Changes in intra-abdominal pressure in patients undergoing coronary artery bypass grafting and valve replacement

The aim of the present study was to analyze the changes in intra-abdominal pressure in patients undergoing different cardiac procedures with extracorporeal circulation (ECC). Patients and methods: IAP was measured in 100 patients undergoing CABG or valve replacement (VR) with ECC. IAP was measured in the urinary bladder at six measurement points: 1/ just before anaesthesia, 2/ 10 minutes after ECC; 3/ just after surgery, 4/ one hour after the completed procedure, 5/ 6 hours after the completed procedure, 6/ 18 hours after the procedure. Additionally, IAP was correlated with heart rate (HR), mean artery pressure (MAP and central venous pressure (CVP). According to cardiac procedure, patients were divided into two groups: A/ CABG, B/ VR. Results: In all patients, ECC resulted in an increase in IAP from 2nd to 6th measurement points. There were significant correlations between: IAP and BMI (p < 0.001; R = 0.3487), IAP and the duration of: anaesthesia and surgery from 2nd to 6th, ECC from 4th to 6th and aorta clamping from 3rd to 6th measurement points. In groups A and B, IAP increased from 2nd to 6th measurement points. IAP correlated with a fluid balance, BMI, duration of anaesthesia, duration of ECC and aorta clamping time. Additionally, there were strong overall correlation between IAP and CVP. Conclusions: 1/ ECC resulted in increase in IAP; 2/ IAP correlated with BMI, 3/ IAP elevation depended on duration of: anaesthesia, surgery, ECC and aorta clamping, 4/ fluid balance had a strong impact on IAP, 5/ IAP correlated with CVP.