Objective:To assess the incidence of intra-abdominal hypertension and splanchnic hypoperfusion after a major abdominal surgery. Design: Observational, prospective cohort study. Setting:ICU, Surgical Department I, St. Anna’s University Hospital, Brno. Material and Methods: Patients undergoing major abdominal surgery were eligible. Intra-abdominal pressure (IAP), gastric tonometry (GT) and arterial blood gases were measured postoperatively at the ICU (T0) and then at T1, T6, T12, T18, T24 . At the same time points abdominal perfusion pressure (APP) and CO2gap were calculated. At T1 and T6, indocyanine green clearance (ICG-PDR) was measured non-invasively. Data – median (range). Statistics: nonparametric ANOVA for repeated measurements was used, P < 0.05 considered significant. Results: Thirteen patients (9 men, 4 women) aged 69 (35;78) underwent an uncomplicated operation in a combined anaesthesia. The epidural analgesia was given postoperatively to all patients. At T0 IAP was 8 (1; 18) mm Hg and did not change significantly during the study. Only 3 patients had increased IAP > 12 mm Hg at some time point during the study, IAP > 20 mm Hg was not measured. APP at T0 was 87 (62; 105) mm Hg and significantly decreased during the study (P < 0.001). pCO2 gap was -0.1 (-1.6; 2.9) kPa and did not change significantly. Only 2 patients had pathological values of ICG-PDR < 18 %/min. The ICU stay of all patients was uneventful except for one patient who died of malignant arrhythmia on Day 4. Conclusion: Patients after the uncomplicated major abdominal surgery seldom experience a clinically significant IAP increase. Hypoperfusion of the gastric mucosa and the liver compromise is also very rare.

        Key words: abdominal surgery – intra-abdominal pressure – gastric tonometry – ICG clearance