Ambulatory abdominal inductance plethysmography: towards objective assessment of abdominal distension in irritable bowel syndrome

Abstract

Background-Abdominal distension is one of the cardinal features of irritable bowel syndrome (IBS) with patients often ranking it as more intrusive than their pain or bowel dysfunction. If this symptom could be quantified accurately and reliably it would provide, for the first time, an objective way of assessing this disorder. Using the principle of inductance plethysmography we have developed a microprocessor based system capable of recording even minimal changes in girth over 24 hours and we describe its validation and establish normal ranges. Methods-Twenty four hour recordings were made in 20 healthy female volunteers (aged 23-58 years) to assess changes in abdominal girth with respect to time, posture, meals, and sleep. Normal daily activity was encouraged and meals were standardised. The feeling of abdominal distension was also assessed using a visual analogue scale. Findings-Measurement of abdominal girth using abdominal inductance plethysmography (AIP) at a static point in time showed a close relationship with that measured using a tape measure (rho=0.8910, p<0.001). Furthermore, girth was significantly greater both in the sitting and standing postures compared with lying (p<0.01). Measurement over a 24 hour period showed that girth was significantly greater at the end compared with the beginning of the day, and ingestion of a standard meal also increased its value (p<0.05). Sleep was associated with a reduction in girth (p<0.05). Conclusions-AIP promises to add an objective dimension to the assessment of IBS which could prove invaluable in clinical trials. Furthermore, it should aid research into the pathogenesis of this symptom for which no satisfactory explanation has yet emerged. (Gut 2001;48:216-220)

Changing face of irritable bowel syndrome

“…Distension, often the most distressing "gas"-related symptom in IBS, has, until recently, been assumed to represent a disturbance of perception, as apparently objective tests of abdominal volume failed to detect any increase in IBS [16] . This assumption has now been questioned [17] and it may well come to pass that more detailed studies of changes in distension over time [18] may detect significant diurnal variations in girth in IBS. While the balance of evidence suggests that intestinal gas production is not abnormal in IBS, one can visualize how relatively local changes in the gas content could lead to symptoms, given the aforementioned intrinsic abnormality of gas transport [19] and the hypersensitivity to intraluminal gas that are known to occur in IBS [20] .…”

What Is New in Rome IV

“…49 The addition of distension also reflects the findings with new technologies such as abdominal plethysmography. 59 Rome IV recognizes that patients may also report symptoms of mild abdominal pain and/or minor bowel movement abnormalities. Opioid induced constipation (OIC) is one of the new disorders now included in Rome IV.…”

Clinical trial: the effects of a fermented milk product containing Bifidobacterium lactis DN‐173 010 on abdominal distension and gastrointestinal transit in irritable bowel syndrome with constipation

“…The technique we used is described elsewhere, 18,42,43 but briefly, it works on the principle that a loop of wire forms an inductor, the inductance of which is dependent on the area enclosed by the loop. For AIP, the wire is sewn into a band of elastic fabric (8.5 cm wide) in a zig-zag fashion to allow for expansion (Respitrace inductive sensor; Ambulatory Monitoring Inc., New York, NY, USA) and is worn around the abdomen, similar to a belt.…”

“…18,42,43 Each subject was given a further paper diary in which to record, at 'hourly intervals' the severity of their bloating (0-5 scale) and the time and content of any oral intake (both solids and liquids). The subjects were then allowed to leave the laboratory and were asked to maintain their usual daily activities until they returned for removal of the AIP device 24 h later (day 0).…”