Combining central venous-to-arterial partial pressure of carbon dioxide difference and central venous oxygen saturation to guide resuscitation in septic shock

Purpose: Central venous oxygen saturation (Scvo(2)) is a useful therapeutic target when treating septic shock. We hypothesized that combining Scvo(2) and central venous-to-arterial partial pressure of carbon dioxide difference (Delta Pco(2)) may provide additional information about survival. Materials and Methods: We performed a retrospective analysis of 172 patients treated for septic shock. All patients were treated using goal-directed therapy to achieve Scvo(2) >= 70%. After 6 hours of treatment, we divided patients into 4 groups based on Scvo(2) (<70% or >= 70%) and Delta Pco(2) (<6 mm Hg or >= 6 mm Hg). Results: Overall, 28-day mortality was 35.5%. For patients in whom the Scvo(2) target was not achieved at 6 hours, mortality was 50.0%, compared with 29.5% in those in whom Scvo(2) exceeded 70% (P = .009). In patients with Scvo(2) >= 70%, mortality was lower if. Delta Pco(2) was <6 mm Hg than if. Delta Pco(2) was >= 6 mm Hg (56.1% vs 16.1%, respectively; P < .001) and 6-hour lactate clearance was superior (0.01 +/- 0.61 vs 0.21 +/- 0.31, respectively; P = .016). Conclusions: The combination of Scvo(2) and Delta Pco(2) appears to predict outcome in critically ill patients resuscitated from septic shock better than Scvo(2) alone. Patients who meet both targets appear to clear lactate more efficiently. (C) 2013 Elsevier Inc. All rights reserved.