Eur J Anaesthesiol 2014; 31:361–362
INVITED COMMENTARY
Two goals, one shot at survival: DPCO2 and ScvO2 Alison Sheehan and Malachy Columb
European Journal of Anaesthesiology 2014, 31:361–362
This Invited Commentary accompanies the following original article: Mallat J, Pepy F, Lemyze M, et al. Central venous-toarterial carbon dioxide pressure difference in early resuscitation from septic shock. A prospective observational study. Eur J Anaesthesiol 2014; 31: 371–380.
Septic shock is a major healthcare problem with a mortality rate of 46% in patients with arterial hypotension and a blood lactate concentration more than 4 mmol l 1.1 Since the publication of the Rivers article in 2001,2 much clinical research has been performed on early goaldirected therapy and the Surviving Sepsis Campaign has published protocolised quantitative resuscitation guidelines to be initiated as soon as hypoperfusion is identified.1 The normalisations of central venous oxygen saturation (ScvO2) and blood lactate can be combined as a resuscitation endpoint with a proven reduction in mortality.3 However, persistent tissue hypoperfusion and mitochondrial failure may occur in the presence of normal or increased ScvO2, which may limit the reliance on it in clinical practice. Central and mixed venous-toarterial CO2 partial pressure differences (DPCO2) have been used to guide treatment for shock. Several studies have shown that mixed venous CO2 is inversely proportional to cardiac output for both septic and non-septic shock,4,5 and a recent retrospective study by Du et al.6 on 172 patients with septic shock found that in patients who were resuscitated to a ScvO2 more than 70% and DPCO2 less than 0.8 kPa, mortality was lower and 6 h lactate clearance was superior. In the European Journal of Anaesthesiology this month, Mallat et al.7 present their findings from a single-centre prospective observational cohort study which examined the behaviours of mixed venous DPCO2 in relation to
cardiac index (CI) and the percentage decrease in blood lactate in patients with early septic shock. The aim was to compare patients who achieved a normal DPCO2 of less than 0.8 kPa within 6 h of treatment with those who failed and remained with a high DPCO2 more than 0.8 kPa. They recruited 88 patients with septic shock over a 21-month period and the overall 28-day mortality for the cohort was 55%. All patients were mechanically ventilated, underwent CI monitoring with a transpulmonary thermodilution device (PiCCO; Pulsion Medical System, Munich, Germany) and were enrolled in the study within a median time of 1.5 h from the diagnosis of septic shock. After 6 h of resuscitation with endpoints as recommended by the Surviving Sepsis Campaign,1 patients who achieved a normal DPCO2 had significant improvements in mean arterial pressure (MAP), arterial pH, CI, ScvO2, and oxygen delivery (DO2) as well as a greater percentage decrease in blood lactate. This was also associated with a significant reduction in 28-day mortality (42 vs. 75%). Patients who were resuscitated within 6 h to both endpoints (ScvO2 >70% and DPCO2
INVITED COMMENTARY
Two goals, one shot at survival: DPCO2 and ScvO2 Alison Sheehan and Malachy Columb
European Journal of Anaesthesiology 2014, 31:361–362
This Invited Commentary accompanies the following original article: Mallat J, Pepy F, Lemyze M, et al. Central venous-toarterial carbon dioxide pressure difference in early resuscitation from septic shock. A prospective observational study. Eur J Anaesthesiol 2014; 31: 371–380.
Septic shock is a major healthcare problem with a mortality rate of 46% in patients with arterial hypotension and a blood lactate concentration more than 4 mmol l 1.1 Since the publication of the Rivers article in 2001,2 much clinical research has been performed on early goaldirected therapy and the Surviving Sepsis Campaign has published protocolised quantitative resuscitation guidelines to be initiated as soon as hypoperfusion is identified.1 The normalisations of central venous oxygen saturation (ScvO2) and blood lactate can be combined as a resuscitation endpoint with a proven reduction in mortality.3 However, persistent tissue hypoperfusion and mitochondrial failure may occur in the presence of normal or increased ScvO2, which may limit the reliance on it in clinical practice. Central and mixed venous-toarterial CO2 partial pressure differences (DPCO2) have been used to guide treatment for shock. Several studies have shown that mixed venous CO2 is inversely proportional to cardiac output for both septic and non-septic shock,4,5 and a recent retrospective study by Du et al.6 on 172 patients with septic shock found that in patients who were resuscitated to a ScvO2 more than 70% and DPCO2 less than 0.8 kPa, mortality was lower and 6 h lactate clearance was superior. In the European Journal of Anaesthesiology this month, Mallat et al.7 present their findings from a single-centre prospective observational cohort study which examined the behaviours of mixed venous DPCO2 in relation to
cardiac index (CI) and the percentage decrease in blood lactate in patients with early septic shock. The aim was to compare patients who achieved a normal DPCO2 of less than 0.8 kPa within 6 h of treatment with those who failed and remained with a high DPCO2 more than 0.8 kPa. They recruited 88 patients with septic shock over a 21-month period and the overall 28-day mortality for the cohort was 55%. All patients were mechanically ventilated, underwent CI monitoring with a transpulmonary thermodilution device (PiCCO; Pulsion Medical System, Munich, Germany) and were enrolled in the study within a median time of 1.5 h from the diagnosis of septic shock. After 6 h of resuscitation with endpoints as recommended by the Surviving Sepsis Campaign,1 patients who achieved a normal DPCO2 had significant improvements in mean arterial pressure (MAP), arterial pH, CI, ScvO2, and oxygen delivery (DO2) as well as a greater percentage decrease in blood lactate. This was also associated with a significant reduction in 28-day mortality (42 vs. 75%). Patients who were resuscitated within 6 h to both endpoints (ScvO2 >70% and DPCO2
