Summary Reasons for performing study: Blood lactate concentration has been shown to be a useful clinical indicator in human patients, but has not been formally investigated in critically ill foals. Objective: To investigate the association of blood lactate with hospital survival, markers of cardiovascular status, metabolic acid base status, sepsis and systemic inflammatory response syndrome (SIRS). Methods: A database containing clinical, haematological, plasma biochemical and hospital outcome data on neonatal foals referred to an intensive care unit in 2000‐2001 was analysed. Seventy‐two foals for which arterial lactate was measured at admission were included in the study. Results: Sixty‐one foals had an admission lactate concentration >2.5 mmol/1. Admission lactate was statistically associated with hospital survival, mean arterial pressure, blood creatinine concentration, bacteraemia, anion gap, lactate concentration at 18‐36 h after admission and evidence of SIRS, but not with packed cell volume or heart rate. Lactate at 18‐36 h was also associated with survival and evidence of SIRS. Anion gap, base excess, base excess due to unidentified anions (BEua), simplified strong ion gap or bicarbonate correctly classified foals for presence of hyperlactaemia (>5 mmol/1) in 80% of animals. Conclusions: Admission blood lactate gives important prognostic information. Lactate should be measured rather than assumed from the anion gap, base excess, BEua, simplified strong ion gap or bicarbonate. Potential relevance: Blood lactate concentrations at admission are clinically relevant in neonatal foals and warrant further investigation. This should include the clinical value of measuring changes in lactate in response to treatment.

Reasons for Performing Study: Critical illness is associated with hyperglycemia in humans, and a greater degree and duration of hyperglycemia is associated with nonsurvival. Hypoglycemia is also seen in critically ill humans, and is associated with nonsurvival. This might also be true in the critically ill foal.Objectives: To investigate the association of blood glucose concentrations with survival, sepsis, and the systemic inflammatory response syndrome (SIRS).Methods: Blood glucose concentrations at admission (515 foals) and 24 hours (159 foals), 36 hours (95), 48 hours (82), and 60 hours (45) after admission were analyzed. Logistic regression analyses were performed to investigate the association of glucose concentrations with survival, sepsis, a positive blood culture, or SIRS.Results: 29.1% of foals had blood glucose concentrations within the reference range (76-131 mg/dL) at admission, 36.5% were hyperglycemic, and 34.4% were hypoglycaemic. Foals that did not survive to hospital discharge had lower mean blood glucose concentrations at admission, as well as higher maximum and lower minimum blood glucose concentrations in the 1st 24 hours of hospitalization, and higher blood glucose at 24 and 36 hours. Foals with blood glucose concentrations o2.8 mmol/L (50 mg/dL) or 410 mmol/L (180 mg/dL) at admission were less likely to survive. Hypoglycemia at admission was associated with sepsis, a positive blood culture, and SIRS.Conclusions and Potential Relevance: Derangements of blood glucose concentration are common in critically ill foals. Controlling blood glucose concentrations may therefore be beneficial in the critically ill neonatal foal, and this warrants further investigation.

Equine protozoal myeloencephalitis (EPM) is a serious disease of horses, and its management continues to be a challenge for veterinarians. The protozoan Sarcocystis neurona is most commonly associated with EPM. S. neurona has emerged as a common cause of mortality in marine mammals, especially sea otters (Enhydra lutris). EPM-like illness has also been recorded in several other mammals, including domestic dogs and cats. This paper updates S. neurona and EPM information from the last 15 years on the advances regarding life cycle, molecular biology, epidemiology, clinical signs, diagnosis, treatment and control.

Equine protozoal myeloencephalitis (EPM) remains an important neurologic disease of horses. There are no pathognomonic clinical signs for the disease. Affected horses can have focal or multifocal central nervous system (CNS) disease. EPM can be difficult to diagnose antemortem. It is caused by either of 2 parasites, Sarcocystis neurona and Neospora hughesi, with much less known about N. hughesi. Although risk factors such as transport stress and breed and age correlations have been identified, biologic factors such as genetic predispositions of individual animals, and parasite‐specific factors such as strain differences in virulence, remain largely undetermined. This consensus statement update presents current published knowledge of the parasite biology, host immune response, disease pathogenesis, epidemiology, and risk factors. Importantly, the statement provides recommendations for EPM diagnosis, treatment, and prevention.

Results suggested that various factors were associated with outcome in horses with septic tenosynovitis. However, surgical technique was not found to be associated with survival rate or rate of return to intended use.

Objective: To evaluate the accuracy of a published score designed to predict sepsis in foals in a clinical setting and to evaluate the association of clinical and clinicopathological variables with sepsis. Design: Observational study. Retrospective for data from 1998. Prospective in 1999–2001. Setting: Foal intensive care unit of a university hospital. Animals: Client‐owned foals of less than 10 days of age, presenting from 1998 to 2001. Interventions: None. Measurements and main results: Data from the history and physical examination, together with admission hematology, biochemistry and arterial blood gas analysis were used to generate the published sepsis scores. The same data were investigated for their statistical relationship with sepsis. The presence or absence of sepsis was determined from blood culture, culture of sites of suspected local infection, clinical course and/or post‐mortem examination. The modified sepsis score was calculated for 168 foals, which were classified as septic (86), non‐septic (45) or not possible to classify (37). The modified sepsis score correctly predicted sepsis in 58 out of 86 foals and non‐sepsis in 34 out of 45 foals, resulting in a sensitivity of 67%, a specificity of 76%, a positive predictive value of 84% and a negative predictive value of 55%. Abnormal neutrophil cytology, an immunoglobulin concentration of less than 400 mg/dl, and low blood glucose concentration had the strongest association with sepsis. Conclusions: The low negative predictive value of the sepsis score limited its clinical utility. The sepsis score should not be used to define sepsis in clinical studies, unless previously validated in the study center.

Thirty-two physical examination and laboratory variables were recorded during examination of 165 horses admitted for acute abdominal disease. Univariate analyses were performed to determine which of the variables were significantly different between horses that lived or died. Stepwise logistic regression was performed to identify variables with the best predictive value. Four variables (heart rate, peritoneal fluid total protein concentration, blood lactate concentration, and abnormal mucous membrane) remained significant when entered into the model. Histograms for each significant variable were used to set "cutting-points," establishing categories that were made into a table of assigned values from which a Colic Severity Score (CSS) for each horse was calculated. Seventy-one horses in a second group were used to validate the scoring chart. Case mortality rate was similar in both groups (20.6% in development group versus 21.1% in validation group). All horses with a CSS > 7 died, whereas 75% of those with a score of < or = 7 lived. For the validation group, use of the scoring table yielded a positive predictive value of 100%, negative predictive value of 91.8%, sensitivity of 66.7%, and specificity of 100%. The overall accuracy of the CSS was 93%. The CSS is a rapid and accurate method for predicting survival in cases of equine acute abdominal disease.

Odds of a diagnosis of CVM were greater in young horses and horses of specific breeds. Detection of gait asymmetry and cervical hyperesthesia were frequently reported in association with CVM. Accurate diagnosis of lesions associated with CVM by use of radiography and myelography can be challenging.