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The CPT® Code 82140 refers to a laboratory test that measures the levels of ammonia in the blood. Ammonia is a waste product that is generated during the metabolism of proteins in the body. Under normal physiological conditions, ammonia is converted into urea by the liver, which is then excreted from the body through the kidneys. However, when the liver is compromised due to conditions such as cirrhosis or hepatitis, the conversion process may be impaired, leading to elevated levels of ammonia in the bloodstream. This condition can manifest with various symptoms, including confusion, tremors, excessive sleepiness, and in severe cases, coma. The ammonia test is particularly relevant in the context of certain disease states, such as Reye's syndrome or liver failure, where monitoring ammonia levels can provide critical information regarding the patient's metabolic status. To perform this test, a blood sample is collected, typically through a venipuncture or an arterial access line, which is a procedure that may need to be reported separately. The collected specimen is then analyzed using colorimetric methods, which involve measuring the intensity of color produced in a chemical reaction to determine the concentration of ammonia in the sample.
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The ammonia blood test is indicated for several clinical scenarios where monitoring ammonia levels is crucial for patient management. The following conditions may warrant this test:
The procedure for measuring ammonia levels in the blood involves several key steps that ensure accurate results. First, a healthcare professional will perform a venipuncture or utilize an arterial access line to obtain a blood sample from the patient. This step is critical as it provides the specimen needed for analysis. The site of the puncture is typically cleaned and prepared to minimize the risk of infection. Once the blood is drawn, it is collected in a suitable container that prevents contamination and preserves the integrity of the sample. After collection, the specimen is transported to the laboratory for analysis. In the lab, the ammonia level is determined using colorimetric methods, which involve adding specific reagents to the blood sample that react with ammonia to produce a color change. The intensity of this color change is then measured, allowing for the quantification of ammonia levels in the sample. It is important to follow proper laboratory protocols to ensure the accuracy and reliability of the test results.
After the ammonia blood test is completed, there are generally no specific post-procedure care requirements for the patient, as the test is minimally invasive. However, patients may be advised to monitor for any unusual symptoms or reactions at the venipuncture site, such as excessive bleeding, swelling, or signs of infection. If the blood sample was taken due to suspected elevated ammonia levels, the healthcare provider will typically discuss the results with the patient and may recommend further evaluation or treatment based on the findings. Continuous monitoring may be necessary for patients with underlying liver conditions to manage their health effectively.
| Short Descr | ASSAY OF AMMONIA | Medium Descr | ASSAY OF AMMONIA | Long Descr | Ammonia | 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. | GW | Service not related to the hospice patient's terminal condition | Q4 | Service for ordering/referring physician qualifies as a service exemption | 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. | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | 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. | 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. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | GC | This service has been performed in part by a resident under the direction of a teaching physician | 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 | Q3 | Live kidney donor surgery and related services | QW | Clia waived test | 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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