To evaluate the influence of the technical problems experienced when scanning transabdominally, a comparison was made between transabdominal and intra-abdominal Doppler parameters of the aorta and the splanchnic arteries. Peroperative color duplex sonography of the abdominal aorta and the splanchnic arteries was performed on 25 patients who were undergoing abdominal vascular reconstructive surgery under stabilized standardised anaesthesia. Doppler samples and diameter measurements were taken of the aorta, celiac, common hepatic, splenic, superior and inferior mesenteric arteries, both trans- and intra-abdominally. Significantly higher velocities were recorded in the celiac artery during intra-abdominal examinations. There was a trend toward higher recorded velocities in the other vessels. There was also a significant difference in the diameter measurements of most of the vessels. The trans- and intra-abdominal results were not always equivalent. The differences were not due to technical aspects. Transabdominal duplex sonography is difficult and may not be completely accurate in detecting quantitative flow parameters in the splanchnic arteries.