Interpreting lactate measurement in critically ill horses: diagnosis, treatment, and prognosis.

This research focuses on how measuring the lactate levels in horses can help assess their health status, guide treatment methods, and predict prognosis. Particularly, it investigates its use in identifying bacterial infections, diagnosing intestinal strangulation, guiding fluid therapy, and assessing transfusion needs.

Role of Lactate Measurement in Horse Health

• The study suggests that hypovolemia, a state of decreased blood volume, often leads to a decrease in tissue perfusion in horses resulting in hyperlactatemia. As such, assessing blood lactate concentration can help determine horses with hypovolemia and guide corresponding fluid therapy.
• Blood lactate concentration measurement can also be used to evaluate the need for blood transfusion in horses and assess the adequacy of the transfusions they are receiving.

Lactate Measurement as a Diagnostic Tool for Infections

• Sometimes, horses may have a buildup of white blood cells (leukocytes) in closed body cavities. As these cells consume glucose and produce lactate, it becomes crucial to measure the lactate concentration within these cavities to diagnose certain conditions.
• Joint with blood lactate concentration, the measurement of lactate concentration in peritoneal, pleural, or synovial fluid is employed to distinguish septic from nonseptic effusions, conditions where unwanted fluid builds up. In this regard, when the fluid lactate concentration is higher than the blood lactate concentration, it indicates bacterial causes behind the accumulation of that fluid.

Identifying Intestinal Conditions in Horses Using Lactate Concentration

• Particular gastrointestinal issues like intestinal strangulation and ischemia in horses can also be identified using lactate concentration. For horses evaluated for colic, a peritoneal lactate concentration higher than the simultaneously measured blood lactate concentration typically indicates these conditions.

Lactate Measurement as a Prognostic Indicator

• The research suggests that serial blood lactate measurements could potentially serve as a better prognostic indicator than a single lactate measurement.
• In adult horses or foals who had to be hospitalized, the study notes that blood lactate concentration persistently tended to be higher for nonsurvivors compared to survivors. However, these differences were usually subtle.
• Focusing on the rate at which lactate concentrations return to normal rather than single measurements could also be helpful in evaluating horse health, but this proposal would need further investigation.