In vivo behavior of microporous membrane oxygenators in cardiac surgery.

Abstract

Hollowfiber membrane oxygenators currently in the market are tested by manufacturers with bovine blood in normothermia and with a hemoglobin levels slightly higher than those managed under real conditions in cardiac surgery (where hemodilution is used). To measure the performance of oxygenators, several parameters are evaluated and reflected in graphs by the industry, the 4 most common parameters shown are: Oxygen transfer (Transfer O2), Carbon dioxide transfer (CO2 transfer), Heat exchanger performance factor (Transf. Temp) and Pressure drop (Delta P). The purpose of this study was to represent the graphical slopes of the oxygenator performance in vivo in real conditions (human blood, lower temperature, lower hemoglobin) and compare them with the reference slopes provided by the manufacturers of the oxygenators to highlight the possible differences in the informational reference graphs of oxygenator performance in vivo vs. in vitro. 5 types of hollow fiber membrane oxygenator were anylized and Data was collected from 52 patients (35 adults, 17 infants). Pearson coeficient correlation was used to relate these variables. A p-value was considered statistically significant if it was less than (p <0.05).