Electrogastrography in chronic intestinal pseudoobstruction.

This study aimed to characterize the disturbance of gastric electrical control activity in chronic intestinal pseudoobstruction (CIP) and to determine whether surface electrogastrography (EGG) could be used to diagnose the presence and type of CIP. Gastric electrical control activity was recorded for 30 min in each of the fasting and fed states by EGG in 14 adults with CIP proven on clinical, radiological, and histological grounds, and in 14 age- and sex-matched controls. Electrical activity was recorded from four pairs of Ag-AgCl bipolar skin electrodes, the captured signal amplified and digitalized, and running spectral analysis performed. The dominant frequency and power of spectrum were calculated using a sequence of computerized algorithms. Results were correlated with the known pathological diagnoses [visceral myopathy (M), N = 7; visceral neuropathy (N), N = 4; undifferentiated (U), N = 3]. Dysrhythmias were present in 13 of 14 patients. Tachygastria (electrical control activity frequency >5 cycles/minute) and a normal amplitude response to food, was seen in five patients (N = 4, U = 1). Irregular continuous activity without a dominant frequency or bradyarrhythmia, together with a diminished electrical response activity (ERA) to food, were found in six patients (M = 5, U = 1). Mixed abnormalities were seen in two patients (M = 1, U = 1), and normal activity with a clear dominant frequency of 3 cycles/minute was present in only one patient (M = 1). This noninvasive technique is both sensitive and specific in providing evidence of a dysrhythmia in patients with CIP and discriminates between primary pathologies. EGG may prove diagnostically useful in these disorders and may provide insight into the disturbance of electrical control activity.