USE OF VISCOELASTIC COAGULATION TESTING IN MEGACHIROPTERA (PTEROPUS HYPOMELANUS AND PTEROPUS VAMPYRUS) REVEALS HIGH VARIABILITY IN CLOT KINETICS.

Megachiroptera is a mammalian suborder that includes old world fruit bats. Common clinical problems among captive Megachiroptera, such as liver disease (e.g., iron storage disease), kidney disease (e.g., protein-losing nephropathy), and heart disease (e.g., dilated cardiomyopathy), carry elevated risk for hemostatic derangements. The assessment of viscoelastic coagulation assays, however, has not yet been reported in bats. The main objective of the study was to describe viscoelastography data using the Viscoelastic Coagulation Monitor (VCM) Vet in captive large flying foxes (Pteropus vampyrus) (n = 20) and variable flying foxes (Pteropus hypomelanus) (n = 10). Additional objectives were to compare viscoelastic and clotting parameters (1) between healthy P. vampyrus and P. hypomelanus bats and (2) between untreated bats and those treated with meloxicam or aspirin, and (3) to examine relationships between activated partial thromboplastin time (aPTT) and potentially homologous viscoelastic parameters clotting time (CT) and clot formation time (CFT). The results showed marked variability among clinically normal bats. The intrinsic pathway, as measured by aPTT, had prolonged times compared with most terrestrial mammals, but similar times to birds, marine mammals, and sea turtles. A search of P. vampyrus genome found stop codons present in two exons of the factor XI gene; alterations in factor XI expression would be expected to alter intrinsic coagulation. Because of the high variability, no statistically significant findings were noted in the secondary objectives. Correlation between aPTT and CT or CFT was not strong (rs = 0.406 or 0.192, respectively). The results from this study suggest that clot kinetics vary widely among Megachiroptera when using the VCM Vet with untreated blood. A prolonged intrinsic coagulation pathway, as has been found in other megachiropteran species, and activation of the extrinsic coagulation pathway during venipuncture may be responsible for the inconsistent results.

Outcomes of 434 dogs with non-steroidal anti-inflammatory drug toxicosis treated with fluid therapy, lipid emulsion, or therapeutic plasma exchange.

BACKGROUND: Traditional management of non-steroidal anti-inflammatory drug (NSAID) intoxication includes gastrointestinal decontamination, intravenous administration of fluids (IVF), and gastroprotection. Intravenous administration of lipid emulsion (ILE) and therapeutic plasma exchange (TPE) are popular novel therapeutic strategies. HYPOTHESIS: Compare outcomes of dogs treated with IVF, ILE, and TPE for NSAID intoxications and evaluate outcome predictors for drug subgroups. ANIMALS: Four hundred thirty-four dogs with NSAID intoxications (2015-2020). METHODS: Multicenter retrospective study of ibuprofen, carprofen, and naproxen intoxication. An ordinal outcome was defined as mild gastrointestinal, moderate kidney, or signs of severe central nervous system disease. RESULTS: Signs of neurological disease were overrepresented and acute kidney injury underrepresented in the TPE group among dogs exposed to kidney- or CNS-toxic doses (P = .05), though all TPE dogs with signs of neurological disease had evidence of neurotoxicity at presentation. Dogs treated with IVF had a higher maximal creatinine concentration (median, 1.1 mg/dL; range, 0.4-8.44 mg/dL) compared with IVF + ILE (median, 0.9 mg/dL; range, 0.4-6.2 mg/dL; P = .01). Increased maximum time to presentation (P < .001), higher baseline creatinine (P < .001) and PCV (P = .007), and absence of induced emesis (P < .001) were associated with greater clinical severity. Ibuprofen toxicosis was associated with more severe clinical signs compared with carprofen (P = .03). Overall survival rate was 99%. CONCLUSIONS AND CLINICAL IMPORTANCE: NSAID toxicosis generally carries an excellent prognosis in dogs. Despite similar outcomes of lower incidence of AKI in the TPE group, and slightly lower maximal creatinine concentration in dogs treated with ILE vs IVF alone, ILE and TPE should be considered in the management of severe NSAID toxicosis.

Outcomes of nonsteroidal anti-inflammatory drug toxicosis treated with therapeutic plasma exchange in 62 dogs.

BACKGROUND: Therapeutic plasma exchange (TPE) is gaining popularity for the management of nonsteroidal anti-inflammatory drug (NSAID) overdose in dogs. HYPOTHESIS/OBJECTIVES: Describe a population of dogs treated with TPE for NSAID overdose. ANIMALS: Sixty-two dogs with NSAID overdose treated with TPE. METHODS: Multicenter retrospective study of dogs treated with TPE for ibuprofen, carprofen, or naproxen overdose. RESULTS: The median dose of ibuprofen, carprofen or naproxen ingested was 533 mg/kg (range, 36-4857 mg/kg), 217 mg/kg (range, 88-625 mg/kg) and 138 mg/kg (range, 26-3000 mg/kg), respectively. Based on previously established toxic ranges for each NSAID, 2 (3.2%), 14 (22.6%), and 46 (74.2%) dogs ingested a gastrointestinal, renal, and neurological toxic dose, respectively. The median time between ingestion and presentation was 4 hours (range, 1-20 hours). The median number of plasma volumes processed was 1.6 (range, 0.4-2.2). The median TPE session duration was 2 hours (range, 1-4.5 hours). Circuit clotting developed during 8 (12.9%) sessions. Patient adverse events reported during 21 (33.8%) sessions consisted of urticaria (12.9%), asymptomatic hypocalcemia (9.6%), and hypotension (9.6%). The median duration of hospitalization was 2.25 days (range, 1-11 days). Sixty-one (98.4%) dogs survived to discharge, and none were rehospitalized. Thirty-one (91.1%) of the 34 dogs with at least 1 follow-up visit were not azotemic at the time of reevaluation. CONCLUSIONS AND CLINICAL IMPORTANCE: This population of dogs managed with TPE had excellent outcomes, even in cases of high NSAID dose ingestion. When TPE is available and the time frame is appropriate, this extracorporeal modality should be considered for the management of NSAID overdose.

Retrospective evaluation of the use of quick Sepsis-related Organ Failure Assessment (qSOFA) as predictor of mortality and length of hospitalization in dogs with pyometra (2013-2019): 52 cases.

OBJECTIVE: To evaluate the prognostic utility of quick Sepsis-related Organ Failure Assessment (qSOFA) for prediction of in-hospital mortality and length of hospitalization in dogs with pyometra. DESIGN: Retrospective cohort study from February 2013 to April 2019 SETTING: Tertiary referral hospital ANIMALS: Fifty-two dogs referred with confirmed diagnosis of pyometra INTERVENTIONS: None MEASUREMENTS AND PRINCIPAL OUTCOMES: Sixty-five percent of dogs survived to discharge. A cut-off score of ≥2 for qSOFA was associated with in-hospital mortality (odds ratio 6.51 [95% CI: 1.35 - 31.3]) P = 0.019. The area under the receiver operator characteristic curve for a qSOFA score ≥ 2 for mortality was 0.72 (95% CI: 0.59-0.85), with a sensitivity of 77.8% and a specificity of 66.7%. The mean ± SD number of organs with dysfunction was significantly higher in dogs with a qSOFA score ≥2 1.76 ± 0.83 compared to dogs with a qSOFA score < 2 1.08 ± 1.09, P = 0.015. The presence of a qSOFA score ≥ 2 was associated with a longer time of hospitalization in survivors with a median (interquartile range) length of stay in qSOFA < 2 (48 [33]) hours versus qSOFA score ≥ 2 (78 [52]) hours, P = 0.027. CONCLUSIONS: In dogs with pyometra, the qSOFA score was associated with mortality and length of hospitalization. This score might be useful to improve the risk stratification in dogs with pyometra. Further studies are necessary to evaluate the predictive capacity of qSOFA in other septic patient populations.

Extracorporeal blood purification in acutely intoxicated veterinary patients: A multicenter retrospective study (2011-2018): 54 cases.

OBJECTIVE: To investigate the clinical outcome and complications associated with extracorporeal blood purification (EBP) using either hemodialysis (HD), hemodialysis and hemoperfusion (HD + HP), or therapeutic plasma exchange (TPE) for the management of acute toxin ingestion in small animals. DESIGN: Retrospective, multicenter study from January 2011 to July 2018. SETTING: One university teaching hospital and one private specialty hospital. ANIMALS: Fifty-one dogs and 3 cats with a history of acute toxin exposure that could lead to severe morbidity and mortality, managed with different EBP techniques. MAIN RESULTS: Nonsteroidal anti-inflammatory drugs (38/54, 52%), baclofen (8/54, 15%), and ethylene glycol (7/54, 13%) were the most common toxicities treated with EBP. Membrane-based TPE was used most commonly (22/54, 40.7%), followed by HD (17/54, 31.5%) and then HD + HP (15/54, 27.8%). There was an 83.3% (45/54) overall survival, with 88.9% (8/9) of nonsurvivors having clinical signs prior to therapy. One third (18/54) of the patients never developed clinical signs of toxicity. Treatment complications occurred in 44.4% (24/54) of the animals, although only 18.5% (10/54) of these complications, such as mild hypotension, thrombocytopenia secondary to the HP cartridge, facial swelling after plasma transfusion for TPE, bleeding from catheter size secondary to heparinization, or clotting of the system, could be attributed to the EBP treatment. None of the nonsurvivors died because of EBP complications. CONCLUSIONS: Early initiation of EBP therapy might be considered as an alternative route of decontamination in severe acute toxicities with high potential for significant morbidity and mortality. The survival rate in small animals undergoing EBP is high despite exposure to potential lethal doses of toxins, and survival appears to be more likely if clinical signs of toxicity are not present at the time of EBP. Continued research is warranted with randomized controlled clinical trials to further evaluate the clinical efficacy and benefit of EBP.

Management of severe baclofen toxicosis using hemodialysis in conjunction with mechanical ventilation in a cat with chronic kidney disease.

CASE SUMMARY: A 2-year-old castrated male domestic shorthair cat was presented for evaluation of acute and progressive neurologic signs 2-4 h after exposure to baclofen. The suspected ingested dose was 2.1 mg/kg. On admission, the cat was tetraplegic with stuporous mentation, and venous blood gas analysis showed mild hypercapnia (PvCO2 43.4 mmHg) raising concern for hypoventilation. Owing to the acute nature of the ingestion, severity of the clinical signs and reported history of chronic kidney disease, hemodialysis was recommended to remove the toxin. A 5 h hemodialysis session was performed using an intermittent platform without hemoperfusion. At the beginning of hemodialysis, worsening hypoventilation and hypercapnia (PvCO2 88.6 mmHg) required endotracheal intubation and manual ventilation initially, followed by mechanical ventilation. At the end of the dialysis session, the cat was breathing spontaneously and disconnected from the ventilator. The cat was ambulatory and alert 1 h after the end of dialysis. After an additional 12 h of monitoring, the cat had full return of neurologic function and was discharged from hospital. Serum baclofen concentration measured prior to, during and after hemodialysis showed a 77.7% reduction in baclofen levels immediately after hemodialysis. RELEVANCE AND NOVEL INFORMATION: This is the first report of baclofen toxicity in a cat successfully treated with hemodialysis and mechanical ventilation simultaneously. Treatment with hemodialysis therapy and mechanical ventilation could be considered in cases of acute baclofen toxicosis to improve outcome and reduce the length of the hospital stay.

Successful resolution of urothorax secondary to non-traumatic uroabdomen in a cat managed with peritoneal dialysis as a bridge to surgery.

CASE SUMMARY: A 9-year-old neutered male domestic shorthair cat was presented for evaluation of severe hemodynamic collapse and suspected lower urinary tract disease. On admission, severe metabolic acidosis, hyperkalemia and azotemia, and electrocardiographic findings consistent with cardiotoxicity were identified. The diagnosis of uroabdomen was made based on abdominal fluid to plasma concentration ratios of creatinine and potassium. A central line catheter was placed percutaneously into the abdomen for peritoneal drainage and used for peritoneal dialysis as a bridge to surgery. Retrograde contrast cystography confirmed rupture of the urinary bladder. Point-of-care ultrasound of the chest postoperatively revealed the presence of mild pleural effusion. Echocardiography was then performed showing no evidence of cardiac disease. Pleural fluid analysis revealed a transudate with a creatinine ratio of 2.38 ([Creatinine]pleural fluid/[Creatinine]plasma), consistent with the diagnosis of urothorax. The cat recovered uneventfully from surgery and was monitored for signs of respiratory distress during the rest of its stay in hospital. The cat was discharged 4 days later and the pleural effusion resolved without further medical intervention. RELEVANCE AND NOVEL INFORMATION: There is limited information on the causes of urothorax and uroabdomen management of feline patients. Pleural effusion is a complication observed in critically ill cats secondary to fluid overload, underlying cardiomyopathy, primary thoracic pathology or a combination of these. To our knowledge, this is the first report of urothorax in a cat secondary to non-traumatic uroabdomen. Careful monitoring of respiratory signs consistent with pleural space disease is recommended in cases of uroabdomen.

Rapid Patient-Side Evaluation of Endothelial Glycocalyx Thickness in Healthy Sedated Cats Using GlycoCheck® Software.

The endothelial glycocalyx (EG) determines transvascular fluid fluxes, and influences inflammation, coagulation, and capillary blood flow. The GlycoCheck® software calculates EG thickness using sidestream dark field videomicroscopy recordings. This method has not been evaluated for use in cats. The aim of the present study was to evaluate the use of GlycoCheck® for estimating EG thickness in healthy cats, and to investigate the variability of EG thickness in this population. One hundred and one healthy research-purposed cats were included in the study. The cats were sedated, and a handheld videomicroscope, connected to GlycoCheck® software, was used to evaluate the sublingual microvasculature. The parameters measured included perfused boundary region (PBR, an indirect measurement of EG thickness) in vessels between 5 and 25 µm in diameter, valid vessel density, percentage red blood cell filling, and median red blood cell column width. Heart rate, respiratory rate, pulse oximetry and oscillometric blood pressure readings were also recorded. There were 35 neutered male cats, 11 intact males, 38 neutered females, and 17 intact females. The average age was 63 months (range, 11-160 months). Tolerance intervals for PBR (vessel diameter 5-25 µm) were 1.89-3.00 µm (95% CI, lower limit 1.76-2.04, upper limit 2.83-3.13 µm); for valid vessel density were 73.33-333.33 µm/mm2 (95% CI, lower limit 77.00-99.33, upper limit 312.67-350.33 µm/mm2); for percentage red blood cell filling were 59.85-85.07% (95% CI, lower limit 58.97-63.33, upper limit 83.07-88.20 %); and for median red blood cell column width were 5.63-8.59 µm (95% CI, lower limit 5.28-6.07, upper limit 8.14-9.51 µm). There was a negative association between median red blood cell column width and body weight (p = 0.007). The median red blood cell column was significantly wider in intact females when compared to spayed females (p = 0.033). The GlycoCheck® analysis was easily performed in healthy sedated cats. Clinical variables did not have an effect on the EG thickness. These results suggest that this technique could be valuable for evaluation of the EG and microvascular parameters in cats.

Evaluation of jejunal microvasculature of healthy anesthetized dogs with sidestream dark field video microscopy.

OBJECTIVE: To determine the feasibility of sidestream dark field (SDF) video microscopy for the evaluation of the jejunal microvasculature of healthy dogs. ANIMALS: 30 healthy sexually intact female shelter dogs anesthetized for ovariohysterectomy. PROCEDURES: Preoperative physical and clinicopathologic assessments were performed to confirm health status. Then healthy dogs were anesthetized, and the abdomen was incised at the ventral midline for ovariohysterectomy and jejunal microvasculature evaluation. An SDF video microscope imaged the microvasculature of 2 sites of a portion of the jejunum, and recorded videos were analyzed with software capable of quantitating parameters of microvascular health. Macrovascular parameters (heart rate, respiratory rate, and hemoglobin oxygen saturation) were also recorded during anesthesia. RESULTS: Quantified jejunal microvascular parameters included valid microvascular density (mean ± SD, 251.72 ± 97.10 µm/mm), RBC-filling percentage (66.96 ± 8.00%), RBC column width (7.11 ± 0.72 µm), and perfused boundary region (2.17 ± 0.42 µm). The perfused boundary region and RBC-filling percentage had a significant negative correlation. Strong to weak positive correlations were noted among the perfused boundary regions of small-, medium-, and large-sized microvessels. No significant correlations were identified between microvascular parameters and age, body weight, preoperative clinicopathologic results, or macrovascular parameters. CONCLUSIONS AND CLINICAL RELEVANCE: Interrogation of the jejunal microvasculature of healthy dogs with SDF video microscopy was feasible. Results of this study indicated that SDF video microscopy is worth additional investigation, including interrogation of diseased small intestine in dogs.

Retrospective evaluation of acute kidney injury in dogs with pit viper envenomation (2008-2017): 56 cases.

OBJECTIVES: To describe the clinicopathological characteristics of dogs that develop acute kidney injury (AKI) secondary to pit viper envenomation, and to describe the association between development of AKI and clinical course and outcome. DESIGN: Retrospective study. SETTING: University teaching hospital. ANIMALS: Client-owned dogs treated with at least 1 vial of antivenom following pit viper envenomation and that had at least 2 plasma creatinine concentrations measured during the course of hospitalization. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Sixty-three dogs met the inclusion criteria. One was excluded due chronic kidney disease, and 6 were excluded due to nonsteroidal anti-inflammatory drug administration. Of the 56 dogs included in the study, 16 developed AKI (29%). Dogs with AKI received a significantly higher dose of antivenom, 8.7 ± 6.8 total vials versus dogs in the non-AKI group that received 4.2 ± 2.6 vials (P = 0.006). Dogs in the AKI group were significantly more tachycardic (P = 0.028), hypotensive (P = 0.002), had a higher shock index (P = 0.012), and were more likely to receive transfusions with packed red blood cells (P = 0.042) than dogs in the non-AKI group. No significant association was identified between the development of AKI and length of hospitalization. The only factors that were significantly associated with degree of severity of AKI included the receipt of blood transfusion (P = 0.006) and number of vials of antivenom administered (P = 0.03). The development of AKI was significantly associated with outcome (P < 0.001), with 5 of 16 (31%) dogs in the AKI group surviving to discharge, 7 of 16 (44%) dying, and 4 of 16 (25%) being euthanized versus 39 of 40 (98%) surviving to discharge in the non-AKI group and 1 of 40 (2%) dying in hospital. CONCLUSION: Development of AKI in dogs following pit viper envenomation carries an increased risk of mortality that is associated with severity of shock at presentation and increased doses of antivenom administration.

Persistent pit viper envenomation in a cat.

CASE SUMMARY: A 4-year-old female spayed, indoor/outdoor domestic mediumhair cat presented with multiple bleeding puncture wounds and hemorrhagic shock. The cat was diagnosed with suspected pit viper envenomation based on the location and appearance of the bite wounds, as well as the presence of severe coagulopathy with prolonged activated coagulation time (762 s), which responded to antivenom administration. The clinical course of the cat was unique owing to the prolonged clinical signs of envenomation that appeared as intermittent coagulopathy and hemorrhage over a 2 week period. Five vials of antivenom were administered and three units of packed red blood cells were transfused over a 7 day period. The cat made a complete recovery with cessation of hemorrhage and normalization of clotting times. RELEVANCE AND NOVEL INFORMATION: This is the first report of persistent pit viper venom-induced coagulopathy in the feline veterinary literature.

Clearance of plasma ivermectin with single pass lipid dialysis in 2 dogs.

OBJECTIVE: To describe the use of single pass lipid dialysis (SPLD) for treatment of ivermectin toxicosis in 2 Australian Shepherd dogs with the ABCB1-1Δ gene mutation. CASE SERIES SUMMARY: Two Australian Shepherd dogs were presented for treatment of ivermectin toxicosis. Dogs were initially treated with intravenous lipid emulsion and supportive care, without improvement of clinical signs. They both developed respiratory paralysis and required mechanical ventilation. In order to increase the clearance of circulating ivermectin, SPLD was performed using dialysate containing 5% lipid. Blood samples were obtained immediately before and after dialysis and analyzed for serum ivermectin concentration. Ivermectin reduction ratio was calculated at 29% and 39% for each dog, respectively. When compared to intrinsic total body ivermectin clearance, only the second dog had a relative improvement of plasma clearance following SPLD. Both dogs were confirmed to be homozygous for ABCB1-1Δ gene mutations. Both dogs remained ventilator dependent for several days and ultimately made a full recovery. NEW OR UNIQUE INFORMATION PROVIDED: SPLD may be an adjunctive detoxification strategy for highly lipophilic toxins such as ivermectin.