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The CPT® Code 83935 refers to the measurement of osmolality in urine. Osmolality is a critical laboratory test that quantifies the concentration of solutes in a fluid, which in this case is urine. Solutes are substances that dissolve in a liquid, and in urine, these include various particles such as sodium, chloride, potassium, urea, and glucose. The osmolality of urine is indicative of the kidney's ability to concentrate or dilute urine, which is essential for maintaining fluid balance in the body. The testing of osmolality can be performed using two primary methodologies: freezing point depression and vapor pressure osmometry. These methods rely on the principle that the presence of solutes lowers the freezing point of a liquid compared to pure water. A higher concentration of solutes in the urine results in a lower freezing point, which can be measured and reported as osmolality. This test is often performed alongside blood osmolality measurements to provide a comprehensive assessment of a patient's fluid status and kidney function, particularly in cases of suspected electrolyte imbalances or renal impairment.
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The osmolality test for urine (CPT® Code 83935) is indicated for several clinical scenarios, particularly when evaluating a patient's fluid balance and kidney function. The following conditions may warrant this test:
The procedure for measuring urine osmolality (CPT® Code 83935) involves the following steps:
Post-procedure care for urine osmolality testing is minimal, as the test is non-invasive and does not require any specific recovery time. Patients can resume their normal activities immediately after specimen collection. However, it is important for healthcare providers to discuss the results with the patient, explaining any necessary follow-up tests or treatments based on the findings. Additionally, if the urine osmolality results indicate abnormal levels, further evaluation may be warranted to determine the underlying cause and appropriate management strategies.
| Short Descr | ASSAY OF URINE OSMOLALITY | Medium Descr | ASSAY OF OSMOLALITY URINE | Long Descr | Osmolality; urine | 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. | 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. | 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. | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | 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. | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | GW | Service not related to the hospice patient's terminal condition | 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 | GZ | Item or service expected to be denied as not reasonable and necessary | 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 | 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. |
| 2011-01-01 | Changed | Guideline information changed. |
| Pre-1990 | Added | Code added. |
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