How Is an Esophageal Manometry Performed?

Esophageal manometry uses pressure sensors to test the function of the muscles in the esophagus.

The esophagus is the muscular tube that connects the throat and the stomach. The esophagus moves the food down to the stomach with wave-like contractions initiated by swallowing. This process is known as peristalsis.

A valve-like ring of muscles at the top of the esophagus (upper esophageal sphincter) ensures that the food doesn’t enter the windpipe (trachea).

Another ring of muscles at the bottom of the esophagus (lower esophageal sphincter) opens to let the food pass into the stomach and closes to prevent it from coming back up along with stomach acid.

Esophageal manometry is a procedure performed with a thin, flexible, pressure-sensitive tube. The procedure tests the function of the esophagus and the esophageal sphincters by measuring the pressure they generate.

Esophageal manometry is used to determine if the esophageal muscles are functioning normally. Esophageal manometry is usually performed to find the cause of symptoms such as:

• Difficulty swallowing (dysphagia)
• Painful swallowing (odynophagia)
• Feeling of food being stuck in the throat
• Nausea
• Heartburn or reflux
• Non-cardiac chest pain

Esophageal manometry is generally performed after tests such as X-rays and endoscopy fail to demonstrate if the esophagus has any

• obstruction
• narrowing
• inflammation

Esophageal manometry helps in the diagnosis of conditions such as

• Achalasia -- dysfunction of lower esophageal sphincter (LES)
• Distal esophageal spasm -- uncoordinated contractions
• Jackhammer (hypercontractile) esophagus -- extra powerful contractions
• Absent or ineffective peristalsis
• Hypotensive lower esophageal sphincter
• Systemic diseases such as scleroderma, which can paralyze the esophagus

Esophageal manometry may also be performed

• Prior to surgery for gastroesophageal reflux disease (GERD)
• Evaluation post-surgery for GERD or achalasia 
• Esophageal manometry is not advised in patients who
• are unresponsive or unconscious
• are unable to follow instructions
• have known or suspected upper esophageal obstruction or tumors

A gastroenterologist usually performs an esophageal manometry as an outpatient procedure that takes about 15 to 30 minutes.

Preparation

Before the procedure the patient 

• Must not eat or drink anything for 8 hours
• Must check with the doctor before taking any regular medications
• Inform the doctor if they
  • have any allergies
  • have a lung or heart condition
  • are pregnant

Procedure

• The patient initially sits upright.
• The doctor applies a numbing lubricant to the nostril.
• The doctor inserts a thin pressure-sensitive tube gently through the nostril, pharynx, down the esophagus through the LES into the stomach.
• The patient must follow instructions from the doctor and swallow tiny sips of water at intervals.
• After the tube insertion the patient will lie down.
• The manometry machine will record the pressure readings from various points on the tube for the doctor to interpret.
• The doctor will slowly withdraw the tube.
• The patient will be able to leave immediately after the procedure.
• The patient can resume a regular diet after the procedure.

Esophageal manometry is a useful test but has certain limitations. Because swallowing problems and spasms do not occur all the time, there is no certainty that the problems will occur during the test, hence the results may not be conclusive for a diagnosis.

Esophageal manometry is generally not painful. During the insertion of the tube some may feel

• discomfort in the nose and throat
• gagging sensation
• watery eyes

Rarely, some patients may cough or vomit during the insertion of the tube.

Esophageal manometry is generally a safe procedure and complications are rare. There are a few mild side effects such as

• Sore throat
• Stuffy nose
• Minor nosebleed

These side effects usually resolve in a short while, and throat lozenges and salt water gargle help.

There may be a few rare complications such as

• Irregular heartbeat (arrhythmia)
• Drop in heart rate and blood pressure (vasovagal episode)
• Bronchial spasm
• Inhaling gastric contents into the airway (aspiration)
• Perforation of the esophagus
• Insertion of tube into the voice box (larynx)