acid reflux test

ac·id re·flux test

a test to detect gastroesophageal reflux by monitoring esophageal pH either basally or after acid is instilled into the stomach, by means of an electrode in the distal esophagus.
Farlex Partner Medical Dictionary © Farlex 2012

acid reflux test

Any of several methods for diagnosing gastroesophageal reflux disease, including endoscopy and direct measurement of esophageal pH.

Patient care

In esophageal pH monitoring, after mild sedation and topical pharyngeal anesthesia, an electrode is placed in the stomach and a reading taken; then the electrode is withdrawn until it is in the esophagus. Normally, the pH will become more alkaline (i.e., rise) as the electrode is moved from the stomach into the esophagus. If there is acid reflux, the pH will be acid in both the stomach and esophagus.

Medical Dictionary, © 2009 Farlex and Partners

Esophageal Manometry

Synonym/acronym: Esophageal function study, esophageal acid study (Tuttle test), acid reflux test, Bernstein test (acid perfusion), esophageal motility study.

Common use

To evaluate potential ineffectiveness of the esophageal muscle and structure in swallowing, vomiting, and regurgitation in diseases such as scleroderma, infection, and gastric esophageal reflux.

Area of application





Esophageal manometry (EM) consists of a group of invasive studies performed to assist in diagnosing abnormalities of esophageal muscle function and esophageal structure. These studies measure esophageal pressure, the effects of gastric acid in the esophagus, lower esophageal sphincter pressure, and motility patterns that result during swallowing. EM can be used to document and quantify gastroesophageal reflux disease (GERD). It is indicated when a patient is experiencing difficulty swallowing, heartburn, regurgitation, or vomiting or has chest pain for which no diagnosis has been found. Tests performed in combination with EM include the acid reflux, acid clearing, and acid perfusion (Bernstein) tests.

This procedure is contraindicated for

  • high alert Patients with unstable cardiopulmonary status, blood coagulation defects, recent gastrointestinal surgery, esophageal varices, or bleeding.


  • Aid in the diagnosis of achalasia, evidenced by increased pressure in EM
  • Aid in the diagnosis of achalasia in children, evidenced by decreased pressure in EM
  • Aid in the diagnosis of esophageal scleroderma, evidenced by decreased pressure in EM
  • Aid in the diagnosis of esophagitis, evidenced by decreased motility
  • Aid in the diagnosis of GERD, evidenced by low pressure in EM, decreased pH in acidity test, and pain in acid reflux and perfusion tests
  • Differentiate between esophagitis or cardiac condition as the cause of epigastric pain
  • Evaluate pyrosis and dysphagia to determine if the cause is GERD or esophagitis

Potential diagnosis

Normal findings

  • Acid clearing: fewer than 10 swallows
  • Acid perfusion: no GERD
  • Acid reflux: no regurgitation into the esophagus
  • Bernstein test: negative
  • Esophageal secretions: pH 5 to 6
  • Esophageal sphincter pressure: 10 to 20 mm Hg

Abnormal findings related to

  • Achalasia (sphincter pressure of 50 mm Hg)
  • Chalasia
  • Esophageal scleroderma
  • Esophagitis
  • GERD (sphincter pressure of 0 to 5 mm Hg, pH of 1 to 3)
  • Hiatal hernia
  • Progressive systemic sclerosis (scleroderma)
  • Spasms

Critical findings


Interfering factors

  • Factors that may impair the results of the examination

    • Inability of the patient to cooperate or remain still during the procedure because of age, significant pain, or mental status.
    • Administration of medications (e.g., sedatives, antacids, anticholinergics, cholinergics, corticosteroids) that can change pH or relax the sphincter muscle, causing inaccurate results.
  • Other considerations

    • Failure to follow dietary restrictions before the procedure may cause the procedure to be canceled or repeated.

Nursing Implications and Procedure


  • Positively identify the patient using at least two unique identifiers before providing care, treatment, or services.
  • Patient Teaching: Inform the patient this procedure can assist in assessing the esophagus.
  • Obtain a history of the patient’s complaints, including a list of known allergens, especially allergies or sensitivities to latex, anesthetics, or sedatives.
  • Obtain a history of the patient’s gastrointestinal system, symptoms, and results of previously performed laboratory tests and diagnostic and surgical procedures.
  • Note any recent barium or other radiological contrast procedures. Ensure that barium studies were performed more than 4 days before the EM.
  • Record the date of the last menstrual period and determine the possibility of pregnancy in perimenopausal women.
  • Obtain a list of the patient’s current medications, including anticoagulants, aspirin and other salicylates, herbs, nutritional supplements, and nutraceuticals (see Effects of Natural Products on Laboratory Values online at DavisPlus). Note the last time and dose of medication taken.
  • Review the procedure with the patient. Address concerns about pain related to the procedure and explain that some pain may be experienced during the test; there may be moments of discomfort and gagging when the scope is inserted, but there are no complications resulting from the procedure; and the throat will be anesthetized with a spray or swab. Inform the patient that he or she will not be able to speak during the procedure but breathing will not be affected. Inform the patient that the procedure is performed in an endoscopy suite by a health-care provider (HCP), under local anesthesia, and takes approximately 30 to 45 min.
  • Sensitivity to social and cultural issues, as well as concern for modesty, is important in providing psychological support before, during, and after the procedure.
  • Explain that an IV line may be inserted to allow infusion of IV fluids such as normal saline, anesthetics, sedatives, or emergency medications.
  • Instruct the patient to remove dentures and eyewear.
  • Under medical direction, the patient should withhold medications for 24 hr before the study; special arrangements may be necessary for diabetic patients.
  • Instruct the patient to fast and restrict fluids for 6 to 8 hr prior to the procedure. Protocols may vary among facilities.
  • Obtain and record baseline vital signs.
  • Make sure a written and informed consent has been signed prior to the procedure and before administering any medications.


  • Potential complications:
  • Establishing an IV site and injection of contrast medium by catheter are invasive procedures. Complications are rare but do include risk for bleeding from the puncture site related to a bleeding disorder, or the effects of natural products and medications known to act as blood thinners, hematoma related to blood leakage into the tissue following needle insertion, or infection that might occur if bacteria from the skin surface is introduced at the puncture site.

  • Observe standard precautions, and follow the general guidelines in Patient Preparation and Specimen Collection. Positively identify the patient.
  • Ensure that the patient has complied with dietary, fluids, and medication restrictions and pretesting preparations for at least 6 to 8 hr prior to the procedure.
  • Ensure the patient has removed dentures and eyewear prior to the procedure.
  • Avoid using morphine sulfate in patients with asthma or other pulmonary disease. This drug can further exacerbate bronchospasms and respiratory impairment.
  • Avoid the use of equipment containing latex if the patient has a history of allergic reaction to latex.
  • Have emergency equipment readily available.
  • Instruct the patient to void prior to the procedure and to change into the gown, robe, and foot coverings provided.
  • Instruct the patient to cooperate fully and to follow directions. Instruct the patient to remain still throughout the procedure because movement produces unreliable results.
  • Establish an IV fluid line for the injection of saline, anesthetics, sedatives, or emergency medications.
  • Spray or swab the oropharynx with a topical local anesthetic.
  • Provide an emesis basin for the increased saliva and encourage the patient to spit out saliva since the gag reflex may be impaired.
  • Monitor the patient for complications related to the procedure (e.g., aspiration of stomach contents into the lungs, dyspnea, tachypnea, adventitious sounds).
  • Suction the mouth, pharynx, and trachea, and administer oxygen as ordered.
  • Esophageal Manometry
  • One or more small tubes are inserted through the nose into the esophagus and stomach.
  • A small transducer is attached to the ends of the tubes to measure lower esophageal sphincter pressure, intraluminal pressures, and regularity and duration of peristaltic contractions.
  • Instruct the patient to swallow small amounts of water or flavored gelatin.
  • Esophageal Acid and Clearing (Tuttle Test)
  • With the tube in place, a pH electrode probe is inserted into the esophagus with Valsalva maneuvers performed to stimulate reflux of stomach contents into the esophagus.
  • If acid reflux is absent, 100 mL of 0.1% hydrochloric acid is instilled into the stomach during a 3-min period, and the pH measurement is repeated.
  • To determine acid clearing, hydrochloric acid is instilled into the esophagus and the patient is asked to swallow while the probe measures the pH.
  • Acid Perfusion (Bernstein Test)
  • A catheter is inserted through the nose into the esophagus, and the patient is asked to inform the HCP when pain is experienced.
  • Normal saline solution is allowed to drip into the catheter at about 10 mL/min. Then hydrochloric acid is allowed to drip into the catheter.
  • Pain experienced when the hydrochloric acid is instilled determines the presence of an esophageal abnormality. If no pain is experienced, symptoms are the result of some other condition.


  • Inform the patient that a report of the results will be made available to the requesting HCP, who will discuss the results with the patient.
  • Monitor the patient for signs of respiratory depression (less than 15 respirations/min) every 15 min for 2 hr. Resuscitation equipment should be available.
  • Observe the patient for indications of perforation: painful swallowing with neck movement, substernal pain with respiration, shoulder pain, dyspnea, abdominal or back pain, cyanosis, and fever.
  • Instruct the patient not to eat or drink until the gag reflex returns and then to eat lightly for 12 to 24 hr.
  • Instruct the patient to resume usual activity, medication, and diet 24 hr after the examination or as tolerated, as directed by the HCP.
  • Inform the patient to expect some throat soreness and possible hoarseness. Advise the patient to use warm gargles, lozenges, or ice packs to the neck and to drink cool fluids to alleviate throat discomfort.
  • Emphasize that any severe pain, fever, difficulty breathing, or expectoration of blood must be reported to the HCP immediately.
  • Recognize anxiety related to test results, and offer support. Discuss the implications of abnormal test results on the patient’s lifestyle. Provide teaching and information regarding the clinical implications of the test results, as appropriate.
  • Reinforce information given by the patient’s HCP regarding further testing, treatment, or referral to another HCP. Answer any questions or address any concerns voiced by the patient or family.
  • Depending on the results of this procedure, additional testing may be needed to evaluate or monitor progression of the disease process and determine the need for a change in therapy. Evaluate test results in relation to the patient’s symptoms and other tests performed.

Related Monographs

  • Related tests include ANA, barium swallow, biopsy skin, capsule endoscopy, chest x-ray, CT thoracic, esophagogastroduodenoscopy, fecal analysis, gastric emptying scan, GERD scan, lung perfusion scan, mediastinoscopy, and upper GI series.
  • Refer to the Gastrointestinal System table at the end of the book for related tests by body system.
Handbook of Laboratory and Diagnostic Tests, © 2013 Farlex and Partners

ac·id re·flux test

(asid rēflŭks test)
Assessment of gastroesophageal reflux by monitoring esophageal pH either basally or after acid is instilled into the stomach.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
However, this test has a sensitivity of only 30%.[32] The addition of special maneuvers such as water-sipping in the head-down position increases the sensitivity but unacceptably lowers the specificity.[33] The standard acid reflux test employs an esophageal pH electrode to measure reflux, which may occur spontaneously or after infusion of hydrochloric acid into the stomach.