Ultrasonographic measurement of caudal vena cava to aorta ratio during fluid resuscitation of dogs with spontaneous circulatory shock.

OBJECTIVES: To describe the change in the caudal vena cava to aorta ratio (CVC:Ao) ratio during fluid resuscitation of circulatory shock in dogs and compare these results with those of the physical examination and blood lactate. MATERIALS AND METHODS: Perfusion parameters and blood lactate were recorded at admission. An abdominal point-of-care ultrasound protocol was performed, during which the caudal vena cava to aorta ratio was measured on the spleno-renal view. Measurements were performed within 5 minutes before and after a 10 mL/kg crystalloid fluid bolus. Investigators were not blinded to therapeutic interventions. RESULTS: Twenty-nine dogs with physical signs of circulatory shock were enrolled. Caudal vena cava to aorta ratios were below reference interval in 28 of 29 dogs. After bolus administration, median caudal vena cava diameter increased by 0.14 cm (0.69 to 0.83 cm) and median aorta diameter increased by 0.03 cm (0.87 to 0.90 cm) and caudal vena cava to aorta ratio returned to within reference range in 65% of dogs (13/29). Bolus administration was associated with an increase in median caudal vena cava to aorta ratio of 0.10 (95% CI:0.05 to 0.16, P=0.0005). Blood lactate did not change significantly. Heart rate and capillary refill time decreased significantly after fluid bolus (heart rate: estimate=-19 bpm, 95% CI:-30 to -8, P=0.002; capillary refill time: estimate=-1.0 s, 95% CI:-1.3 to -0.7, P < 0.0001). CLINICAL SIGNIFICANCE: In this population of dogs with circulatory shock, the caudal vena cava to aorta ratio significantly increased after a fluid bolus. Future studies that implement blinding of the outcome assessors are warranted to confirm these findings.

Impact of flow and temperature on non-dyspnoeic dogs' tolerance undergoing high-flow oxygen therapy.

OBJECTIVES: To prospectively describe the impact of gas flow rate and temperature on dog's tolerance of high-flow nasal oxygen therapy during recovery from anaesthesia, hypothesizing that higher flow rates and temperatures will decrease tolerance. MATERIALS AND METHODS: Twelve non-dyspnoeic client-owned dogs recovering from general anaesthesia were included in this study. After extubation, a nasal cannula was positioned and high-flow nasal oxygen therapy was initiated. Two flow rates (two or four time the theoretical minute ventilation: HF2 and HF4), each of them combined with two temperatures (31 and 37°C: T31 and T37), were randomly applied (four conditions per dog). For each condition, cardiovascular and respiratory parameters (heart rate, respiratory rate, systolic arterial blood pressure and pulse oximeter oxygen saturation), sedation score and tolerance score were recorded at initiation (T0 ) and after 10 minutes of accommodation (T10 ). RESULTS: Sedation scores were not significantly different between the four conditions. Cardiovascular and respiratory parameters were not significantly different between any condition at both T0 and T10 . Tolerance scores were good and not significantly different between any flow rate or temperature (HF2-T31: 4 (2-4), HF4-T31: 4 (2-4), HF2-T37: 4 (2-4), HF4-T37: 4 (1-4)). CLINICAL SIGNIFICANCE: The gas flow rates and temperatures studied have no impact on tolerance during the recovery period of non-dyspnoeic dogs, and high-flow nasal cannula is well tolerated. Further studies are required to confirm these results in dyspnoeic dogs.

Prospective pilot study for evaluation of high-flow oxygen therapy in dyspnoeic dogs: the HOT-DOG study.

OBJECTIVES: To describe the use, effectiveness and tolerance of high-flow oxygen therapy in dyspnoeic dogs. MATERIALS AND METHODS: Prospectively, dogs in acute respiratory distress admitted to an intensive care unit between January and May 2018 that failed to respond to nasal oxygen therapy and medical stabilisation after 30 minutes were transitioned to high-flow oxygen therapy. High-flow oxygen therapy, delivered an inspired oxygen fraction of 100% using an air/oxygen blender, active humidifier, single warmed tube and specific nasal cannula. Respiratory rate, pulse oximetry (SpO2 ), heart rate and a tolerance score were assessed every 15 minutes from T0 (under nasal oxygen) to 1 hour (T60 ), and PaO2 and PaCO2 at T0 and T60 . Complications were recorded for each dog. RESULTS: Eleven dogs were included. At T60 , PaO2 , flow rate and SpO2 were significantly greater than at T0 (171 ± 123 versus 73 ± 24 mmHg; P=0.015; 18 ±12 L/minute versus 3.2 ± 2.0 L/minute, P<0.01; 97.7 ±2.3% versus 91.6 ±7.2%, P=0.03, respectively). There was no significant difference in PaCO2 , respiratory rate or heart rate between T0 and T60 . Tolerance was excellent, and there were no complications. CLINICAL SIGNIFICANCE: High-flow oxygen therapy improves markers of oxygenation in dyspnoeic dogs and is an effective means to deliver oxygen with comfort and minimal complications.

Sonographic assessment of volaemia: development and validation of a new method in dogs.

OBJECTIVES: The aims of this study were to describe a method for the sonographic assessment of volaemia, to determinate inter- and intra-operator variability and to assess the ability to detect blood loss after blood donation in healthy dogs. MATERIALS AND METHODS: The left kidney was identified in a spleno-renal view, and transverse views of the caudal vena cava and aorta were obtained in 12 dogs. Vessel diameters were measured in B-mode, in duplicate by two operators, and the caudal vena cava:aorta ratio was calculated. Intra- and inter-operator variabilities were assessed using a Bland-Altman method by plotting the differences between the repeated measurements obtained from the same subject by the same operator and by the two operators against their means. Before and after blood donation measurements were compared using paired t-tests or one-sample t-tests, if appropriate. RESULTS: Intra- and inter-operator variability was within the limit of agreement for the vast majority of measurements. After a blood donation of 9·8 ±2·2 mL/kg, the mean aorta measurements were not significantly different from those obtained before blood donation (1·11 versus 1·10, P=0·28), whereas the mean caudal vena cava measurements and caudal vena cava:aorta ratios were significantly lower (1·28 versus 1·01, P<0·0001; 1·17 versus 1·01, P=0·0001, respectively). CLINICAL SIGNIFICANCE: The low intra- and inter-operator variabilities in the caudal vena cava, aorta and caudal vena cava:aorta ratio measurements support their reliability and operator independency. The sonographic assessment of volaemia appears to be a promising non-invasive, repeatable point-of-care ultrasound protocol for assessment and monitoring of blood loss. Further studies are needed to assess the sonographic assessment of volaemia protocol in spontaneously bleeding dogs.

Effects of buprenorphine in the adrenal, thyroid, and cytokine intra-operative responses in a rat model (Rattus norvegicus): a preliminary study.

OBJECTIVES: Buprenorphine is a common analgesic in experimental research, due to effectiveness and having few side-effects, including a limited influence in the immune and endocrine systems. However, how buprenorphine affects cytokine levels and the adrenal and thyroid response during general anesthesia and surgery is incompletely understood. This study aimed to assess whether buprenorphine modulated significantly those responses in rats submitted to general anesthesia, mechanical ventilation, and surgical insertion of intravascular catheters. MATERIALS AND METHODS: Animals were anesthetized with isoflurane, mechanically ventilated, and surgically instrumented for carotid artery and the femoral vein catheter placement. The test group (n=16), received buprenorphine subcutaneously before surgery, whereas the control group (n=16) received normal saline. Blood sampling to determine plasma levels of adrenocorticotropic hormone (ACTH), corticosterone (CS), total thyroxine (TT4), total triiodothyronine (TT3), thyroid-stimulating hormone (TSH), TNF-α, IL6, IL10, TNF-α, IL6, and IL10 mRNA was performed at 10 min after completion of all surgical procedures and at 90, 150, 240, and 300 min thereafter, with the animals still anesthetized and with mechanical ventilation. RESULTS: Buprenorphine-treated animals had higher levels of ACTH, CS, and TT4 at several time points (P<0.05) and TSH and TT3 at all-time points (P<0.05). They also had increased IL10, TNF-α, and IL10 mRNA levels. CONCLUSION: In this model, buprenorphine significantly modulated the intra-operative cytokine and endocrine response to anesthesia, mechanical ventilation, and surgical placement of intravascular catheters. The mechanism and significance of these findings remain undetermined. Researchers should be aware of these effects when considering the use of buprenorphine for analgesic purposes.

Pre- and Post-Transfusion Alloimmunization in Dogs Characterized by 2 Antiglobulin-Enhanced Cross-match Tests.

BACKGROUND: When dogs are transfused, blood compatibility testing varies widely but may include dog erythrocyte antigen (DEA) 1 typing and rarely cross-matching. OBJECTIVES: Prospective study to examine naturally occurring alloantibodies against red blood cells (RBCs) and alloimmunization by transfusion using 2 antiglobulin-enhanced cross-match tests. ANIMALS: Eighty client-owned anemic, 72 donor, and 7 control dogs. METHODS: All dogs were typed for DEA 1 and some also for DEA 4 and DEA 7. Major cross-match tests with canine antiglobulin-enhanced immunochromatographic strip and gel columns were performed 26-129 days post-transfusion (median, 39 days); some dogs had an additional early evaluation 11-22 days post-transfusion (median, 16 days). Plasma from alloimmunized recipients was cross-matched against RBCs from 34 donor and control dogs. RESULTS: The 2 cross-match methods gave entirely concordant results. All 126 pretransfusion cross-match results for the 80 anemic recipients were compatible, but 54 dogs died or were lost to follow up. Among the 26 recipients with follow-up, 1 dog accidently received DEA 1-mismatched blood and became cross-match-incompatible post-transfusion. Eleven of the 25 DEA 1-matched recipients (44%) became incompatible against other RBC antigens. No naturally occurring anti-DEA 7 alloantibodies were detected in DEA 7- dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The antiglobulin-enhanced immunochromatographic strip cross-match and laboratory gel column techniques identified no naturally occurring alloantibodies against RBC antigens, but a high degree of post-transfusion alloimmunization in dogs. Cross-matching is warranted in any dog that has been previously transfused independent of initial DEA 1 typing and cross-matching results before the first transfusion event.

Implication, clinical and biological impact of vector-borne haemopathogens in anaemic dogs in France: a prospective study.

OBJECTIVES: To prospectively describe the clinical and biological impact of vector-borne haemopathogens in anaemic dogs in France and occurrence of haemolysis. MATERIALS AND METHODS: This prospective descriptive cohort study includes 134 client-owned dogs that were anaemic on admission at the Veterinary Teaching Hospital of VetAgro Sup, Lyon, France. They underwent comprehensive screening with PCR to detect a panel of vector-borne haemopathogens, SNAP Leishmania and SNAP 4Dx Plus (IDEXX). RESULTS: Vector-borne haemopathogen-associated anaemia accounted for 17·2% (23/134) of anaemic cases. PCR for Babesia species, Mycoplasma species, Anaplasma platys or Ehrlichia canis and positive serology for Leishmania species, occurred in 11/23, 10/23, 2/23, 1/23 and 1/23 cases, respectively. Two dogs had positive PCR for both Babesia and Mycoplasma species. All dogs infected with Mycoplasma species alone had neoplastic disease. Vector-borne haemopathogens were the second most common cause of haemolysis (7/23, 30·4%). In the multivariable regression model, males were overrepresented ( OR : 2·82, P=0·03) and haemolysis ( OR : 3·31, P=0·01) was more frequent in dogs with vector-born haemopathogen-associated anaemia. CLINICAL SIGNIFICANCE: Vector-borne haemopathogens are a common cause of anaemia in this geographical region.

Hemorrhagic, Hemostatic, and Thromboelastometric Disorders in 35 Dogs with a Clinical Diagnosis of Leptospirosis: A Prospective Study.

BACKGROUND: Leptospirosis in dogs is occasionally associated with a hemorrhagic syndrome, the pathophysiology of which is not fully understood. HYPOTHESIS/OBJECTIVES: To characterize hematologic, hemostatic, and thromboelastometric abnormalities in dogs with leptospirosis and to study their association with hemorrhagic diatheses and outcomes. ANIMALS: Thirty-five client-owned dogs. METHODS: A prospective observational single cohort study was conducted. Results from the CBC, coagulation tests (prothrombin, activated partial thromboplastin and thrombin times, fibrinogen, fibrin(ogen) degradation products, and D-dimer concentrations), rotational thromboelastometry (TEM), signalment, hemorrhagic diatheses, occurrence of disseminated intravascular coagulation (DIC) at admission, and survival to discharge were recorded. RESULTS: The most common hematologic and hemostatic abnormalities were anemia (30/35), thrombocytopenia (21/35), and hyperfibrinogenemia (15/35). Eight dogs were diagnosed with DIC. A normal TEM profile was found in 14 dogs, a hypercoagulable profile in 14 dogs, and a hypocoagulable profile in 7 dogs. The 8 dogs with hemorrhagic diatheses at admission had significantly decreased platelet counts (P = .037) and increased D-dimer concentrations (P = .015) compared with other dogs. Dogs with a hypocoagulable profile exhibited more hemorrhagic diatheses compared with the dogs that had normal and hypercoagulable profiles (P = .049). The mortality rate was lower in dogs with a hypercoagulable profile than in those with a hypocoagulable profile (21% vs 57%; P = .043). Disseminated intravascular coagulation was not a significant prognostic factor. CONCLUSIONS AND CLINICAL IMPORTANCE: Thromboelastometric parameters were altered in dogs with both hypercoagulable and hypocoagulable profiles. A hypocoagulable profile was significantly correlated with hemorrhagic diathesis and higher mortality rate.

Thoracic bite trauma in dogs and cats: a retrospective study of 65 cases.

OBJECTIVES: To report a case series of thoracic bite trauma in dogs and cats and to evaluate risk factors for mortality. METHODS: A retrospective study concerning thoracic bite wounds in dogs and cats was performed. Lesions were categorized by depth of penetration: no wound, superficial, deep or penetrating. Thoracic radiographic reports were reviewed. Lesion management was classified as non-surgical, wound exploration, or explorative thoracotomy. RESULTS: Sixty-five cases were collected. Twenty-two percent of patients with normal respiratory patterns showed thoracic radiographic lesions. Respiratory distress was not correlated with mortality. Twenty-eight patients were presented with superficial wounds and 13 with deep wounds. Eight patients exhibited penetrating wounds. Radiographic lesions were observed in 77% of dogs and 100% of cats. Explorative thoracotomy was performed in 28% of patients, and surgical wound exploration in 17.2%. With the exception of skin wounds, thoracic wall discontinuity was the most frequent lesion. Thoracotomy was associated with increased length of hospitalisation but was not correlated with mortality. The mortality rate was 15.4%. No studied factor correlated with mortality, and the long-term outcomes were excellent. CLINICAL SIGNIFICANCE: A penetrating injury, more than three radiographic lesions, or both together seemed to be indicative of the need for a thoracotomy. In the absence of these criteria, systematic bite wound explorative surgery is recommended, with extension to thoracotomy if thoracic body wall disruption is observed.

Differences between coagulation and cytokine profiles in dogs of different ages.

In human medicine, age is a risk factor for thromboembolic diseases associated with hypercoagulable and antifibrinolytic states, but information in veterinary medicine is limited. This study compared the thromboelastometric (TEM) profiles of two groups of dogs of distinct ages. Ten healthy old (>10 years) Beagles and 10 healthy young (<3 years) Beagles were recruited. White blood cell counts and haematocrit were significantly lower in the old group compared to the young group, and fibrinogen, total proteins, globulins and monocyte chemoattractant protein-1 plasma concentrations were significantly higher in the old group. Comparisons of the TEM profiles indicated a hypercoagulable profile and a decrease in fibrinolytic activity in all old Beagles. The findings support the need to consider age as a possible risk factor for thrombosis in dogs.

Renal haemodynamic response to amino acids infusion in an experimental porcine model of septic shock.

BACKGROUND: Acute kidney injury (AKI) is common in sepsis. Treatments allowing maintenance of renal blood flow (RBF) could help to prevent AKI associated with renal hypoperfusion. Amino acids (AA) have been associated with an increase of RBF and glomerular filtration rate (GFR) in several species. The aim of this study was to evaluate the effects of an AA infusion on RBF and GFR in a porcine model of septic shock. METHODS: A total of 17 piglets were randomly assigned into three groups: Sham (Sham, n = 5), sepsis without AA (S-NAA, n = 6), sepsis treated with AA (S-AA, n = 6). Piglets preparation included the placement of ultrasonic transit time flow probes around left renal artery for continuous RBF measurement; ureteral catheters for GFR and urine output evaluation; pulmonary artery catheter for cardiac output (CO) and pulmonary arterial pressure measurements. Mean arterial pressure (MAP) and renal vascular resistance (RVR) were also determined. Septic shock was induced with a live Pseudomonas aeruginosa infusion. Crystalloids, colloids and epinephrine infusion were used to maintain and restore MAP > 60 mmHg and CO > 80% from baseline. RESULTS: Renal haemodynamic did not change significantly in the Sham group, whereas RBF increased slightly in the S-NAA group. Conversely, a significant increase in RVR and a decrease in RBF and GFR were observed in the S-AA group. AA infusion was associated with a higher requirement of epinephrine [340.0 (141.2; 542.5) mg vs. 32.5 (3.8; 65.0) mg in the S-NAA group P = 0.044]. CONCLUSION: An infusion of amino acids impaired renal haemodynamics in this experimental model of septic shock.

Bilothorax following cholecystectomy in a dog.

A 10-year-old, entire female Pyrenean shepherd dog was presented for acute onset of gastroenteritis. An abdominal ultrasound examination showed the presence of a suspected gall bladder mucocele. After surgery for cholecystectomy, the dog showed signs of an acute onset of respiratory distress due to bilothorax. The bilothorax responded well to medical treatment that comprised of thoracocentesis and oral steroids.

Investigation of the role of aldosterone in hypertension associated with spontaneous pituitary-dependent hyperadrenocorticism in dogs.

The aim of this study was to evaluate the role of aldosterone as an initiating and/or perpetuating factor in hypertension associated with pituitary-dependent hyperadrenocorticism (PDH) in dogs. Thirteen dogs with PDH and 11 healthy control dogs were used. In all dogs, arterial blood pressure and plasma sodium, potassium, basal aldosterone, post-ACTH aldosterone, basal cortisol and post-ACTH cortisol concentrations were measured. The tests were repeated 10 days and three months after the beginning of o,p'-DDD treatment in PDH dogs. In untreated PDH dogs, plasma aldosterone was significantly decreased, whereas cortisol, sodium and arterial blood pressure were significantly increased compared to healthy dogs. Hypertension remained in most treated PDH dogs despite normalisation of cortisol and persistently low aldosterone levels. These results did not demonstrate that aldosterone is involved in the development and perpetuation of hypertension in PDH. However, glucocorticoids seemed to play a major role as an initiating and perpetuating factor in PDH in dogs.

Canine T-cell lymphomas: a morphological, immunological, and clinical study of 46 new cases.

The aim of this study is to report 46 new cases of canine T-cell lymphomas among a series of 140 lymphomas studied by immunophenotyping (incidence 32.8%). According to the updated Kiel classification adapted to the canine species, 13 were classified as low-grade and 33 as high-grade lymphomas. Among the low-grade lymphomas, five were small clear-cell lymphomas, three were pleomorphic small-cell lymphomas, and five mycosis fungoides. Among the high-grade cases, there were 11 pleomorphic mixed-, small-, and large-cell lymphomas, 6 pleomorphic large-cell lymphomas, 11 lymphoblastic lymphomas, and 5 unclassifiable high-grade plasmacytoid lymphomas. The cytohistologic features were highly suggestive of a T-cell phenotype on the basis of cell morphology (irregular nuclei and clear cytoplasms) (30/46 cases), a T-cell zone pattern, and the presence of hyperplastic postcapillary venules (22/46 cases). All 46 cases were CD3+ CD79a-, and among 34 cases investigated for CD4 and CD8 expression, 13 were CD4+CD8-, 13 were CD8+CD4-, and 8 were CD4CD8 double positive or double negative. The pleomorphic mixed lymphomas were mainly CD4+CD8- (6/7) and the lymphoblastic lymphomas were double positive or double negative (6/8). The main clinical, hematologic, and biochemical features were generalized (28/46) or regional lymphadenopathy (16/46), hepatosplenomegaly (15/46), extranodal involvement (11/46), mediastinal mass (9/46), and leukemia (8/46), which were mainly present in cases of lymphoblastic lymphomas and hypercalcemia (16/46).

Atypical forms of canine leishmaniosis.

Canine leishmaniosis is a common disease in the Mediterranean area, but sporadic cases in dogs having travelled through endemic regions are also reported. The disease's evolution is usually chronic and symptoms are either non-specific (fever, weight loss, lethargy, enlarged lymph nodes), dermatological, renal or ocular. The purpose of this article is to review the literature and to describe our own experience of certain atypical forms of canine leishmaniosis. These include specific skin lesions, monoclonal gammopathy, renal failure (without any other signs), chronic colitis, haemostatic problems and disorders of the cardiovascular, respiratory and musculo-skeletal systems.