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Official Description

Insertion of phrenic nerve stimulator system (pulse generator and stimulating lead[s]), including vessel catheterization, all imaging guidance, and pulse generator initial analysis with diagnostic mode activation, when performed

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The procedure described by CPT® Code 33276 involves the insertion of a phrenic nerve stimulator system, which is designed to assist patients suffering from moderate to severe central sleep apnea (CSA). CSA is a condition characterized by the temporary cessation of breathing due to the brain's failure to send signals to the muscles responsible for respiration. This can occur due to various factors, including cardiovascular disease, stroke, conditions affecting the neck or brainstem, morbid obesity, and the use of narcotics. The phrenic nerve stimulator system aims to restore normal breathing patterns by stimulating the diaphragm to contract, thereby maintaining rhythmic breathing during sleep.

The neurostimulator system consists of an implantable pulse generator (IPG) and stimulating leads. The IPG is typically implanted in a subcutaneous pocket located in the pectoral region, usually on the right side of the body. The stimulating lead is positioned in either the right brachiocephalic vein or the left pericardiophrenic vein (PPV), with the latter being the preferred site. In some cases, a pressure-sensing lead may also be placed in the azygos vein to monitor respiratory activity. The procedure is performed under conscious sedation, allowing the patient to communicate with the physician throughout the process. This careful approach ensures that the placement of the leads is accurate and minimizes the risk of complications.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The insertion of a phrenic nerve stimulator system is indicated for patients diagnosed with moderate to severe central sleep apnea (CSA). This condition is characterized by the brain's intermittent failure to signal the muscles that control breathing, leading to disrupted sleep and potential health complications. The following conditions may contribute to the development of CSA:

  • Cardiovascular Disease - Conditions affecting the heart and blood vessels that may impact respiratory function.
  • Stroke - Neurological events that can impair the brain's ability to regulate breathing.
  • Conditions Affecting the Neck or Brainstem - Anatomical or pathological issues that interfere with the neural pathways responsible for respiration.
  • Morbid Obesity - Excess body weight that can lead to respiratory difficulties and sleep apnea.
  • Narcotic Use - The use of opioid medications that may depress the respiratory system.

2. Procedure

The procedure for inserting a phrenic nerve stimulator system involves several detailed steps to ensure proper placement and functionality of the device. The process begins with the patient receiving conscious sedation, allowing for communication with the physician during the procedure.

  • Step 1: Access to the right side venous system is achieved through a small incision in either the cephalic or subclavian vein. A sheath is placed to facilitate access.
  • Step 2: Two long access wires are advanced into the vena cava, followed by the delivery of a guide catheter over one of the access wires into the superior vena cava. The catheter is then advanced into the left brachiocephalic vein (LBC), positioning the tip at the left subclavian junction.
  • Step 3: Contrast is used to identify venous branches, and an inner catheter is threaded into the guide catheter, extending beyond it. The opening of the left pericardiophrenic vein (PPV) is visualized and accessed using a coronary guidewire while the patient is instructed to take deep breaths to aid in advancement.
  • Step 4: The guide catheter is advanced, and the inner catheter is removed. The stimulation lead is then loaded and deployed through the guide catheter to the target location, ensuring that surrounding vessels are not damaged.
  • Step 5: If placement in the left pericardiophrenic vein is not feasible, the guide catheter is exchanged for a short introducer sheath in the right subclavian vein, allowing for the placement of an alternate lead into the right brachiocephalic vein via transvenous implantation.
  • Step 6: Once the lead is in position, stimulation is tested using a system analyzer, and patient feedback is obtained. Any necessary repositioning is performed, and the lead is stabilized with sutures before being connected to the pulse generator.
  • Step 7: The need for a sensing lead is assessed. If required, a coronary sinus right guide catheter is threaded over the second venous access wire to a location between the tracheal carina and the junction of the brachiocephalic veins.
  • Step 8: The opening of the azygos vein is visualized with contrast, and a wire is advanced to the diaphragm level, facilitated by the patient taking deep breaths or coughing. The inner catheter is advanced over the wire, followed by the guide catheter, which is then advanced to the right lateral branch of the azygos vein for lead deployment.
  • Step 9: The placement of the lead is assessed, and it is tested, stabilized, and connected to the pulse generator, which is implanted in a subcutaneous pocket formed below the clavicle and secured in place.
  • Step 10: Finally, the entire system is checked for proper function to ensure that it will effectively stimulate the phrenic nerve and assist in restoring normal breathing patterns.

3. Post-Procedure

After the insertion of the phrenic nerve stimulator system, patients are typically monitored for any immediate complications related to the procedure. Post-procedure care may include instructions on activity restrictions, wound care, and follow-up appointments to assess the functionality of the device. Patients may also receive guidance on how to operate the stimulator and any necessary adjustments that may be required. The expected recovery period can vary, but patients are generally advised to avoid strenuous activities for a specified duration to allow for proper healing and integration of the device.

Short Descr INSJ PHRNC NRV STIM SYS
Medium Descr INSERTION PHRENIC NERVE STIMULATOR SYSTEM
Long Descr Insertion of phrenic nerve stimulator system (pulse generator and stimulating lead[s]), including vessel catheterization, all imaging guidance, and pulse generator initial analysis with diagnostic mode activation, when performed
Status Code Active Code
Global Days 090 - Major Surgery
PC/TC Indicator (26, TC) 0 - Physician Service Code
Multiple Procedures (51) 2 - Standard payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 1 - Statutory payment restriction for assistants at surgery applies to this procedure...
Co-Surgeons (62) 0 - Co-surgeons not permitted for this procedure.
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Procedure or Service, Not Discounted when Multiple
ASC Payment Indicator Device-intensive procedure added to ASC list in CY 2008 or later; paid at adjusted rate.
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) none
MUE 1

This is a primary code that can be used with these additional add-on codes.

33277 Add On Code Resequenced Code MPFS Status: Active Code APC N ASC N1 Insertion of phrenic nerve stimulator transvenous sensing lead (List separately in addition to code for primary procedure)
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.
78 Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.)
79 Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.)
GC This service has been performed in part by a resident under the direction of a teaching physician
RT Right side (used to identify procedures performed on the right side of the body)
Date
Action
Notes
2024-01-01 Added Code Added.
Code
Description
Code
Description
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