G Muller1, E Mercier2, P Vignon3,4, M Henry-Lagarrigue5, T Kamel1, A Desachy6, V Botoc7, G Plantefève8, J P Frat9, F Bellec10, J P Quenot11,12, P F Dequin2, T Boulain1. 1. Medical-Surgical Intensive Care Unit, Regional Hospital Centre, Orléans, France. 2. Medical Intensive Care Unit, University Hospital, Tours, France. 3. Medical-Surgical Intensive Care Unit, University Hospital, Limoges, France. 4. CIC-P 1435, INSERM U1092, Limoges, France. 5. Medical-Surgical Intensive Care Unit, District Hospital Centre, La Roche-sur-Yon, France. 6. Medical-Surgical Intensive Care Unit, District Hospital Centre, Angoulême, France. 7. Medical-Surgical Intensive Care Unit, District Hospital Centre, Saint-Malo, France. 8. Medical-Surgical Intensive Care Unit, District Hospital Centre, Argenteuil, France. 9. Medical Intensive Care Unit, University Hospital, Poitiers, France. 10. Medical-Surgical Intensive Care Unit, District Hospital Centre, Montauban, France. 11. Medical Intensive Care Unit, University Hospital, Dijon, France. 12. Lipness Team, INSERM Research Centre UMR 866 and LabExLipSTIC, University of Burgundy, Dijon, France.
Abstract
OBJECTIVE: To investigate the prognostic significance of central venous-to-arterial carbon dioxide difference (cv-art CO 2 gap) during septic shock in patients with and without impaired cardiac function. METHODS: We performed a prospective cohort study in 10 French intensive care units. Patients suffering from septic shock were assigned to the impaired cardiac function group ('cardiac group', n =123) if they had atrial fibrillation (AF) and/or left ventricular ejection fraction (LVEF) <50% at study entry and to the non-cardiac group ( n =240) otherwise. RESULTS: Central venous and arterial blood gases were sampled every 6 h during the first 24 h to calculate cv-art CO 2 gap. Patients in the cardiac group had a higher cv-art CO 2 gap [at study entry and 6 and 12 h (all P <0.02)] than the non-cardiac group. Patients in the cardiac group with a cv-art CO 2 gap >0.9 kPa at 12 h had a higher risk of day 28 mortality (hazard ratio=3.18; P =0.0049). Among the 59 patients in the cardiac group with mean arterial pressure (MAP) ≥65 mm Hg, central venous pressure (CVP) ≥8 mm Hg and central venous oxygen saturation (ScvO 2 ) ≥70% at 12 h, those with a high cv-art CO 2 gap (>0.9 kPa; n =19) had a higher day 28 mortality (37% vs. 13%; P =0.042). In the non-cardiac group, a high cv-art CO 2 gap was not linked to a higher risk of day 28 death, whatever the threshold value of the cv-art CO 2 gap. CONCLUSION: Patients with septic shock and with AF and/or low LVEF were more prone to a persistent high cv-art CO 2 gap, even when initial resuscitation succeeded in normalizing MAP, CVP, and ScvO 2 . In these patients, a persistent high cv-art CO 2 gap at 12 h was significantly associated with higher day 28 mortality.
OBJECTIVE: To investigate the prognostic significance of central venous-to-arterial carbon dioxide difference (cv-art CO 2 gap) during septic shock in patients with and without impaired cardiac function. METHODS: We performed a prospective cohort study in 10 French intensive care units. Patients suffering from septic shock were assigned to the impaired cardiac function group ('cardiac group', n =123) if they had atrial fibrillation (AF) and/or left ventricular ejection fraction (LVEF) <50% at study entry and to the non-cardiac group ( n =240) otherwise. RESULTS: Central venous and arterial blood gases were sampled every 6 h during the first 24 h to calculate cv-art CO 2 gap. Patients in the cardiac group had a higher cv-art CO 2 gap [at study entry and 6 and 12 h (all P <0.02)] than the non-cardiac group. Patients in the cardiac group with a cv-art CO 2 gap >0.9 kPa at 12 h had a higher risk of day 28 mortality (hazard ratio=3.18; P =0.0049). Among the 59 patients in the cardiac group with mean arterial pressure (MAP) ≥65 mm Hg, central venous pressure (CVP) ≥8 mm Hg and central venous oxygen saturation (ScvO 2 ) ≥70% at 12 h, those with a high cv-art CO 2 gap (>0.9 kPa; n =19) had a higher day 28 mortality (37% vs. 13%; P =0.042). In the non-cardiac group, a high cv-art CO 2 gap was not linked to a higher risk of day 28 death, whatever the threshold value of the cv-art CO 2 gap. CONCLUSION: Patients with septic shock and with AF and/or low LVEF were more prone to a persistent high cv-art CO 2 gap, even when initial resuscitation succeeded in normalizing MAP, CVP, and ScvO 2 . In these patients, a persistent high cv-art CO 2 gap at 12 h was significantly associated with higher day 28 mortality.