Increased intra-abdominal pressure during pneumoperitoneum decreases pancreatic perfusion in pigs: A CT perfusion study

Abstract

K. Endo , T. Sasaki , N. Sata , S. Hishikawa , H. Sugimoto , Y. Yasuda . Department of Surgery, Jichi Medical University, Tochigi Japan Department of Radiology, Jichi Medical University, Tochigi Japan 3 Center for Development of Advanced Medical Technology, Jichi Medical University, Tochigi, Japan Aim: To examine changes in pancreatic perfusion due to increased intra-abdominal pressure using CT perfusion for in vivo quantification of pancreatic perfusion. Methods: Three pigs were studied. Under general anesthesia, a 16G catheter was placed in the right jugular vein. A port was inserted in the peritoneal space and pneumoperitoneum induced to 16 mmHg. The location of the pancreas was confirmed on plain CT scan. After intravenous injection of iodinated contrast (5 ml/sec), CT scans were acquired during respiratory pause at one image per second for 60 seconds. CT perfusion was repeated five days later without pneumoperitoneum using the same protocol. Data were analyzed using the deconvolution method and Siemens VPCT software to calculate blood flow (BF), blood volume (BV), and permeability, with and without pneumoperitoneum. Results: There were no complications associated with pneumoperitoneum or contrast-enhanced CT. In the presence of pneumoperitoneum, BF and BV (expressed per 100ml of tissue) decreased from 54.99 to 15.57 ml/min and 17.93 to 2.93 ml/min, respectively. Therewas no change in permeability observed. Discussion: CT perfusion imaging allowed repeat in vivo quantification of blood flow changes in the same animal. Decreased BF and BV, measures of arterial blood flow velocity and vascular volume per unit volume of tissue, may be a direct result of increased intra-abdominal pressure. However, the lack of a consistent trend in permeability change may be due to venous drainage. Conclusions: Increased intra-abdominal pressure resulted in decreased BF and BV.