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Official Description

Anesthesia complicated by utilization of controlled hypotension (List separately in addition to code for primary anesthesia procedure)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 99135 is utilized to indicate a specific circumstance that complicates the administration of anesthesia during surgical procedures. This code is not intended to be reported independently; rather, it must be used in conjunction with the primary anesthesia procedure codes. The essence of this code lies in its application to situations where controlled hypotension is employed as part of the anesthesia management. Controlled hypotension refers to a deliberate reduction in blood pressure to minimize intraoperative blood loss, thereby enhancing the surgical field visibility and reducing the necessity for blood transfusions. This technique is characterized by a targeted decrease in the patient's mean arterial pressure by approximately 30%, or by lowering the systolic blood pressure to a range of 80-90 mmHg, or the mean arterial pressure to between 50-65 mmHg. Such management is particularly relevant in high-risk surgical environments, including spinal surgery, endoscopic microsurgery of the head, oromaxillofacial surgery, major orthopedic procedures, and cardiovascular surgeries. The use of this code reflects the additional complexities and risks associated with the anesthesia service provided under these specific conditions.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The use of CPT® Code 99135 is indicated in scenarios where controlled hypotension is necessary during surgical procedures. This technique is particularly relevant for the following conditions:

  • Spinal Surgery - Controlled hypotension is often employed to minimize blood loss and enhance the surgical field during spinal operations.
  • Endoscopic Microsurgery on the Head - This approach helps maintain a clear operative field by reducing blood flow in delicate areas.
  • Oromaxillofacial Surgery - In surgeries involving the jaw and facial structures, controlled hypotension aids in visibility and reduces bleeding.
  • Major Orthopedic Surgery - This technique is utilized to manage blood loss during extensive orthopedic procedures.
  • Cardiovascular Surgery - Controlled hypotension is critical in cardiac procedures to optimize surgical conditions and minimize complications.

2. Procedure

The procedural steps associated with the application of controlled hypotension in conjunction with anesthesia are as follows:

  • Step 1: Preoperative Assessment - Prior to the surgical procedure, a thorough evaluation of the patient's medical history and current health status is conducted. This assessment helps determine the appropriateness of controlled hypotension based on the patient's baseline blood pressure and overall cardiovascular health.
  • Step 2: Anesthesia Administration - The primary anesthesia procedure is initiated, which may involve general or regional anesthesia techniques. The anesthesiologist monitors the patient's vital signs closely during this phase.
  • Step 3: Induction of Controlled Hypotension - Once anesthesia is established, the anesthesiologist implements controlled hypotension by adjusting the anesthetic agents and possibly administering vasodilators or other medications to achieve the desired blood pressure targets.
  • Step 4: Continuous Monitoring - Throughout the surgical procedure, the patient's blood pressure and other vital signs are continuously monitored to ensure that the controlled hypotension is maintained within the specified parameters, allowing for timely adjustments as necessary.
  • Step 5: Postoperative Care - After the procedure, the patient is monitored in the recovery area to assess their response to anesthesia and the effects of controlled hypotension. Any complications or concerns are addressed promptly.

3. Post-Procedure

Following the use of controlled hypotension during surgery, patients typically require careful monitoring in the postoperative period. This includes assessing vital signs to ensure that blood pressure returns to baseline levels and that there are no adverse effects from the hypotensive management. Recovery protocols may involve fluid management and pain control, as well as monitoring for any signs of bleeding or complications related to the surgical procedure. The anesthesiologist will provide specific instructions for postoperative care, which may include follow-up appointments to evaluate the patient's recovery and any further interventions if necessary.

Short Descr ANES COMP CTRLD HYPOTENSION
Medium Descr ANES COMP UTILIZATION CONTROLLED HYPOTENSION
Long Descr Anesthesia complicated by utilization of controlled hypotension (List separately in addition to code for primary anesthesia procedure)
Status Code Bundled Code
Global Days ZZZ - Code Related to Another Service
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
APC Status Indicator Code Not Recognized by OPPS when submitted on Outpatient Hospital Part B Bill Type (12x/13x)
Type of Service (TOS) 7 - Anesthesia
Berenson-Eggers TOS (BETOS) P0 - Anesthesia
MUE 0
CCS Clinical Classification 232 - Anesthesia
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.
22 Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m service.
25 Significant, separately identifiable evaluation and management service by the same physician or other qualified health care professional on the same day of the procedure or other service: it may be necessary to indicate that on the day a procedure or service identified by a cpt code was performed, the patient's condition required a significant, separately identifiable e/m service above and beyond the other service provided or beyond the usual preoperative and postoperative care associated with the procedure that was performed. a significant, separately identifiable e/m service is defined or substantiated by documentation that satisfies the relevant criteria for the respective e/m service to be reported (see evaluation and management services guidelines for instructions on determining level of e/m service). the e/m service may be prompted by the symptom or condition for which the procedure and/or service was provided. as such, different diagnoses are not required for reporting of the e/m services on the same date. this circumstance may be reported by adding modifier 25 to the appropriate level of e/m service. note: this modifier is not used to report an e/m service that resulted in a decision to perform surgery. see modifier 57 for significant, separately identifiable non-e/m services, see modifier 59.
95 Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system.
AA Anesthesia services performed personally by anesthesiologist
CR Catastrophe/disaster related
GC This service has been performed in part by a resident under the direction of a teaching physician
GT Via interactive audio and video telecommunication systems
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
LT Left side (used to identify procedures performed on the left side of the body)
Q1 Routine clinical service provided in a clinical research study that is in an approved clinical research study
Q6 Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area
RT Right side (used to identify procedures performed on the right side of the body)
X4 Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
Date
Action
Notes
2024-01-01 Changed Short and Medium Descriptions changed.
Pre-1990 Added Code added.
Code
Description
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