Can Partial Oxygen Pressure Of Urine Be An Indicator For Tissue Perfusion? Review

The main purpose of advanced monitorisation is to detect hypoperfusion before any irreversible damage. However, none of the advanced monitorisation procedures focusing only on the hemodynamics and blood gas parameters are sufficient to estimate tissue perfusion adequately. As low urine partial oxygen pressure (PuO2 ) is an indicator for medullary hypoperfusion, PuO2 measurement is one of the promising markers for early detection of hypoperfusion. Based on this hypothesis, we had designed a study to evaluate the use of PuO2 together with routine systemic tissue perfusion parameters in patients undergoing open-heart surgery with extracorporeal circulation. Fifty patients undergoing elective coronary artery bypass graft surgery had included. In addition to the routine hemodynamic monitorization; cardiac output (CO), Pv-aCO2 , blood, and urine gas analysis were performed at 180th, 360th, and 540th minutes postoperatively, and creatinine was measured repetitively postoperatively. None of the patients developed any hemodynamic event related to hypoperfusion or acute renal injury. No correlation between hemodynamic and blood gas parameters with PuO2 could be shown in this study. In conclusion, further studies on patients with hypoperfusion and transient renal ischemia may correctly resolve the correlation