Direct electrical stimulation for constipation treatment after spinal cord injury

The effect of direct electrical stimulation on colonic transit and manometric recordings following a spinal cord injury (SCI) at T4 were assessed in five adult male cats. Animals were evaluated under three conditions: before SCI, after SCI, and after SCI with direct electrical stimulations of the colon. Electrical stimulation protocols compared pulse durations of 0.1 and 1.0 ms, frequencies of 10 and 40 pps, and stimulating currents ranging from 0-50 mA. Colonic transit times were determined for each of the three animal conditions. SCI was found to prolong (P<0.05) transit when compared to the transit before SCI. Electrical stimulation following SCI was found to decrease transit to values not significantly different from those before SCI. Manometric defecation patterns were recorded for PreSCI, SCI, and SCI+stim. Using a criterion based scale, it was possible to identify each type of spontaneous and stimulation induced contraction. Before SCI the most frequent event was a colonic contraction (38%) compared to an abdominal contraction (38%) after SCI+stim. The number of phasic contractions/hr was determined in the fasting and postprandial states and was not found to be significantly different. These findings demonstrate direct electrical stimulation of the colon following SCI improves colonic transit and does not appear to affect phasic colonic activity in this animal model.