Globus sensation and increased upper esophageal sphincter pressure with distal esophageal acid perfusion

The aim of the present study was to determine whether acid perfusion into the distal esophagus causes a globus sensation and an increase in upper esophageal sphincter (UES) pressure. UES pressures were measured using a sleeve-type sensor in 20 healthy volunteers. A 0.1-N HCl solution, the same as gastric acid, was perfused into the distal esophagus at a rate of 20 mL/min. During perfusion, 4-channel pH monitoring was performed to determine whether the HCl reached the hypopharynx. The following parameters were measured: (1) changes in UES pressure before and during acid perfusion, (2) presence or absence of a globus sensation or heartburn, (3) the time at which a globus sensation or heartburn was noted by the patient and (4) the position of the electrode at which the pH drop was recorded. Ten subjects enrolled as the control group received perfusions of distilled water. Acid perfusion raised the UES pressure in 13 of the 20 subjects. All 13 complained of globus at about the same time as the UES pressure increased. Twelve of the 13 subjects who experienced globus also complained of heartburn, which preceded the globus sensation in ten such cases. None of the control subjects reported globus or had elevated UES pressure. In the acid perfusion group, no pH reduction at the two most cranial electrodes was observed in any subject. In conclusion, the globus sensation is due to elevated UES pressure, resulting from gastroesophageal reflux and does not require direct exposure of the hypopharynx to gastric acid. The incidence of heartburn in combination with a globus sensation would be much higher if the cause of the latter were acid reflux.