Small Bowel Manometry (Short or Long Recording Sessions?)

The study of small bowel motility in humans iscommonly done by one of two techniques: short-termrecording in a stationary patient or long-term recordingin an ambulatory patient. To compare the diagnostic yield of short- and long-term manometricstudies of small intestinal motility, we reviewed allprolonged records performed in our center over theyears. Long-term studies that included less than 6 hr of recording during fasting or less than 5 hrduring sleep and short-term studies using the perfusedtube technique were excluded, leaving 91/121 tracingssuitable for review. We analyzed the first 3 hr of the fasting period and the first 2 hr of thepostprandial period on one occasion and the wholetracing on another; the fasting, postprandial and sleepperiod were analyzed separately. This allowed us to compare short and long recording sessions inthe same patient. The two analyses agreed in 81/91 ofthe cases. In 7/10 patients a study was diagnosed asabnormal in the short recording but was considered normal after review of the long recording,while the opposite occurred in the remaining three.Periods of sleep and fasting contributed similarly tothe change in diagnosis. In another 6 patients withequivocal abnormalities during the short period, the longperiod helped to establish the diagnosis of normalitywith confidence. Most of the improvement in thelong-term study came from extension of the studiesduring fasting to 6-7 hr from 3 hr. Long-term recordsof small bowel motility, including study during sleepenhance the diagnostic accuracy of the test. Accuracycan be improved also simply by prolonging the recording during fasting.