The Influence of Preoperative Cardiopulmonary Capacity Mesured in MET's (Metabolic Equivalents) on the Perioperative Lactate Level

The determination of the cardiopulmonary (c/p) capacity is very important for the evaluation of every patient undergoing surgery. The ability to climb at least two flight of stairs is seen to be an acceptable c/p capacity for surgery. There are several ways to evaluate the fitness of patients. A common method to estimate the cardiopulmonary capacity is defining patients through the MET's (metabolic equivalents) scale. MET's can be defined relatively easy through a simple questionnaire. Patients with a reduced c/p capacity have less than 4 MET's, patients with a relatively good c/p capacity have 4-10 MET's and patients with a excellent c/p capacity have more than 10 MET's. The lactate level in blood serum is a common parameter to asses anaerobic metabolism in patients. A high lactate level correlates with higher mortality rates and outcome. To yet it is not clear if there exists a correlation between the preoperative cardiopulmonary capacity measured in MET's and the perioperative lactate level. We hypothysed that patients with a reduced cardiopulmonary capacity are associated with higher perioperative lactate levels, as these group of patients compensate the stressors operation/anesthesia less than patients with a good c/p capacity.