Changes in Aortic Diameter During Laparoscopic Surgery

Various haemodynamic changes are observed during laparoscopic surgery, relating to insufflation of CO2 \& patient position. Cardiac output calculations using oesophageal doppler monitoring are based on the assumption that the aortic diameter is fixed. This study aims to measure the aortic diameter at preset times during surgery using ultrasound to discover if the diameter remains the same, and hence if the assumptions made by the oesophageal monitor are reliable. Assessing the aortic diameter involves a noninvasive ultrasound measurement taken in patients electively having laparoscopic procedures at the Royal Surrey County Hospital.