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The CPT® Code 83930 refers to the measurement of osmolality in blood, which is a critical laboratory test used to assess the concentration of solutes in the blood plasma or serum. Osmolality is defined as the total number of osmotically active particles present in a solution, which in the context of blood includes key solutes such as sodium, chloride, potassium, urea, and glucose. The measurement of osmolality is essential for understanding various physiological and pathological conditions. The testing is typically performed using either freezing point depression methodology or a vapor pressure osmometer, both of which are reliable techniques for determining the concentration of solutes. In clinical practice, a blood specimen for osmolality testing is obtained through a procedure known as venipuncture, which is separately reportable. The results of blood osmolality testing are particularly valuable in diagnosing and managing conditions such as hyponatremia, where there are low sodium levels in the blood, as well as in identifying the presence of toxins and monitoring the effectiveness of certain drug therapies. Additionally, osmolality testing can be performed on urine specimens, as indicated by CPT® Code 83935, to evaluate fluid balance and kidney function. Often, both blood and urine osmolality measurements are conducted to analyze the ratio of urine osmolality to serum osmolality, providing further insights into a patient's hydration status and renal concentrating ability.
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Hyponatremia The osmolality of blood is tested to investigate low levels of sodium in the blood, a condition known as hyponatremia.
Toxin Identification Blood osmolality testing is utilized to identify the presence of toxins in the bloodstream.
Drug Therapy Monitoring This test is also performed to monitor the effectiveness of certain drug therapies that may affect solute concentrations in the blood.
Specimen Collection A blood specimen is obtained through a procedure known as venipuncture. This involves the insertion of a needle into a vein to collect blood for analysis. The blood sample is then processed to measure the osmolality, which reflects the concentration of solutes in the plasma or serum.
Testing Methodology The osmolality of the collected blood sample is measured using either freezing point depression methodology or a vapor pressure osmometer. These methods are designed to accurately determine the concentration of osmotically active particles in the blood, which is crucial for diagnosing various medical conditions.
Result Interpretation Once the osmolality is measured, the results are interpreted in the context of the patient's clinical condition. Elevated osmolality may indicate dehydration or the presence of certain toxins, while low osmolality may suggest overhydration or other underlying health issues.
After the blood specimen is collected and the osmolality test is performed, there are generally no specific post-procedure care requirements for the patient. However, it is important for healthcare providers to monitor the patient’s overall condition and any symptoms that may arise. The results of the osmolality test should be reviewed in conjunction with other clinical findings to guide further diagnostic and therapeutic decisions. If the test indicates abnormal osmolality levels, additional tests or interventions may be warranted to address the underlying cause.
| Short Descr | ASSAY OF BLOOD OSMOLALITY | Medium Descr | ASSAY OF OSMOLALITY BLOOD | Long Descr | Osmolality; blood | 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 | 2 | CCS Clinical Classification | 233 - Laboratory - Chemistry and Hematology |
| 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. | 26 | Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number. | GZ | Item or service expected to be denied as not reasonable and necessary | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | 91 | Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient. | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | GA | Waiver of liability statement issued as required by payer policy, individual case | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | GW | Service not related to the hospice patient's terminal condition | GY | Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | Q4 | Service for ordering/referring physician qualifies as a service exemption | QJ | Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b) | X5 | Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter |
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| Pre-1990 | Added | Code added. |
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