The use of central venous to arterial carbon dioxide tension difference (∆PCO2) as a marker of overall perfusion even when macro-circulatory indicators appear to be normal is gaining ongoing support. This study aimed to assess the utility of ∆PCO2 in hemodynamic optimization in patients following major abdominal surgeries. Patients and methods: For this prospective observational study, 50 consecutive patients admitted to the ICU following major abdominal surgeries, with ScvO2≥70% and fitting our inclusion criteria were included once admitted (T0). Patients were separated into low ∆PCO2 group (n=27) and high ∆PCO2 group (n=23) according to a threshold of 6 mmHg at T0. Demographics, SAPS II and SOFA scores were recorded at T0, while hemodynamic and biological parameters including CI, ∆PCO2, ScvO2% and lactate level were recorded at T0, T6, T12 and T24. Results:At T0, there was a significant difference between the high and the low ∆PCO2 patients for ∆PCO2 (8.7±2.7vs4.1±1.5mmHg, P<0.001), serum lactate (2.5±1.1vs1.2±0.9mmol/L, P<0.05) and SOFA score (9(4-14)vs3(2-4), P<0.05) but not for ScvO2%. CI was significantly higher in the low ∆PCO2 group (4.4±1.2vs2.4±0.9 L/min/m2,P<0.001). From T0 to T24, CI at T6 was still significantly higher in the low ∆PCO2 group (4.3±1.0vs2.2±0.8L/min/m2 , P<0.001). At T0 and T6, ∆PCO2 and CI values were inversely correlated (T0:P<0.001 and T6:P<0.05). Conclusion: ΔPCO2 could be used to mirror inadequate tissue perfusion when ScvO2 ≥70% has already been recorded and hence provide a valuable addition to resuscitation targets in post surgical patients.