91034

Esophagus, gastroesophageal reflux test; with nasal catheter pH electrode(s) placement, recording, analysis and interpretation

CPT code 91034 describes a comprehensive diagnostic procedure used to evaluate gastroesophageal reflux disease (GERD) by continuously measuring the pH levels within the esophagus over an extended period, typically 24 hours. The procedure involves the placement of a specialized nasal catheter equipped with one or more pH electrodes into the esophagus. This test is a gold standard for quantifying the amount of acid refluxing from the stomach into the esophagus and is critical for diagnosing GERD in patients with atypical symptoms or those unresponsive to empirical medical therapy. It is also an essential preoperative evaluation for patients considering anti-reflux surgery, such as Nissen fundoplication, to confirm the presence of pathological acid exposure. The procedure begins with the patient in a seated position. The nasal passage is anesthetized using a topical anesthetic spray or gel to minimize discomfort. The physician or trained clinician then carefully advances the thin, flexible catheter through the naris, down the nasopharynx, and into the esophagus. The exact positioning of the pH electrode is crucial and is typically placed 5 centimeters above the upper border of the lower esophageal sphincter (LES). Placement can be guided by prior esophageal manometry, which identifies the LES location, or by using fluoroscopy or pH step-up techniques. Once the catheter is correctly positioned, it is secured to the patient's nose and cheek with tape. The catheter is connected to a portable data recorder that the patient wears on a belt or shoulder strap. Over the next 24 hours, the device continuously records esophageal pH levels. The patient is instructed to maintain their normal daily activities, diet, and sleep patterns, and to keep a meticulous diary recording the exact times of meals, episodes of symptoms (such as heartburn, chest pain, or cough), and when they lie down or get up. After the recording period, the patient returns to the clinic, the catheter is removed, and the data from the recorder is downloaded into a computer. The physician then performs a detailed analysis and interpretation of the data, calculating various parameters such as the DeMeester score, the percentage of total time the pH is less than 4, and the correlation between the recorded acid reflux events and the symptoms reported in the patient's diary. This comprehensive assessment allows the physician to definitively diagnose or rule out acid reflux disease and tailor subsequent therapeutic interventions.

Clinical Indications

  • Evaluation of patients with typical GERD symptoms (heartburn, regurgitation) who do not respond to proton pump inhibitor (PPI) therapy.
  • Investigation of atypical or extraesophageal symptoms suspected to be related to GERD, such as chronic cough, asthma, hoarseness, or unexplained chest pain.
  • Preoperative assessment prior to anti-reflux surgery (e.g., Nissen fundoplication) to objectively confirm the presence of pathological acid reflux.
  • Postoperative evaluation in patients who continue to experience reflux symptoms after anti-reflux surgery.
  • Assessment of the efficacy of acid-suppressive medical therapy in patients with complicated or refractory GERD.

Procedure Steps

  1. Prepare the patient by explaining the procedure, obtaining informed consent, and verifying fasting status.
  2. Administer a topical anesthetic spray or gel to the patient's nasal cavity and oropharynx to minimize discomfort.
  3. Determine the appropriate depth for catheter insertion based on prior esophageal manometry or standard anatomical landmarks.
  4. Carefully insert the thin, flexible pH catheter through the anesthetized naris and advance it into the esophagus while instructing the patient to swallow.
  5. Position the pH electrode precisely 5 cm above the upper margin of the lower esophageal sphincter (LES) using manometry data, fluoroscopy, or the pH step-up method.
  6. Secure the proximal end of the catheter to the patient's nose and cheek using hypoallergenic tape to prevent dislodgement.
  7. Connect the catheter to a portable, wearable digital data recorder.
  8. Instruct the patient on maintaining a diary to log meals, symptoms, and changes in body position (upright versus supine) over the 24-hour test period.
  9. Remove the catheter upon the patient's return to the clinic after the continuous 24-hour recording period.
  10. Download the recorded pH data to a computer, calculate the DeMeester score and symptom indices, and generate an interpretive report by the physician.

Coding Guidelines

  • CPT 91034 is a global code that includes catheter placement, continuous recording, and the physician's analysis and interpretation.
  • Use modifier 26 if only the professional component (analysis and interpretation) is provided by the physician.
  • Use modifier TC if only the technical component (equipment, catheter placement, and recording) is provided.
  • Do not report CPT 91034 in conjunction with CPT 91035 (telemetry pH testing) during the same diagnostic session.
  • If multichannel intraluminal impedance (MII) is performed with pH monitoring, report CPT 91037 or 91038 instead of 91034.
  • Esophageal manometry (CPT 91010), if performed solely to locate the LES for pH catheter placement, may be subject to bundling edits depending on payer policies.

Associated ICD-10 Codes