Twenty-four-hour monitoring of esophagopharyngeal pH in outpatients. Use of four-channel pH probe and computerized system

A 24 hour computerized four-channel esophagopharyngeal pH system is described. Using a 1.5 mm diameter esophageal probe containing four separate antimony-tipped electrodes and a small patient-worn digital recording computer, inpatient and outpatient studies are performed in the physiologic environment of the patient's workplace or home. Stored pH data in the computer are teletransmitted from satellite esophageal pH laboratories to a central esophageal pH laboratory for analysis, scoring, printout, and storage. Satellite laboratories located in hospitals, clinics, and physicians' offices use a minimum of equipment and obtain a quality computer-based printout. This preserves patient-physician relationships in the home environment and is cost-effective. Four case reports are presented identifying the advantages derived from the four-channel system localizing and quantifying the extent of cephalad transport of refluxed upper gastrointestinal content. The system has unique clinical and research potential in all age groups in such disparate problems as sleep apnea, laryngitis, bradycardia and cardiac irregularities, and aspiration pneumonia and pulmonary abscess.