World's Largest Resource for Cardiovascular Perfusion

Perfusion StaffingPerfusion Staffing
   +1 888-499-5672Login
Perfusion NewswireMain ZoneArterio-Venous Gradients of Free Energy Change for Assessment of Systemic and Splanchnic Perfusion in Cardiac Surgery Patients

Arterio-Venous Gradients of Free Energy Change for Assessment of Systemic and Splanchnic Perfusion in Cardiac Surgery Patients

Main Zone, Mobile Zone, Perfusion Zone

Objective: Adequacy of organ perfusion depends on sufficient oxygen supply in relation to the metabolic needs. The aim of this study was to evaluate the relationship between gradients of free energy change, and the more commonly used parameter for the evaluation of the adequacy of organ perfusion, such as oxygen-extraction in patients undergoing valve replacement surgery using normothermic cardiopulmonary bypass (CPB).


Methods: In 43 cardiac patients, arterial, mixed venous, and hepato-venous blood samples were taken synchronously after induction of anaesthesia (preCPB), during CPB, and 2 and 7 h after admission to the intensive care unit (ICU+2, ICU+7). Blood gas analysis, cardiac output, and hepato-splanchnic blood flow were measured. Free energy change gradients between mixed venous and arterial (-deltadeltaG(v – a)) and hepato-venous and arterial (-deltadeltaG(hv – a)) compartments were calculated.


Resutls: Cardiac index (CI) increased from 1.9 (0.7) to 2.8 (1.3) L/min/m (median, inter-quartile range) (p = 0.001), and hepato-splanchnic blood flow index (HBFI) from 0.6 (0.22) to 0.8 (0.53) L/min/m (p = 0.001). Despite increasing flow, systemic oxygen extraction increased after CPB from 24 (10)% to 35 (10)% at ICU+2 (p = 0.002), and splanchnic oxygen extraction increased during CPB from 37 (19)% to 52 (14)% (p = 0.001), and remained high thereafter. After CPB, high splanchnic and systemic gradients of free energy change gradients were associated with high splanchnic and systemic oxygen extraction, respectively (p = 0.001, 0.033, respectively).


Conclusion: Gradients of free energy change may be helpful in characterising adequacy of perfusion in cardiac surgery patients independently from measurements or calculations of data from oxygen transport.

Leave a Reply

You may also like
ECMO Zone, Perfusion Zone, Tiny Perfusion Letter

Limb Amputation Following Extracorporeal Membrane Oxygenation Therapy Among Survivors: A Nationwide Cohort Study from South Korea

In South Korea, 1.6% of ECMO survivors underwent limb amputation within 365 days after initiating ECMO therapy; however, it was not significantly associated with the 3-year all-cause mortality. Our findings warrant future studies on the impact on the quality of life and morbidity-related implications among patients who undergo limb amputation due to ECMO therapy.
Multimedia Zone, Perfusion Zone, Tiny Perfusion Letter, Uncategorized

Weaning from Cardiopulmonary Bypass, Decannulation, and Closure

Although thoracotomy or newer, less-invasive options such as peripheral cannulation are being used more frequently for minimally invasive cardiac surgery, surgical access through a median sternotomy and central cannulation remain the cornerstones of cardiac surgery and residency training. It is of utmost importance to wean the patient properly from cardiopulmonary bypass (CPB). This video tutorial discusses weaning the patient from CPB, decannulation, and closure of the sternotomy, and describes the safeguards and pitfalls of weaning from CPB.

Join TodayJoin Today