Guidelines for the Identification, Evaluation, and Management of Systemic Hypertension in Dogs and Cats

Effect of limb and cuff positioning on measurement of arterial blood pressure with an oscillometry device (PetMAP) in anaesthetized cats

Arterial blood pressure (ABP) is often measured with oscillometry during anaesthesia. Changing the height of the measuring cuff with respect to the level of the heart is known to affect oscillometry accuracy in some species, however; this effect has not been investigated in cats. The objective of this study was to determine the effects of raising and lowering the measuring cuff from standard position (level of the heart) on ABP, measured with PetMAP, in anaesthetised cats. ABP readings were obtained from 29 cats with the cuff at standard position (baseline), and 5cm above and below the heart. The end-tidal isoflurane concentrations were maintained constant during data acquisition. There were no differences between baseline values and those measured below the heart, while ABP measured above the heart was consistently lower than baseline for both the thoracic and pelvic limbs (P < 0.001), with absolute differences of 8.2 (2.5 - 14) mmHg and 6.5 (3.0 - 15.0) mmHg, respectively. Systolic ABP readings at the pelvic limb were consistently higher than those at the thoracic limb at standard position (112 ± 26 versus 103 ± 21mmHg, p = 0.010), above (106 ± 22 versus 95 ± 20mmHg, p = 0.003), and below the heart (116 ± 26 versus 107 ± 22mmHg, p = 0.011). This study shows that raising the cuff by 5cm above the heart, which may become necessary during procedural positioning, results in clinically significant underestimation of ABP measured with PetMAP.

Physiological variables for the objective detection of nerve block failure in dogs

OBJECTIVE

To identify physiological variables for objectively detecting nociception indicative of intraoperative peripheral nerve block failure.

STUDY DESIGN

A double-blinded randomized clinical study.

ANIMALS

A sample of 14 male (40.8 ± 12 kg; mean ± standard deviation) and 16 female (34.3 ± 11.4 kg) client-owned dogs.

METHODS

Dogs were randomly assigned to one of three groups for psoas compartment and proximal sciatic nerve blocks (0.2 mL kg-1 per site): guided bupivacaine (GBB), or saline (GSB) block or a blind bupivacaine block (BBB). Guided blocks were performed using an ultrasound-peripheral nerve locator combination. Premedication consisted of medetomidine 0.01 mg kg-1 and morphine 0.3 mg kg-1. General anaesthesia was induced with propofol and maintained with isoflurane in oxygen. Receiver operator characteristic curve analysis was used to compare actual values and change in values of physiological variables between GSB and GBB. The Youden index and associated criterion for each physiological variable were used to determine an objective measure for nociception. Fisher's exact t test, McNemar's test and Cohen's kappa statistical analysis were used to determine association, differences and inter-score reliability between the objective and subjective scoring for BBB.

RESULTS

Cardiovascular variables had good discriminating ability to identify a nociceptive response (p < 0.01). The Youden indices for mean (MAP) and diastolic (DAP) arterial pressure were most reliable in detecting nociception. The highest sensitivity was that of ΔMAP (100%) with good agreement between the subjective and objective scores of Δheart rate or systolic arterial pressure (SAP). The use of ΔMAP, ΔSAP, ΔDAP had the best ability in indicating peripheral nerve block failure (p < 0.001).

CONCLUSIONS AND CLINICAL RELEVANCE

Blood pressure values can detect a response to surgical stimulus in adequately anaesthetized dogs. The use of ΔMAP, ΔSAP or ΔDAP may be considered as objective measures to detect nerve block failure.

Body Condition Scores in Cats and Associations with Systolic Blood Pressure, Glucose Homeostasis, and Systemic Inflammation

BACKGROUND

Feline obesity is the most common nutritional disease in cats. This study aimed to investigate the differences between systolic blood pressure (SBP) and circulating concentrations of glucose, fructosamine, and serum amyloid-A (SAA) in ideal-weight, overweight, and obese cats.

METHODS

The animals were divided into three groups: ideal-weight (BCS 5, N = 20), overweight (BCS 6, N = 20), and obese cats (BCS ≥ 7, N = 20). SBP, circulating concentrations of glucose, fructosamine, and SAA were evaluated.

RESULTS

The SBP values of the ideal-weight, overweight, and obese cats were 140.0 mmHg, 160.0 mmHg, and 160.0 mmHg, respectively. The blood glucose and fructosamine levels for the ideal, overweight, and obese cats were 104.0 mg/dL and 245.0 µmol/L, 123.0 mg/dL and 289.0 µmol/L, and 133.0 mg/dL and 275.0 µmol/L, respectively, for each group. The SAA values were <5 ug/mL in all the groups. The SBP values of the cats with ideal BCS were significantly lower compared to overweight (p = 0.019) and obese (p = 0.001) cats. The blood glucose values of obese cats were higher than those of ideal-weight cats (p = 0.029). There was no statistical difference between the groups for fructosamine and SAA.

CONCLUSIONS

Obese cats had significantly higher SBP and blood glucose concentrations than ideal-weight cats, showing the effect of BSC on these parameters.

Prevalence of Systemic Hypertension and Control of Systolic Blood Pressure in a Cohort of 14 Dogs with Adrenal-Dependent Hypercortisolism during the First Year of Trilostane Treatment or after Adrenalectomy

Hypercortisolism in dogs is frequently associated with systemic hypertension (SH). However, there are no studies evaluating the changes in systolic blood pressure (SBP) in dogs with adrenal-dependent hypercortisolism (ADH) during trilostane treatment or after adrenalectomy and their response to antihypertensive treatments. For this reason, the objectives of this study were to evaluate the changes in SBP in dogs with ADH during the first year of trilostane treatment or after adrenalectomy, the relation with clinical control of hypercortisolism and certain laboratory parameters, and the response to antihypertensive drugs. Fourteen dogs newly diagnosed with ADH were prospectively included and evaluated at diagnosis (T0) and 1, 3, 6, and 12 months after (T1, T3, T6, and T12, respectively). Dogs were classified as hypertensive (HT; SBP ≥ 160 mmHg) and non-hypertensive. In HT dogs, benazepril was considered as the first-line drug, and, if necessary, amlodipine was prescribed. The prevalence of SH at T0 was 79%, and it was reduced to 25% at T12. Blood pressure (BP) was not associated with disease control or selected laboratory parameters at any endpoint. Only 22% of dogs with SH needed more than one drug to normalize their SBP. In all dogs surgically treated that were HT at T0, BP normalized at T3.

Comparison of Thames Medical CAT+ Doppler and SunTech Vet 20 oscillometric devices for non-invasive blood pressure measurement in conscious cats

OBJECTIVES

A comparative assessment of systolic blood pressure (BP) measurement agreement and precision in two commonly used non-invasive BP devices was carried out in conscious cats.

METHODS

Systolic BP measurements were obtained from 50 conscious cats as part of their clinical investigations. All measurements were taken by the same operator and were performed according to the American College of Veterinary Internal Medicine (ACVIM) consensus guidelines. The same cuff location and cuff size were used for paired measurements. The order of device use was randomised, and an arousal score was assigned during each procedure. Precision was assessed using standard deviation and coefficient of variance comparisons. Agreement was assessed using graphical and statistical comparisons of derived 'delta mean' and 'mean of means' data.

RESULTS

A total of 50 cats aged between 3 months and 15 years were enrolled (29 domestic shorthair, seven domestic longhair, three British Shorthair, two Ragdoll, two Sphynx, two Persian, one Siamese, one Burmese, one Russian Blue, one Maine Coon and one Oriental) with a body weight in the range of 1.2-6.2 kg. BP measurements were in the range of 95-179 mmHg. Oscillometric measurements were associated with lower arousal scores. The Doppler device demonstrated superior repeatability precision. Body weight, sex, cuff size, cuff location, arousal score and the order in which the devices were used had no significant effect on precision or agreement. Correlation between the two devices was 0.0837 and agreement was considered clinically acceptable (<10 mmHg) in 32/50 (64%) cats. Of the 18 cats with suboptimal agreement, the oscillometric mean BP was higher in 14 (78%) cats.

CONCLUSIONS AND RELEVANCE

Based on this study sample, suboptimal agreement between paired CAT+ Doppler and SunTech Vet20 oscillometric BP measurements in 36% of conscious cats suggests that these devices should not be used interchangeably. Compared with Doppler, oscillometric measurements were consistently higher, particularly at higher blood pressures. Further studies are required to assess which device has superior accuracy in conscious cats.

Long-term safety of dietary salt: A 5-year ProspEctive rAndomized bliNded and controlled stUdy in healThy aged cats (PEANUT study)

BACKGROUND

High-salt diets promote urine dilution and decrease urolithiasis risk.

OBJECTIVE

Prospectively evaluate the safety of chronic high dietary salt intake (randomized controlled trial).

ANIMALS

Twenty research colony neutered, healthy aged cats (11.5 years [10.0-11.6], median [interquartile range]).

METHODS

Healthy cats were randomized to control or high-salt dry diets (sodium: 1.02 ± 0.16 [mean, SD] and 3.26 ± 0.30 g/Mcal metabolizable energy [ME], respectively; chloride: 2.26 ± 0.33 and 5.71 ± 0.28 g/Mcal ME, respectively), fed for up to 60 months. Assessments included CBC, plasma biochemistry, urinalysis, glomerular filtration rate (GFR), blood pressure, renal and cardiac (conventional Doppler and 2-dimensional color tissue Doppler) imaging, annually. Cats that died or were euthanized underwent necropsy. Diet effects over time were evaluated with linear mixed models.

RESULTS

Follow-up duration (median [Interquartile range]) was similar between the control (38.7 months [28.6-48.2]) and high-salt group (51.4 months [45.7-59.0]). Diet had no significant effect on changes in GFR, blood pressure, plasma creatinine concentration, end-diastolic left ventricular (LV) wall thicknesses, LV internal diameters, LV systolic function, left atrial size, or systolic and diastolic Doppler variables. One control cat developed hypertension. One high-salt group cat developed persistent azotemia. Serial plasma biochemistry and urine specific gravity suggested early chronic kidney disease in 4 nonazotemic cats (2 per group), consistent with necropsy findings.

CONCLUSIONS AND CLINICAL IMPORTANCE

In healthy aged cats, a commercial veterinary diet containing 3.26 ± 0.30 g/Mcal ME sodium was safe with regard to renal and cardiac function for up to 5 years.

Evaluation of the agreement between lingual and thoracic limb noninvasive blood pressure with invasive blood pressure measurements in anaesthetized horses

OBJECTIVE

To evaluate the agreement between noninvasive arterial blood pressure (NIBP) measured from the tongue and thoracic limb with invasive blood pressure (IBP), and to compare NIBP measured from the tongue and thoracic limb in anaesthetized horses.

STUDY DESIGN

Prospective clinical study.

ANIMALS

A group of eight client-owned healthy horses anaesthetized for scheduled procedures, American Society of Anesthesiologists classification I-II, weighing (mean ± standard deviation) 498 ± 91 kg and aged 7.8 ± 6.75 years.

METHODS

Animals were premedicated with intravenous (IV) romifidine (0.04-0.08 mg kg-1) and methadone (0.1 mg kg-1). General anaesthesia was induced IV with ketamine (2.5 mg kg-1) and midazolam (0.05 mg kg-1) and maintained with isoflurane. The facial artery was catheterized for IBP measurements. Systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressures were recorded from the NIBPtongue, NIBPlimb and IBP every 20 minutes during the procedure. Agreement between NIBP and IBP was evaluated based on the American College of Veterinary Internal Medicine criteria and American Association for Medical Instrumentation criteria using the Bland-Altman method.

RESULTS

The mean bias and precision between IBP and NIBP measured from the tongue met the standards for all pressure ranges (< 10 mmHg and < 15 mmHg, respectively). NIBP measurements from the tongue and thoracic limb tended to underestimate IBP measurements. During hypotension, MAPtongue and DAPtongue overestimated IBP, but both precision and accuracy met the criteria. The overall accuracy and precision of NIBPlimb was poorer than NIBPtongue. The percentage of NIBPtongue that differed from IBP by < 10 mmHg was higher than that recorded with NIBPlimb for SAP (46% versus 25%), MAP (77% versus 28%) and DAP (79% versus 19%).

CONCLUSIONS AND CLINICAL RELEVANCE

The tongue is a clinically suitable alternative for assessing arterial blood pressure compared with the thoracic limb and can reliably detect hypotension in healthy anaesthetized horses.

Use of physical examination, electrocardiography, radiography, and biomarkers to predict echocardiographic stage B2 myxomatous mitral valve disease in preclinical Cavalier King Charles Spaniels

INTRODUCTION

Cavalier King Charles Spaniels (CKCS) are predisposed to developing myxomatous mitral valve disease (MMVD). Dogs with stage B2 MMVD benefit from medication.

OBJECTIVES

To develop (1) breed-specific cut-offs for individual screening tests and (2) predictive models utilizing physical examination (PE), ECG, radiograph, and blood-based biomarker variables in combination for identification of echocardiographic stage B2 MMVD in preclinical CKCS.

ANIMALS

Adult, preclinical CKCS not receiving cardiac medications (N = 226).

MATERIALS AND METHODS

Prospective, cross-sectional study. Enrolled CKCS underwent PE, ECG, radiography, Doppler blood pressure measurement, echocardiography, and biomarker testing. Dogs were grouped by MMVD stage using echocardiography only. The discriminatory ability of individual tests to identify stage B2 was assessed, and prediction models were developed using variables derived from four 'tests' (PE, ECG, radiography, and biomarkers).

RESULTS

N-terminal pro-B-type natriuretic peptide (NT-proBNP) and radiographic vertebral heart size (VHS) had the best discriminatory ability of individual diagnostic tests to differentiate stage A/B1 CKCS from stage B2, with an area under the curve (AUC) of 0.855 and 0.843, respectively. An NT-proBNP ≥1138 pmol/L or a VHS ≥11.5 had high specificity for predicting stage B2 (90.1% and 90.6%, respectively). Prediction models incorporating variables from multiple tests had better discriminatory ability than single tests. The four-test prediction model had an AUC of 0.971. Three and two-test models had AUCs ranging between 0.925-0.959 and 0.895-0.949, respectively.

CONCLUSIONS

Both NT-proBNP and VHS have good utility for predicting echocardiographic stage B2 MMVD in CKCS as individual tests. Prediction models incorporating multiple test variables have superior discriminatory ability.

Evaluation of agreement between invasive and non-invasive blood pressure measurement using the PetMAP™ device in rabbits

Background

Measurement of arterial blood pressure is recommended in anaesthetized animals to guide perioperative treatment. Invasive blood pressure measurement is considered the gold standard, however it is also technically challenging, requires specialised equipment and carries certain risks. For these reasons, non-invasive blood pressure measurement devices are commonly used and are expected to provide accurate and reliable results. This requirement is particularly true for rabbits, in whom peri-anaesthetic hypotension is commonly observed and in whom perioperative mortality remains disproportionally high. Several authors have compared different non-invasive devices with invasive measurements in rabbits and have reported contrasting results. However, to date no comparison between invasive measurements and the PetMAP^™ device, that has been designed specifically for veterinary medicine, has been reported.

Aim and hypothesis

The aim of the study was the comparison of invasive blood pressure measurement with PetMAP^™ in rabbits. We hypothesised that PetMAP^™ would show acceptable agreement with the invasive measurements according to the American College of Veterinary Internal Medicine guidelines.

Materials and methods

Sixteen client-owned rabbits presenting for various surgical interventions were included in the study. Invasive measurements were performed by cannulation of an auricular artery. The PetMAP^™ cuff was applied distal to the elbow according to the manufacturer's guidelines. For each measurement with PetMAP^™, three invasive blood pressure values were recorded. The mean of the three invasive values was compared with one value measured with PetMAP^™.

Results

Data collected from 16 rabbits were used for statistical analysis. In the clinical setting, the PetMAP^™ device showed significant overestimation of systolic, diastolic and mean arterial pressure, which were measured in the auricular artery. In addition, the bias was not constant, implying that the device poorly predicted changes in blood pressure.

Conclusion

The PetMAP^™ device did not meet any of the American College of Veterinary Internal Medicine recommendations.

Evaluation of renal values during treatment for heartworm disease in 27 client-owned dogs

BACKGROUND

Canine heartworm disease (CHD) caused by Dirofilaria immitis remains a common preventable disease with increasing incidence in some parts of the USA. The treatment guidelines of the American Heartworm Society (AHS) currently recommend monthly macrocyclic lactone administration, 28 days of doxycycline given orally every 12 h and three injections of melarsomine dihydrochloride (1 injection on day 2 of treatment followed 30 days later by 2 injections 24 h apart). Minocycline has also been utilized when doxycycline is unavailable. The systemic effects of CHD, which particularly impact cardiac and renal function, have been described, with infected dogs often experiencing renal damage characterized by an increase in serum concentrations of renal biomarkers. Although the AHS treatment protocol for CHD has been shown to be safe and effective in most cases, the potential for complications remains. No study as of yet has evaluated changes in symmetric dimethylarginine (SDMA), a sensitive marker of renal function, during treatment for CHD. The purpose of the present study was to evaluate renal function in dogs by measuring serum creatinine and SDMA concentrations during the adulticide treatment period.

METHODS

Serum creatinine and SDMA concentrations were measured in 27 client-owned dogs affected by CHD at the following time points: prior to starting doxycycline or minocycline therapy (baseline), during doxycycline or minocycline therapy (interim), at the time of the first dose of melarsomine (first dose), at the time of the second dose of melarsomine (second dose) and at the dog's follow-up visit after treatment, occurring between 1 and 6 months after completion of therapy (post-treatment). Concentrations of creatinine and SDMA were compared between time points using a mixed effects linear model.

RESULTS

Mean SDMA concentrations following the second dose of melarsomine were significantly lower (-1.80 ug/dL, t-test, df = 99.067, t = -2.694, P-Value = 0.00829) than baseline concentrations. There were no other statistically significant differences in the concentration of either biomarker between the baseline and the other time points in CHD dogs undergoing treatment.

CONCLUSIONS

The results suggest that the current AHS protocol may not have a substantial impact on renal function.

Prevalence of persistent hypertension and situational hypertension in a population of elderly cats in The Netherlands

OBJECTIVES

Systemic arterial hypertension is increasingly recognised and can have serious adverse consequences in cats. Unfortunately, the act of measuring blood pressure itself may cause an increase in blood pressure, known as situational hypertension. It is currently unknown how often this phenomenon occurs. The aim of this study was to evaluate the prevalence of persistent hypertension and situational hypertension in an elderly population of cats in a first-opinion clinic and to assess which factors were associated with systolic hypertension.

METHODS

In this prospective study, systolic blood pressure was measured in 185 cats aged ⩾10 years using the Doppler sphygmomanometry method according to the recommendations of the American College of Veterinary Internal Medicine consensus statement. Age, sex, body weight, body condition score, position during blood pressure measurement and apparent stress level were assessed. If a systolic blood pressure >160 mmHg was found, measurements were repeated to evaluate if persistent hypertension or situational hypertension was present. The first set of blood pressure measurements were used for all the statistical analyses.

RESULTS

The median systolic blood pressure for this population was 140 mmHg. The prevalence of persistent hypertension was at least 14.6% and situational hypertension at least 5.4%. Factors significantly associated with hypertension were age, higher apparent stress levels and a sitting position during measurement. Sex, body weight or body condition score did not significantly influence systolic blood pressure.

CONCLUSIONS AND RELEVANCE

Both persistent hypertension and situational hypertension are common in elderly cats. There are no reliable parameters to distinguish between the two, underlining the importance of a standard protocol and repeating measurements during a follow-up visit when hypertension is found. Age, demeanour and body position during blood pressure measurement influenced blood pressure in this population of elderly cats.

Agreement Between Tongue-Based Oscillometric and Invasive Blood Pressure in Anesthetized Dogs of Various Weights

This study aimed to evaluate the agreement between oscillometric blood pressure (OBP) measured from the tongue and invasive blood pressure (IBP) measured from the dorsal pedal artery in anesthetized dogs of various body weights. Forty-five client-owned dogs undergoing general anesthesia for surgery or imaging scan were included; weights ranged from 2.5 to 42.6 kg. Agreement between paired IBP and OBP during normotension was verified with reference standards used in small animals and humans. The data were stratified by body weight (≤5 kg versus >5 kg). In the >5 kg group (n = 29), the bias ± standard deviation for mean (2.1 ± 7.9 mm Hg) and diastolic pressure (-2.7 ± 7.9 mm Hg) exhibited reliability that met human standards (<5 ± 8 mm Hg). However, in the ≤5 kg group (n = 16), the bias ± standard deviation met only veterinary standards (≤10 ± 15 mm Hg) for mean (3.1 ± 10.2 mm Hg) and diastolic pressure (-2.5 ± 12.6 mm Hg). Agreement for systolic pressure did not meet either standard for both groups. This study demonstrates that tongue-based OBP is a close estimate of mean/diastolic blood pressure in anesthetized dogs (>5 kg) during normotension by small-animal and human criteria.

EVALUATION OF OSCILLOMETRIC BLOOD PRESSURE MEASUREMENT USING A FINGER CUFF IN ANESTHETIZED CHIMPANZEES (PAN TROGLODYTES)

Cardiovascular disease is common among chimpanzees (Pan troglodytes), and serial blood pressure monitoring in conscious animals may improve disease surveillance and guide hypertension treatment strategies. The objective of this study was to compare the accuracy of a noninvasive, oscillometric blood pressure monitor using a finger blood pressure cuff with invasively measured blood pressure in anesthetized chimpanzees. Twelve chimpanzees were anesthetized with tiletamine-zolazepam intramuscularly, intubated, and maintained on inhaled isoflurane to effect. Blood pressure measurements, which included systolic arterial pressure (SAP), mean arterial pressure (MAP), and diastolic arterial pressure (DAP), were collected simultaneously from an oscillometric blood pressure cuff placed on a forelimb digit (FBP) and a direct arterial catheter (IBP) every 5-10 min while anesthetized. One hundred paired samples were collected, and results were compared using Bland-Altman plots and analysis. FBP showed good agreement with IBP for SAP, MAP, and DAP but consistently overestimated values compared with IBP. FBP may be useful for serial blood pressure monitoring in conscious chimpanzees.

Agreement of high-definition oscillometry at two cuff locations with invasively measured arterial blood pressures in anaesthetised cheetahs

OBJECTIVES

To evaluate the agreement between high-definition oscillometry (HDO) used on the metatarsus or tail base with invasive arterial blood pressures measured in the dorsal pedal artery in anaesthetised cheetahs.

STUDY DESIGN

Prospective clinical study.

ANIMALS

A group of 13 captive adult cheetahs.

METHODS

Cheetahs were immobilised with medetomidine (32-45 μg kg^-1) and tiletamine/zolazepam (0.93-1.39 mg kg^-1) administered intramuscularly, and anaesthesia was maintained with either isoflurane in oxygen or continuous propofol infusion. Invasive blood pressure was measured via a 20 gauge intra-arterial catheter in the dorsal pedal artery in the metatarsus and used as a reference method for pressures simultaneously estimated using HDO on the contralateral metatarsus and tail base. Bland-Altman plots (for repeated measurements) and criteria defined by the American College of Veterinary Internal Medicine (ACVIM) were used to compare agreement according to the anatomical location of the cuff, the anaesthetic maintenance agent and magnitude of the blood pressure.

RESULTS

A total of 147 paired measurements were obtained with HDO on the metatarsus and 135 on the tail. Agreement with invasive pressures was better when HDO was used on the tail (rather than on the metatarsus) with all ACVIM criteria being met. Mean bias (a positive bias meaning that HDO overestimated the invasively measured pressures) ± standard deviation of differences for systolic, diastolic and mean arterial pressures were -7.0 ± 13.9, 4.2 ±12.1 and 4.6 ±11.2 mmHg, respectively, for HDO on the tail, and -11.9 ±15.1, 2.8 ±16.5 and 2.1 ±13.2 mmHg, respectively, for HDO on the metatarsus. Agreement was better during isoflurane anaesthesia than propofol, and at lower blood pressures than at higher.

CONCLUSIONS AND CLINICAL RELEVANCE

When used on the tail base of anaesthetised cheetahs, HDO met the ACVIM validation criteria for a noninvasive device, as compared to invasively measured pressures in the dorsal pedal artery.

Comparison of Four Arteries for Invasive Blood Pressure Measurements and Dixtal 2010 Oscillometric Values in Horses Anesthetized With Isoflurane: Does the Artery Matter?

This study evaluated the agreement between invasive blood pressure (IBP) values measured in three different arteries and by an oscillometric device (NIBP) with the ones from the transverse facial artery (FA). Six horses (424.2 ± 40.7 kg) were sedated with xylazine (0.6 mg/kg IV), induced with ketamine (2 mg/kg IV) and midazolam (0.1 mg/kg IV), and maintained with isoflurane (1.2 MAC) for 90 minutes in lateral recumbency. FA, auricular artery (AA), lateral digital artery (LDA), and metatarsal artery (MA) were catheterized, and a standard adult cuff was placed on the tail. IBP and NIBP values were recorded at 30, 45, 60, 75, and 90 minutes of anesthesia. Data were analyzed with Shapiro-Wilk and Repeated-Measures Bland-Altman. Values for FA (mm Hg) were 85.4 ± 10.3 for SAP, 70.6 ± 9.3 for MAP, and 58.5 ± 9.5 for DAP. Mean bias and 95% Limit of agreement (LOA) for AA were -1.7 (-29.0 to 25.6), 2.2 (-18.4 to 22.9), 1.9 (-18.2 to 22.0), for LDA: 1.4 (-25.1 to 27.8), 2.9 (-19.3 to 25.0), 2.3 (-18.4 to 22.9), for MA: -3.2 (-28.3 to 22.0), 2.7 (-16.6 to 22.1), 4.9 (-13.8 to 22.2), and for NIBP: -5.7 (-28.3 to 16.9), 7.9 (-9.5 to 25.3), 17.2 (-2.4 to 36.8), for SAP, MAP and DAP respectively. There is a reasonable bias for IBP values among the arteries evaluated, however a wide LOA, demonstrating the arteries are not interchangeable. NIBP method from Dixtal 2010 results in inaccurate blood pressure values in horses.

Comparison of two multimodal intramuscular anaesthetic protocols in uncooperative feline patients: effects on sedation and echocardiographic measurements

OBJECTIVES

The aims of this study were to compare the sedative effect, feasibility of venous angiocatheter placement and influence on heart rate (HR), systemic blood pressure (SBP) and echocardiographic variables of two multimodal anaesthetic protocols in uncooperative cats; and to compare their influence on HR, SBP and echocardiographic variables 20 mins after sedation and after elective ovariectomy.

METHODS

Eighteen stray female cats randomly received intramuscular (IM) ketamine (2 mg/kg) and methadone (0.3 mg/kg) plus dexmedetomidine (7 µg/kg; group D, n = 9) or alfaxalone (2 mg/kg; group A, n = 9). A sedation score (0-15 [from none to good sedation]) was assigned at 5 mins, 10 mins, 15 mins and 20 mins after IM injection. Venous angiocatheter placement and echocardiographic examination feasibility scores (both from 0 to 3 [from very difficult to very easy]) were recorded at 20 mins. Echocardiography, HR and blood pressure measurements (Doppler and oscillometric methods) were performed at 20 mins and at the end of surgery.

RESULTS

Sedation and angiocatheter feasibility scores did not differ significantly between groups (P >0.05); the feasibility score of echocardiographic examination was higher in cats in group D (P = 0.01). HR was higher in group A at 20 mins and after surgery (P <0.05). The systolic arterial pressure obtained with the Doppler method was statistically significantly higher in cats in group D than in group A at 20 mins (P = 0.01), while postoperatively there were no differences between groups. Cats in group D showed significantly higher atrial diameters (P <0.05) and slower atrial flows (P = 0.04) compared with group A; ventricular thickness and atrial function did not differ between groups (P >0.05). Most echocardiographic variables were not different at 20 mins vs postoperatively.

CONCLUSIONS AND RELEVANCE

Both protocols allowed for effective sedation; however, cats in group D presented alterations in some echocardiographic measurements; the use of alfaxalone, combined with ketamine and methadone, is recommended to obtain a reliable echocardiographic evaluation in uncooperative cats.

Manifestations of hypertensive encephalopathy in cats

OBJECTIVES

Hypertensive encephalopathy in cats is an important entity but is underestimated in clinical practice. This could be explained, in part, by non-specific clinical signs. The objective of this study was to characterise the clinical manifestations of hypertensive encephalopathy in cats.

METHODS

Cats with systemic hypertension (SHT) recognised by routine screening, associated with underlying predisposing disease or a clinical presentation suggestive of SHT (neurological or non-neurological), were prospectively enrolled over a 2-year period. Confirmation of SHT was based on at least two sets of measurements of systolic blood pressure >160 mmHg by Doppler sphygmomanometry.

RESULTS

Fifty-six hypertensive cats with a median age of 16.5 years were identified; 31 had neurological signs. In 16/31 cats, neurological abnormalities were the primary complaint. The other 15 cats were first presented to the medicine or ophthalmology service, and neurological disease was recognised based on the cat's history. The most common neurological signs were ataxia, various manifestations of seizures and altered behaviour. Individual cats also showed paresis, pleurothotonus, cervical ventroflexion, stupor and facial nerve paralysis. In 28/30 cats, retinal lesions were detected. Of these 28 cats, six presented with a primary complaint of visual deficits, and neurological signs were not the primary complaint; nine presented with non-specific medical issues, without suspicion of SHT-induced organ damage; in 13 cats, neurological issues were the primary complaint and fundic abnormalities were detected subsequently.

CONCLUSIONS AND RELEVANCE

SHT is common in older cats and the brain is an important target organ; however, neurological deficits are commonly ignored in cats with SHT. Gait abnormalities, (partial) seizures and even mild behavioural changes should prompt clinicians to consider the presence of SHT. A fundic examination in cats with suspected hypertensive encephalopathy is a sensitive test to support the diagnosis.

EVALUATION OF AGREEMENT BETWEEN OSCILLOMETRIC AND DIRECT BLOOD PRESSURE MEASUREMENTS IN ANESTHETIZED TIGERS (PANTHERA TIGRIS)

Noninvasive blood pressure measurement is commonly performed with oscillometry; however, this technique provides clinically helpful information only if it is representative of the gold standard. Agreement between direct and oscillometric blood pressure measurements were performed in 14 anesthetized, captive tigers (Panthera tigris). A cuff, placed around the tail base and connected to a multiparameter monitor, was used to measure arterial blood pressure oscillometrically and provided systolic, mean, and diastolic pressures. At the same time, direct blood pressures were obtained from a dorsal pedal arterial catheter, and the oscillometric and direct readings were considered paired data points. Agreement between the two methods was evaluated by Bland-Altman plots. All animals completed the study and provided 196 paired data points. The bias (mm Hg) for systolic, mean, and diastolic arterial pressures was -3.7, -0.8, and -1.6, respectively. Limits of agreement (mm Hg) for systolic, mean, and diastolic arterial pressures were -31 to 24, -29 to 27, and -29 to 26, respectively. Oscillometry provided an acceptable amount of readings within 10 and 20 mm Hg of the gold standard. The oscillometric technique provided reasonable agreement with direct measurements. Therefore, in the conditions used in this study, oscillometric blood pressure measured via the ventral coccygeal artery provided reasonable estimates of invasive blood pressure in anesthetized tigers.

Urinary liver-type fatty acid-binding protein in clinically healthy elderly cats: Evaluation of its potential to detect IRIS stage 1 chronic kidney disease and borderline proteinuria

BACKGROUND

Urinary liver-type fatty acid-binding protein (uL-FABP) is a promising biomarker to detect early chronic kidney disease (CKD) in cats. Few healthy cats show increased uL-FABP for unknown reasons.

OBJECTIVES

The objective of this study was to evaluate uL-FABP in a large healthy elderly cat population comparing cats with and without International Renal Interest Society (IRIS) stage 1 CKD and with and without borderline proteinuria.

METHODS

This was a cross-sectional study. One hundred ninety-six clinically healthy client-owned cats of ≥7 years old were subdivided based on two criteria: (1) having either IRIS stage 1 CKD or no evidence of CKD and (2) having borderline proteinuria or no proteinuria. Urinary L-FABP was measured using a validated commercially available feline L-FABP ELISA.

RESULTS

Overall, uL-FABP was detectable in 6/196 (3%) healthy elderly cats. For the first subdivision, nine (5%) cats had IRIS stage 1 CKD, 184 cats had no evidence CKD and three cats were excluded. All cats with IRIS stage 1 CKD had uL-FABP concentrations below the detection limit, whereas 6/184 (3%) cats without IRIS stage 1 CKD had detectable uL-FABP concentrations (median 1.79 ng/ml, range 0.79-3.66 ng/ml). For the second subdivision, 47 (24%) cats had borderline proteinuria, 147 cats had no proteinuria and two cats were excluded. One of the borderline proteinuric cats had a detectable uL-FABP concentration, whereas the other five cats with detectable uL-FABP concentrations were non-proteinuric.

CONCLUSION

With the current assay, the screening potential of uL-FABP as an early biomarker for feline CKD is limited as uL-FABP was rarely detected in clinically healthy elderly cats independently of the presence of either IRIS stage 1 CKD or borderline proteinuria.

Key nutrients important in the management of canine myxomatous mitral valve disease and heart failure

The most common cause of heart failure in dogs is myxomatous mitral valve disease (MMVD), which accounts for approximately 75% of canine heart disease cases and is especially common in smaller dogs. Although low-sodium diets have been recommended for humans with heart diseases for decades, there is little evidence to support this practice in dogs. In recent years, however, it has become clear that other nutrients are important to heart health. Dogs with heart disease secondary to MMVD experience patterns of metabolic changes that include decreased mitochondrial energy metabolism and ATP availability, with increased oxidative stress and inflammation. These changes occur early in disease and progress with worsening heart disease. Key nutrients that may support normal function and address these changes include omega-3 fatty acids, medium-chain triglycerides, magnesium, antioxidants including vitamin E and taurine, and the amino acids methionine and lysine. The long-chain omega-3 fatty acids provide anti-inflammatory, antithrombotic, and other benefits. Medium-chain fatty acids and ketones derived from medium-chain triglycerides provide an alternative energy source for cardiac mitochondria and help reduce free radical production. Magnesium supports mitochondrial function, normal cardiac rhythm, and provides other benefits. Both vitamin E and taurine counter oxidative stress, and taurine also has direct cardiac benefits. Dogs with MMVD have reduced plasma methionine. Methionine and lysine are important for carnitine production as well as other functions. This article reviews the evidence supporting the functions and benefits of these and other nutrients in MMVD and other cardiac conditions.

Effects of a Novel Gel Formulation of Dog Appeasing Pheromone (DAP) on Behavioral and Physiological Stress Responses in Dogs Undergoing Clinical Examination

Simple Summary

Safeguarding the health of dogs presupposes undergoing regular veterinary visits (VVs). However, the VV can be emotionally challenging, thus impairing the welfare of the patient, also reducing dog and owner compliance. The fear and anxiety experienced by the dogs evokes behavioral and physiological stress responses for adaptive purposes. It is therefore desirable to lower the stress from the visit. With this intent, we tested a gel formulation of a synthetic analogue of the appeasing pheromone secreted by bitches, the dog appeasing pheromone (DAP), as a situational support to improve the perception of the stay in the waiting room and the physical examination. In the waiting room, the dogs exposed to DAP exhibited changes in their behavior, namely significant decrease in lip licking, increase in panting, and nearly significant reduction of low body postures. On the examination table, neither behavioral nor physiological differences were found. DAP did not alter markedly the stress behavior and physiology of dogs during a VV, maybe due to a stress level exceeding the potential efficacy of the product. However, the change of a few stress-associated behaviors suggests that DAP could contribute to improving the welfare of dogs staying in the waiting room before the physical examination.

Abstract

The veterinary visit is necessary for safeguarding the health of dogs, but it can be stressful and threaten both the welfare of the patient and the accuracy of the examination. This randomized, triple-blind, placebo-controlled, crossover study aims at evaluating how dog appeasing pheromone (DAP) in a novel gel formulation influences the behavioral and physiological stress responses of 28 dogs undergoing a standardized clinical examination, while staying in the waiting room (WR) and visited in the examination room (ER). Behavioral responses were studied through behavioral categories and subjective scales (WR and ER). Autonomic response considered heart rate (WR and ER), blood pressure (WR and ER), respiratory rate (ER), and rectal temperature (ER). Neuroendocrine response considered salivary cortisol (WR and ER). In the waiting room, the use of DAP was associated with a significant reduction of lip licking (p = 0.0189), an increase in panting (p = 0.0276), and a reduction close to significance (p = 0.0584) of low body postures. No significant differences were observed within the physiological responses. In the examination room, neither behavioral nor physiological differences were found.

Echocardiography and MALDI-TOF Identification of Myosin-Binding Protein C3 A74T Gene Mutations Involved Healthy and Mutated Bengal Cats

This study aimed to identify the potential peptide candidates and expected proteins associated with MYBPC3-A74T gene mutations in Bengal cats and determine if peptidome profiles differ between healthy controls and cats with MYBPC3-A74T gene mutations. All animals were evaluated using echocardiography. DNA was isolated and followed by the screening test of MYBPC3 gene mutation. The MALDI-TOF mass spectrometry was conducted for analyzing the targeted peptide and protein patterns. The expected protein candidates were searched for within the NCBI database. Our results demonstrated that the MYBPC3-A74T gene mutation was dominant in Bengal cats but not in domestic shorthair cats. Correlations between baseline characteristics and echocardiographic parameters were discovered in Bengal cats. Mass spectrometry profiles of the candidate proteins were suspected to accompany the cat with the MYBPC3-A74T gene mutation, involving integral protein–membrane, organization of nucleus, DNA replication, and ATP-binding protein. Therefore, MYBPC3-A74T gene mutations occur frequently in Bengal cat populations. The high incidence of homozygotes for the mutation supports the causal nature of the MYBPC3-A74T mutation. In addition, peptidomics analysis was established for the first time under this condition to promise a complementary technique for the future clinical diagnosis of the MYBPC3-A74T mutation associated with physiological variables and cardiac morphology in cats.

Investigating the Relationship Between Cardiac Function and Insulin Sensitivity in Horses: A Pilot Study

Metabolic syndrome in humans is commonly associated with cardiovascular dysfunction, including atrial fibrillation and left ventricular diastolic dysfunction. Although many differences exist between human and equine metabolic syndrome, both of these conditions share some degree of insulin resistance. The aims of this pilot study were to investigate the relationship between insulin sensitivity and cardiac function. Seven horses (five mares, two geldings, aged 17.2 ± 4.2 years, weight 524 ± 73 kg) underwent insulin-modified frequently sampled intravenous glucose tolerance testing to determine insulin sensitivity (mean 2.21 ± 0.03 × 10−4 L/min/mU). Standard echocardiograms were performed on each horse, including two-dimensional, M-mode, and pulse-wave tissue Doppler imaging. Pearson and Spearman correlation analyses were used to determine the association of insulin sensitivity with echocardiographic measures of cardiac function in 5 horses. Insulin sensitivity was found to be significantly correlated with peak myocardial velocity during late diastole (r = 0.89, P = 0.0419), ratio between peak myocardial velocity in early and late diastole (r = −0.92, P = 0.0263), isovolumetric relaxation time (r = −0.97, P = 0.0072), and isovolumetric contraction time (ρ = −0.90, P = 0.0374). These preliminary data suggest that decreased insulin sensitivity is correlated with alterations in both systolic and diastolic function, as measured with tissue Doppler imaging (TDI). Due to the small sample size of this study, the relationship between insulin sensitivity and myocardial function in horses requires further investigation.

Seronegative Myasthenia Gravis with Concomitant SARS-CoV-2 Infection in a Dog

Myasthenia gravis (MG) is a disorder of neuromuscular transmission affecting the neuromuscular junction. The majority of cases involve an autoimmune attack against AChR, but a limited number of patients are seronegative for AChR antibodies. Viral infection is incriminated as a trigger for MG occurrence, and in a limited number of reports, infection with SARS-CoV-2 was found to be associated with MG expression in humans. In this report, we describe case of seronegative generalized MG in a 2-year-old crossbred female dog associated with SARS-CoV-2 infection due to close exposure to an infected owner.

Use of a human wrist blood pressure monitor for arterial blood pressure measurements in normotensive conscious dogs in comparison to veterinary high-definition oscillometry

Background

The gold standard in canine blood pressure (BP) measurement is the invasive method; however, non‐invasive blood pressure measurement techniques (NIBP) are more commonly used. The lack of small, lightweight, cheap, fast and portable NIBP still remains a point to improve in the emergency setting.

Key Findings

A human wrist blood pressure (WBP) device was evaluated in comparison with the veterinary high‐definition oscillometry (HDO) in conscious normotensive dogs. Systolic and diastolic BPs were evaluated in two groups of dogs. The bias, the limits of agreement and correlation between variables were calculated. Twenty‐five and 36 dogs were, respectively, included in Study No. 1 (dogs weighting ≥10 kg) and 2 (dogs weighting ≥20 kg). In both studies, correlation between the two devices was moderate. A better agreement was displayed for diastolic pressure and poor precision for both systolic and diastolic pressures measurements (as determined by wide limits of agreement). The WBP method underestimated both the systolic and diastolic BP with respect to the HDO method. The inclusion of bigger dogs (Study No. 2) with limb circumference more like to human limb dimension did not improve the agreement between considered methods.

Significance

The human WBP monitor considered is not suitable to replace the commonly used veterinary HDO for in‐clinic BP monitoring in normotensive conscious dogs.

Survival of dogs with pituitary-dependent hyperadrenocorticism treated twice daily with low doses of trilostane

BACKGROUND

Twice daily low trilostane doses have proven to be effective to manage canine Cushing's syndrome. However, survival and prognostic factors in dogs treated with this protocol have not been evaluated. The aim of the study was to evaluate survival and prognostic factors, including systolic blood pressure (SBP) at diagnosis, in dogs with pituitary-dependent hypercortisolism (PDH) treated with low trilostane doses.

METHODS

Medical records of 91 dogs newly diagnosed with PDH initially treated with 0.2-1.1 mg/kg of trilostane twice daily were retrospectively included. Survival times were calculated using the Kaplan-Meier estimator. Univariable and multivariable analysis were performed using the Cox proportional hazard regression analysis.

RESULTS

Overall, median survival was 998 days (range 26-1832 days, 95% confidence interval = 755-1241 days). In the multivariable analysis, age (hazard ratio [HR] = 1.337, p < 0.001), presence of calcinosis cutis (HR = 5.271, p < 0.001), body condition score (BCS) ≤3/9 (HR = 8.100, p < 0.001) and higher platelet count (HR = 1.002, p = 0.022) were negatively correlated with survival. SBP was not associated with survival.

CONCLUSIONS

Low-dose trilostane treatment twice daily provides slightly longer survival than previously reported for dogs with PDH treated once or twice daily at higher doses. Older age, presence of calcinosis cutis, low BCS and higher platelet count, but not systemic hypertension, are predictive of poorer prognosis in dogs with PDH.

Agreement of High-Definition Oscillometry (HDO) and Invasive Blood Pressure Measurements at a Metatarsal Artery in Isoflurane-Anaesthetised Horses

Simple Summary

In equine anaesthesia, valid and reliable blood pressure monitoring is crucial for adequate blood pressure management. Various non-invasive blood pressure monitors have been studied with varying results. High-definition oscillometry (HDO) promises greater accuracy than conventional oscillometric devices. With the cuff placed at the tail, the monitor gives satisfactory readings in normotensive anaesthetised horses, while for measuring low and high blood pressure, reliability was inadequate. To date, high-definition oscillometry has not been evaluated at the easily accessible equine metatarsal area. Therefore, the objective of this study was to assess agreement between HDO and invasive blood pressure, both obtained at a metatarsal artery at different blood pressure ranges in anaesthetised horses. Additionally, compliance with the American College of Veterinary Internal Medicine consensus guidelines was assessed. Agreement of HDO and invasive blood pressure was acceptable for mean arterial blood pressure during normotension only. During hypotension and hypertension, measurements were not valid. The monitor failed to meet most of the consensus validation criteria. Consequently, invasive blood pressure measurement remains preferable in haemodynamically unstable patients.

Abstract

High-definition oscillometry (HDO) over the metatarsal artery (MA) in anaesthetised horses has not yet been evaluated. This study aimed to assess agreement between HDO and invasive blood pressure (IBP) at the metatarsal artery, and to evaluate compliance with the American College of Veterinary Internal Medicine (ACVIM) consensus guidelines. In this experimental study, 11 horses underwent general anaesthesia for an unrelated, terminal surgical trial. Instrumentation included an IBP catheter in one and an HDO cuff placed over the contralateral MA, as well as thermodilution catheters. Systolic arterial pressure (SAP), mean arterial pressure (MAP), diastolic arterial pressure (DAP), and cardiac output were measured simultaneously. Normotension (MAP 61–119 mmHg) was maintained during the surgical study. Subsequently, hypotension (MAP ≤ 60 mmHg) and hypertension (MAP ≥ 120 mmHg) were induced pharmacologically. For MAP, the agreement between HDO and IBP was acceptable during normotension, while during hypotension and hypertension, IBP was overestimated and underestimated by HDO, respectively. The monitor failed to meet most ACVIM validation criteria. Consequently, if haemodynamic compromise or rapid blood pressure changes are anticipated, IBP remains preferable.

Bias Associated with Peripheral Non-Invasive Compared to Invasive Arterial Blood Pressure Monitoring in Healthy Anaesthetised and Standing Horses Using the Bionet BM7Vet

To compare arterial blood pressure (ABP) measured invasively (IBP) to ABP measured non-invasively (NIBP) via oscillometry in healthy anaesthetised and standing horses using the Bionet BM7Vet. Fourteen horses were anaesthetised for elective procedures (anaesthetised group) and 10 horses were enrolled for standing blood pressure manipulation (standing group). In both groups, IBP and NIBP-corrected to heart level were measured every 3 min using the Bionet BM7Vet. The overall mean difference (bias), standard deviation and limits of agreement (LOA) were calculated for paired IBP and NIBP systolic (SAP), mean (MAP) and diastolic (DAP) blood pressure measurements. In anaesthetised horses, the NIBP cuff was placed at either the proximal tail base or the metacarpus. Invasive MAP was used to retrospectively characterise measurements into hypotensive (≤70 mm Hg), normotensive (71–110 mm Hg) or hypertensive (≥111 mm Hg) subgroups. In standing horses, the NIBP cuff was placed at the tail base only and invasive MAP was manipulated to achieve hypertension (≥126 mm Hg) and hypotension (≤90 mm Hg) using phenylephrine and acepromazine, respectively. When measuring NIBP at the tail in anaesthetised horses, the Bionet BM7Vet failed on 8/185 occasions and overestimated SAP, MAP and DAP during hypotension and normotension. The biases (lower, upper LOA) for MAP were −11.4 (−33.3, 10.5) and −6.0 (−25.8, 13.8) mm Hg, respectively. Hypertension could not be evaluated. When measuring NIBP at the metacarpus in anaesthetised horses, the Bionet BM7Vet failed on 24/65 occasions and underestimated SAP, MAP and DAP when all ABP subgroups were combined. The bias (lower, upper LOA) for pooled MAP was 3.6 (−44.3, 51.6) mm Hg. When measuring NIBP at the tail in standing horses, the Bionet BM7Vet failed on 64/268 occasions and underestimated SAP, MAP and DAP during hypotension, normotension and hypertension. The biases (lower, upper LOA) for MAP were 16.3 (−10.5, 43.1), 16.6 (−19.5, 52.7) and 30.0 (−8.1, 68.0) mm Hg, respectively. Monitoring NIBP on the Bionet BM7Vet in anaesthetised horses overestimated ABP at the tail and underestimated ABP at the metacarpus. The device inaccurately detected hypotension and should be used cautiously. In standing horses, the Bionet BM7Vet underestimated ABP at the tail, especially during pharmacologically induced hypertension.

Efficacy of high-intensity interval training compared with moderate-intensity continuous training on maximal aerobic potency in dogs: Trial protocol for a randomised controlled clinical study

BACKGROUND

High-intensity interval training (HIIT) is a more efficient method to improve exercise capacity than moderate-intensity continuous training (MICT) because of its greater physiological stimulus.

OBJECTIVE

The aim of this protocol is to evaluate the efficacy of HIIT on maximal aerobic potency in dogs as compared to MICT.

METHODS

This protocol is for a randomised, blinded controlled clinical trial, with three parallel groups for the purpose of demonstrating superiority. Thirty dogs aged between 12 and 84 months of both sexes and different breeds will be included. Dogs, before initiating and after finalising the training will perform an incremental exercise test on a treadmill to obtain maximal speed and lactate threshold; resting parameters of heart and respiratory rate, left ventricle chamber and systolic function will be measured. Dogs assigned to each intervention will endure a 42-min session of HIIT or MICT during 12 weeks. HIIT comprises four intervals of 4 min each at a load of 85%, alternating with a 4-min resting period. MICT group will have a continuous load of 60%. The control group will remain in a cage. An intention-to-treat statistical analysis will be implemented. Analysis of covariance will be used to estimate the effect of HIIT compared with MICT training on maximal aerobic potency, aerobic resistance, systolic function at rest, left ventricle chamber measurements and indexes, respiratory rate and HR at rest.

CONCLUSION

Significant time and effort are invested into training sports/working dogs, which could benefit from improving physical capacity by means of the HIIT methodology.

Evaluation of the tongue for oscillometric measurement of arterial pressure in anesthetized Beagle dogs

OBJECTIVE

To evaluate the agreement between oscillometric blood pressure (OBP) measured from the tongue and invasive blood pressure (IBP), and to compare OBPs measured from the tongue with OBPs measured from the pelvic limb and tail.

STUDY DESIGN

Prospective experimental study.

ANIMALS

A total of eight adult Beagle dogs weighing 11.1 ± 1.2 kg.

METHODS

Animals were premedicated with intravenous (IV) acepromazine (0.005 mg kg^-1). Anesthesia was induced with alfaxalone (3 mg kg^-1) IV and maintained with isoflurane. The dorsal pedal artery was catheterized for IBP measurements. Systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressure were simultaneously measured from the tongue, pelvic limb and tail. Based on invasive SAP, hypertension (>140 mmHg), normotension (90-140 mmHg) and hypotension (<90 mmHg) were induced by controlling end-tidal isoflurane concentrations and/or dobutamine/dopamine administration. Agreement between paired IBP and OBP measurements was analyzed with reference standards for noninvasive blood pressure devices used in small animals and humans.

RESULTS

Regardless of cuff placement, the mean bias ± standard deviation between IBP and OBP met veterinary (≤10 ± 15 mmHg) and human (<5 ± 8 mmHg) standards for MAP and DAP. SAP measurements provided by the OBP device showed unacceptable agreement with IBP, and the bias between methods increased at higher blood pressures, regardless of cuff site. During hypotension, tongue OBP showed the largest percentage of absolute difference <10 mmHg in relation to IBP for SAP (90%), MAP (97%), and DAP (93%), compared with pelvic limb (60%, 97% and 82%, respectively) and tail OBP (54%, 92% and 77%, respectively).

CONCLUSIONS AND CLINICAL RELEVANCE

The tongue is a clinically useful site for measuring OBP in anesthetized Beagle dogs, providing reliable estimates of MAP and DAP. The tongue could replace other cuff placement sites and may be a relatively suitable site for assessing hypotension.

Thiobarbituric acid reactive substances in dogs with spontaneous hypercortisolism

Thiobarbituric acid reactive substances (TBARS) are laboratory markers of oxidative stress, which can be used to evaluate the lipid peroxidation that characterizes cell membrane damage caused by excess free radicals. This prospective study aimed to assess TBARS as a parameter of lipid peroxidation in dogs with spontaneous hypercortisolism (HC) at the time of diagnosis, and after trilostane treatment. Furthermore, it aimed to investigate the correlations between TBARS levels, and laboratory and cardiovascular parameters. Sixteen dogs with HC were evaluated at 3 different time points: At diagnosis (T0), 6 mo after treatment (T1), and 12 mo after trilostane treatment (T2). A control group (n = 20) of dogs with a demographic profile similar to the HC group, but considered healthy was selected and evaluated. There was a significant difference (P < 0.001) in TBARS levels between the HC group at diagnosis (4.38 ± 1.16 nmoles MDA/mg protein) and the control group (2.15 ± 0.45 nmoles MDA/mg protein). Dogs in the HC group exhibited a significant reduction (P < 0.001) in TBARS levels after treatment. There was no significant difference in TBARS levels between the control group and the HC group at T1 and T2 evaluation. TBARS positively correlated with left atrial dimensions and hematocrit. The study demonstrates that lipid peroxidation is increased in canine HC and suggests that control of the disease is beneficial to normalize the state of oxidative stress.

Effects of vatinoxan on xylazine-induced pulmonary alterations in sheep

It was hypothesized that premedication with vatinoxan, a peripheral α₂ -adrenoceptor antagonist, would mitigate xylazine-induced pulmonary alterations in sheep. Fourteen adult sheep were allotted into two equal groups and premedicated with either vatinoxan (750 µg/kg IV) or saline and sedated 10 min later with xylazine (500 µg/kg IV). Arterial oxygen saturation (SpO₂ ) was measured and respiratory rate (RR) counted at intervals. The sheep were euthanized with IV pentobarbital 10 min after xylazine administration. The severity of pulmonary parenchymal alterations was assessed and graded grossly and histologically and correlations of the morphological changes with SpO₂ evaluated. Following xylazine injection, SpO₂ was significantly higher and RR significantly lower with vatinoxan than with saline and the sheep administered vatinoxan exhibited significantly smaller quantities of tracheal foam than those receiving saline. No significant differences in macroscopic oedema scores were detected between treatments. In contrast, the vatinoxan-treated animals exhibited significantly graver microscopic interstitial alveolar oedema and haemorrhage than saline-treated animals. The histological severity scores did not correlate with changes in SpO₂ . In conclusion, xylazine induced a marked reduction in SpO₂ which was abolished by the prior administration of vatinoxan. The histologically detected alterations after pentobarbital euthanasia with vatinoxan premedication need to be studied further.

Use of Amlodipine in Psittacine Birds: 5 Cases (2010-2018)

Amlodipine is a calcium channel blocker shown to be effective in lowering blood pressure with minimal adverse effects in mammals. To provide a retrospective evaluation of amlodipine use in psittacine birds, medical records were reviewed for all avian patients prescribed amlodipine for treatment for the presumptive diagnosis of hypertension, based on clinical signs and indirect blood pressure measurements. Five birds were treated with amlodipine between 2010 and 2018. The median age was 33 years (range, 22-37 years) and 3/5 birds presented for ataxia or seizures. The median indirect systolic blood pressure at diagnosis was 243 mm Hg (range, 200-275 mm Hg). In 3/5 birds, amlodipine was the only drug prescribed, whereas, in 2/5 birds, enalapril was also prescribed in addition to amlodipine. In addition to the prescription of enalapril, blood pressure measurements were obtained indirectly, which are variables to be considered in this report. The initial median dose of amlodipine prescribed was 0.4 mg/kg (range, 0.1-0.4 mg/kg) PO q24h. In 3/5 birds, amlodipine administration was increased either in dose or frequency. Median follow-up time was 25 months (range, 2-55 months) after the initiation of amlodipine treatment. Owners in all 5 cases reported improvement of clinical signs by a median time of 2 months (range, 1-15 months). Three of 5 birds (60%) demonstrated a decreasing trend in blood pressure during the first 6 months after treatment with amlodipine was started (average, ≥20% decrease). Prospective, controlled studies are needed to investigate the efficacy of amlodipine in psittacine birds.

2021 AAFP Feline Senior Care Guidelines

The '2021 AAFP Feline Senior Care Guidelines' are authored by a Task Force of experts in feline clinical medicine and serve as an update and extension of those published in 2009. They emphasize the individual patient evaluation and the process of aging, with references to other feline practice guidelines for a more complete discussion of specific diseases. Focusing on each cat encourages and empowers the owner to become a part of the cat's care every step of the way. A comprehensive discussion during the physical examination and history taking allows for tailoring the approach to both the cat and the family involved in the care. Videos and analysis of serial historical measurements are brought into the assessment of each patient. These Guidelines introduce the emerging concept of frailty, with a description and methods of its incorporation into the senior cat assessment. Minimum database diagnostics are discussed, along with recommendations for additional investigative considerations. For example, blood pressure assessment is included as a minimum diagnostic procedure in both apparently healthy and ill cats. Cats age at a much faster rate than humans, so practical timelines for testing frequency are included and suggest an increased frequency of diagnostics with advancing age. The importance of nutrition, as well as senior cat nutritional needs and deficiencies, is considered. Pain is highlighted as its own syndrome, with an emphasis on consideration in every senior cat. The Task Force discusses anesthesia, along with strategies to allow aging cats to be safely anesthetized well into their senior years. The medical concept of quality of life is addressed with the latest information available in veterinary medicine. This includes end of life considerations like palliative and hospice care, as well as recommendations on the establishment of 'budgets of care', which greatly influence what can be done for the individual cat. Acknowledgement is given that each cat owner will be different in this regard; and establishing what is reasonable and practical for the individual owner is important. A discussion on euthanasia offers some recommendations to help the owner make a decision that reflects the best interests of the individual cat.

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.

Reasons for Exclusion of Apparently Healthy Mature Adult and Senior Dogs From a Clinical Trial

Background: Interventional clinical trials intended to maintain health in aging dogs are unusual and require particular attention to exclusion criteria.

Objectives: To describe reasons for exclusion when a mature adult and senior canine population with normal health status was sought.

Animals: Fifty six companion dogs nominated for a randomized controlled trial (RCT).

Procedures: Exclusions occurred within Stage 1 (S1): owner-provided survey information; Stage 2 (S2): medical records review; and Stage 3 (S3): screening examination and within Owner, Dog, or Other factor categories.

Results: Of 56 nominated dogs, 39 were excluded at S1 (n = 19), S2 (n = 5), and S3 (n = 15), respectively. Dogs were excluded for Owner (n = 4), Dog (n = 27), Other (n = 6), and concurrent (Owner + Dog; n = 2) factors. The most common exclusion period was S1 (n = 19), with weight outside the target range being the most common exclusion factor in that stage (n = 10). Heart murmurs were the second most common exclusion factor (S1: n = 1; S3: n = 5); suspected or confirmed systemic illness was third most common (S1: n = 2; S2: n = 3; S3: n = 2). Among dogs who passed S1 and S2 screening (n = 32), 15 dogs (48%) were excluded at S3, for heart murmur > grade II/VI (n = 5), cardiac arrhythmias (n = 2), and clinicopathologic abnormalities (n = 2).

Conclusions and Clinical Relevance: Dogs nominated for a clinical trial for healthy mature adult and senior dogs were excluded for size, previous diagnoses, and newly discovered cardiac abnormalities. For future interventions in mature adult and senior dogs of normal health status, it is important to define expected age-related abnormalities to ensure that meaningful exclusion criteria are used.

Evaluation of the agreement of two oscillometric blood pressure devices with invasive blood pressure in anaesthetized chimpanzees (Pan troglodytes)

OBJECTIVE

To evaluate the agreement of two noninvasive blood pressure devices: a human device with the cuff placed on the wrist (Omron R1) and a veterinary device with the cuff placed on the upper brachium (Surgivet Advisor Vital Signs Monitor) with invasive blood pressure (IBP) measurement in anaesthetized chimpanzees.

STUDY DESIGN

Prospective clinical study.

ANIMALS

A convenience sample of 11 adult chimpanzees undergoing anaesthesia for translocation and routine health checks.

METHODS

Systolic (SAP) and diastolic arterial pressures (DAP) were continuously recorded via a transducer connected to a femoral artery cannula, and at 5 minute intervals from the two oscillometric devices. Agreement was explored using Bland-Altman analysis and bias defined as the mean difference between the two measurement methods. Spearman correlation coefficients were calculated. Significance was set at p < 0.05.

RESULTS

Bias and standard deviation for the Surgivet compared with IBP were 8.6 ± 18 for SAP and 8.4 ± 9.9 for DAP, showing a significant underestimation of both variables. Limits of agreement (LOA) were from -27 to 44 for SAP and from -11 to 28 for DAP. Correlation coefficients between the Surgivet and IBP values were 0.86 for SAP and 0.85 for DAP (p < 0.0001). Bias and standard deviation for the Omron compared with the IBP were -21 ± 25 for SAP and -18 ± 15 for DAP, showing a significant overestimation of both variables. LOA were from -70 to -28 for SAP and from -47 to 11 for DAP. Spearman correlation coefficients between the Omron and IBP values were 0.64 for SAP and 0.72 for DAP (p < 0.0001).

CONCLUSIONS AND CLINICAL RELEVANCE

Although neither device met all the criteria for device validation, the Surgivet presented better agreement with IBP values than the Omron in adult anaesthetized chimpanzees.

Evaluation of the progression of non-azotemic proteinuric chronic kidney disease in dogs

Proteinuria is a recognized risk factor for progression of canine chronic kidney disease (CKD). However, the prognosis of non-azotemic proteinuric CKD in dogs has been studied only to a limited extent. Moreover, the degree to which proteinuria should be decreased to delay CKD progression remains unknown. The purposes of this study were (1) to identify factors associated with disease progression and (2) to investigate the degree of proteinuria, albuminuria, and blood pressure during the course of treatment associated with the progression using time-averaged urine protein:creatinine ratio (UPC) and urine albumin:creatinine ratio (UAC) in canine non-azotemic proteinuric CKD. Twenty-one dogs with non-azotemic proteinuric CKD were included in the study. High UPC and UAC were associated with CKD progression (P < .05). Time-averaged high UPC and UAC were significantly related to progression (P < .05). The cutoff values of these time-averaged parameters for predicting the progression were 4.1 and 2.0, respectively. In dogs with non-azotemic proteinuric CKD, more severe proteinuria and albuminuria were associated with progression. The present study suggests that because UPC ≥ 4.1 and UAC ≥ 2.0 during treatment were associated with a faster progression of non-azotemic proteinuric CKD, therapeutic intervention is warranted.

Acute idiopathic polyradiculoneuritis with secondary arterial hypertension in a 5-year-old male Siberian Husky

Acute canine idiopathic polyradiculoneuritis (ACIP) is one of the most common generalised neuromuscular diseases affecting dogs. In this report, we describe a 5-year-old, 25-kg, male, intact, Siberian Husky dog with ACIP with secondary induced arterial hypertension {systolic blood pressure [mean (m) ± standard deviation (sd)], 214 ± 19 mmHg; mean blood pressure (m ± sd), 164 ± 6.36 mmHg; and diastolic blood pressure (m ± sd), 137 ± 0.7 mmHg} and sinus tachycardia. Heart rate variability analysis indicated decreased vagal activity (low root-mean-square values of successive RR interval differences and percentages of the RR intervals differing by more than 50 ms in the entire recording) and predominance of sympathetic activity. Arterial hypertension was treated with amlodipine but remained greater than the upper limit for 51 days until the dog recovered ambulation. This is the first case report of ACIP and secondary arterial hypertension in a dog. Routine blood pressure measurements should be included in the monitoring of patients with ACIP if arterial hypertension might interfere with patient prognosis.

Influence of clinical setting and cat characteristics on indirectly measured blood pressure and pulse rate in healthy Birman, Norwegian Forest, and Domestic Shorthair cats

BACKGROUND

Measured indirect blood pressure (BP) results in cats in a clinical environment might be affected by stress and characteristics of the cats.

HYPOTHESIS

To investigate the influence of clinical setting, cat characteristics, and life situation on BP and pulse rate (PR) in healthy cats.

ANIMALS

Ninety-four healthy Domestic Shorthair, Birman and Norwegian Forest cats.

METHODS

Blood pressure measured by high-definition oscillometry in 3 settings: cat placed in its own carrier with veterinarian present; cat placed in carrier with owner alone present; and cat placed on table with veterinarian present. Statistical analyses were performed using mixed linear models.

RESULTS

Systolic BP (SBP) did not differ among settings. Higher mean arterial pressure (MAP), diastolic BP (DBP), and PR were found when measurements were performed with cat placed on table, rather than in carrier. Coefficients of variation (CVs) higher for SBP, MAP, DBP, and PR when measured with cat placed on table than in carrier. Birman cats had lower BP than other breeds. Systolic BP, MAP, DBP, and PR increased with age. Cats allowed outdoors had lower PR than cats living strictly indoors.

CONCLUSION AND CLINICAL IMPORTANCE

No difference in SBP was found among settings, but measuring BP with the cat placed on the examination table gave higher MAP, DBP, PR, and CV than measuring BP with the cat in its carrier. Breed affected BP, with lower BP in Birman cats than other breeds. Blood pressure increased with age. Pulse rate was lower in cats allowed outdoors than cats living strictly indoors.

Evaluation of cardioprotective effects of carvedilol in dogs receiving doxorubicin chemotherapy: A prospective, randomized, double-blind, placebo controlled pilot study

The aim of this pilot study was to evaluate the cardioprotective effects of carvedilol in dogs receiving doxorubicin chemotherapy and provide suggestions to future studies based on results and limitations of our study. Thirteen dogs were randomized into two experimental groups: 6 dogs in carvedilol group and 7 dogs in placebo group. In carvedilol group, 0.39 mg/kg ± 0.04 twice-daily oral carvedilol was started on the day of the first doxorubicin treatment and continued throughout the chemotherapy protocol until the final cardiological evaluation. Cardiological evaluations were performed before the first doxorubicin administration and then 10 to 15 days after each subsequent dose. Troponin I and oxidative stress tests were performed with serum collected from dogs at the initial and final cardiological evaluation. Carvedilol produced some echocardiographic and electrocardiographic changes (reduced E velocity and E/IVRT ratio, as well reduced heart rate and increased PR and QT interval) due to its beta-block effect. In placebo group Doppler study showed a significant increase in mitral flow deceleration time (EDT), as well increased amplitude of the S wave in the right, and R wave in the left, precordial chest leads. There were significant difference in the EDT, E/IVRT and A' velocity, as well heart rate, PR interval and R wave in V4/CV6LU precordial chest lead between groups. In conclusion, some indexes of diastolic function and in precordial chest leads were less affected by doxorubicin in carvedilol than in control group. This suggests that carvedilol may have a beneficial effect in canine cancer patients receiving doxorubicin.

Effects of Sedation with Medetomidine and Dexmedetomidine on Doppler Measurements of Ovarian Artery Blood Flow in Bitches

The aim was to evaluate if medetomidine and dexmedetomidine affected arterial ovarian blood flow in dogs. The dogs were randomly assigned to two different groups. In Group 1, medetomidine (10 µg/kg) was administered intramuscularly and, in Group 2, dexmedetomidine (5 µg/kg) was used. After a preliminary exam, arterial blood pressure (BP) was measured and a duplex Doppler ultrasonographic examination of both ovarian arteries was performed. Twenty minutes after the administration of medetomidine or dexmedetomidine, BP and ovarian Doppler ultrasonography were repeated. High quality tracings of ovarian artery flow velocity were obtained in all dogs and Doppler parameters: Peak Systolic Velocity (PSV), End Diastolic Velocity (EDV) and Resistive Index (RI) were measured before and after drug administration in the left (LO) and right (RO) ovaries. PSV and EDV values decreased significantly after drug administration (p < 0.05) compared to the non-sedated values, but no differences were found between the LO and RO (p > 0.05). The RI was not affected by drugs administration in neither of the groups studied (p > 0.05). In conclusion, the administration of medetomidine or dexmedetomidine causes a decrease in blood flow velocity in the ovarian artery and may be a good choice to avoid excessive bleeding prior surgeries in which ovariectomy.

Impact of equipment and handling on systolic blood pressure measurements in conscious dogs in an animal hospital environment

Background

Situational hypertension and differences between devices complicate interpretations of systolic blood pressure (SBP) measurements in dogs.

Hypothesis/Objectives

To evaluate if time point of in‐clinic SBP measurement, type of oscillometric device, and operator affect SBP measurements in conscious dogs.

Animals

Sixty‐seven privately owned dogs with or without chronic kidney disease, divided into 2 study samples (A and B).

Methods

Cross‐sectional diagnostic study. In part A, SBP measurements in dogs were performed using 2 different devices (HDO and petMap) after acclimatization at 3 standardized time points during a clinical visit. In part B, SBP measurements (HDO) were performed in dogs by a trained final year veterinary student and by the owner alone, at the same occasion.

Results

For all dogs, there was no difference in mean SBP (mSBP) among the 3 time points for HDO (P = .12) or petMAP (P = .67). However, intraindividual mSBP differences of up to 60 mm Hg between time points were documented. Mean SBP obtained with petMAP was on average 14 (95% CI: 8‐20) mm Hg higher than mSBP obtained with HDO, and this difference increased with increasing SBP. Mean SBP measurements obtained by the trained student were 7 (95% CI: 2‐11) mm Hg higher than mSBP measurements obtained by the owner.

Conclusions and Clinical Importance

According to the results of this study, time point of in‐clinic SBP measurement in dogs is of minor importance, and instructing owners to perform measurements might reduce suspected situational hypertension. Differences in mSBP measured with HDO and petMAP underscore the need for validation of BP devices used clinically.

Anestesia intravenosa contínua com cetamina racêmica ou dextrocetamina e detomidina em cadelas

RESUMO Objetivou-se com este estudo comparar a associação de detomidina e cetamina ou dextrocetamina, por via intravenosa contínua, em oito cadelas submetidas a dois protocolos: GCD - indução anestésica com 5mg/kg e infusão intravenosa contínua de 20mg/kg/h de cetamina; e GDD - indução com 3,5mg/kg e infusão de 14mg/kg/h de dextrocetamina. Associou-se detomidina, 30µg/kg/h, em ambos os grupos. Registraram-se frequência cardíaca (FC), pressão arterial (PA), frequência respiratória (f), temperatura (TC), miorrelaxamento, analgesia, hemogasometria e eletrocardiograma, antes e 15 minutos após a MPA (Mbasal e Mmpa); após o início da infusão (Mic); a cada 10 minutos até 90 minutos (M10, M20, M30, M40, M50, M60, M70, M80 e M90); e 30 minutos após o fim da infusão (M120). Foi observada bradicardia em Mmpa no GCD e de Mmpa a M10 no GDD. Ocorreu hipotensão em Mmpa e hipertensão a partir de Mic. A f diminuiu de M10 a M30. Foram observados: onda T de alta amplitude, bloqueios atrioventriculares e parada sinusal. Ocorreu acidose respiratória. O período de recuperação foi de 219,6±72,3 minutos no GCD e de 234,1±96,8 minutos no GDD. A cetamina e a dextrocetamina, associadas à detomidina por infusão contínua, causam efeitos cardiorrespiratórios e anestésicos similares.