- Malposition of the esophageal pH probe sensor too high in esophagus
- Malposition of the esophageal pH probe sensor too low in stomach
- Perforation of the esophagus during placement of esophageal pH probe
Approach to the differential diagnosis of esophageal pH probe malfunction:
- The correct position of the esophageal pH probe sensor (measurement lead) is 3-5 cm above the gastroesophageal junction, otherwise sensor is malpositioned
- Note: Make sure you know which of the radiopaque markings on the catheter is the actual pH probe sensor
- Placement of the esophageal pH probe tip into the airway or lung or pleural space can result in pneumothorax
- Pnemopericardium, pneumomediastium, or pneumothorax after esophageal pH probe placement should raise suspicion for perforation of esophagus
- An esophageal pH probe that is too straight after placement and that does not gently curve into stomach should be suspected of not being in stomach
- An esophageal pH probe tip that projects over the pelvis should be suspected of not being in stomach
- Pneumoperitoneum after esophageal pH probe placement is due to perforation of stomach