Increasing Cardiac Output by Epinephrine After Cardiac Surgery: Effects on Indocyanine Green Plasma Disappearance Rate and Splanchnic Microcirculation

Objective: The effects of increasing cardiac output by epinephrine on indocyanine green plasma disappearance rate (ICG-PDR) and gastric mucosal PCO2 (PRCO2) were studied as indicators of splanchnic microcirculation.Design: A prospective clinical study.Setting: Intensive care unit of a university hospital.Participants: With ethics approval and written consent, 12 elective cardiac surgical patients (5 female, 7 male, 71 ± 8 years) were studied.Interventions: Patients underwent pulmonary artery and left atrial catheterization for clinical indications. Measurements were made at intensive care unit admission and 1 hour after (increased) epinephrine treatment. Mean epinephrine dose was changed from 0.02 to 0.08 μg/kg/min.Results: Heart rate significantly increased from 97 ± 11 to 106 ± 12 beat/min. Central venous (10 ± 3 v 10 ± 4 mmHg) and left atrial (10 ± 5 v 11 ± 5 mmHg) pressures were unchanged. Cardiac index and stroke volume index significantly increased from 2.7 ± 0.5 to 3.2 ± 0.5 L/min/m2 and from 28 ± 6 to 31 ± 5 mL/m2, respectively. Although systemic O2 delivery and O2 consumption significantly increased, ICG-PDR did not change significantly (ie, from 18.0% ± 5.6% to 19.5% ± 6.4% per minute). PRCO2 and PCO2 gap (difference between regional and end-tidal PCO2) significantly increased from 5.4 ± 1.0 to 5.9 ± 1.1 kPa and 1.2 ± 0.8 to 1.5 ± 0.7 kPa, respectively.Conclusion: Increasing cardiac output by epinephrine in patients after cardiac surgery was not associated with a change in flow-dependent liver function but a deterioration in gastric mucosal perfusion.