Small bowel motility: relationship between smooth muscle contraction and electroenterogram signal

A study is made to correlate the electrical and mechanical activity of the smooth muscle of the small bowel. Bioelectrical signal recording from the i ntestinal serosa (electroenterogram) comprises a slow wave (SW) and spike b urst (SB), though only the latter reflects intestinal pressure. The electro enterogram and smooth muscle pressure are simultaneously recorded in the ca nine small bowel, Spectral and time series analysis of the electroenterogra m are performed to establish those electrical parameters that best reflect intestinal pressure. The results reveal an underlying correlation between t he estimated parameters of electrical activity and smooth muscle pressure. In addition, parameters derived from the spectral techniques were closely c orrelated to pressure events in the intestine, even more so than the variab les directly acquired from the classical time domain analyses, Specifically , spectral energy above 2 Hz and mean frequency (both calculated from the b iosignal periodogram), are parameters that identify intestinal pressure. Th e extrapolation of these spectral parameters to long time periods could ser ve to define a motility index (MI) from electrical gut activity. In this co ntext, electroenterogram recording and analysis can contribute to solve pro blems inherent to manometric recording, though the need for surgical interv ention restricts electrical methods to experimental or surgical studies. (C ) 2000 IPEM. Published by Elsevier Science Ltd. All rights reserved.