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Official Description

pH; body fluid, not otherwise specified

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 83986 refers to the measurement of pH in body fluids that are not otherwise specified. pH is a crucial indicator of the acidity or alkalinity of a substance, determined by the concentration of hydrogen ions (H+) present. This measurement is essential in various clinical settings as it helps assess the acid-base balance of the fluid being tested. A pH level that is lower than the normal range suggests that the specimen is too acidic, a condition known as acidosis, while a higher pH level indicates that the specimen is too alkaline, referred to as alkalosis. This code is specifically utilized when there is no more specific code available for the type of body fluid being analyzed, such as urine, vaginal fluid, or cerebrospinal fluid. The methodology for conducting this test may vary depending on the type of body fluid and can include the use of pH reagents, meters, or electrodes to obtain accurate readings. It is important to note that for the pH measurement of exhaled breath condensate, a different code, CPT® 83987, is used, which is specifically designed to assist in diagnosing inflammatory lung diseases and evaluating treatment responses. In this case, a specialized device collects exhaled air, allowing for the condensation of moisture, which is then analyzed for pH levels.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The pH measurement of body fluids is performed for various clinical indications, particularly when assessing the acid-base balance of a specimen. The following conditions may warrant the use of CPT® Code 83986:

  • Acidosis A condition characterized by an excess of hydrogen ions, leading to a lower than normal pH level in the body fluid.
  • Alkalosis A condition where there is a deficiency of hydrogen ions, resulting in a higher than normal pH level in the body fluid.
  • Fluid Analysis When specific body fluids such as urine, vaginal fluid, or cerebrospinal fluid are analyzed for their pH levels to aid in diagnosis or treatment monitoring.

2. Procedure

The procedure for measuring the pH of body fluids involves several key steps, which are outlined as follows:

  • Step 1: Sample Collection The first step in the procedure is the collection of the body fluid sample. This may involve drawing blood, collecting urine, or obtaining other bodily fluids, depending on the specific type of analysis required.
  • Step 2: Preparation of the Sample Once the sample is collected, it may need to be prepared for testing. This could involve filtering or diluting the fluid to ensure accurate pH measurement.
  • Step 3: pH Measurement The pH of the prepared sample is then measured using appropriate methodologies. This may include the use of pH reagents, meters, or electrodes, which provide a quantitative assessment of the acid-base balance in the fluid.
  • Step 4: Interpretation of Results After obtaining the pH measurement, the results are interpreted in the context of the patient's clinical condition. A pH level outside the normal range may indicate underlying health issues that require further investigation or intervention.

3. Post-Procedure

Post-procedure care following the pH measurement of body fluids typically involves monitoring the patient for any immediate reactions, especially if the sample was obtained through invasive means. The results of the pH test should be documented in the patient's medical record, and any abnormal findings should be communicated to the healthcare provider for further evaluation and management. Depending on the results, additional tests or treatments may be necessary to address any identified acid-base imbalances.

Short Descr ASSAY PH BODY FLUID NOS
Medium Descr PH BODY FLUID NOT ELSEWHERE SPECIFIED
Long Descr pH; body fluid, not otherwise specified
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) Yes
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
QW Clia waived test
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.
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.
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
GA Waiver of liability statement issued as required by payer policy, individual case
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.
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.
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.
FP Service provided as part of family planning program
GC This service has been performed in part by a resident under the direction of a teaching physician
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
GZ Item or service expected to be denied as not reasonable and necessary
HN Bachelors degree level
LT Left side (used to identify procedures performed on the left side of the body)
Q3 Live kidney donor surgery and related services
Q4 Service for ordering/referring physician qualifies as a service exemption
RT Right side (used to identify procedures performed on the right side of the body)
SA Nurse practitioner rendering service in collaboration with a physician
X3 Episodic/broad services: for reporting services by clinicians who have broad responsibility for the comprehensive needs of the patient that is limited to a defined period and circumstance such as a hospitalization; reporting clinician service examples include but are not limited to the hospitalist's services rendered providing comprehensive and general care to a patient while admitted to the hospital
Date
Action
Notes
2011-01-01 Changed Short description changed.
2010-01-01 Changed Code description changed.
Pre-1990 Added Code added.
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