinated cats can still become persistently infected by FCV, suggesting that FCV has evolved several strategies for counteracting various components of the innate and adaptive immune systems. Here, we show that FCV strain 2280 is resistant to the antiviral effect of IFN. The molecular mechanism by which this occurs is that FCV 2280 infection blocks the JAK-STAT pathway through promoting the degradation of IFNAR1 mRNA by FCV p30 protein. An in vitro degradation assay demonstrated that 2280 p30, but not p30 of the vaccine strain F9, could directly and selectively decay IFNAR1 RNA. The exchange of p30 between 2280 and F9 strains using a reverse genetic system also showed that 2280 p30 is a key factor that contributes to the resistance to IFN and enhances virulence. Our findings reveal a new mechanism evolved by FCV to circumvent the host antiviral response.

Cross-sectional survey of anaesthesia and analgesia protocols used to perform routine canine and feline ovariohysterectomies

OBJECTIVE

To collect baseline descriptive data on the anaesthesia and analgesia protocols used by New Zealand veterinarians in first-opinion practice when performing routine canine and feline ovariohysterectomies.

STUDY DESIGN

Cross-sectional survey.

ANIMALS

Not applicable.

METHODS

An online survey was conducted asking respondents for: 1) preoperative patient assessment; 2) preanaesthetic medication and induction drugs used; 3) anaesthesia maintenance drug choices and monitoring equipment used; and 4) postoperative analgesia drug selections and monitoring for ovariohysterectomy performed in healthy adult dogs and cats.

RESULTS

The survey was completed by 472 veterinarians, of whom 282 provided responses for canine ovariohysterectomy and 361 provided responses for feline ovariohysterectomy. Approximately 23% of canine ovariohysterectomies and 13% of feline ovariohysterectomies had preanaesthetic bloodwork performed. There were 74 unique premedication/induction drug combinations reported for canine ovariohysterectomies and 94 for feline ovariohysterectomies. The most commonly used drug combinations were acepromazine, morphine ± propofol and butorphanol, ketamine and medetomidine for canine and feline ovariohysterectomies respectively. Most animals were intubated, and anaesthesia was maintained with isoflurane in oxygen. Use of intravenous catheters, fluid administration, heat support, and monitoring equipment varied. There were 41 unique postoperative analgesia drug combinations reported for canine ovariohysterectomies and 20 for feline ovariohysterectomies. Canine ovariohysterectomies were most commonly administered injectable opioids on the day of surgery followed by 3 days of oral non-steroidal anti-inflammatory drugs (NSAIDs), whereas feline ovariohysterectomies were usually administered a single injection of an opioid or NSAID or both on the day of surgery. Most animals were seen within 7-10 days for re-examination and/or suture removal.

CONCLUSIONS AND CLINICAL RELEVANCE

Veterinarians use a wide range of anaesthesia and analgesia protocols for routine ovariohysterectomies. Further research is needed comparing the safety and efficacy of commonly used protocols to determine whether there are opportunities to improve the level of patient welfare.

Effects of 2% lidocaine hydrochloride solution as a coinduction agent with propofol on cardiopulmonary variables and administered propofol doses in healthy dogs premedicated with hydromorphone hydrochloride and acepromazine maleate

OBJECTIVE

To evaluate the effects of lidocaine as a coinduction agent with propofol on cardiopulmonary variables and administered propofol doses in healthy dogs premedicated with hydromorphone hydrochloride and acepromazine maleate and anesthetized with isoflurane.

ANIMALS

40 client-owned dogs (American Society of Anesthesiologists physical status classification I or II and age ≥ 6 months) scheduled to undergo anesthesia for elective procedures.

PROCEDURES

In a randomized, blinded, controlled clinical trial, dogs received 2% lidocaine hydrochloride solution (2.0 mg/kg [0.9 mg/lb], IV; n = 20) or buffered crystalloid solution (0.1 mL/kg [0.05 mL/lb], IV; 20; control treatment) after premedication with acepromazine (0.005 mg/kg [0.002 mg/lb], IM) and hydromorphone (0.1 mg/kg, IM). Anesthesia was induced with propofol (1 mg/kg [0.45 mg/lb], IV, with additional doses administered as needed) and maintained with isoflurane. Sedation was assessed, and anesthetic and cardiopulmonary variables were measured at various points; values were compared between treatment groups.

RESULTS

Propofol doses, total sedation scores, and anesthetic and most cardiopulmonary measurements did not differ significantly between treatment groups over the monitoring period; only oxygen saturation as measured by pulse oximetry differed significantly (lower in the lidocaine group). Mean ± SD propofol dose required for endotracheal intubation was 1.30 ± 0.68 mg/kg (0.59 ± 0.31 mg/lb) and 1.41 ± 0.40 mg/kg (0.64 ± 0.18 mg/lb) for the lidocaine and control groups, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

No propofol-sparing effect was observed with administration of lidocaine as a coinduction agent for the premedicated dogs of this study. Mean propofol doses required for endotracheal intubation were considerably lower than currently recommended doses for premedicated dogs. (J Am Vet Med Assoc 2020;256:93-101).

Assessment of a commercially available veterinary blood pressure device used on awake and anesthetized dogs

OBJECTIVE

To compare results of a commercially available device for oscillometrically measured blood pressure (OBP) with invasively measured blood pressure (IBP) in awake and anesthetized dogs.

ANIMALS

19 adult dogs (mean ± SD body weight, 17.8 ± 7.5 kg).

PROCEDURES

Blood pressures were measured in dogs while they were awake and anesthetized with isoflurane. The OBP was recorded on a thoracic limb, and IBP was simultaneously recorded from the median caudal artery. Agreement between OBP and IBP was evaluated with the Bland-Altman method. Guidelines of the American College of Veterinary Internal Medicine (ACVIM) were used for validation of the oscillometric device.

RESULTS

In awake dogs, mean bias of the oscillometric device was -11.12 mm Hg (95% limits of agreement [LOA], -61.14 to 38.90 mm Hg) for systolic arterial blood pressure (SAP), 9.39 mm Hg (LOA, -28.26 to 47.04 mm Hg) for diastolic arterial blood pressure (DAP), and -0.85 mm Hg (LOA, -40.54 to 38.84 mm Hg) for mean arterial blood pressure (MAP). In anesthetized dogs, mean bias was -12.27 mm Hg (LOA, -47.36 to 22.82 mm Hg) for SAP, -3.92 mm Hg (LOA, -25.28 to 17.44 mm Hg) for DAP, and -7.89 mm Hg (LOA, -32.31 to 16.53 mm Hg) for MAP. The oscillometric device did not fulfill ACVIM guidelines for the validation of such devices.

CONCLUSIONS AND CLINICAL RELEVANCE

Agreement between OBP and IBP results for awake and anesthetized dogs was poor. The oscillometric blood pressure device did not fulfill ACVIM guidelines for validation. Therefore, clinical use of this device cannot be recommended.

The Influence of Anaesthetic Drugs on the Laryngeal Motion in Dogs: A Systematic Review

Simple Summary

Laryngeal paralysis is secondary to a loss of normal function of the larynx. Older dogs are particularly affected, with normal breathing becoming difficult. A successful diagnosis typically relies on the visualisation of either, complete, or partially absent, laryngeal movements. The use of anaesthesia drugs to provide sedation and stress relief is most commonly necessary during the diagnosis of laryngeal paralysis. While, the excessive administration of anaesthesia drugs may result in absent movements, the ideal anaesthesia regime remains unknown, and the use of sedation is questionable, given the potential for absent laryngeal movements, even in healthy dogs. In this systematic review, we found a potential benefit from using sedation during the evaluation of laryngeal function when compared to injectable anaesthetics only. The respiratory stimulant doxapram was effective in differentiating normal dogs from dogs with laryngeal paralysis but has associated safety hazards.

Abstract

Anaesthetic drugs are commonly used during the evaluation of laryngeal function in dogs. The aim of this review was to systematically analyse the literature describing the effects of anaesthetic drugs and doxapram on laryngeal motion in dogs and to determine which drug regime provides the best conditions for laryngeal examination. PubMed, Google Scholar, and EMBASE databases were used for the literature search up to November 2019. Relevant search terms included laryngeal motion, anaesthetic drugs and dogs. Studies were scored based on their level of evidence (LoE), according to the Oxford Centre for Evidence-based Medicine, and the quality was assessed using the risk-of-bias tool and SIGN-checklist. In healthy dogs, premedication before laryngeal examination provided better examination conditions and maintained overall adequate laryngeal motion in 83% of the studies. No difference in laryngeal motion between induction drugs was found in 73% of the studies but the effects in dogs with laryngeal paralysis remain largely unknown. Doxapram increased laryngeal motion in healthy dogs without serious side effects, but intubation was necessary for some dogs with laryngeal paralysis. Methodological characteristics varied considerably between studies, including the technique and timing of evaluation, number of assessors, study design, drug dose, combinations, route and speed of administration.

The effect of intravenous maropitant on blood pressure in healthy awake and anesthetized dogs

OBJECTIVE

To evaluate the effects of intravenous maropitant on arterial blood pressure in healthy dogs while awake and under general anesthesia.

DESIGN

Experimental crossover study.

ANIMALS

Eight healthy adult Beagle dogs.

PROCEDURE

All dogs received maropitant (1 mg kg-1) intravenously under the following conditions: 1) awake with non-invasive blood pressure monitoring (AwNIBP), 2) awake with invasive blood pressure monitoring (AwIBP), 3) premedication with acepromazine (0.005 mg kg-1) and butorphanol (0.2 mg kg-1) intramuscularly followed by propofol induction and isoflurane anesthesia (GaAB), and 4) premedication with dexmedetomidine (0.005 mg kg-1) and butorphanol (0.2 mg kg-1) intramuscularly followed by propofol induction and isoflurane anesthesia (GaDB). Heart rate (HR), systolic (SAP), diastolic (DAP), and mean blood pressures (MAP) were recorded before injection of maropitant (baseline), during the first 60 seconds of injection, during the second 60 seconds of injection, at the completion of injection and every 2 minutes post injection for 18 minutes. The data were compared over time using a Generalized Linear Model with mixed effects and then with simple effect comparison with Bonferroni adjustments (p <0.05).

RESULTS

There were significant decreases from baseline in SAP in the GaAB group (p < 0.01) and in MAP and DAP in the AwIBP and GaAB (p < 0.001) groups during injection. A significant decrease in SAP (p < 0.05), DAP (p < 0.05), and MAP (p < 0.05) occurred at 16 minutes post injection in GaDB group. There was also a significant increase in HR in the AwIBP group (p < 0.01) during injection. Clinically significant hypotension occurred in the GaAB group with a mean MAP at 54 ± 6 mmHg during injection.

CONCLUSION

Intravenous maropitant administration significantly decreases arterial blood pressure during inhalant anesthesia. Patients premedicated with acepromazine prior to isoflurane anesthesia may develop clinically significant hypotension.

Schirmer Tear Test Value and Corneal Lesions' Incidence during General Anesthesia for Non-Ophthalmic Surgery in Non-Brachycephalic Dogs: A Pilot Study Comparing Three Different Lubricant Eye Drop Formulations

Aim of this blinded, prospective, randomized clinical study was to compare three different lubricant eye drops (LED) in healthy adult dogs undergoing general anaesthesia (GA) for non-ophthalmic surgery. Tear production rate was monitored by means of Schirmer tear test-1 (STT-1), and incidence of post-operative corneal abrasions/ulcerations was detected by corneal staining. A complete ophthalmic examination was performed before premedication, at extubation time and 24 h after GA in twenty-five non-brachycephalic dogs (fifty eyes) undergoing elective orthopaedic or spinal surgery procedures. Dogs were randomly allocated to one of three groups receiving as prophylactic LED either carmellose sodium (GC), or 1% hyaluronic acid (GH), or 0.25% hyaluronic acid (GL). In each eye STT-1 was repeated every hour during GA, before instilling one drop of the assigned LED. In all groups STT-1 values drastically decreased during GA, while 24 h later nine eyes (18%) had STT-1 values lower than 15 mm/minute. All of the three formulations tested were fully effective in preventing corneal ulceration (0% in all groups), while 10% of eyes reported superficial de-epithelialization. Fluorescein staining demonstrated that hourly prophylactic LED application prevented exposure keratopathy during general anesthesia in 90% of the eyes in non-brachycephalic dogs.

Management of veterinary anaesthesia in small animals: A survey of current practice in Quebec

OBJECTIVE

To describe how small animal anaesthesia is performed in French-speaking Eastern Canada, and the variations between practices, in particular based on practice type, veterinarian gender and experience.

DESIGN

Observational study, survey.

SAMPLE

156 respondents.

PROCEDURE

A questionnaire was designed to assess current small animal anaesthesia practices in French-speaking Eastern Canada, mainly in the province of Quebec. The questionnaire was available through SurveyMonkey, and consisted of four parts: demographic information about the veterinarians surveyed, evaluation and management of anaesthetic risk, anaesthesia procedure, monitoring and safety. Gender, year of graduation, and type of practice were tested as potential risk factors. Chi-square exact test was used to study relations between each risk factor, and the effect of the selected risk factor on each response of the survey. For ordinal data, the Cochran-Mantel-Haenszel test was used to maximize power.

RESULTS

Response rate over a period of 3 months was 20.85% (156 respondents). Overall, the way anaesthesia is performed by most respondents does not meet international guidelines, such as patient preparation and evaluation prior to anaesthesia, not using individualised protocols (for 41%), not obtaining intravenous access (12.4% use it for all their anaesthesia in cats, and 30.6% in dogs), lack of patient monitoring at certain intervals for 55% of the responses, and client prompted optional analgesia (for 29% of respondents). Some practices are more compliant than others. Among them, referral centres generally offer better care than general practices.

CONCLUSIONS AND CLINICAL RELEVANCE

The level of care in anaesthesia and analgesia in practices in French-speaking Eastern Canada is concerning, highlighting the need for more sustained continuing education.

Validation of the oscillometric blood pressure monitor Vet20 SunTech in anesthetized healthy cats

OBJECTIVE

To evaluate a veterinary-specific oscillometric noninvasive blood pressure (NIBP) system according to the guidelines of the American College of Veterinary Internal Medicine (ACVIM) Consensus Statement.

STUDY DESIGN

Prospective clinical study.

ANIMALS

A total of 33 client-owned cats (20 females and 13 males).

METHODS

Cats were premedicated with methadone (0.3 mg kg^-1) and alfaxalone (2 mg kg^-1) intramuscularly. After 15 minutes anesthesia was induced with isoflurane (3%) in 100% oxygen by facemask while breathing spontaneously. A 22 gauge catheter was placed in the median caudal artery and systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressures were measured. NIBP measurements were collected by placing the cuff (40% of limb circumference) on the right or left antebrachium. The agreement between the two methods was evaluated with the Bland-Altman methods, and the oscillometric NIBP device was evaluated using the ACVIM guidelines for validation of devices.

RESULTS

Data from 30 of the 33 cats were analyzed. Five paired measurements were taken from each cat, totaling 150 paired measurements. Mean bias (limits of agreements) for SAP, DAP and MAP were 2.7 (-22.7 to 28.1), 0.9 (-22.3 to 24.2) and 1.3 (-20.4 to 23.0). The oscillometric NIBP passed all validation criteria, except correlation which was <0.9 for SAP, DAP and MAP.

CONCLUSIONS AND CLINICAL RELEVANCE

The Vet20 did not meet all validation criteria by the ACVIM. However, all criteria except correlation were met.

2019 AAHA Canine Life Stage Guidelines*

The guidelines are an update and extension of the AAHA Canine Life Stage Guidelines published in 2012. A noteworthy change from the earlier guidelines is the division of the dog’s lifespan into five stages (puppy, young adult, mature adult, senior, and end of life) instead of the previous six. This simplified grouping is consistent with how pet owners generally perceive their dog’s maturation and aging process and provides a readily understood basis for an evolving, lifelong healthcare strategy. The guidelines provide the following recommendations for managing 10 health-related factors at each of the first four canine life stages: lifestyle effect on the patient’s safety, zoonotic and human safety risk, behavior, nutrition, parasite control, vaccination, dental health, reproduction, breed-specific conditions, and a baseline diagnostic profile.

Transcriptome analysis of dog oral melanoma and its oncogenic analogy with human melanoma

Dogs have been considered as an excellent immunocompetent model for human melanoma due to the same tumor location and the common clinical and pathological features with human melanoma. However, the differences in the melanoma transcriptome between the two species have not been yet fully determined. Considering the role of oncogenes in melanoma development, in this study, we first characterized the transcriptome in canine oral melanoma and then compared the transcriptome with that of human melanoma. The global transcriptome from 8 canine oral melanoma samples and 3 healthy oral tissues were compared by RNA-Seq followed by RT-qPCR validation. The results revealed 2,555 annotated differentially expressed genes, as well as 364 novel differentially expressed genes. Dog chromosomes 1 and 9 were enriched with downregulated and upregulated genes, respectively. Along with 10 significant transcription site binding motifs; the NF-κB and ATF1 binding motifs were the most significant and 4 significant unknown motifs were indentified among the upregulated differentially expressed genes. Moreover, it was found that canine oral melanoma shared >80% significant oncogenes (upregulated genes) with human melanoma, and JAK-STAT was the most common significant pathway between the species. The results identified a 429 gene signature in melanoma, which was up-regulated in both species; these genes may be good candidates for therapeutic development. Furthermore, this study demonstrates that as regards oncogene expression, human melanoma contains an oncogene group that bears similarities with dog oral melanoma, which supports the use of dogs as a model for the development of novel therapeutics and experimental trials before human application.

Effect of oral administration of gabapentin on the minimum alveolar concentration of isoflurane in dogs

OBJECTIVE

To determine the effect of oral administration of gabapentin (20 mg/kg) on the minimum alveolar concentration (MAC) of isoflurane in dogs.

ANIMALS

6 healthy adult dogs (3 males and 3 females with a mean ± SD body weight of 24.8 ± 1.3 kg).

PROCEDURES

Each dog was anesthetized twice. Dogs were initially assigned to 1 of 2 treatments (gabapentin [20 mg/kg, PO] followed 2 hours later by anesthesia maintained with isoflurane or anesthesia maintained with isoflurane alone). A minimum of 7 days later, dogs received the other treatment. The MAC of isoflurane was determined by use of an iterative bracketing technique with stimulating electrodes placed in the maxillary buccal mucosa. Hemodynamic variables and vital parameters were recorded at the lowest end-tidal isoflurane concentration at which dogs did not respond to the stimulus. Effect of treatment on outcome variables was analyzed by use of a paired t test.

RESULTS

Mean ± SD MAC of isoflurane was significantly lower when dogs received gabapentin and isoflurane (0.71 ± 0.12%) than when dogs received isoflurane alone (0.91 ± 0.26%). Mean reduction in MAC of isoflurane was 20 ± 14%. Hemodynamic variables did not differ significantly between treatments. Mean time to extubation was significantly less when dogs received gabapentin and isoflurane (6 ± 4 minutes) than when dogs received isoflurane alone (23 ± 15 minutes).

CONCLUSIONS AND CLINICAL RELEVANCE

Oral administration of gabapentin 2 hours before anesthesia maintained with isoflurane had a MAC-sparing effect with no effect on hemodynamic variables or vital parameters of dogs.

Clinical Practice Guidelines: An Opinion of the Legal Implication to Veterinary Medicine

The strengthening of the bond between humans and animals has changed the landscape of the veterinary profession. This has, in turn, led the legal system to assess damages in veterinary malpractice and liability cases more carefully, paying attention to the possibility of using clinical practice guidelines (CPGs) to prove whether the defendant veterinarian contravened or not the standard of care. In this era of evidence-based veterinary medicine, CPGs are becoming an integral part of many aspects of veterinary practice, even if CPGs do not have the force of law and are situated halfway between ethical rules and legal requirements. Although guidelines have been used for several years, there seems to be a general lack of recognition of the medical and legal ramifications of CPGs for veterinarians. This creates ambiguity and inconsistency in the care that veterinary practitioners provide, compromises the care animals receive, and prevents the courts from assessing veterinarian competence in a systematic and rational way. On the basis of these considerations, this article discusses the legal implications of CPGs in veterinary medicine for dogs and cats and explores how the law may treat CPGs in the future. Redefining the CPGs should be a priority for veterinary profession. NOTE: The authors chose to use the terms "companion animal," "pet," and "small animal" interchangeably throughout this article, as all three are commonly in use and refer to the same animals (dogs and cats).

Development of a Robust Canine Welfare Assessment Protocol for Use in Dog (Canis Familiaris) Catch-Neuter-Return (CNR) Programmes

Simple Summary

This paper describes the development of a robust composite welfare assessment tool to evaluate the welfare of free-roaming dogs passing through surgical sterilisation or catch-neuter-return (CNR) programmes. Catch-Neuter-Return programmes are frequently employed by governments and animal welfare charities to control the rising population of free-roaming dogs. Due to the focus on dog population control, individual dog welfare may be compromised through the CNR process, which comprises necessary stressors and harms, including capture, transport, surgery, and social disruption. Using a combination of a modified Delphi analysis and a Hazard Identification and a Critical Control Point analysis, this project described potential hazards to dog welfare during the CNR process and identified critical points where dog welfare could be assessed, and mitigations put in place to improve dog welfare throughout the CNR process. This project resulted in the development of a composite dog welfare assessment tool that will allow the robust assessment of the welfare of free-roaming dogs in CNR programmes and allow CNR projects to benchmark and mitigate hazards to dog welfare.

Abstract

The aim of this study was to develop a welfare assessment tool based on objective, reliable and relevant measures to be applied to individual dogs as they underwent a Catch-Neuter-Return (CNR) programme. A modified Delphi method and Hazard Analysis and Critical Control Points (HACCP) approach was used to develop the composite canine welfare assessment protocol, comprising both animal-based and resource-based measures. This draft welfare assessment protocol was then trialed and refined in existing CNR programmes to identify key control points where individual dog welfare may be moderately or significantly compromised in the CNR process. The results show that animal-based welfare indicators, e.g., pain behaviours, which provide a more direct indication of an animal’s welfare state, require training and skill to recognise, whilst resource-based indicators are simple to measure but act only as indirect measures of welfare. We concluded that whilst CNR projects can potentially improve the health and welfare of free-roaming dogs in the long-term, the risk of short-term welfare harms during the CNR process is high. Thus, it is essential for staff involved in dog population management programmes to assess the welfare state of dogs in CNR and take remedial action to safeguard individual dog welfare.

Effect of midazolam on the quality and duration of anaesthetic recovery in healthy dogs undergoing elective ovariohysterectomy or castration

OBJECTIVE

To determine whether the use of a single dose of midazolam affects quality and duration of the recovery period in healthy dogs undergoing elective castration or ovariohysterectomy.

STUDY DESIGN

Prospective, randomized, placebo-controlled, masked clinical trial.

ANIMAL POPULATION

Seventy-four client-owned dogs undergoing neutering.

METHODS

Following cage demeanour scoring using a simple descriptive scale (SDS), dogs were premedicated with acepromazine (0.03 mg kg^-1) and pethidine (3 mg kg^-1) intramuscularly (quadriceps muscle). Twenty minutes later sedation was scored with an SDS. Male dogs were induced with midazolam (0.25 mg kg^-1) (group M) or an equivalent amount of Hartmann's solution (group P) and propofol intravenously (IV). Female dogs were induced with propofol alone and were administered midazolam (group M) or Hartmann's solution (group P) 5 minutes before intraoperative manipulation of the first ovary. Anaesthesia was maintained with isoflurane in oxygen. Intraoperative analgesia was provided with morphine (0.3 mg kg^-1 IV) prior to the start of surgery. Male dogs were administered intratesticular lidocaine (1 mg kg^-1). All dogs were administered meloxicam (0.2 mg kg^-1 IV) at the end of the procedure, and recovery was scored with an SDS following extubation and 30 minutes later. Time to extubation, head lift, sternal position and standing and complications during recovery were recorded. Data are presented as median (range).

RESULTS

Time to standing was significantly longer in animals in group M [56 (13-179) minutes] than in group P [44 (4-137) minutes], and the early recovery score in group M [3 (2-6)] was overall worse than in group P [3 (1-5)]. Significantly more dogs in group M (n = 30) than in group P (n = 22) displayed hypotension.

CONCLUSIONS AND CLINICAL RELEVANCE

The administration of midazolam prolonged time to standing and had a mild negative effect on the quality of recovery in a pooled population of healthy male and female dogs undergoing neutering.

A multidisciplinary study of pain in cats undergoing dental extractions: A prospective, blinded, clinical trial

This study aimed to evaluate pain scores, analgesic requirements, food intake and serum inflammatory cytokines in cats before and after clinically recommended dental treatment. Twenty-four cats were included in a prospective, blinded clinical trial. Cats were equally divided into minimal (minimal dental treatment) or severe (multiple dental extractions) oral disease groups. They were admitted (day 0) and underwent oral examination/radiographs/treatment under general anesthesia (day 1; acepromazine-hydromorphone-propofol-isoflurane-meloxicam-local anesthetic blocks). Serum inflammatory cytokines were measured on days 0 and 6. Pain was scored using the Glasgow composite measure pain scale-feline (CMPS-F). Rescue analgesia was administered with hydromorphone if CMPS-F ≥ 5/20. Dry and soft food intake (%) during 3 minutes and 2 hours, and daily soft food were calculated. The Cochran-Mantel-Haenszel and Chi-square tests, Spearman’s rank correlation and linear mixed models were used for statistical analysis (alpha = 0.05). Pain scores were significantly increased in cats with severe disease when compared with baseline (up to day 4) and minimal disease (all postoperative time points). Prevalence of rescue analgesia was significantly higher in severe (91.7%) than minimal disease (0%); analgesics were required up to day 3. Pain scores and frequency of rescue analgesia were significantly correlated with the number of tooth extractions, gingival and calculus index. Prevalence of rescue analgesia was significantly correlated with the number of missing teeth, teeth extractions and gingival index. Dry and soft food intake during 3 minutes, and dry food intake during 2 hours were significantly lower in the severe than minimal disease group throughout the study. Some cytokines differed between groups between day 0 and day 6 and were associated with the presence of tooth resorption and number of missing tooth and tooth fractures. Long-term analgesia is required after dental extractions in cats with severe oral disease. This condition reduces food intake and influences serum inflammatory cytokines.

2019 AAHA Dental Care Guidelines for Dogs and Cats*

The 2019 AAHA Dental Care Guidelines for Dogs and Cats outline a comprehensive approach to support companion animal practices in improving the oral health and often, the quality of life of their canine and feline patients. The guidelines are an update of the 2013 AAHA Dental Care Guidelines for Dogs and Cats. A photographically illustrated, 12-step protocol describes the essential steps in an oral health assessment, dental cleaning, and periodontal therapy. Recommendations are given for general anesthesia, pain management, facilities, and equipment necessary for safe and effective delivery of care. To promote the wellbeing of dogs and cats through decreasing the adverse effects and pain of periodontal disease, these guidelines emphasize the critical role of client education and effective, preventive oral healthcare.

Photoplethysmography in dogs and cats: a selection of alternative measurement sites for a pet monitor

OBJECTIVE

Photoplethysmography (PPG) is an increasingly popular health and well-being tool for monitoring heart rate and oxygen saturation. Due to the pigmentation and hairiness of dogs and cats, a pulse oximeter is routinely placed solely on the tongue. As this approach is feasible only for pet monitor use during surgical procedures, we investigate PPG signal quality on several other measurement sites that would be better tolerated by conscious animals.

APPROACH

Acquired PPG signals are analyzed by four signal quality indices: mean baseline, signal power, kurtosis, and tolerance score.

MAIN RESULTS

In dogs, the metacarpus and tail can be substituted for oral pulse oximeter placement since both measurement sites exhibited high PPG signal kurtosis and were considered well-tolerated. In cats, the digit could be used with some limitations.

SIGNIFICANCE

Pet monitors with pulse oximeter probes adjusted to promising measurement sites could enable veterinarians and owners to monitor animals when fully awake.

Effect of oral trazodone on the minimum alveolar concentration of isoflurane in dogs

OBJECTIVE

To determine the effect of oral trazodone on the minimum alveolar concentration (MAC) of isoflurane in dogs.

STUDY DESIGN

Prospective blinded, single-observer, randomized crossover experimental study.

ANIMALS

Six adult (age 6.8 ± 1.6 months) healthy dogs (three males and three females), weighing 24.8 ± 3.4 kg (mean ± standard deviation).

METHODS

Each dog was anesthetized twice with a minimum of 7 days between anesthetic episodes. Dogs were randomly assigned to be administered two treatments in a crossover design: premedication with trazodone (8 mg kg^-1; TRAZ-ISO) orally 2 hours prior to an anesthetic episode or no (ISO). Dogs were anesthetized with intravenous propofol (6 mg kg^-1) and isoflurane in >95% oxygen. Isoflurane MAC was determined using an iterative bracketing technique with electrodes placed in the buccal mucosa. Hemodynamic variables were compared at the lowest end-tidal isoflurane concentration at which each dog did not respond. A paired t test was used to assess the effect of treatment on outcome variables with significance set to a value of p < 0.05.

RESULTS

The MAC concentration (mean ± standard deviation) in dogs administered TRAZ-ISO was 0.85 ± 0.17% compared with 1.02 ± 0.11% in those administered ISO (p = 0.01, 95% confidence interval -0.25 to -0.05), resulting in a mean MAC reduction of 17 ± 12%. There were no differences in hemodynamic variables between treatments.

CONCLUSIONS AND CLINICAL RELEVANCE

Premedication of dogs with oral trazodone (8 mg kg^-1) 2 hours prior to anesthetic induction has a significant isoflurane MAC sparing effect with no significant observed hemodynamic benefit.

The analgesic effects of buprenorphine (Vetergesic or Simbadol) in combination with carprofen in dogs undergoing ovariohysterectomy: a randomized, blinded, clinical trial

Background

Buprenorphine is a potent lipophilic opioid analgesic that is largely used in the multimodal treatment of acute pain. Simbadol (buprenorphine hydrochloride) is the first and only FDA-approved high-concentration formulation of buprenorphine for use in cats. The aim of this study was to evaluate the analgesic efficacy of carprofen in combination with one of two commercial formulations of buprenorphine (Simbadol and Vetergesic, 1.8 mg/mL and 0.3 mg/mL, respectively) in dogs undergoing ovariohysterectomy. Twenty-four dogs were included in a randomized, prospective, controlled, clinical trial. Patients were randomly divided into 2 groups as follows. Dogs were premedicated with acepromazine (0.02 mg/kg) and either 0.02 mg/kg of Vetergesic or Simbadol intramuscularly (Vetergesic group – VG; Simbadol group – SG, respectively; n = 12/group). General anesthesia was induced with propofol and maintained with isoflurane in 100% oxygen. Carprofen (4.4 mg/kg SC) was administered after induction of anesthesia. Heart rate, respiratory rate, blood pressure, pulse oximetry, pain scores using the Glasgow Composite Pain Scale Short Form (CMPS-SF), sedation scores using a dynamic interactive visual analogue scale and adverse events were evaluated before and after ovariohysterectomy by an observer who was unaware of treatment administration. If CMPS-SF scores were ≥ 5/20, dogs were administered rescue analgesia (morphine 0.5 mg/kg IM). Statistical analysis was performed using linear mixed models and Fisher’s exact test (p < 0.05).

Results

Pain and sedation scores and physiological parameters were not significantly different between treatments. Three dogs in VG (25%) and none in SG (0%) required rescue analgesia (p = 0.109). Adverse effects (i.e. vomiting and melena) were observed in two dogs in SG and were thought to be related to stress and/or nonsteroidal anti-inflammatory drug toxicity.

Conclusions

The administration of buprenorphine with carprofen preoperatively provided adequate postoperative analgesia for the majority of dogs undergoing OVH without serious adverse events. Prevalence of rescue analgesia was not significantly different between groups; however, it could be clinically relevant and explained by a type II error (i.e. small sample size). Future studies are necessary to determine if analgesic efficacy after Simbadol and Vetergesic is related to individual variability or pharmacokinetic differences.

Congenital Feline Hypothyroidism With Partially Erupted Adult Dentition in a 10-Month-Old Male Neutered Domestic Shorthair Cat: A Case Report

Congenital feline hypothyroidism was diagnosed in a 10-month-old kitten. The kitten appeared to have disproportionate dwarfism, with the clinical signs of incompletely erupted permanent dentition covered by thickened gingival tissue, short stature, a broad, flattened face, short neck, pendulous abdomen, kitten-like hair coat, and goiter. Hypothyroidism was confirmed with baseline T4, freeT4, and thyroid-stimulating hormone testing. The kitten was treated with thyroid hormone supplementation and monitored. The kitten appeared clinically like a normal healthy cat at 22 months of age on thyroid supplementation.