What causes the metabolic acidosis seen in burn resuscitation?

The metabolic acidosis observed during burn resuscitation is primarily caused by increased lactate production. When the body experiences extensive burns, it undergoes a state of stress that leads to tissue hypoxia and impaired perfusion. In these conditions, the cells switch from aerobic metabolism to anaerobic metabolism, which produces lactate as a byproduct. As lactate accumulates in the blood, it contributes to a decrease in blood pH, resulting in metabolic acidosis.

The physiological response to burn injury and the subsequent resuscitation efforts exacerbate this condition, as the aggressive fluid resuscitation can lead to further shifts in electrolytes and acid-base balance. However, the direct cause of the metabolic acidosis primarily links back to the increased lactate production due to hypoxia and cellular stress rather than fluid overload or variations in carbon dioxide levels and sodium levels.