The Renal Function Test without Urine Routine (RFT) is a panel of blood tests designed to evaluate the performance of the kidneys in filtering waste products from the bloodstream and regulating electrolyte balance. This panel typically includes measurements of serum creatinine, blood urea nitrogen (BUN), and electrolytes such as sodium, potassium, and chloride. Creatinine is a waste product produced by muscles at a relatively constant rate and is filtered out of the blood by the kidneys. Elevated levels of creatinine in the blood can indicate impaired kidney function. Blood urea nitrogen (BUN) is a waste product generated from the breakdown of proteins in the liver. Like creatinine, elevated BUN levels may indicate reduced kidney function. Electrolytes play crucial roles in maintaining fluid balance, acid-base balance, and nerve and muscle function. Abnormal levels of electrolytes in the blood can signify kidney dysfunction or other underlying health issues.