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The CPT® Code 84545 refers to the procedure for measuring urea nitrogen clearance, which involves obtaining a blood sample to quantify the total blood urea nitrogen (BUN) level. Urea is a metabolic waste product generated in the liver during the breakdown of proteins, a process that occurs through a series of chemical reactions known as the urea or Krebs-Henseleit cycle. Once produced, urea enters the bloodstream and is subsequently filtered by the kidneys, where it is excreted in the urine. The measurement of BUN is crucial for evaluating renal function, as it provides insights into the kidneys' ability to filter waste from the blood. This test is particularly important for monitoring patients with existing renal disease and assessing the effectiveness of dialysis treatments. Additionally, BUN levels may be evaluated in patients suffering from acute or chronic illnesses that can impact renal function. It is important to note that this specific code, 84545, involves the collection of a urine sample over a 24-hour period, distinguishing it from other related codes such as 84525, which utilizes a reagent strip for urine testing, and 84540, which measures only the BUN without the clearance aspect.
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The procedure associated with CPT® Code 84545 is indicated for several clinical scenarios where assessment of renal function is necessary. The following conditions may warrant the measurement of urea nitrogen clearance:
The procedure for CPT® Code 84545 involves several key steps to ensure accurate measurement of urea nitrogen clearance. The following procedural steps are outlined:
After the completion of the urea nitrogen clearance test, patients may resume their normal activities unless otherwise instructed by their healthcare provider. There are typically no specific post-procedure care requirements; however, patients should be informed about the importance of following up with their healthcare provider to discuss the results of the test. The results will help guide further management of any underlying renal conditions or other health issues that may have been evaluated through this procedure.
| Short Descr | UREA-N CLEARANCE TEST | Medium Descr | UREA NITROGEN CLEARANCE | Long Descr | Urea nitrogen, clearance | Status Code | Statutory Exclusion (from MPFS, may be paid under other methodologies) | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 9 - Not Applicable | Multiple Procedures (51) | 9 - Concept does not apply. | Bilateral Surgery (50) | 9 - Concept does not apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 9 - Concept does not apply. | Co-Surgeons (62) | 9 - Concept does not apply. | Team Surgery (66) | 9 - Concept does not apply. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | CLIA Waived (QW) | No | APC Status Indicator | Conditionally packaged laboratory tests | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | T1H - Lab tests - other (non-Medicare fee schedule) | MUE | 1 | CCS Clinical Classification | 233 - Laboratory - Chemistry and Hematology |
| GW | Service not related to the hospice patient's terminal condition | X2 | Continuous/focused services: for reporting services by clinicians whose expertise is needed for the ongoing management of a chronic disease or a condition that needs to be managed and followed with no planned endpoint to the relationship; reporting clinician service examples include but are not limited to: a rheumatologist taking care of the patient's rheumatoid arthritis longitudinally but not providing general primary care services | 90 | Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd |
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| Pre-1990 | Added | Code added. |
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