Myoelectric assessment of large bowel viability: an experiment in dogs.

OBJECTIVE

To design a device for myoelectric assessment of intestinal ischaemia and compare it with every day surgical experience and Doppler signals recorded on the bowel wall.

DESIGN

Experimental study.

SETTING

Thessaloniki university hospital, Greece.

MATERIAL

12 adult mongrel dogs.

INTERVENTIONS

On the first day the large intestine was devascularised for a length of 20 cm, 5 cm away from the ileocaecal valve, and the threshold of the electric stimulus (mA) required to produce a contraction of the normal large bowel was recorded. On the second day, measurements were made on the ischaemic segment of the large bowel at 0.5 cm intervals. Bowel resection and anastomoses were done at the stimulus level of 40 mA.

RESULTS

The mean (SD) stimulus threshold of the normal large intestine was 12.2 mA. The necrotic intestine demanded current stimulus of 100 mA or failed to contract. On the eighth postoperative day the animals were killed to assess anastomotic healing. Of the 12 anastomoses made at the 40 mA stimulus point, only one ruptured. The 40 mA limit of the stimulus level seems to be of value in assessments of bowel viability in vivo.

CONCLUSION

The use of a personal computer as a read out device makes myoelectric analysis easier and more reliable in the assessment of intestinal viability. This method may have a clinical application.