anything done or to be done; anything requiring action or effort; business; concern: an affair of great importance. 2. affairs, matters of commercial or public interest or concern; the transactions of public or private business or finance:
Hyperlactatemia is defined as a persistent, mild to moderate (2-4 mmol/L) increase in blood lactate concentration without metabolic acidosis, whereas lactic acidosis is characterized by persistently increased blood lactate levels (usually >5 mmol/L) in association with metabolic acidosis.
Lactate measured in blood therefore reflects the balance between release from exercising muscles and uptake (by the liver, cardiac muscle and any skeletal muscle fibres which are not themselves under anaerobic stress).