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Twenty-four-hour monitoring of esophagopharyngeal pH in outpatients
J
THoRAc CARDIOVASC SURG
91:716-722, 1986
Twenty-four-hour monitoring of esophagopharyngeal pH in outpatients Use offour-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.
William H. Falor, M.D., M.Sc., Joseph Miller, M.D., Jane Kraus, M.D., Stephen Fannin, M.S., Vincent Greczanik, B.S., Norman Crocker, M.D., and Bruce Taylor, Ph.D., Akron. Ohio
Long-term esophageal pH testing is the single most sensitive and accurate method of quantifying gastroesophageal competence and reflux. 1, 2 We have in use a four-channel antimony esophagopharyngeal pH probe' and computerized system" that provides long-term pH sampling every 15 seconds from each of four areas, three equidistant in the esophagus and one in the pharynx. The computer-scored and printed result of each channel documents and quantifies the extent of cephalad flow of acid or alkaline reflux. The system has particular application in hospitalized infants and children.' Outpatient studies in adults are commonly performed in the physiologic environment of home or workplace.v ' Satel-
From the Esophageal Laboratory, Akron City Hospital, Akron, Ohio. Supported by The Akron City Hospital Foundation; The SislerMcFawn Foundation; The Howland Memorial Fund; The W. B. McIntosh Family Fund; Cancer Care Society, United Way, Findlay, Ohio; and The Ashland County Cancer Society. Received for publication March 14, 1985. Accepted for publication June 3, 1985. Address for reprints: Wm. H. Falor, M.D., Akron City Hospital, Akron, Ohio 44309.
716
lite esophageal pH laboratories located in clinics, physician's offices, or in hospitals use a minimum of equipment to complete a pH study and telecommunicate the data to the central esophageal pH laboratory at Akron City Hospital for a four-channel analysis that includes scoring and printout. The system is highly cost-effective, concentrating technical personnel and expensive equipment in the central laboratory for inexpensive widespread satellite use. This report describes our experience with the fourchannel system. Methods and materials Four-channel antimony probes are used. They are small (1.5 mm diameter), soft, pliable, inexpensive, durable, and have lower impedance than glass electrodes. The channels are spaced 3 to 8 em apart to conform to pediatric" and adult? esophageal lengths. The patient-worn, small, 500 gm esophageal pH ambulatory recorder-EpHAR-stores pH data sampled every 15 seconds from each of the four channels for 32 hours of reliable battery life. The recorder is carried in a pouch or placed at the bedside at night and stores pH samples with a resolution of 0.05 pH units. To indicate pH
Volume 91 Number 5
Esophagolaryngeal pH
7 17
May, 1986
storage and proper operation of the unit, a small light-emitting diode (LED) blinks at 15 second intervals. A switch allows the patient to indicate his positionupright or supine. Before and after each use the system is calibrated at three pH values with solutionsof known pH. On completion of the test at a satellite laboratory, the recorder is attached to a modem for telephone transmission to the data-processing computer, an HP-87 XM, at the central esophageal pH laboratory. Thirtytwo hours of data are transmitted in 15 minutes. Objective and subjective events, both standard and nonstandard for esophageal reflux, are rapidly entered in the final printout through use of a coded list. Analysis and scoring are according to the six weighted factors of Johnson and Delvleester": (1) the number of reflux events; (2) the total time the esophageal pH is below 4; (3) the number of episodes of reflux lasting 5 minutes or longer; (4) the duration of the longest episode; and (5) upright or (6) supine percent the pH is below 4 with the scoring weighted in favor of supine reflux. A score of 18 is the upper limit of normal. Johnson's and DeMeester's scoring system was based on continuous pH recording on a strip chart running at 10 ern/hr. At this speed each division of the chart is at 1 minute intervals. One can reliably read such a chart only to 30 second intervals. Our system performs an instantaneous sampling of each channel every 15 seconds. The nyquist criteria require sampling every 15 seconds for any event that might occur every 30 seconds. Thus, by sampling pH every 15 seconds, we, with confidence, capture a transient pH change lasting 30 seconds. A paired comparison of hand-scored versus our computerscored long-termpH studies demonstrated no statistically significant difference.' Statistics including means, standard deviations, and frequency histograms are generated for total, upright, and supine records. The summary report includes the score and trend graphs with a diary of recorded events and histograms drawn on either linear or logarithmic scales. In summary, a long-term esophageal pH study initiated from a satellite pH laboratory starts with nasopharyngeal introduction of the four-channel probe. The lower channel (channel 1) is positioned by x-ray guidance or by pH meter 3 to 5 em above the lower esophageal sphincter (Fig. 1). The upper channel (channel 4) is in the pharynx, and the other two channels are in the middle (channel 2) and upper (channel 3) esophagus. The probe is connected to the EpHAR for the long-term sampling of each pH channel. Intake is limited to nonacidic fluids and foods, with abstinence from tobacco, alcohol, and antacid medications. The
Fig. 1. Four-channel esophagopharyngeal probe. Artist's concept of each pH channel demonstrating acid reflux into upper esophagus.
total pH data in the EpHAR is transmitted by telephone modem to the central esophageal pH laboratory for four-channel analysis and printout. Case reports CASE 1. A hospitalized, severely debilitated, lethargic, diabetic 43-year-old white manhadstaphylococcal pneumonia and lung abscess apparently caused by regurgitation and aspiration. Hiscondition was deteriorating rapidly. An esophagogram taken with the patient semirecumbent showed a questionably competent lower esophageal sphincter, a hypomotile esophagus, and a tightly constricted esophageal lumen at the cricopharyngeal area. Spasm or hypertrophy of this latter muscle was diagnosed," and a cricopharyngotomy was proposed to open the esophagus and prevent further aspiration of refluxed food and fluids from the upper esophagus. Because of the precarious condition of the patient and the doubtful competency of the lower esophageal sphincter, a four-channel 24houresophagopharyngeal pH testwas ordered. Because the hospital did not have a satellite esophageal pH laboratory, a portable esophageal pH unitcontaining a four-channel probe, an EpHAR, a modem, andthreesmall containers ofvaried pH testsolution was used. The pH scores of each channel were as folows: channell (lower esophagus), 56.37; channel 2, 43.59; channel 3, 25.50, channel 4 (pharynx), 31.91. Thus, acid refluxed into the pharynx (Fig. 2).
The Journal of Thoracic and Cardiovascular Surgery
Falor et al.
7 18
CASE #1
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Fig. 2. Case I. Time 2 to 4 AM; pH at left of each channel. Multiple episodes of nocturnal reflux varied in duration, pH, and cephalad transport. Reflux was limited to channel I at 2:06,2:36, and 3:27, but at 3:04 and 3:15 reflux reached the pharynx.
The diagnosis was changed to incompetence of the lower esophageal sphincter with acid-reflux-induced episodic cricopharyngeal spasm, aspiration pneumonia, and abscess. Cricopharyngotomy was canceled. Medical therapy directed toward minimizing acid gastric reflux was followed by ultimate recovery by the patient. Only then was a history of significant heartburn obtainable.
Comment. This debilitated patient was spared an ill-advised, potentially lethal cricopharyngotomy by means of a 24 hour four-channel pH study performed with a portable esophageal pH unit. The portable unit provided a quality esophagopharyngeal pH study at minimal expense. This technique is cost-effective, it eliminates capital outlay, and it is of special value in institutions, clinics, and offices where a limited number of pH studies are performed. CASE 2. A l-rnonth-old, 1,400 gm white boy was admitted to the Children's Hospital with episodes of apnea and bradycardia and failure to thrive. The child, delivered prematurely at 29 weeks at a weight of 1,210 gm, had a resistant
enterocolitis with gangrene of the terminal ileum and cecum for which an ileocolic resection and terminal ileostomy were performed at 9 days of age. Frequent episodesof vomitingthen developed, often associated with apnea and bradycardia. The latter responded to minimal stimuli, and a tentative diagnosis was made of lower esophageal incompetence with reflux and possible secondary apnea and bradycardia. A 24 hour esophagopharyngeal pH test was performed with the pediatric four-channel probe, with electrodes spaced at 4 em intervals. Because the infant was 50 em long, the lowertwo channels were in the esophagus, the third was in the pharynx, and the upper electrode was in the nares. The three functioning channels showed significant reflux: Channel I scored 138.20, channel 2 scored 131.23; and channel 3 scored 95.80. Thus, gastric acid refluxed throughout the esophagopharyngeal area. Semi-upright position and round-the-clock tube feedings led to lessening of regurgitation and to weight gain. During the succeeding 2 week hospitalization the episodes of apnea and bradycardia ceased. An antireflux procedure was canceled for further observation.
Comment. The 24 hour esophageal pH study was started at 2 P.M. and was followed by frequent episodes of apnea and bradycardia that responded to "gentle stimulation." With adaptation to the esophageal probe, the attacks slackened." During many episodes of apnea and bradycardia (Fig. 3, 6 to 8 PM) the pH did not change or dropped only in the lower esophageal area (channell). At 8 P.M. the pH dropped and remained below 4 until midnight; frequent attacks of apnea, 13
Volume 91
Esophagolaryngeal pH
Number 5 May, 1986
bradycardia, sneezing, and coughing followed the onset of this episode of reflux (Fig. 4). Thus, in this infant, apnea and bradycardia occurred in both the presence and absence of reflux. The probe was too long; however, because of the multiple electrodes, the functioning three electrodes finally were positioned between the lower esophagus and pharynx. In children the formula of Strobel and associates' for measuring esophageal length, or the use of x-ray guidance, allows probes of proper length to be selected. In adults the external chest measurement of Kalloor, Deshpande, and Collis? is a valuable guide to esophageal length. An antireflux procedure was deferred because of the rapid, complete response to medical therapy and to allow maximum esophageal maturation." 3. A 3-year-old retarded white girl was admitted to Children's Hospital with a history of recurrent cough, vomiting with occasional hematemesis, and failure to thrive. On esophagoscopy there was minimal erythema of the lower esophagus. Tentative diagnosis related the cough, vomiting, and hematemesis to esophagopharyngeal reflux. A 24 hour esophageal pH study yielded the following scores: Channell, 60.78; channel 2, 7.97; channel 3, 0.18; and channel 4 (pharynx), 0.15. Thus, reflux, significant in degree, was limited to the lower esophagus. The child, institutionalized from birth, required almost constant care because of the vomiting. A further concern was the hematemesis. A Nissen fundoplication was performed to eliminate these problems. In the following 5 months, the infant gained weight and the recurrent hematemesis, cough, and vomiting abated. A repeat 24 hour esophageal pH study yielded the following scores: channel I, 32.04 (Fig. 5); channel 2, 10.60; channel 3, 0.09; and channel 4, 0.00. CASE
Comment. The antireflux procedure reduced but did not eliminate the reflux; thus, the child remains at risk despite the remarkable recovery on medical care. The presenting problems were indicative of reflux into the pharynx and aspiration. A single-channel lower esophageal pH study would have shown lower esophageal reflux, and it could have been assumed that the cough related to aspiration of refluxed material reaching the pharynx.IS However, the four-channel study showed reflux limited to the lower esophagus. Thus, the pulmonary symptoms and at least part of the vomiting in all probability relate to causes other than reflux. The consistent reflux-free scores of channels 2, 3, and 4 in the pH studies performed at 5 month intervals demonstrate the reproducibility of the four-channel studyand the proper location of the channel I electrode, 3 to 5 em above the lower esophageal sphincter, where the score of 32.04 indicated moderate reflux. If the
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Fig. 4. Case 2. Time 10 PM to midnight (22:00 to 24:00). Nocturnal esophagopharyngeal reflux, pH 1 to 2, for 1 hour with multiple episodes of apnea and bradycardia that responded to "moderate stimulation."
channel I electrode had been in the middle esophagus, where the score was a normal 10.60, the reflux would not have been detected. CASE 4. A 13-year-old mentally retarded white girl with multiple congenital anomalies was admitted to Children's Hospital with a 1 month history of vomiting with every meal and a history of frequent bouts of pneumonia since birth. There was no prior history of significant vomiting. An upper gastrointestinal x-ray series demonstrated normal gastric emptying and a competent lower esophageal sphincter without any reflux. Scores of a teletransmitted 24 hour esophageal pH test were as follows: channel 1,48.21; channel 2, 28.67; channel 3, 30.55; and channel 4, 30.70. Thus, acid reflux of moderate degree bathed the esophagus and lower pharynx. An antireflux operation was considered, but because of the severe mental retardation, medical therapy was instituted. Vomiting tapered off, liquids were retained, weight increased, and the patient was discharged.
Comment. This was the first episode of apparent reflux-induced significant vomiting in this severely disadvantaged adolescent. Thus, management was nonoperative. With recurrences, an antireflux procedure may be performed to reduce or eliminate vomiting episodes and to reduce hospitalization and the need for intensive nursing care.
7 20
The Journal of Thoracic and Cardiovascular Surgery
Falor et aJ.
ESOPHAGEAL LABORATORY - AKRON CITY HOSPITAL 24HR ESOPHAGEAL pH TEST REPORT CHANNEL 1 Date : 1/31/84 Symptoms:
Comments: *4 yean *R.urded · Post -Nisle a - 8131/84
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SUPINE TIME :
Total Time (Min.) Time pH <4 (min .) "TimepH<4 .. Reflux Eventl ., E'nDb> 5 Min Lonqm Event (Min.) Clearance Tim. (Min .) MoonpH +/- S.D. Total Time (Min.) Time pH< 4 (Min.) " Time pH <4 (Min.) .. Renux EYenti .. Evenu> 5 Min . Lo"'lest Event (Min.) Ouranc. Tim. (Min.) M.n pH +/- S.D. Total Time (Min.) Time pH< 4 (Min.) " Time pH <4 (Min .) #I Rlflux Eventl • Eventl> 5 Min . Lo"'lest Event (Min.) CI.rance Time (Min.) Moon pH +/- S.D.
1539.25 99 .75 6.48
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Comparilon with the record of 8128/84 reveals that the first-ehannel renux with only 1/2 thlt ot the former reecrd.
Fig. 5. Case 3. First page of postoperative report including the resume of channell and the final "Diagnosis and comments."
X-ray studies failed to demonstrate an incompetent lower esophageal sphincter and reflux even into the lower esophagus; the 24 hour esophageal pH test demonstrated reflux through the entire esophagus into the pharynx. The pH test has been an accurate physiologic index of acid reflux and has been the basis for development of the most precise quantitative evaluation of all commonly used tests." The pH test quantitates two important determinants of reflux esophagitis: (I) reflux secondary to an incompetent cardioesophageal junction and (2) the rate of esophageal clearance of refluxed material-acid or alkaline. In this type of
severely symptomatic patient the pH test has a 92% accuracy rate with no false-positive findings." Discussion Continuous intraluminal pH monitoring of the lower esophagus for 24 hours is accepted as the most accurate diagnostic procedure in evaluating esophageal reflux at any age. 1,2 Our computer-based four-channel esophageal pH system documents and quantifies the extent of cephalad transport of refluxed material into the esophagus and pharynx. It, as well as the single-channel system, will
Volume 91 Number 5
Esophagolaryngeal pH
721
May, 1986
relate reflux to problems of the lower esophagus (such as esophagitis, ulceration, hemorrhage, and stricture) and will document the effectiveness of antireflux operations. The significant advantage to the four-channel system is the objectivity it provides in all age groups to the potential relationship of reflux to a variety of identified as well as occult problems: (1) prolonged vomiting" (Case 4); (2) mid-esophageal and upper-esophageal lesions, for example, esophagitis, ulceration, hemorrhage, and spasm, including cricopharyngeal spasm II (Case 1); (3) recurrent aspiration-induced pulmonary sepsis" (Cases 1 and 4); (4) laryngitis and laryngeal polyps"; (5) bronchial asthma"; (6) sleep apnea and sudden infant death syndrome'<" (Case 2); (7) bradycardia (case 2) and other cardiac rhythm abnormalities"; and (8) failure to thrive'-" (Cases 2 and 3). In our first 100 long-term four-channel esophageal pH studies, we have encountered one or more cases of each of these categories. The system provides a highquality study, but the case load is too small for statistical analysis. It is already apparent that the system is very useful in the pediatric patient, particularly in the mentally disadvantaged child in whom almost everyone of the aforementioned problems is commonplace. The relationship of gastropharyngeal reflux to bronchial asthma and sleep apnea is currently being investigated. The system uses the Holter concept for teletransmission of long-term esophageal pH data from satellite esophageal pH laboratories to a central esophageal pH laboratory, where the data from each of the four channels are rapidly analyzed, scored, printed out for the referring sources, and stored for future comparison and reference. By eliminating expensive technical personnel and equipment in the satellite and by performing outpatient studies in the patient's home or workplace, his physiologic environment, the system preserves patientphysician relationships and is highly cost-effective. The four-channel esophageal pH system, including the portable pH unit, opens to virtually every clinical facility a unique approach to an objective analysis of a number of medical problems related to the pathophysiology of esophagopharyngeal reflux. It also provides a versatile tool for clinical research in a wide field of apparent reflux-induced problems. REFERENCES DeMeester TR, Wang CI, Wernly JA, Pellegrini CA, Little AG, Klementschitsch P, Bermudez G, Johnson LF, Skinner DB: Technique, indications, and clinical use of 24-hour esophageal pH monitoring. J THORAC CARDlOVASC SURG 79:656-670, 1980
2 Fink SM, McCallum RW: The role of prolonged esophageal pH monitoring in the diagnosis of gastroesophageal reflux. JAMA 252:1160-i 164, 1984 3 Jones RD, Neuman MR, Sanders G, Cross FS: Miniature antimony pH electrodes for measuring gastroesophageal reflux. Ann Thorac Surg 33:491-495, 1982 4 Miller JM, Fannin SW, Steiner PR, Kraus JM, Falor WH, Taylor BC: Instrumentation for the automatic recording and analysis of esophageal pH, Esophageal Disorders. Pathophysiology and Therapy,TR DeMeester,DBSkinner, eds.,New York, 1985,Raven Press,pp 133-I4I 5 Falor WH, Miller J, Kraus J, Fannin S, Taylor B, Greczanik V, Steiner P, Crocker N: Out-patient computer-based 32-hour esophageal pH studies teletransmitted to a central esophageal pH laboratory. Arch Intern Med 145:1617-1619, 1985 6 Falor WH, Chang B, White HA, Kraus JM, Taylor B, Hansel JR, Kraus FC: Twenty-four hour esophageal pH monitoring by telemetry. Am J Surg 142:514-516, 1981 7 Branicki FJ, Evans DF, Ogilvie AL, Atkinson M, Hardcastle JD: Ambulatory monitoring of oesophageal pH in refluxoesophagitis using a portable radiotelemetry system. Gut 23:992-998, 1982 8 Strobel CT, Byrne WJ, Ament ME, Euler AR: Correlation of esophageal lengths in children with height. Application to the Tuttle test without prior esophageal manometry. J Pediatric 94:8 I-84, 1979 9 Kalloor GJ, Deshpande AH, Collis JL: Observations on oesophageal length, Thorax 31:284-288, 1976 10 Johnson LF, DeMeester TR: Twenty-four hour pH monitoring of the distal esophagus. Am J Gastroenterol 62:325332, 1974 II Henderson RD, Hanna W, Marryatt G, Kando M: Cricopharyngealdysphagia secondary to gastroesophageal reflux. Clinical, investigative, and pathologic findings, Esophageal Disorders. Pathophysiology and Therapy, TR DeMeester, DB Skinner, eds., New York, 1985, Raven Press, pp 169-I75 12 Kenigsberg K, Griswold PG, Buckley BJ" Gootman N, Gootman PM: Cardiac effects of esophageal stimulation. Possible relationship between gastroesophageal reflux (GER) and sudden infant death syndrome (SIOS). J Pediatr Surg 18:542-545, 1983 13 Leape LL, Holder TM, Franklin JD, Amoury RA, Ashcraft KW: Respiratory arrest in infants secondary to gastroesophageal reflux. J Pediatr 60:924-928, 1977 14 Boix-Ochoa J, Canals J: Maturation of the lower esophagus. J Pediatr Surg 11:749-756, 1976 15 Christie DL, O'Grady LR, Mack DV: Incompetent lower esophageal sphincter and gastroesophagealreflux in recurrent acute pulmonary disease of infancy and childhood. J Pediatr 93:23-27, 1978 16 DeMeester TR, Johnson LF: The evaluation of objective measurements of gastroesophageal reflux and their contribution to patient management. Surg Clin North Am 56:39-53, 1976 17 Bryne WJ, Eular AR, Ashcraft E, Nash DG, Seibert JJ,
722
Falor et al.
Golliday ES: Gastroesophageal reflux in the severely retarded who vomit. Criteria for and results of surgical intervention in 22 patients. Surgery 91:95-98, 1982 18 Delahunty JE: Acid laryngitis. J Laryngol Otol 86:335342, 1972 19 Perpina M, Ponce J, Marco V: The prevalence of asymptomatic gastroesophageal reflux in bronchial asthma and in non-asthmatic individuals. Eur J Respir Dis 64:582587, 1983
The Journal of Thoracic and Cardiovascular Surgery
20 Herbst JJ, Book LS, Bray PF: Gastroesophageal reflux in the "near miss" sudden infant death syndrome. J Pediatr 92:73-75, 1978 21 Schey WL, Meus P, Levinsky RA, Campbell C, Replogle R: Esophageal dysmotility and the sudden infant death syndrome. Pediatr Radiol 140:73-77, 1981 22 Herbst JJ: Gastroesophageal reflux and pulmonary disease. Pediatrics 68: 132-134, 1981
Bound volumes available to subscribers Bound volumes of THE JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY are available to subscribers (only) for the 1986 issues from the Publisher, at a cost of $49.00 ($66.00 international) for Vol. 91 (January-June) and Vol. 92 (July-December). Shipping charges are included. Each bound volume contains a subject and author index and all advertising is removed. Copies are shipped within 60 days after publication of the last issue of the volume. The binding is durable buckram with the JOURNAL name, volume number, and year stamped in gold on the spine. Payment must accompany all orders. Contact The C. V. Mosby Company, Circulation Department, 11830 Westline Industrial Drive, St. Louis, Missouri 63146, USA; phone (800) 325-4177, ext. 351. Subscriptions must be in force to qualify. Bound volumes are not available in place of a regular JOURNAL subscription.
THoRAc CARDIOVASC SURG
91:716-722, 1986
Twenty-four-hour monitoring of esophagopharyngeal pH in outpatients Use offour-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.
William H. Falor, M.D., M.Sc., Joseph Miller, M.D., Jane Kraus, M.D., Stephen Fannin, M.S., Vincent Greczanik, B.S., Norman Crocker, M.D., and Bruce Taylor, Ph.D., Akron. Ohio
Long-term esophageal pH testing is the single most sensitive and accurate method of quantifying gastroesophageal competence and reflux. 1, 2 We have in use a four-channel antimony esophagopharyngeal pH probe' and computerized system" that provides long-term pH sampling every 15 seconds from each of four areas, three equidistant in the esophagus and one in the pharynx. The computer-scored and printed result of each channel documents and quantifies the extent of cephalad flow of acid or alkaline reflux. The system has particular application in hospitalized infants and children.' Outpatient studies in adults are commonly performed in the physiologic environment of home or workplace.v ' Satel-
From the Esophageal Laboratory, Akron City Hospital, Akron, Ohio. Supported by The Akron City Hospital Foundation; The SislerMcFawn Foundation; The Howland Memorial Fund; The W. B. McIntosh Family Fund; Cancer Care Society, United Way, Findlay, Ohio; and The Ashland County Cancer Society. Received for publication March 14, 1985. Accepted for publication June 3, 1985. Address for reprints: Wm. H. Falor, M.D., Akron City Hospital, Akron, Ohio 44309.
716
lite esophageal pH laboratories located in clinics, physician's offices, or in hospitals use a minimum of equipment to complete a pH study and telecommunicate the data to the central esophageal pH laboratory at Akron City Hospital for a four-channel analysis that includes scoring and printout. The system is highly cost-effective, concentrating technical personnel and expensive equipment in the central laboratory for inexpensive widespread satellite use. This report describes our experience with the fourchannel system. Methods and materials Four-channel antimony probes are used. They are small (1.5 mm diameter), soft, pliable, inexpensive, durable, and have lower impedance than glass electrodes. The channels are spaced 3 to 8 em apart to conform to pediatric" and adult? esophageal lengths. The patient-worn, small, 500 gm esophageal pH ambulatory recorder-EpHAR-stores pH data sampled every 15 seconds from each of the four channels for 32 hours of reliable battery life. The recorder is carried in a pouch or placed at the bedside at night and stores pH samples with a resolution of 0.05 pH units. To indicate pH
Volume 91 Number 5
Esophagolaryngeal pH
7 17
May, 1986
storage and proper operation of the unit, a small light-emitting diode (LED) blinks at 15 second intervals. A switch allows the patient to indicate his positionupright or supine. Before and after each use the system is calibrated at three pH values with solutionsof known pH. On completion of the test at a satellite laboratory, the recorder is attached to a modem for telephone transmission to the data-processing computer, an HP-87 XM, at the central esophageal pH laboratory. Thirtytwo hours of data are transmitted in 15 minutes. Objective and subjective events, both standard and nonstandard for esophageal reflux, are rapidly entered in the final printout through use of a coded list. Analysis and scoring are according to the six weighted factors of Johnson and Delvleester": (1) the number of reflux events; (2) the total time the esophageal pH is below 4; (3) the number of episodes of reflux lasting 5 minutes or longer; (4) the duration of the longest episode; and (5) upright or (6) supine percent the pH is below 4 with the scoring weighted in favor of supine reflux. A score of 18 is the upper limit of normal. Johnson's and DeMeester's scoring system was based on continuous pH recording on a strip chart running at 10 ern/hr. At this speed each division of the chart is at 1 minute intervals. One can reliably read such a chart only to 30 second intervals. Our system performs an instantaneous sampling of each channel every 15 seconds. The nyquist criteria require sampling every 15 seconds for any event that might occur every 30 seconds. Thus, by sampling pH every 15 seconds, we, with confidence, capture a transient pH change lasting 30 seconds. A paired comparison of hand-scored versus our computerscored long-termpH studies demonstrated no statistically significant difference.' Statistics including means, standard deviations, and frequency histograms are generated for total, upright, and supine records. The summary report includes the score and trend graphs with a diary of recorded events and histograms drawn on either linear or logarithmic scales. In summary, a long-term esophageal pH study initiated from a satellite pH laboratory starts with nasopharyngeal introduction of the four-channel probe. The lower channel (channel 1) is positioned by x-ray guidance or by pH meter 3 to 5 em above the lower esophageal sphincter (Fig. 1). The upper channel (channel 4) is in the pharynx, and the other two channels are in the middle (channel 2) and upper (channel 3) esophagus. The probe is connected to the EpHAR for the long-term sampling of each pH channel. Intake is limited to nonacidic fluids and foods, with abstinence from tobacco, alcohol, and antacid medications. The
Fig. 1. Four-channel esophagopharyngeal probe. Artist's concept of each pH channel demonstrating acid reflux into upper esophagus.
total pH data in the EpHAR is transmitted by telephone modem to the central esophageal pH laboratory for four-channel analysis and printout. Case reports CASE 1. A hospitalized, severely debilitated, lethargic, diabetic 43-year-old white manhadstaphylococcal pneumonia and lung abscess apparently caused by regurgitation and aspiration. Hiscondition was deteriorating rapidly. An esophagogram taken with the patient semirecumbent showed a questionably competent lower esophageal sphincter, a hypomotile esophagus, and a tightly constricted esophageal lumen at the cricopharyngeal area. Spasm or hypertrophy of this latter muscle was diagnosed," and a cricopharyngotomy was proposed to open the esophagus and prevent further aspiration of refluxed food and fluids from the upper esophagus. Because of the precarious condition of the patient and the doubtful competency of the lower esophageal sphincter, a four-channel 24houresophagopharyngeal pH testwas ordered. Because the hospital did not have a satellite esophageal pH laboratory, a portable esophageal pH unitcontaining a four-channel probe, an EpHAR, a modem, andthreesmall containers ofvaried pH testsolution was used. The pH scores of each channel were as folows: channell (lower esophagus), 56.37; channel 2, 43.59; channel 3, 25.50, channel 4 (pharynx), 31.91. Thus, acid refluxed into the pharynx (Fig. 2).
The Journal of Thoracic and Cardiovascular Surgery
Falor et al.
7 18
CASE #1
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Fig. 2. Case I. Time 2 to 4 AM; pH at left of each channel. Multiple episodes of nocturnal reflux varied in duration, pH, and cephalad transport. Reflux was limited to channel I at 2:06,2:36, and 3:27, but at 3:04 and 3:15 reflux reached the pharynx.
The diagnosis was changed to incompetence of the lower esophageal sphincter with acid-reflux-induced episodic cricopharyngeal spasm, aspiration pneumonia, and abscess. Cricopharyngotomy was canceled. Medical therapy directed toward minimizing acid gastric reflux was followed by ultimate recovery by the patient. Only then was a history of significant heartburn obtainable.
Comment. This debilitated patient was spared an ill-advised, potentially lethal cricopharyngotomy by means of a 24 hour four-channel pH study performed with a portable esophageal pH unit. The portable unit provided a quality esophagopharyngeal pH study at minimal expense. This technique is cost-effective, it eliminates capital outlay, and it is of special value in institutions, clinics, and offices where a limited number of pH studies are performed. CASE 2. A l-rnonth-old, 1,400 gm white boy was admitted to the Children's Hospital with episodes of apnea and bradycardia and failure to thrive. The child, delivered prematurely at 29 weeks at a weight of 1,210 gm, had a resistant
enterocolitis with gangrene of the terminal ileum and cecum for which an ileocolic resection and terminal ileostomy were performed at 9 days of age. Frequent episodesof vomitingthen developed, often associated with apnea and bradycardia. The latter responded to minimal stimuli, and a tentative diagnosis was made of lower esophageal incompetence with reflux and possible secondary apnea and bradycardia. A 24 hour esophagopharyngeal pH test was performed with the pediatric four-channel probe, with electrodes spaced at 4 em intervals. Because the infant was 50 em long, the lowertwo channels were in the esophagus, the third was in the pharynx, and the upper electrode was in the nares. The three functioning channels showed significant reflux: Channel I scored 138.20, channel 2 scored 131.23; and channel 3 scored 95.80. Thus, gastric acid refluxed throughout the esophagopharyngeal area. Semi-upright position and round-the-clock tube feedings led to lessening of regurgitation and to weight gain. During the succeeding 2 week hospitalization the episodes of apnea and bradycardia ceased. An antireflux procedure was canceled for further observation.
Comment. The 24 hour esophageal pH study was started at 2 P.M. and was followed by frequent episodes of apnea and bradycardia that responded to "gentle stimulation." With adaptation to the esophageal probe, the attacks slackened." During many episodes of apnea and bradycardia (Fig. 3, 6 to 8 PM) the pH did not change or dropped only in the lower esophageal area (channell). At 8 P.M. the pH dropped and remained below 4 until midnight; frequent attacks of apnea, 13
Volume 91
Esophagolaryngeal pH
Number 5 May, 1986
bradycardia, sneezing, and coughing followed the onset of this episode of reflux (Fig. 4). Thus, in this infant, apnea and bradycardia occurred in both the presence and absence of reflux. The probe was too long; however, because of the multiple electrodes, the functioning three electrodes finally were positioned between the lower esophagus and pharynx. In children the formula of Strobel and associates' for measuring esophageal length, or the use of x-ray guidance, allows probes of proper length to be selected. In adults the external chest measurement of Kalloor, Deshpande, and Collis? is a valuable guide to esophageal length. An antireflux procedure was deferred because of the rapid, complete response to medical therapy and to allow maximum esophageal maturation." 3. A 3-year-old retarded white girl was admitted to Children's Hospital with a history of recurrent cough, vomiting with occasional hematemesis, and failure to thrive. On esophagoscopy there was minimal erythema of the lower esophagus. Tentative diagnosis related the cough, vomiting, and hematemesis to esophagopharyngeal reflux. A 24 hour esophageal pH study yielded the following scores: Channell, 60.78; channel 2, 7.97; channel 3, 0.18; and channel 4 (pharynx), 0.15. Thus, reflux, significant in degree, was limited to the lower esophagus. The child, institutionalized from birth, required almost constant care because of the vomiting. A further concern was the hematemesis. A Nissen fundoplication was performed to eliminate these problems. In the following 5 months, the infant gained weight and the recurrent hematemesis, cough, and vomiting abated. A repeat 24 hour esophageal pH study yielded the following scores: channel I, 32.04 (Fig. 5); channel 2, 10.60; channel 3, 0.09; and channel 4, 0.00. CASE
Comment. The antireflux procedure reduced but did not eliminate the reflux; thus, the child remains at risk despite the remarkable recovery on medical care. The presenting problems were indicative of reflux into the pharynx and aspiration. A single-channel lower esophageal pH study would have shown lower esophageal reflux, and it could have been assumed that the cough related to aspiration of refluxed material reaching the pharynx.IS However, the four-channel study showed reflux limited to the lower esophagus. Thus, the pulmonary symptoms and at least part of the vomiting in all probability relate to causes other than reflux. The consistent reflux-free scores of channels 2, 3, and 4 in the pH studies performed at 5 month intervals demonstrate the reproducibility of the four-channel studyand the proper location of the channel I electrode, 3 to 5 em above the lower esophageal sphincter, where the score of 32.04 indicated moderate reflux. If the
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channel I electrode had been in the middle esophagus, where the score was a normal 10.60, the reflux would not have been detected. CASE 4. A 13-year-old mentally retarded white girl with multiple congenital anomalies was admitted to Children's Hospital with a 1 month history of vomiting with every meal and a history of frequent bouts of pneumonia since birth. There was no prior history of significant vomiting. An upper gastrointestinal x-ray series demonstrated normal gastric emptying and a competent lower esophageal sphincter without any reflux. Scores of a teletransmitted 24 hour esophageal pH test were as follows: channel 1,48.21; channel 2, 28.67; channel 3, 30.55; and channel 4, 30.70. Thus, acid reflux of moderate degree bathed the esophagus and lower pharynx. An antireflux operation was considered, but because of the severe mental retardation, medical therapy was instituted. Vomiting tapered off, liquids were retained, weight increased, and the patient was discharged.
Comment. This was the first episode of apparent reflux-induced significant vomiting in this severely disadvantaged adolescent. Thus, management was nonoperative. With recurrences, an antireflux procedure may be performed to reduce or eliminate vomiting episodes and to reduce hospitalization and the need for intensive nursing care.
7 20
The Journal of Thoracic and Cardiovascular Surgery
Falor et aJ.
ESOPHAGEAL LABORATORY - AKRON CITY HOSPITAL 24HR ESOPHAGEAL pH TEST REPORT CHANNEL 1 Date : 1/31/84 Symptoms:
Comments: *4 yean *R.urded · Post -Nisle a - 8131/84
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Total Time (Min.) Time pH <4 (min .) "TimepH<4 .. Reflux Eventl ., E'nDb> 5 Min Lonqm Event (Min.) Clearance Tim. (Min .) MoonpH +/- S.D. Total Time (Min.) Time pH< 4 (Min.) " Time pH <4 (Min.) .. Renux EYenti .. Evenu> 5 Min . Lo"'lest Event (Min.) Ouranc. Tim. (Min.) M.n pH +/- S.D. Total Time (Min.) Time pH< 4 (Min.) " Time pH <4 (Min .) #I Rlflux Eventl • Eventl> 5 Min . Lo"'lest Event (Min.) CI.rance Time (Min.) Moon pH +/- S.D.
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Fig. 5. Case 3. First page of postoperative report including the resume of channell and the final "Diagnosis and comments."
X-ray studies failed to demonstrate an incompetent lower esophageal sphincter and reflux even into the lower esophagus; the 24 hour esophageal pH test demonstrated reflux through the entire esophagus into the pharynx. The pH test has been an accurate physiologic index of acid reflux and has been the basis for development of the most precise quantitative evaluation of all commonly used tests." The pH test quantitates two important determinants of reflux esophagitis: (I) reflux secondary to an incompetent cardioesophageal junction and (2) the rate of esophageal clearance of refluxed material-acid or alkaline. In this type of
severely symptomatic patient the pH test has a 92% accuracy rate with no false-positive findings." Discussion Continuous intraluminal pH monitoring of the lower esophagus for 24 hours is accepted as the most accurate diagnostic procedure in evaluating esophageal reflux at any age. 1,2 Our computer-based four-channel esophageal pH system documents and quantifies the extent of cephalad transport of refluxed material into the esophagus and pharynx. It, as well as the single-channel system, will
Volume 91 Number 5
Esophagolaryngeal pH
721
May, 1986
relate reflux to problems of the lower esophagus (such as esophagitis, ulceration, hemorrhage, and stricture) and will document the effectiveness of antireflux operations. The significant advantage to the four-channel system is the objectivity it provides in all age groups to the potential relationship of reflux to a variety of identified as well as occult problems: (1) prolonged vomiting" (Case 4); (2) mid-esophageal and upper-esophageal lesions, for example, esophagitis, ulceration, hemorrhage, and spasm, including cricopharyngeal spasm II (Case 1); (3) recurrent aspiration-induced pulmonary sepsis" (Cases 1 and 4); (4) laryngitis and laryngeal polyps"; (5) bronchial asthma"; (6) sleep apnea and sudden infant death syndrome'<" (Case 2); (7) bradycardia (case 2) and other cardiac rhythm abnormalities"; and (8) failure to thrive'-" (Cases 2 and 3). In our first 100 long-term four-channel esophageal pH studies, we have encountered one or more cases of each of these categories. The system provides a highquality study, but the case load is too small for statistical analysis. It is already apparent that the system is very useful in the pediatric patient, particularly in the mentally disadvantaged child in whom almost everyone of the aforementioned problems is commonplace. The relationship of gastropharyngeal reflux to bronchial asthma and sleep apnea is currently being investigated. The system uses the Holter concept for teletransmission of long-term esophageal pH data from satellite esophageal pH laboratories to a central esophageal pH laboratory, where the data from each of the four channels are rapidly analyzed, scored, printed out for the referring sources, and stored for future comparison and reference. By eliminating expensive technical personnel and equipment in the satellite and by performing outpatient studies in the patient's home or workplace, his physiologic environment, the system preserves patientphysician relationships and is highly cost-effective. The four-channel esophageal pH system, including the portable pH unit, opens to virtually every clinical facility a unique approach to an objective analysis of a number of medical problems related to the pathophysiology of esophagopharyngeal reflux. It also provides a versatile tool for clinical research in a wide field of apparent reflux-induced problems. REFERENCES DeMeester TR, Wang CI, Wernly JA, Pellegrini CA, Little AG, Klementschitsch P, Bermudez G, Johnson LF, Skinner DB: Technique, indications, and clinical use of 24-hour esophageal pH monitoring. J THORAC CARDlOVASC SURG 79:656-670, 1980
2 Fink SM, McCallum RW: The role of prolonged esophageal pH monitoring in the diagnosis of gastroesophageal reflux. JAMA 252:1160-i 164, 1984 3 Jones RD, Neuman MR, Sanders G, Cross FS: Miniature antimony pH electrodes for measuring gastroesophageal reflux. Ann Thorac Surg 33:491-495, 1982 4 Miller JM, Fannin SW, Steiner PR, Kraus JM, Falor WH, Taylor BC: Instrumentation for the automatic recording and analysis of esophageal pH, Esophageal Disorders. Pathophysiology and Therapy,TR DeMeester,DBSkinner, eds.,New York, 1985,Raven Press,pp 133-I4I 5 Falor WH, Miller J, Kraus J, Fannin S, Taylor B, Greczanik V, Steiner P, Crocker N: Out-patient computer-based 32-hour esophageal pH studies teletransmitted to a central esophageal pH laboratory. Arch Intern Med 145:1617-1619, 1985 6 Falor WH, Chang B, White HA, Kraus JM, Taylor B, Hansel JR, Kraus FC: Twenty-four hour esophageal pH monitoring by telemetry. Am J Surg 142:514-516, 1981 7 Branicki FJ, Evans DF, Ogilvie AL, Atkinson M, Hardcastle JD: Ambulatory monitoring of oesophageal pH in refluxoesophagitis using a portable radiotelemetry system. Gut 23:992-998, 1982 8 Strobel CT, Byrne WJ, Ament ME, Euler AR: Correlation of esophageal lengths in children with height. Application to the Tuttle test without prior esophageal manometry. J Pediatric 94:8 I-84, 1979 9 Kalloor GJ, Deshpande AH, Collis JL: Observations on oesophageal length, Thorax 31:284-288, 1976 10 Johnson LF, DeMeester TR: Twenty-four hour pH monitoring of the distal esophagus. Am J Gastroenterol 62:325332, 1974 II Henderson RD, Hanna W, Marryatt G, Kando M: Cricopharyngealdysphagia secondary to gastroesophageal reflux. Clinical, investigative, and pathologic findings, Esophageal Disorders. Pathophysiology and Therapy, TR DeMeester, DB Skinner, eds., New York, 1985, Raven Press, pp 169-I75 12 Kenigsberg K, Griswold PG, Buckley BJ" Gootman N, Gootman PM: Cardiac effects of esophageal stimulation. Possible relationship between gastroesophageal reflux (GER) and sudden infant death syndrome (SIOS). J Pediatr Surg 18:542-545, 1983 13 Leape LL, Holder TM, Franklin JD, Amoury RA, Ashcraft KW: Respiratory arrest in infants secondary to gastroesophageal reflux. J Pediatr 60:924-928, 1977 14 Boix-Ochoa J, Canals J: Maturation of the lower esophagus. J Pediatr Surg 11:749-756, 1976 15 Christie DL, O'Grady LR, Mack DV: Incompetent lower esophageal sphincter and gastroesophagealreflux in recurrent acute pulmonary disease of infancy and childhood. J Pediatr 93:23-27, 1978 16 DeMeester TR, Johnson LF: The evaluation of objective measurements of gastroesophageal reflux and their contribution to patient management. Surg Clin North Am 56:39-53, 1976 17 Bryne WJ, Eular AR, Ashcraft E, Nash DG, Seibert JJ,
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Golliday ES: Gastroesophageal reflux in the severely retarded who vomit. Criteria for and results of surgical intervention in 22 patients. Surgery 91:95-98, 1982 18 Delahunty JE: Acid laryngitis. J Laryngol Otol 86:335342, 1972 19 Perpina M, Ponce J, Marco V: The prevalence of asymptomatic gastroesophageal reflux in bronchial asthma and in non-asthmatic individuals. Eur J Respir Dis 64:582587, 1983
The Journal of Thoracic and Cardiovascular Surgery
20 Herbst JJ, Book LS, Bray PF: Gastroesophageal reflux in the "near miss" sudden infant death syndrome. J Pediatr 92:73-75, 1978 21 Schey WL, Meus P, Levinsky RA, Campbell C, Replogle R: Esophageal dysmotility and the sudden infant death syndrome. Pediatr Radiol 140:73-77, 1981 22 Herbst JJ: Gastroesophageal reflux and pulmonary disease. Pediatrics 68: 132-134, 1981
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