What is the relationship between Lactated Ringer's (Lactated Ringer's solution) solution and lactic acid levels in blood?

From the Guidelines

Lactated Ringer's solution does not increase blood lactic acid levels in patients with normal liver function. Lactated Ringer's contains sodium lactate (28 mEq/L), which is metabolized by the liver into bicarbonate, actually helping to correct acidosis rather than causing it 1. The lactate in this solution is different from the lactic acid produced during anaerobic metabolism in the body. When administered, the sodium lactate is quickly converted to sodium bicarbonate, typically within 1-2 hours in patients with normal hepatic function. This conversion helps restore normal pH and improves acid-base balance.

Key Points to Consider

• The use of Lactated Ringer's solution is recommended as the first-line balanced fluid resuscitation solution for burns victims, as it is associated with a lower risk of hyperchloraemia and metabolic acidosis compared to 0.9% NaCl 1.
• However, in patients with severe liver dysfunction, the metabolism of lactate may be impaired, potentially leading to lactate accumulation, and normal saline might be preferred over Lactated Ringer's in these cases.
• Elevated lactic acid levels in blood typically result from tissue hypoxia and anaerobic metabolism rather than from Lactated Ringer's administration.
• Current evidence does not support a clear benefit of Ringer’s lactate solution compared to normal saline for important outcomes, such as organ failure, necrosis, or mortality in patients with acute pancreatitis 2.

Clinical Implications

• The choice of fluid resuscitation should be based on the individual patient's needs and underlying conditions.
• Lactated Ringer's solution can be a suitable choice for patients with normal liver function, but alternative fluids may be preferred in patients with severe liver disease or lactic acidosis.
• Further research is needed to determine the optimal fluid therapy practice in various clinical settings, including acute pancreatitis 2.

From the Research

Lactated Ringer's Solution and Lactic Acid in Blood

• Lactated Ringer's solution is a type of fluid resuscitation that contains lactate, which can be metabolized by the body to produce bicarbonate and help correct acidosis 3, 4.
• Lactic acidosis is a condition characterized by elevated levels of lactate in the blood, which can be caused by tissue hypoxia, sepsis, or other conditions 5, 6.
• The presence of elevated lactate levels in critically ill patients has important implications for morbidity and mortality, and lactate measurement can be a useful tool for assessing the severity of illness and guiding treatment 5, 7.
• Studies have shown that lactated Ringer's solution may be associated with improved outcomes in patients with sepsis-induced hypotension, including reduced mortality and improved hospital-free days 3.
• Additionally, lactated Ringer's solution has been shown to be effective in reducing the progression to moderate-to-severe acute pancreatitis, with benefits including a shorter hospital stay and reduced ICU admission rate 4.

Lactic Acid Metabolism

• Lactate is an intermediate in carbohydrate and nonessential amino acid metabolism, and can be considered a waste product for one cell but a useful substrate for another 5.
• The metabolism of lactate is complex, and elevated lactate levels can be caused by a variety of factors, including tissue hypoxia, sepsis, and type B lactic acidosis 5, 6.
• Lactate measurement can be a useful tool for assessing the severity of illness and guiding treatment, but it is important to consider the clinical context and other factors that may influence lactate levels 7.

Clinical Implications

• The use of lactated Ringer's solution as a fluid resuscitation may have implications for patients with elevated lactate levels, as it can help to correct acidosis and improve outcomes 3, 4.
• However, it is important to consider the individual patient's needs and clinical context, as well as the potential risks and benefits of using lactated Ringer's solution 3, 4.
• Further research is needed to fully understand the effects of lactated Ringer's solution on lactate metabolism and clinical outcomes in different patient populations 3, 4.