Amy Uber1, Anne V Grossestreuer2, Catherine E Ross3, Parth V Patel2, Ambica Trehan2, Michael W Donnino4, Katherine M Berg5. 1. Department of Emergency Medicine, Beth Israel Deaconess Medical Center, 1 Deaconess Road, Boston, MA 02115, USA; Michigan State University College of Human Medicine, 15 Michigan Street NE, Grand Rapids, MI 49503, USA. 2. Department of Emergency Medicine, Beth Israel Deaconess Medical Center, 1 Deaconess Road, Boston, MA 02115, USA. 3. Division of Medicine Critical Care, Department of Medicine, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA. 4. Department of Emergency Medicine, Beth Israel Deaconess Medical Center, 1 Deaconess Road, Boston, MA 02115, USA; Department of Medicine, Division of Critical Care, Beth Israel Deaconess Medical Center, 1 Deaconess Road, Boston, MA 02115, USA. 5. Department of Medicine, Division of Critical Care, Beth Israel Deaconess Medical Center, 1 Deaconess Road, Boston, MA 02115, USA. Electronic address: kberg@bidmc.harvard.edu.
Abstract
AIM: Limited data suggests low oxygen consumption (VO2), driven by mitochondrial injury, is associated with mortality after cardiac arrest. Due to the challenges of measurement in the critically ill, post-arrest metabolism remains poorly characterized. We monitored VO2, carbon dioxide production (VCO2) and the respiratory quotient (RQ) in post-arrest patients and explored associations with outcome. METHODS: Using a gas exchange monitor, we measured continuous VO2 and VCO2 in post- arrest patients treated with targeted temperature management. We used area under the curve and medians over time to evaluate the association between VO2, VCO2, RQ and the VO2:lactate ratio with survival. RESULTS: In 17 patients, VO2 in the first 12 h after return of spontaneous circulation (ROSC) was associated with survival (median in survivors 3.35 mL/kg/min [2.98,3.88] vs. non-survivors 2.61 mL/kg/min [2.21,2.94], p = .039). This did not persist over 24 h. The VO2:lactate ratio was associated with survival (median in survivors 1.4 [IQR: 1.1,1.7] vs. non-survivors 0.8 [IQR: 0.6,1.2] p < 0.001). Median RQ was 0.66 (IQR 0.63,0.70) and 71% of RQ measurements were <0.7. Patients with initial RQ < 0.7 had 17% survival versus 64% with initial RQ > 0.7 (p = .131). VCO2 was not associated with survival. CONCLUSIONS: There was a significant association between VO2 and mortality in the first 12 h after ROSC, but not over 24 h. Lower VO2: lactate ratio was associated with mortality. A large percentage of patients had RQs below physiologic norms. Further research is needed to explore whether these parameters could have true prognostic value or be a potential treatment target.
AIM: Limited data suggests low oxygen consumption (VO2), driven by mitochondrial injury, is associated with mortality after cardiac arrest. Due to the challenges of measurement in the critically ill, post-arrest metabolism remains poorly characterized. We monitored VO2, carbon dioxide production (VCO2) and the respiratory quotient (RQ) in post-arrestpatients and explored associations with outcome. METHODS: Using a gas exchange monitor, we measured continuous VO2 and VCO2 in post- arrestpatients treated with targeted temperature management. We used area under the curve and medians over time to evaluate the association between VO2, VCO2, RQ and the VO2:lactate ratio with survival. RESULTS: In 17 patients, VO2 in the first 12 h after return of spontaneous circulation (ROSC) was associated with survival (median in survivors 3.35 mL/kg/min [2.98,3.88] vs. non-survivors 2.61 mL/kg/min [2.21,2.94], p = .039). This did not persist over 24 h. The VO2:lactate ratio was associated with survival (median in survivors 1.4 [IQR: 1.1,1.7] vs. non-survivors 0.8 [IQR: 0.6,1.2] p < 0.001). Median RQ was 0.66 (IQR 0.63,0.70) and 71% of RQ measurements were <0.7. Patients with initial RQ < 0.7 had 17% survival versus 64% with initial RQ > 0.7 (p = .131). VCO2 was not associated with survival. CONCLUSIONS: There was a significant association between VO2 and mortality in the first 12 h after ROSC, but not over 24 h. Lower VO2: lactate ratio was associated with mortality. A large percentage of patients had RQs below physiologic norms. Further research is needed to explore whether these parameters could have true prognostic value or be a potential treatment target.
Authors: Jerry P Nolan; Robert W Neumar; Christophe Adrie; Mayuki Aibiki; Robert A Berg; Bernd W Böttiger; Clifton Callaway; Robert S B Clark; Romergryko G Geocadin; Edward C Jauch; Karl B Kern; Ivan Laurent; W T Longstreth; Raina M Merchant; Peter Morley; Laurie J Morrison; Vinay Nadkarni; Mary Ann Peberdy; Emanuel P Rivers; Antonio Rodriguez-Nunez; Frank W Sellke; Christian Spaulding; Kjetil Sunde; Terry Vanden Hoek Journal: Resuscitation Date: 2008-10-28 Impact factor: 5.262