Showing papers in "Journal of Veterinary Emergency and Critical Care in 2010"

Bartonellosis: an emerging infectious disease of zoonotic importance to animals and human beings

Abstract: Objective – To provide a review of clinically relevant observations related to Bartonella species as emerging pathogens in veterinary and human medicine. Data Sources – Literature as cited in PubMed and as generated by each of the authors who have contributed to various aspects of the clinical understanding of bartonellosis. Human Data Synthesis – Important historical and recent publications illustrating the evolving role of animal reservoirs as a source of human infection. Veterinary Data Synthesis – Comprehensive review of the veterinary literature. Conclusions – In addition to inducing life-threatening illnesses, such as endocarditis, myocarditis, and meningoencephalitis and contributing to chronic debilitating disease, such as arthritis, osteomyelitis, and granulomatous inflammation in cats, dogs, and potentially other animal species; pets and wildlife species can serve as persistently infected reservoir hosts for the transmission of Bartonella spp. infection to veterinary professionals and others with direct animal contact.

Traumatic brain injury: a review of pathophysiology and management

Abstract: Objective – To review current information regarding the pathophysiology associated with traumatic brain injury (TBI), and to outline appropriate patient assessment, diagnostic, and therapeutic options. Etiology – TBI in veterinary patients can occur subsequent to trauma induced by motor vehicle accidents, falls, and crush injuries. Primary brain injury occurs at the time of initial impact as a result of direct mechanical damage. Secondary brain injury occurs in the minutes to days following the trauma as a result of systemic extracranial events and intracranial changes. Diagnosis – The initial diagnosis is often made based on history and physical examination. Assessment should focus on the cardiovascular and respiratory systems followed by a complete neurologic examination. Advanced imaging may be indicated in a patient that fails to respond to appropriate medical therapy. Therapy – Primary brain injury is beyond the control of the veterinarian. Therefore, treatment should focus on minimizing the incidence or impact of secondary brain injury. Because of a lack of prospective or retrospective clinical data, treatment recommendations for veterinary TBI patients are primarily based on human and experimental studies and personal experience. Therapeutic guidelines have been developed that center on maintaining adequate cerebral perfusion. Prognosis – Severe head trauma is associated with high mortality in humans and animals. However, dogs and cats have a remarkable ability to compensate for loss of cerebral tissue. It is therefore important not to reach hasty prognostic conclusions based on initial appearance. Many pets go on to have a functional outcome and recover from injury.

Canine angiostrongylosis: an emerging disease in Europe

Abstract: Objective – The aim of this article is to review Angiostrongylus vasorum infection in dogs, including the life cycle, signalment, clinical signs, diagnosis, and treatment. Apparent changes in the epidemiology of this unique parasite are considered, alongside information available regarding its recent geographic spread. Etiology – A. vasorum is a metastrongyloid parasite capable of causing an array of clinical problems in dogs, including cardiorespiratory, coagulopathic, and neurologic signs. Currently, the parasite has a worldwide distribution; however, it usually arises in small pockets of enzootic foci. Recent reports suggest a changing distribution of this parasite, which has renewed interest in its epidemiology and in the risk of expansion to new areas including mainland North America. Diagnosis – A definitive diagnosis of angiostrongylosis is usually made using the modified Baermann technique either using feces or tracheobronchial secretions; however, this review also discusses novel methods such as serologic and molecular techniques. Therapy – Once a diagnosis of angiostrongylosis is made, prompt treatment should follow with anthelmintic drugs (such as moxidectin/imidacloprid, milbemycin oxime, or fenbendazole) and supportive care dependent upon the patient's clinical signs. Currently, there is no proven prophylactic regime. Prognosis – The prognosis appears to be very dependent upon the severity of clinical signs at presentation. A. vasorum can be fatal and death may be sudden. However, if a prompt diagnosis is made and appropriate treatment is administered complete clinical resolution is possible.

Comparison of ultrasonic Doppler flow monitor, oscillometric, and direct arterial blood pressure measurements in ill dogs

Abstract: Objective – To compare blood pressure measurements obtained via ultrasonic Doppler flow monitor (DOP) and 2 oscillometric noninvasive blood pressure monitors (CAR and PAS) to invasive blood pressure (IBP) in hospitalized, conscious dogs with a range of blood pressures. Design – Prospective clinical study. Setting – University teaching hospital. Animals – Eleven client-owned dogs aged between 4 months and 11.5 years (median 6 y), and weighing between 5.8 and 37.5 kg (median 30.2 kg). Interventions – Blood pressure measurement. Measurements and Main Results – Three consecutive measurements of systolic, diastolic, and mean arterial pressure (MAP) were recorded for each of the 3 indirect devices (only systolic for DOP), along with concurrent IBP measurements. The data were categorized into 3 groups: hypotensive (direct MAP 100 mm Hg). Each indirect method was compared with the corresponding direct arterial pressure using the Bland-Altman method. Within the hypotensive group, each indirect method overestimated the corresponding IBP. Within the normotensive group all indirect systolic measurements and the PAS diastolic measurements underestimated the corresponding IBP. The remaining indirect measurements overestimated the corresponding IBP. Within the hypertensive group, DOP and CAR systolic measurements underestimated the corresponding IBP, and the remaining indirect measurements overestimated the corresponding IBP. In hypertensive dogs oscillometric systolic measurements were more accurate than MAP. In hypotensive dogs MAP measurements were more accurate than systolic measurements. All indirect measurements were most accurate in hypertensive dogs. Conclusions – The noninvasive blood pressure monitors in our study did not meet the validation standards set in human medicine. However, CAR diastolic and MAP measurements within the normotensive group, CAR MAP measurements within the hypertensive group, and PAS diastolic measurements in all groups were close to these standards. All indirect measurements showed greater bias during hypotension. Precision was poorer for all indirect systolic measurements than for MAP.

Clinical management of canine babesiosis.

Abstract: Objective – To review and summarize current information regarding epidemiology, pathogenesis, and pathophysiology leading to the various clinical syndromes associated with canine babesiosis. Diagnosis, treatment, preventative strategies, and zoonotic implications are discussed. Etiology – Babesiosis is caused by hemoprotozoa of the genus Babesia. Numerous species of Babesia exist worldwide. An increased incidence of babesiosis is described, especially in North America. The babesial organism spends the majority of its life cycle within the erythrocyte of the definitive host, resulting in hemolysis, with or without systemic complications. Diagnosis – Definitive diagnosis depends on direct visualization of the organism on blood smear or polymerase chain reaction. A positive serologic antibody test indicates exposure with or without active infection. Therapy – Antiprotozoal drugs, antimicrobials, and supportive care are the mainstays of babesiosis therapy. Prognosis – Prognosis depends on the severity of disease, which in turn depends on both organism and host factors. Clinical syndromes associated with a poorer prognosis include red biliary syndrome, acute renal failure, acute respiratory distress syndrome, neurologic dysfunction, acute pancreatitis, cardiac dysfunction, and hypoglycemia.

A veterinary perspective on methicillin-resistant staphylococci.

Abstract: Objective – To familiarize the reader with the epidemiology, diagnosis, and infectious and zoonotic potential of methicillin-resistant staphylococci. Data sources – Original research publications, scientific reviews and abstracts, case reports, and conference proceedings. Human Data Synthesis – Staphylococcus aureus is a common human commensal organism; acquisition of genes encoding an altered penicillin-binding protein confers resistance to β-lactam antimicrobial drugs. Methicillin-resistant S. aureus (MRSA) are often resistant to non–β-lactam antimicrobial drugs as well. Originally described as an important cause of nosocomial infection, MRSA colonization and infection are now often identified in humans outside healthcare settings. Like other S. aureus, MRSA may be present without clinical illness. However, when they do cause infection the consequences can be extremely serious. Veterinary Data Synthesis – The major domestic animal species, including pets and livestock, may become contaminated, colonized, or infected with methicillin-resistant staphylococci, including MRSA. Dogs and cats are more likely to be colonized/infected with Staphylococcus pseudintermedius than S. aureus, but this pathogen can acquire genes encoding methicillin resistance (ie, MRSP). Diagnosis of MRSA or MRSP has implications not only for treatment of infected animals, but for potential zoonotic transmission. Conclusions – MRSA infection is an important cause of morbidity and mortality in humans. Animals may be contaminated, colonized, or infected with MRSA, with implications for the animal's health and as a potential reservoir for human infection. Staphylococci other than S. aureus may also acquire genes for methicillin resistance, and these species can also result in animal and occasionally human morbidity or mortality.

Effects of nutritional support on hospital outcome in dogs and cats.

Abstract: Objective – Investigate the effects of assisted nutritional support on hospital outcome in dogs and cats, and the relationship between hospital outcome and energy intake, body condition score (BCS), physical status score, and type of nutritional support used. Design – Retrospective analysis of hospitalized animals. Setting – Teaching Veterinary Hospital. Animals – Four hundred and sixty-seven dogs and 55 cats. Interventions – Routine clinical nutritional support. Measurements and Main Results – The following variables were recorded for each animal: energy intake, body weight at admission and discharge, BCS, physical status score, and type of nutritional support used. Disease severity was negatively associated with hospital outcome and energy intake (P 5 0.009). Energy intake was positively associated with hospital discharge (Po0.001). Outcome may be related to BCS, with discharge rates of 73% for animals with low BCS, and 84.7% for those at an ideal BCS or overweight (P 5 0.04). Sixty-four percent of animals showed voluntary food intake (92.9% were discharged), 19.0% received enteral support (71.8% were discharged), 7.0% were forced fed (75.0% were discharged), 6.0% received parenteral support (61.9% were discharged), and 4.0% did not receive calories (38.4% were discharged), suggesting a possible relationship between the type of nutritional support, energy intake, and outcome (P 5 0.009). Conclusions – Energy supply, even if modest and close to resting energy requirements appears to be positively associated with hospital discharge. However, disease severity was the main negative factor on outcome and also had a negative effect on energy intake, making it difficult to separate the effects of both factors when interpreting hospital discharge. Thin animals with low BCS had greater mortality.

Immunomodulatory effects of opioids.

Abstract: Objective – To review the immunomodulatory effects of opioids. Data Sources – Original research publications and review articles using the PubMed search engine with the following keywords – opioids, morphine, immuomodulation, and immunosuppression. Veterinary and Human Data Synthesis – Opioids have been shown to modulate the immune system in animal models by affecting both the acquired and innate arms of the immune system. Natural killer cell activity, T-cell proliferation, antibody production, phagocytic cell function, and cytokine production have all been shown to be affected by opioids. Many of these effects are reversed by opioid antagonists. Opioids have also been shown to induce sepsis in laboratory animals. Opioid administration alters immune parameters in healthy humans at analgesic doses and may increase the risk of infection in some patient populations. Conclusions – While opioids remain the most powerful and widely used analgesics available, their negative effects on the immune system are well established in the laboratory setting. Thoughtful consideration should be given to the use of certain opioids in critically ill patients, especially those with pre-existing immunocompromise.

Potential risks, prognostic indicators, and diagnostic and treatment modalities affecting survival in dogs with presumptive aspiration pneumonia: 125 cases (2005-2008)

Abstract: Objective – To evaluate a clinical population of dogs diagnosed with presumptive aspiration pneumonia (AP) and determine diagnostic and treatment modalities contributing to survival. Design – Retrospective study. Setting – A university veterinary teaching hospital in an urban setting. Animals – One hundred and twenty-five dogs with presumed AP treated from 2005 to 2008. Interventions – None. Measurements and Main Results – Dogs with presumptive AP identified by a review of medical records had an overall survival of 81.6% (102/125). Male large-breed dogs (mean 24.9 kg; 82/125) were overrepresented and were more likely to develop AP in this study population. Recent anesthesia had been performed in 16% (20/125), and vomiting was reported in 64% (80/125). The most common radiographic findings were a predominantly alveolar pattern (187/272, [68.8%] total lung lobes) in the right middle lung lobe (80/115, [69.6%]). A mean of 2 lung lobes were involved radiographically, and the relationship between survival and the number of lung lobes affected was statistically significant (P=0.04). Neutrophilia with a left shift was common with no significant change on consecutive daily evaluations. The mean PaO2 was 77.7 mm Hg (SD, 17.5 mm Hg) (range, 40.7–100 mm Hg) with a median alveolar-arterial gradient of 41.1 mm Hg (range, 8.1–81.8 mm Hg). In this study population, 37.6% (47/125) of dogs had microbial cultures performed and of these, 76.6% (36/47) were positive for growth; Escherichia coli (38.8%), Mycoplasma spp. (21.3%), Pasturella spp. (19.1%), and Staphylococcus spp. (17%) were the most common isolates in either single or multiagent infections. No treatment modality was statistically associated with increased survival. Colloid therapy was a negative prognostic indicator. Conclusions – In this study the overall prognosis for AP was good. Patients with only 1 affected lung lobe appeared more likely to survive. Supportive treatment modalities are warranted for the hospitalized patient, although no individual treatment method was found to be clearly superior to others.

Feline hemotropic mycoplasmas

Abstract: Objective – To describe the current understanding of the etiology, pathogenesis, diagnosis, and treatment of feline hemotropic mycoplasmosis (feline infectious anemia). Data Sources – Manuscripts published on hemotropic mycoplasmosis in cats and other animal species, based on a search of PubMed using the search terms ‘hemoplasmas,’‘haemoplasmas,’‘hemotropic,’‘haemotropic,’ and ‘Haemobartonella,’ as well as references published within manuscripts accessed. Human Data Synthesis – Although hemotropic bacteria such as Bartonella bacilliformis have been recognized in humans for over 100 years, it has only been in recent years that some of these have been identified as hemotropic mycoplasmas. Veterinary Data Synthesis – Three species of hemotropic mycoplasmas have been documented in cats worldwide, Mycoplasma haemofelis, ‘Candidatus Mycoplasma turicensis,’ and ‘Candidatus Mycoplasma haemominutum.’ These organisms were previously known as Haemobartonella felis, but are now known to be mycoplasmas. M. haemofelis is the most pathogenic species, and causes anemia in immunocompetent cats. Although ‘Candidatus Mycoplasma turicensis’ and ‘Candidatus Mycoplasma haemominutum’ may be more capable of causing anemia in immunosuppressed cats, their pathogenicity remains controversial. Assays based on polymerase chain reaction technology are the most sensitive and specific diagnostic tests available for these organisms, because they remain uncultivable in the laboratory setting. Blood smears are unreliable for diagnosis of hemoplasmosis because of their lack of sensitivity and specificity. Conclusions – Cats presenting to emergency/critical care specialists with hemolytic anemia should be tested using polymerase chain reaction assays for hemotropic mycoplasmas before instituting antimicrobial therapy. Positive test results for M. haemofelis suggest involvement of this organism in hemolytic anemia. Other differential diagnoses for hemolytic anemia should be considered in cats testing positive for ‘Candidatus Mycoplasma turicensis’ and ‘Candidatus Mycoplasma haemominutum,’ because the presence of these organisms is not always associated with anemia. Blood from infected cats should be handled with care because of the potential zoonotic nature of this infection.

Evaluation of an indirect oscillometric blood pressure monitor in normotensive and hypotensive anesthetized dogs.

Abstract: Objective – To determine the accuracy and precision of an oscillometric noninvasive blood pressure device as a predictor of invasive direct blood pressure in healthy anesthetized hypotensive and normotensive dogs. Design – Prospective observational study. Setting – University teaching hospital. Animals – Eight crossbred adult dogs. Interventions – Anesthesia was induced with propofol and maintained with isoflurane. A catheter was placed in the dorsal pedal artery to record systolic, mean, and diastolic arterial blood pressures (aSAP, aMAP, and aDAP, respectively). The noninvasive blood pressure device cuff was placed around the contralateral front limb to record noninvasive systolic, mean, and diastolic blood pressure (nSAP, nMAP, and nDAP). Two states of blood pressure (BP) were studied: baseline state was established by keeping end-tidal isoflurane concentration at 1.2±0.1%. The hypotensive state was achieved by maintaining the same isoflurane concentration while withdrawing approximately 40% of the animal's blood volume until aMAP was stable at approximately 40 mm Hg. At the end of the study, blood was returned to the animal and it was allowed to recover from anesthesia. Measurements and Main Results – Agreement between the direct and indirect BP measurements was determined by the Bland-Altman method. The SAP and MAP but not DAP bias varied significantly between each BP state. Normotensive absolute biases (mean [SD]) for SAP, MAP, and DAP were −14.7 mm Hg (15.5 mm Hg), −16.4 mm Hg (12.1 mm Hg), and −14.1 mm Hg (15.8 mm Hg), respectively. Absolute biases during the hypotensive state for SAP, MAP, and DAP were −32 mm Hg (22.6 mm Hg), −24.2 mm Hg (19.5 mm Hg), and −16.8 mm Hg (17.2 mm Hg), respectively. Conclusion – The oscillometric device was not reliably predictive of intra-arterial BP during hypotension associated with acute hemorrhage.

Hyperbaric oxygen therapy. Part 1: history and principles.

Abstract: Objective – Review the historical development and physiologic principles of hyperbaric oxygen therapy (HBOT) based on human and veterinary experimental literature and current equipment in use. Data Sources – Review of basic physiologic concepts. Data from human and veterinary journals were reviewed through Pubmed and Veterinary Information Network database searches as well as reference searches on several articles covering hyperbaric therapy in clinically applicable situations. Human Data Synthesis – HBOT has been gaining acceptance as an adjunctive treatment in human medicine. The understanding of the physiology and application of hyperbaric therapy is increasing through ongoing research and greater access to hyperbaric equipment. Veterinary Data Synthesis – Several animal models have been utilized to examine the effects of HBOT. Most models utilize dogs and rats but pigs, cats, and other species have been studied. Conclusions – Hyperbaric therapy utilizes several physiologic principles of how gases respond under pressure and more specifically of how oxygen responds under pressure. The increase in concentration of oxygen in solution, based on its solubility under pressure, increases the diffusion gradient for its delivery deeper into tissues, which is the premise of HBOT. Ultimately the increases in dissolved oxygen generated by hyperbaric therapy have several physiologic effects that can alter tissue responses to disease and injury. As this technology becomes more available to clinical practice, HBOT should be considered as a therapeutic option.

Hyperbaric oxygen therapy. Part 2: application in disease.

Abstract: Objective – Review the mechanisms of action and clinical application of hyperbaric oxygen therapy (HBOT) based on human and veterinary clinical and experimental literature. Data Sources – Pubmed and Veterinary Information Network databases were searched for human and veterinary journal articles on hyperbaric therapy in clinically applicable situations. Historical reference searches on several articles in addition to basic physiologic concepts were also reviewed. Human Data Synthesis – HBOT has gained acceptance as an adjunctive treatment in clinical conditions other than diving-related injuries, such as select problem wounds and central nervous system diseases, in human medicine. Access to hyperbaric therapy has increased and ongoing research has furthered understanding of the mechanisms and potential therapeutic uses of HBOT. Veterinary Data Synthesis – Several animal models have been utilized to examine the effects of HBOT; primarily rodents (mice, rats) and rabbits but also dogs, cats, and pigs. Data related to animal model research as it pertains to clinical application of HBOT is reviewed. Conclusions – There is a substantial body of literature that has examined the adverse and beneficial effects of HBOT in animal models. As technology becomes more readily available to clinical practice and more clinical trials are performed to define its effectiveness, HBOT may be considered as an additional therapeutic option in many conditions including select problem wounds, spinal cord injury, and cerebral ischemic injury. Understanding the mechanisms by which HBOT exerts its effects will help guide research and use of the modality in clinical patients.

The association of blood lactate concentration with outcome in dogs with idiopathic immune-mediated hemolytic anemia: 173 cases (2003-2006)

Abstract: Objective – To determine the association of blood lactate with outcome and response to transfusion therapy in dogs with idiopathic immune-mediated hemolytic anemia (IMHA). Design – Retrospective study. Setting – Urban veterinary small animal emergency hospital. Animals – One hundred and seventy-three client-owned dogs with IMHA. Interventions – None. Measurements and Main Results – Serial blood lactate concentration, therapeutic interventions, and outcome were recorded. Nonsurvivors were defined as those that died or were euthanized. One hundred and thirty-three dogs (77%) survived, 35 (20%) were euthanized, and 5 (3%) died. One hundred forty-five dogs (84%; 145/173) had a lactate concentration above the laboratory reference interval [0.46–2.31 mmol/L] on presentation. Blood lactate at presentation was higher in the nonsurvivors (median 4.8 mmol/L; 0.5–13.6) compared with survivors (median 2.9 mmol/L; 0.3–13.2) (P<0.01). All dogs presenting with hyperlactatemia that normalized (<2.0 mmol/L) within 6 hours of admission survived, whereas, 71% of dogs that had a persistent hyperlactatemia at 6 hours survived (P=0.034). Lactate was positively correlated with age, BUN, and alkaline phosphatase, and inversely correlated with PCV. Receiver operating curve analysis for lactate concentration at admission as a test for outcome had an area under the curve of 0.69 with an optimal lactate cutoff concentration of 4.4 mmol/L correctly predicting outcome 73% of the time (sensitivity 60%, specificity 77%). Conclusions – Lactate concentration at presentation was significantly higher in nonsurvivors than survivors. Lactate was significantly correlated with previously reported outcome variables but lactate concentration at admission, as a predictor for outcome was less than optimal. However, serial lactate concentration measurements may be more predictive as patients with persistent hyperlactatemia 6 hours after admission were less likely to survive. Prospective studies evaluating serial lactate concentration while controlling for other variables may provide further insight into lactate measurement as a prognostic indicator in animals with IMHA.

Administration of 5% Human Serum Albumin in Critically Ill Small Animal Patients With Hypoalbuminemia: 418 Dogs and 170 Cats (1994-2008)

Abstract: Objectives – To describe the administration of 5% human serum albumin (HSA) in 588 critically ill hypoalbuminemic dogs and cats, and report outcome to discharge, changes in albumin concentration, and adverse effects during hospitalization. Design – Retrospective clinical study. Setting – Private emergency and general veterinary center. Animals – Client-owned dogs and cats. Interventions – None. Measurements and Main Results – The medical records of 588 critically ill hypoalbuminemic animals (418 dogs and 170 cats) were reviewed. All animals had hypoalbuminemia (serum albumin <20 g/L [2.0 mg/dL]) at admission, received an infusion of 5% HSA, and received no other colloid infusion. The HSA solution was administered through a peripheral vein at 2 mL/kg/h for 10 h/d (total volume 20 mL/kg/d) until albumin reached 20 g/L. The number of days of HSA infusion (median and range) was 4 days (2–11 d) for dogs and 3 days (2–7 d) for cats. Three hundred and sixteen dogs (75.6%) survived to discharge; 56 of 418 (13.4%) died in hospital. One hundred and twenty-three cats (72.3%) survived to discharge; 21 of 170 (12.4%) died in hospital. Severe hypersensitivity reactions such as anaphylaxis, angioedema, and urticaria were not noted. Interruption of albumin infusion and specific treatment of reactions were not required in any animal. Conclusions – In this study, administration of 5% HSA appeared to be safe in a large group of critically ill, hypoalbuminemic dogs and cats. The results should be interpreted with caution due to the retrospective, descriptive nature of the study, the absence of control groups and the lack of follow-up data, as well as the potentially life-threatening complications of HSA administration.

Evaluation of acute congestive heart failure in dogs and cats: 145 cases (2007–2008)

Abstract: Objective – To characterize the clinical presentation, management, and in-hospital outcomes of dogs and cats diagnosed with acute congestive heart failure (CHF). Design – Retrospective study of animals seen between January 2007 and May 2008. Setting – Emergency service at a university teaching hospital. Animals – Ninety dogs and 55 cats with CHF. Measurements and Main Results – Patient characteristics, including age, clinical signs, clinicopathologic abnormalities, diagnostic testing, and outcome were recorded. Forty-eight of the animals already were receiving cardiac medications at the time of presentation. The most common diseases represented were chronic valvular disease and cardiomyopathies. Cats had significantly lower median body temperature at admission compared with dogs (P<0.001). The most common abnormalities were elevated lactate (64%), elevated BUN (52%), hypochloremia (31%), hyperglycemia (27%), and elevated liver enzymes (26%). Many of these became even more prevalent during hospitalization. One hundred and sixteen animals were discharged from the hospital, for a survival rate of 80%. There was no survival difference between dogs and cats (P=0.39). Dogs that developed hypokalemia during hospital stay (P=0.04) were more likely to survive compared with those without hypokalemia and initial body temperature was lower for those cats that did not survive (P=0.02). Of those that did not survive, the majority were euthanized (n=25), while 4 dogs died. Conclusions – Dogs and cats presented to the emergency service with CHF had a high survival rate. In cats, initial body temperature was lower for those cats that did not survive. Although clinicopathologic abnormalities were common in both species, only dogs with hypokalemia had improved survival to hospital discharge.

Controversies related to red blood cell transfusion in critically ill patients

Abstract: Objective – To review the evolution of and controversies associated with allogenic blood transfusion in critically ill patients. Data sources – Veterinary and human literature review. Human Data Synthesis – RBC transfusion practices for ICU patients have come under scrutiny in the last 2 decades. Human trials have demonstrated relative tolerance to severe, euvolemic anemia and a significant outcome advantage following implementation of more restricted transfusion therapy. Investigators question the ability of RBCs stored longer than 2 weeks to improve tissue oxygenation, and theorize that both age and proinflammatory or immunomodulating effects of transfused cells may limit efficacy and contribute to increased patient morbidity and mortality. Also controversial is the ability of pre- and post-storage leukoreduction of RBCs to mitigate adverse transfusion-related events. Veterinary Data Synthesis – While there are several studies evaluating the transfusion trigger, the RBC storage lesion and transfusion-related immunomodulation in experimental animal models, there is little research pertaining to clinical veterinary patients. Conclusions – RBC transfusion is unequivocally indicated for treatment of anemic hypoxia. However, critical hemoglobin or Hct below which all critically ill patients require transfusion has not been established and there are inherent risks associated with allogenic blood transfusion. Clinical trials designed to evaluate the effects of RBC age and leukoreduction on veterinary patient outcome are warranted. Implementation of evidence-based transfusion guidelines and consideration of alternatives to allogenic blood transfusion are advisable.

Trends in plasma transfusion at a veterinary teaching hospital: 308 patients (1996-1998 and 2006-2008)

Abstract: Objectives – To describe changes in fresh frozen plasma (FFP) utilization over a 10-year period at a veterinary teaching hospital. To evaluate the effect of FFP administration on specific laboratory parameters. Design – Retrospective observational study. Setting – University teaching hospital. Animals– Two hundred and eighty-three dogs and 25 cats. Interventions – A hospital database search was performed for all animals receiving FFP during the study periods. Measurements and Main Results – Medical records of patients receiving plasma transfusions from 2006 to 2008 and from 1996 to 1998 were reviewed. Data collected included indications for transfusion, transfused volume, concurrent therapies, clinicopathologic data pre- and post-transfusion, transfusion reactions, days of hospitalization, and outcome. FFP was administered to 112 dogs and 23 cats from 2006 to 2008 and to 171 dogs and 2 cats from 1996 to 1998. Significantly fewer patients received FFP for the treatment of hypoalbuminemia (2006–2008: 15% versus 1996–1998: 53%; P<0.001) or pancreatitis (2006–2008: 2% versus 1996–1998: 13%; P=0.001) and significantly more patients received FFP for coagulopathy (2006–2008: 80% versus 1996–1998: 31%; P<0.001) in the 2006–2008 group compared with the 1996–1998 group. For all patients receiving FFP, there was no difference in mean serum albumin concentration pre- and post-transfusion. Median prothrombin time and activated partial thromboplastin time were significantly decreased post FFP administration. No association was found between the volume of plasma administered and outcome. Conclusions – FFP utilization has changed significantly over a 10-year period. FFP was used most commonly in 2006–2008 for the correction of coagulopathy. FFP administration was associated with significant reduction in prothrombin time and activated partial thromboplastin time but did not significantly alter albumin concentration when administered at median doses of 15–18 mL/kg.

Accuracy of a continuous glucose monitoring system in dogs and cats with diabetic ketoacidosis

Abstract: Objective – (1) To determine the ability of a continuous interstitial glucose monitoring system (CGMS) to accurately estimate blood glucose (BG) in dogs and cats with diabetic ketoacidosis. (2) To determine the effect of perfusion, hydration, body condition score, severity of ketosis, and frequency of calibration on the accuracy of the CGMS. Design – Prospective study. Setting – University Teaching Hospital. Animals – Thirteen dogs and 11 cats diagnosed with diabetic ketoacidosis were enrolled in the study within 24 hours of presentation. Interventions – Once BG dropped below 22.2 mmol/L (400 mg/dL), a sterile flexible glucose sensor was placed aseptically in the interstitial space and attached to the continuous glucose monitoring device for estimation of the interstitial glucose every 5 minutes. Measurements and Main Results – BG measurements were taken with a portable BG meter every 2–4 hours at the discretion of the primary clinician and compared with CGMS glucose measurements. The CGMS estimates of BG and BG measured on the glucometer were strongly associated regardless of calibration frequency (calibration every 8 h: r=0.86, P<0.001; calibration every 12 h: r=0.85, P<0.001). Evaluation of this data using both the Clarke and Consensus error grids showed that 96.7% and 99% of the CGMS readings, respectively, were deemed clinically acceptable (Zones A and B errors). Interpatient variability in the accuracy of the CGMS glucose measurements was found but was not associated with body condition, perfusion, or degree of ketosis. A weak association between hydration status of the patient as assessed with the visual analog scale and absolute percent error (Spearman's rank correlation, ρ=−0.079, 95% CI=−0.15 to −0.01, P=0.03) was found, with the device being more accurate in the more hydrated patients. Conclusions – The CGMS provides clinically accurate estimates of BG in patients with diabetic ketoacidosis.

High‐mobility group box 1 as a surrogate prognostic marker in dogs with systemic inflammatory response syndrome

Abstract: Objective – To evaluate various surrogate markers associated with the inflammatory and counter-inflammatory responses with respect to mortality in dogs with systemic inflammatory response syndrome (SIRS). Design – Prospective observational study. Setting – Veterinary Teaching Hospital. Animals – Twenty-eight dogs with naturally occurring diseases and SIRS from January 2007 to May 2009. Interventions – Upon admission to the veterinary hospital, history and baseline data from the physical examination, including parameters previously defined for meeting SIRS criteria, were documented. Heparinized blood samples were collected and plasma cytokines interleukin-6 (IL-6), IL-10, and high-mobility group box 1 (HMGB1) were measured by sandwich ELISA. Measurements and Main Results – In nonsurvivors, median plasma HMGB1 concentrations (0.718 μg/L, interquartile range [IQR]; 0.300–1.626 μg/L) and the ratio of HMGB1 to IL-10 (2.236, IQR; 0.972–5.367) were significantly increased as compared with those found in survivors (0.300 μg/L, IQR; 0.300–0.312 μg/L for HMGB1; 1.017, IQR; 0.862–1.126 for the ratio of HMGB1 to IL-10, P=0.007 and 0.024, respectively). Plasma IL-6, IL-10, and the ratio of IL-6 to IL-10 were not significantly different between groups. Among the parameters studied, HMGB1 and the ratio of HMGB1 to IL-10 performed the best in discriminating outcome in dogs with SIRS according to receiver operator characteristic curve analysis. Conclusions – Increases in plasma HMGB1 concentration and the ratio of HMGB1 to IL-10 may predict poorer outcomes in dogs with SIRS. The approach described may lead to reliable prognostic biomarkers and new therapeutic concepts in the study of SIRS in dogs.

Age-associated changes to pathogen-associated molecular pattern-induced inflammatory mediator production in dogs.

Abstract: Objective – To determine whether older dogs will have a more pronounced pro-inflammatory response and blunted anti-inflammatory response to pathogen-associated molecular patterns (PAMPs) compared with younger dogs. Design – Prospective. Setting – University teaching hospital. Animals – Thirty-eight privately owned sexually altered dogs of various ages. Interventions – Blood was collected for HCT, WBC count, plasma biochemical analysis, and whole blood culture. Whole blood was stimulated with lipopolysaccharide (LPS) or, lipoteichoic acid or, peptidoglycan or, addition of phosphate-buffered saline. Tumor necrosis factor (TNF), interleukin (IL)-6, and IL-10 production from whole blood were compared among young, middle aged, and geriatric dogs. Measurements and Main Results – LPS, lipoteichoic acid, and peptidoglycan stimulated significant TNF, IL-6, and IL-10 production from canine whole blood compared with phosphate-buffered saline. Whole blood from geriatric dogs had a blunted IL-10 response to LPS stimulation and middle-aged dogs had increased LPS-induced TNF production compared with the other groups. Conclusion – PAMPs from gram-positive and gram-negative bacteria stimulate TNF, IL-6, and IL-10 production from canine whole blood. The inflammatory mediator response to PAMPs from gram-negative bacteria alters with age and may be one factor contributing to mortality in geriatric dogs with sepsis.

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

Abstract: 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.

Spurious hypercreatininemia: 28 neonatal foals (2000–2008)

Abstract: Objectives – To (1) determine the occurrence of spurious hypercreatininemia in a population of hospitalized foals <2 days old, (2) assess the resolution of the hypercreatininemia, and (3) determine its association with survival in these foals. Design – Retrospective case series. Setting – 2 Referral hospitals. Animals – Foals 442 μmol/L (>5.0 mg/dL) from 2 referral hospitals. Interventions – None. Measurements and Main Results – The medical records of 33 foals were reviewed. Twenty-eight had spurious hypercreatininemia and 5 had acute renal failure. Admission creatinine was not significantly different between the 2 groups (mean [standard deviation]). The creatinine was 1,202 μmol/L (663 μmol/L) (13.6 mg/dL [7.5 mg/dL]) versus 1,185 μmol/L (787 μmol/L) (13.4 mg/dL [8.9 mg/d]) (P=0.96) in each group, respectively, though BUN at the time of hospital admission was significantly higher for acute renal failure foals (P=0.009). In the spurious group, serum creatinine at admission decreased to 504 μmol/L (380 μmol/L) (5.7 mg/dL [4.3 mg/dL]) by 24 hours, and to 159 μmol/L (80 μmol/L) (1.8 mg/dL [0.9 mg/dL]) at 48 hours, and to 115 μmol/L (44 μmol/L) (1.3 mg/dL [0.5 mg/dL]) at 72 hours. Twenty-three of 28 foals with spurious hypercreatininemia survived to hospital discharge and there was no difference in mean admission creatinine between survivors (1176 μmol/L [628 μmol/L]) (13.3 mg/dL [7.1 mg/dL]) and nonsurvivors (1308 μmol/L [857 μmol/L]) (14.8 mg/dL [9.7 mg/dL]) (P=0.67). Twenty of 28 foals had clinical signs suggestive of neonatal encephalopathy. Conclusion – Creatinine decreased by >50% within the initial 24 hours of standard neonatal therapy and was within the reference interval in all but 1 foal within 72 hours of hospitalization. The diagnosis of neonatal encephalopathy was common in these foals.

Use of oseltamivir in the treatment of canine parvoviral enteritis

Abstract: OBJECTIVE: To determine if oseltamivir with standard therapy for canine parvoviral enteritis ameliorates disease morbidity, mortality, or both; to document significant adverse effects associated with its use. DESIGN: Prospective, randomized, blinded, placebo-controlled clinical trial. SETTING: University veterinary teaching hospital. ANIMALS: Thirty-five dogs. INTERVENTIONS: Standard therapy was administered to all dogs. Treatment dogs also received oseltamivir, while control dogs received an equivalent volume of placebo. MEASUREMENTS AND MAIN RESULTS: Dogs were monitored daily according to a clinical scoring system, physical parameters, and diagnostic evaluations. Dogs in the treatment group gained a significant percentage of weight during hospitalization (mean, +2.6%; SD, 7.1%) versus the control dogs (mean, -4.5%; SD, 6.9%) (P=0.006). Treatment dogs did not have any significant changes in their white blood cell (WBC) count, while control dogs experienced a significant drop in their WBC counts during their initial stay. In addition, it did not appear that oseltamivir use was associated with any major adverse clinical effects. CONCLUSIONS: While a clear advantage to the use of oseltamivir was not established, a significant weight loss during hospitalization, as well as a significant decrease in WBC count were documented in the control group. No major adverse effects were identified that could be associated with oseltamivir administration. Based on these results, the true role of oseltamivir in the treatment of parvoviral enteritis remains speculative, although it is believed that further investigation is warranted.

Thromboelastography in healthy horses and horses with inflammatory gastrointestinal disorders and suspected coagulopathies.

Abstract: Objectives – To evaluate the use of citrated recalcified (nonactivated) thromboelastography (TEG) in healthy horses and horses with colitis and suspected coagulopathies. Design – Prospective, observational study conducted between October 2007 and June 2009. Setting – Veterinary Teaching Hospital. Animals – Forty-five healthy adult horses and 12 sick adult horses with colitis and prolonged prothrombin time (PT) or activated partial thromboplastin time (aPTT). Interventions – None. Measurements and Main Results – Whole blood was collected on admission. Coagulation profile (PT, aPTT, platelet count, and fibrinogen concentration) and citrated recalcified whole blood TEG analysis (R-time [R], Ktime [K], angle [a], maximum amplitude [MA], G value [G], lysis at 60min [LY60]) were evaluated. Mean values (SD) for TEG parameters in healthy horses were: R 510.4 (3.1) minutes; K 53.5 (1.2) minutes; a 546.3 (11.0)1 ;M A555.6 (5.1)mm; G 56,429 (1,341)dyn/cm 2 , and LY60 55.1 (2.4)%. Mean coefficients of variation for intra-assay/interindividual variability in healthy horses were: R 54.7%/30.7%, K 54.8%/35.3%, a 54.4%/23.8%, MA 51.4%/9.3%, G 53.4%/20.8%, and LY60 513.1%/47.7%, respectively. Horses with colitis and prolonged PT and/or aPTT had longer mean values for R (Po0.001) and K (Po0.001), narrower mean a (Po0.001), decreased mean MA (P 50.001), and smaller mean G (P 50.02); changes consistent with hypocoagulability. Conclusions – Citrated recalcified (nonactivated) TEG demonstrated changes consistent with hypocoagulability in horses with colitis that had preidentified coagulation abnormalities. This technique has high interindividual variability and low intra-assay variability. TEG may be useful for detecting hypocoagulable states in horses with colitis and suspected coagulopathies.

The effect of unfractionated heparin on thrombelastographic analysis in healthy dogs.

Abstract: Objective – To determine the effect of single and multiple doses of SQ heparin (200 U/kg) on the thrombelastogram of healthy dogs. Design – Prospective study. Setting – University research facility. Animals – Six random-source female dogs. Interventions – Baseline parameters, including a CBC with platelet count, prothrombin time, activated partial thromboplastin time (aPTT), and antithrombin were performed. Thrombelastography (TEG) and aPTT were performed hourly for 12 hours after unfractionated heparin dosing (200 U/kg, SQ). Anti-Xa activity was assayed at 0, 3, 6, and 8 hours. Heparin was then administered every 8 hours for 3 days. The sampling protocol on Day 4 was identical to Day 1. Measurements and Main Results – On Day 1, percentage change from baseline for TEG parameter R, as well as absolute values of K, angle, and maximum amplitude (MA) were evaluated. Statistically significant (P<0.01) prolongation of the R time and a decrease in angle and MA was seen in all dogs by hour 3. R and MA were unmeasurable for most dogs between 3 and 5 hours. All TEG tracings returned to baseline by 12 hours. Day 4 TEG tracings mimicked those on Day 1. Only 1 dog achieved aPTT values outside the reference interval on both days. Anti-Xa activity levels increased on Day 4 but not on Day 1. Based on post hoc in vitro analysis, prolongation of R time occurred at plasma heparin levels as low as 0.075 U/mL, well below the lower limit of detection of the anti-Xa activity level assay. Conclusions – Administration of SQ heparin results in progressive changes in the TEG tracing, with maximal change occurring 3–5 hours after dosing. The extensive prolongation of the R time also indicates that TEG may be too sensitive and limits its utility as a monitoring tool for unfractionated heparin therapy.

Safety and efficacy of high-dose fomepizole compared with ethanol as therapy for ethylene glycol intoxication in cats.

Abstract: Objective – To determine the safety and efficacy of high-dose fomepizole compared with ethanol (EtOH) in cats with ethylene glycol (EG) toxicosis. Design – Prospective study. Setting – University veterinary research laboratory. Animals – Thirteen cats. Interventions – Two cats received injections of high-dose fomepizole (Study 1). Three cats received lethal doses of EG and fomepizole treatment was initiated 1, 2, or 3 hours later (Study 2). Eight cats received a lethal dose of EG and were treated with fomepizole or EtOH (Study 3). Cats treated with fomepizole received 125 mg/kg IV initially, then 31.25 mg/kg at 12, 24, and 36 hours. Cats treated with EtOH received 5 mL of 20% EtOH/kg IV initially, then every 6 hours for 5 treatments, then every 8 hours for 4 treatments. Cats also received fluids and supportive therapy as needed. Measurements and Main Results – Clinical signs were monitored and serial blood analyses performed. Cats receiving fomepizole experienced mild sedation but no biochemical evidence of toxicity. Cats receiving fomepizole for EG intoxication survived if therapy was initiated within 3 hours of EG ingestion. One of the 6 developed acute renal failure (ARF) but survived. Only 1 of the 3 cats treated with EtOH 3 hours following EG ingestion survived; 2 developed ARF and were euthanized. Cats treated 4 hours following EG ingestion developed ARF, whether treated with EtOH or fomepizole. Conclusions – Fomepizole is safe when administered to cats in high doses, prevents EG-induced fatal ARF when therapy is instituted within 3 hours of EG ingestion, and is more effective than treatment with EtOH.

Continuous positive airway pressure administered via face mask in tranquilized dogs.

Abstract: Objective – To evaluate the tolerance of a continuous positive airway pressure (CPAP) mask in tranquilized dogs and compare PaO2 in arterial blood in dogs receiving oxygen with a regular face mask or CPAP mask set to maintain a pressure of 2.5 or 5 cm H2O. Design – Prospective, randomized clinical study. Setting – University teaching hospital. Animals – Sixteen client-owned dogs without evidence of cardiopulmonary disease were studied. Interventions – Eight animals were randomly assigned to each of 2 treatment groups: group A received 2.5 cm H2O CPAP and group B received 5 cm H2O CPAP after first receiving oxygen (5 L/min) by a regular face mask. Animals were tranquilized with acepromazine 0.05 mg/kg, IV and morphine 0.2 mg/kg, IM. An arterial catheter was then placed to facilitate blood sampling for pHa, PaO2, and PaCO2 determinations before and after treatments. Direct mean arterial pressure, heart rate, respiratory rate, and temperature were also recorded after each treatment. Measurements and Main Results – CPAP administration was well tolerated by all animals. The mean arterial pressure, heart rate, respiratory rate, temperature, PaCO2, and pHa, did not differ at any time point between groups. Differences were seen in oxygenation; in group A, PaO2 significantly increased from a mean of 288.3±47.5 mm Hg with a standard mask to a mean of 390.3±65.5 mm Hg with the CPAP mask and in group B, PaO2 increased similarly from 325.0±70.5 to 425.2±63.4 mm Hg (P<0.05); no differences were detected between the 2 CPAP treatments. Conclusions – In healthy tranquilized dogs noninvasive CPAP is well tolerated and increases PaO2 above values obtained when using a regular face mask.

Use of a nanocrystalline silver dressing and vacuum-assisted closure in a severely burned dog.

Abstract: Objective – To describe the first veterinary use of a nanocrystalline silver dressing (NSD) and use of vacuum-assisted closure (VAC) to treat a severely burned dog. Case or Series Summary – A 1-year-old female intact American Staffordshire Terrier with 50% total body surface area burned was referred for definitive care approximately 18–24 hours post injury. The dog was treated with crystalloid fluids, hydroxyethyl starch, and antimicrobials based on culture and sensitivity results of wound cultures, fresh frozen plasma, human serum albumin, and packed red cells. Wound care initially consisted of daily debridement under anesthesia with silver sulfadiazine application and bandaging. Because of the extent and the location of the wounds and morbid state of the patient, early wound grafting was not an option. Because of its reported improvement in granulation tissue formation and decreased tissue edema, VAC was used once the majority of burned tissue was manually debrided. Because of the pain caused by VAC and traditional bandaging techniques with this extent of injury, an NSD was utilized. This strategy was chosen due to the antimicrobial properties of NSD and the reduced necessity for daily bandage changes, which was reduced to only every 3 days. This protocol reduced the need for daily sedation or anesthesia. New or Unique Information Provided – VAC and NSD were used successfully for the treatment of a severe burn injury in a dog. The use of NSD decreased the cost of therapy by reducing the need for daily bandage changes, thereby reducing the anesthetic and analgesic costs and allowing the patient to be managed on an outpatient basis.

Continuous versus intermittent delivery of nutrition via nasoenteric feeding tubes in hospitalized canine and feline patients: 91 patients (2002-2007).

Abstract: Objective – To compare continuous to intermittent feeding at delivering prescribed nutrition in hospitalized canine and feline patients. Design – Retrospective clinical study. Setting – University teaching hospital. Animals – Fifty-four cats and 37 dogs. Measurements and Main Results – Twenty-four-hour periods of prescribed and delivered nutrition (kcal) were recorded, and the percentage of prescribed nutrition delivered (PPND) was calculated. If the patient received nasoenteric feeding for >1 day, then the average PPND per day was calculated. Frequency of gastrointestinal complications (vomiting, diarrhea, and regurgitation) was calculated per patient for each group. The PPND was not significantly different between patients fed continuously (99.0%) and patients fed intermittently (92.9%). Vomiting affected 29% of patients (26/91), diarrhea affected 26% of patients (24/91), and regurgitation affected 5% of patients (5/91). There was no significant difference in incidence of gastrointestinal complications between the patients fed continuously and the patients fed intermittently. There was a significantly higher incidence of diarrhea and regurgitation in dogs than in cats. Conclusions – PPND was not significantly different for continuous versus intermittent feeding via nasoenteric tubes. Frequencies of gastrointestinal complications were not significantly different between patients fed continuously and patients fed intermittently. Enterally fed dogs had a significantly higher frequency of regurgitation and diarrhea than enterally fed cats. Prospective studies are warranted to investigate causes for these potential inter-species differences.