What are the Lytes (Electrolyte) criteria?

From the Guidelines

Lytes criteria are not a widely recognized medical term, however, it is likely referring to the criteria for evaluating electrolyte imbalances, such as hypokalemia, which is defined as a potassium level less than 3.5 mEq/L 1.

Definition and Classification

Electrolyte disorders are common among hospitalized patients, with a cumulative incidence of up to 65% reported, especially among critically ill patients 1. The most commonly reported electrolyte disorders are hyponatremia, hyperkalemia, hyperphosphatemia, hypocalcemia, and hypokalemia.

• Hypokalemia is often the result of diuresis, but it may also result from the administration of potassium-free intravenous fluids, potassium loss from vomiting and diarrhea, and other endocrine and renal mechanisms 1.
• Hypophosphatemia, defined as serum phosphate levels <0.81 mmol/l, has a reported prevalence up to 60-80% among ICU patients and is associated with a global negative impact on patients’ outcome 1.

Monitoring and Prevention

Electrolytes abnormalities, including hypokalemia, hypophosphatemia, and hypomagnesemia, should be closely monitored in patients with acute or chronic kidney disease, especially those undergoing kidney replacement therapy (KRT) 1.

• Dialysis solutions containing potassium, phosphate, and magnesium should be used to prevent electrolyte disorders during KRT 1.
• The adoption of phosphate-containing KRT solutions has been reported as a safe and effective strategy to prevent CKRT-related hypophosphatemia, limiting the need for exogenous supplementations 1.
• The use of dialysis and replacement fluids with increased magnesium concentration may be indicated to prevent KRT-related hypomagnesemia 1.

From the Research

Lytes Criteria

• The Lytes criteria are not explicitly mentioned in the provided studies, however, the RIFLE criteria are mentioned in study 2 as a classification system for acute kidney injury (AKI) based on changes in serum creatinine or urine output.
• The RIFLE criteria define AKI as a change from baseline serum creatinine or urine output, with different levels of renal dysfunction classified as Risk, Injury, Failure, Loss, or End-stage kidney disease.
• Study 3 mentions the KDIGO criteria, which define AKI as an increase in serum creatinine levels by at least 0.3 mg/dl within 48 hours or 1.5-fold the baseline, or urine volume less than 0.5 ml/kg/hour for at least 6 hours.
• The KDIGO criteria are used to classify the severity of AKI, with different stages corresponding to different levels of renal dysfunction.
• Studies 4, 5, and 6 discuss the diagnosis, management, and prognosis of AKI, but do not specifically mention the Lytes criteria.

Acute Kidney Injury Classification

• The RIFLE criteria, mentioned in study 2, classify AKI into five categories: Risk, Injury, Failure, Loss, or End-stage kidney disease.
• The KDIGO criteria, mentioned in study 3, classify AKI into three stages based on serum creatinine levels and urine output.
• Study 4 uses the AKIN (Acute Kidney Injury Network) criteria to classify AKI, which is similar to the RIFLE criteria.
• Study 5 discusses the classification of AKI based on urine output and elevations in creatinine level, but does not specify a particular classification system.
• Study 6 does not discuss AKI classification systems in detail, but mentions the importance of serum sodium and potassium levels in predicting survival among critically ill patients with AKI.