Critical Oxygen Delivery: The Crux of Bypass with a SpecialLook at the Microcirculation

Spiess BD

 
The microcirculation can be defined as those vascularstructures where respiratory gas flux occurs. These are generallythe arterioles, venules, and capillaries. Larger vascularconduits tend to have thicker walls, are at considerable distancefrom cellular sites of oxygen utilization, and therefore contributelittle to oxygen flux . The microcirculation is complex, nota simple straight line of parallel groups of pipes with unidirectionalflow. Rather, the complex network has most vascularstructures not open (held in reserve) and often has bidirectionalflow. Understanding the movement of O 2 , CO 2 , and other gaseswithin this network has only recently been the center of focusedresearch. The cardiopulmonary bypass machine is meant to keepthe microcirculation normal, but research is demonstrating majorchanges within. This review looks at what is known today inspontaneously perfusing animals as well as early findings notingdifferences in cardiopulmonary bypass. We, as yet, do not understandall the mechanisms involved in the changes of the microcirculationso thoughts regarding future areas for research are discussed .
 
References:Spiess BD Critical Oxygen Delivery: The Crux of Bypass with a SpecialLook at the Microcirculation JECT 2011;43:16-Oct
 
Institution(s):Virginia Commonwealth University Medical Center, Richmond, VA
 
Category:Abstract