Gas exchange devices (traditionally called oxygenators) are designed to
oxygenate and ventilate the blood. “Rated flow” is the amount of desaturated
(75%) venous blood with hemoglobin of 12 gm/dL that can be nearly fully
saturated (95%) per minute.[ 4 ] The maximal oxygen delivery (typically 4-5 mL
O2/dL), the amount of oxygen delivered per minute when running at rated flow, is
calculated using the difference in oxygen content between the inlet and outlet
blood. For example, a rated flow of 2 L/min reflects a maximum oxygen delivery
of 100 mL O2/min.
The gas blown through the device, across the membrane, is called the
sweep gas. The sweep gas is usually 100% oxygen, though occasionally carbon
dioxide is added at small amounts (5%) due to the efficiency of carbon dioxide
marcin
(Marcin)
#1