Kate Hopper

RECOVER evidence and knowledge gap analysis on veterinary CPR. Part 7: Clinical guidelines.

OBJECTIVE To present a series of evidence-based, consensus guidelines for veterinary CPR in dogs and cats. DESIGN Standardized, systematic evaluation of the literature, categorization of relevant articles according to level of evidence and quality, and development of consensus on conclusions for application of the concepts to clinical practice. Questions in five domains were examined: Preparedness and Prevention, Basic Life Support, Advanced Life Support, Monitoring, and Post-Cardiac Arrest Care. Standardized worksheet templates were used for each question, and the results reviewed by the domain members, by the RECOVER committee, and opened for comments by veterinary professionals for 4 weeks. Clinical guidelines were devised from these findings and again reviewed and commented on by the different entities within RECOVER as well as by veterinary professionals. SETTING Academia, referral practice and general practice. RESULTS A total of 74 worksheets were prepared to evaluate questions across the five domains. A series of 101 individual clinical guidelines were generated. In addition, a CPR algorithm, resuscitation drug-dosing scheme, and postcardiac arrest care algorithm were developed. CONCLUSIONS Although many knowledge gaps were identified, specific clinical guidelines for small animal veterinary CPR were generated from this evidence-based process. Future work is needed to objectively evaluate the effects of these new clinical guidelines on CPR outcome, and to address the knowledge gaps identified through this process.

Concurrent Diseases and Conditions in Dogs with Splenic Vein Thrombosis

BACKGROUND Splenic venous thrombosis (SVT) is usually considered an incidental finding on abdominal ultrasound examination but can indicate the presence of underlying disease. Concurrent disease processes and conditions in dogs with SVT have not been identified previously. OBJECTIVES To identify concurrent diseases and conditions in dogs with SVT. ANIMALS Eighty dogs with SVT. METHODS Retrospective review. Medical records from 1994 through 2008 were searched for dogs with SVT identified by ultrasound examination. These records were then reviewed for signalment, medical history, clinicopathologic testing, diagnostic imaging, and clinical diagnosis. RESULTS The most common concurrent conditions were neoplasia (54%), exogenous corticosteroid administration (43%), systemic inflammatory response syndrome (26%), disseminated intravascular coagulation (20%), pancreatitis (18%), and immune-mediated disease (16%). The most common neoplastic disease was lymphoma, and the most common immune-mediated disease was immune-mediated hemolytic anemia. Protein-losing nephropathy and naturally occurring hyperadrenocorticism were identified in <10% of the dogs. Concurrent splenic infarcts were identified in 33% of dogs, and concurrent portal vein thrombi were found in 18% of dogs. CONCLUSIONS SVT is a sonographic finding of clinical importance, and dogs with SVT can have 1 or more coexisting diseases.

Incidence, Nature, and Etiology of Metabolic Acidosis in Dogs and Cats

BACKGROUND Metabolic acidosis is an important abnormality in ill and injured dogs and cats. OBJECTIVES To describe the incidence, nature, and etiology of metabolic acidosis in dogs and cats that had arterial or venous blood gases measured for any reason at a university teaching hospital. ANIMALS Dogs and cats at the Veterinary Medical Teaching Hospital. METHODS Acid base parameters and electrolyte and lactate concentrations in dogs and cats measured during a 13-month period were retrospectively retrieved from a computer database. Metabolic acidosis was defined as a standardized base excess (SBE) in dogs of <-4 mmol/L and in cats <-5 mmol/L. RESULTS A total of 1,805 dogs and cats were included; of these, 887 (49%) were classified as having a metabolic acidosis (753 dogs and 134 cats). Primary metabolic acidosis was the most common disorder in dogs, whereas mixed acid base disorder of metabolic acidosis and respiratory acidosis was most common in cats. Hyperchloremic metabolic acidosis was more common than a high anion gap (AG) metabolic acidosis; 25% of dogs and 34% of cats could not be classified as having either a hyperchloremic metabolic acidosis or a high AG metabolic acidosis. CONCLUSIONS AND CLINICAL IMPORTANCE Metabolic acidosis was found commonly in this patient population and was associated with a wide variety of disease processes. Mixed acid base disorders occur frequently and routine categorization of metabolic acidosis based on the presence of high AG or hyperchloremia may be misleading in a large proportion of cases.

Airway microbial culture and susceptibility patterns in dogs and cats with respiratory disease of varying severity

OBJECTIVE To compare airway microbiological culture and susceptibility results in 2 groups of dogs and cats: 1 with respiratory failure requiring positive pressure ventilation (PPV) and 1 with respiratory disease. DESIGN Retrospective study. SETTING University teaching hospital. ANIMALS Fifty-two dogs and cats requiring PPV that had an airway microbiologic culture submitted from October 1, 2003 to October 31, 2008 were included. One hundred and four airway microbiologic cultures from dogs and cats with respiratory disease not requiring PPV were randomly sampled for comparison. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Patients with respiratory failure were more likely to have a gram-negative enteric isolate identified (P<0.001), while patients with respiratory disease were more likely to have a gram-negative nonenteric isolate (P<0.001) or anaerobic isolate (P<0.001) identified. Aerobic bacterial isolates from patients with respiratory failure were less likely to be susceptible to ampicillin (P=0.006), amoxicillin/clavulonate (P<0.001), chloramphenicol (P=0.004), enrofloxacin (P<0.001), ticarcillin/clavulonate (P=0.004), and the combination of ampicillin with enrofloxacin (P<0.001) than were aerobic bacterial isolates from patients with respiratory disease. CONCLUSIONS Canine and feline patients with respiratory failure severe enough to require PPV exhibit a different pattern of bacterial isolates cultured from their airways when compared with isolates from patients with respiratory disease that has not resulted in ventilator dependence. These isolates are more likely to be resistant to commonly used antimicrobials/antimicrobial combinations than patients in the respiratory disease group. These findings suggest that in canine and feline patients with infectious lower respiratory tract disease, consideration of the severity of the pulmonary insult may allow for better prediction of likely isolates and their antimicrobial susceptibilities. Further prospective studies with a standardized collection technique are warranted.

RECOVER evidence and knowledge gap analysis on veterinary CPR. Part 3: Basic life support.

OBJECTIVE To systematically examine the evidence on basic life support (BLS) in veterinary CPR and to determine knowledge gaps. DESIGN Standardized, systematic evaluation of the literature, categorization of relevant articles according to level of evidence and quality, and development of consensus on conclusions for application of the concepts to clinical practice. Relevant questions were answered on a worksheet template and reviewed by the Reassessment Campaign on Veterinary Resuscitation (RECOVER) BLS domain members, by the RECOVER committee and opened for comments by veterinary professionals for 30 days. SETTING Academia, referral practice, and general practice. RESULTS Sixteen worksheets were prepared to evaluate techniques for chest compression and ventilation strategies as well as identification of cardiopulmonary arrest (CPA). Major recommendations arising from this evidence review include performing chest compressions at a rate of at least 100/min at a compression depth of one-third to half the width of the chest with minimal pauses, and early instigation of ventilation at a rate of 8-10 breaths/min in intubated patients, or using a 30:2 compression/ventilation ratio in nonintubated patients. CONCLUSIONS Although veterinary clinical trials are lacking, much of the experimental literature on BLS utilized canine models. The major conclusions from this analysis of the literature are the importance of early identification of CPA, and immediate initiation of BLS in these patients. Many knowledge gaps exist, most importantly in our understanding of the optimal hand placement and technique for chest compressions, warranting coordinated future studies targeted at questions of relevance to differences between veterinary species and humans.

Diagnostic utility of D-dimer concentrations in dogs with pulmonary embolism.

BACKGROUND Pulmonary embolism (PE) is a complication of systemic disease in dogs. Antemortem diagnosis is challenging because of the lack of a confirmatory test. OBJECTIVES To retrospectively determine the diagnostic utility of D-dimer concentrations in dogs with necropsy-confirmed PE. ANIMALS Ten dogs with PE confirmed at necropsy that had D-dimer concentrations measured and 10 control dogs with D-dimer concentrations available that lacked PE on necropsy. METHODS The computerized medical record database was searched for dogs with necropsy-confirmed PE that had D-dimer concentrations measured at that visit. An age-, sex-, and breed-matched control group was identified. Signalment, location of PE, and coagulation profiles were collected. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated using a D-dimer concentration of 250 ng/mL. RESULTS Coagulation profiles were not different between dogs with and without PE. Using 250 ng/mL as a cut-off D-dimer concentration, the sensitivity and specificity were 80 and 30%, respectively, for the diagnosis of PE. The NPV and PPV were 60 and 53.0%, respectively. D-dimer concentration <103 ng/mL had 100% sensitivity for ruling out PE and no value was 100% specific. CONCLUSIONS AND CLINICAL IMPORTANCE D-dimer concentrations <250 ng/mL have a high sensitivity for the absence of PE, but PE still can occur in dogs with a normal D-dimer concentration. Increased D-dimer concentrations are not specific for PE.

Evaluation of acid–base disorders in dogs and cats presenting to an emergency room. Part 1: Comparison of three methods of acid–base analysis

OBJECTIVE To compare the diagnostic performance of the traditional approach to acid-base analysis with the Stewart approach and a semiquantitative approach. DESIGN Prospective cohort study. SETTING University teaching hospital. ANIMALS A total number of 84 dogs and 14 cats presenting to a university teaching hospital emergency room. PROCEDURES All dogs and cats in which venous blood samples for acid-base, lactate, and serum biochemical analysis were all collected within 60 minutes of each other, over a 5-month enrollment period. Acid-base analysis was performed using the traditional approach, Stewart approach, and a semiquantitative approach. RESULTS Traditional acid-base analysis identified respiratory acid-base abnormalities in 14/98 animals and metabolic acid-base abnormalities in 67/98. A mixed disorder of metabolic acidosis and respiratory alkalosis was most common occurring in 29/98 patients. The Stewart approach identified metabolic abnormalities in 82/98 patients; strong ion difference abnormalities were evident in 68/98 cases; an increased strong ion gap acidosis was identified in 49/98 cases; and changes in the quantity of weak acids in 25/98 cases. The semiquantitative approach identified abnormalities in all cases evaluated. Of the 14 patients with a primary respiratory acid-base abnormality, the Stewart approach identified metabolic abnormalities in 9 and the semiquantitative approach found abnormalities in all animals. CONCLUSIONS AND CLINICAL RELEVANCE The physicochemical approaches diagnosed more acid-base abnormalities in this population than the traditional approach although many of the abnormalities identified were small and of unknown clinical relevance. The physicochemical approaches may provide greater insight as to the underlying etiology of abnormalities, which maybe of particular relevance to cases with changes in albumin and/or phosphorus concentration.

Basics of Mechanical Ventilation for Dogs and Cats

Respiratory failure may occur due to hypoventilation or hypoxemia. Regardless of the cause, emergent anesthesia and intubation, accompanied by positive pressure ventilation, may be necessary and life saving. Long-term mechanical ventilation requires some specialized equipment and knowledge; however, short-term ventilation can be accomplished without the use of an intensive care unit ventilator, and can provide oxygen supplementation and carbon dioxide removal in critical patients.

The effect of hetastarch (670/0.75) on urine specific gravity and osmolality in the dog.

BACKGROUND Urine specific gravity (USG) is used clinically to estimate urine osmolality (UOsm). Although USG has been shown to have a linear correlation with UOsm in dogs, the relationship is altered when there are significant numbers of high molecular weight (MW) molecules in the urine. HYPOTHESIS USG would no longer predict UOsm in dogs given intravenous hetastarch (670/0.75)(HES). ANIMALS Eight healthy employee-owned adult dogs. METHODS Prospective, controlled experimental study. USG and UOsm were measured every 30 minutes from t=0 minutes to t=360 minutes. Dogs were administered 20 mL/kg of either NaCl 0.9% (control group, n=4) or HES (treatment group, n=8) IV over 1 hour starting at t=90 minutes. RESULTS There was a decrease in UOsm in both groups starting at t=120 minutes and continuing for the study duration, and there was no significant difference in UOsm between treatment and control groups across all time points. There was an appropriate decrease in USG from t=120 minutes for the control group. In the treatment group, USG increased significantly at t=120 minutes (P= .0006), t=150 minutes (P= .0002), and t=180 minutes (P= .0044). The largest increase in USG occurred at t=150 minutes with a mean USG of 1.070 +/- 0.021 (range 1.038-1.104). CONCLUSIONS AND CLINICAL IMPORTANCE Urine specific gravity should not be used to estimate urine solute concentration in dogs following the administration of 20 mL/kg of HES. In a clinical setting, the evaluation of USG following this dose of HES may lead to an overestimation of urine concentration.

Incidence, Severity and Prognosis Associated with Hypernatremia in Dogs and Cats

Background Hypernatremia has been associated with substantial morbidity and death in human patients. The incidence and importance of hypernatremia in dogs and cats has not been determined. Hypothesis/Objectives To describe the incidence of and prognosis associated with hypernatremia in dogs and cats at a university teaching hospital. Animals A total of 16,691 dogs and 4,211 cats with measured blood or serum sodium concentration. Methods Retrospective study. Medical records of animals with a blood or serum sodium concentration measured during a 60‐month period were reviewed to determine the severity of hypernatremia and its associated case fatality rate. Cases with moderate (11–15 mmol/L above the reference range) or severe hypernatremia (≥16 mmol/L above the reference range) were further reviewed. Results A total of 957 dogs (5.7%) and 338 cats (8.0%) were diagnosed with hypernatremia. Case fatality rates of dogs and cats with hypernatremia was 20.6 and 28.1%, respectively compared to 4.4 and 4.5% with a normal blood or serum sodium concentration (P < .0001). The magnitude of hypernatremia was linearly associated with a higher case fatality rate (P < .0001). Hypernatremia was associated with a higher case fatality rate than hyponatremia. Among the animals with moderate or severe hypernatremia, 50% of dogs and 38.5% of cats presented with community‐acquired hypernatremia, and 50% of dogs and 61.5% of cats developed hospital‐acquired hypernatremia. Conclusions and clinical importance Hypernatremia was found infrequently in this population but was associated with increased case fatality rates in dogs and cats. Presence and severity of hypernatremia might be useful as a prognostic indicator.