Membrane and bubble oxygenators compared by preservation of myocardial function

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Medical Device Technology

Background:

• Membrane oxygenators are reported to offer superior preservation of various organs compared to bubble oxygenators.
• Evaluating the impact of different oxygenator types on cardiac function is crucial for cardiopulmonary bypass procedures.

Purpose of the Study:

• To compare the preservation of ventricular function in isolated canine hearts perfused with either membrane or bubble oxygenators.
• To assess the effects of bubble (Temptrol) and membrane (Lande-Edwards) oxygenators on myocardial contractile force, velocity, and compliance.

Main Methods:

• Isolated canine hearts were perfused for three hours using either bubble or membrane oxygenators.
• Isovolumic tests were employed to measure ventricular contractile force, velocity, and compliance.
• Ventricular function was assessed by comparing post-perfusion values to initial measurements, expressed as percentages.

Main Results:

• Hearts perfused with membrane oxygenators showed a trend towards better preservation of contractile force and velocity compared to bubble oxygenators.
• Ventricular compliance was notably higher in hearts perfused with membrane oxygenators, approaching statistical significance (P < 0.1).
• No significant differences in terminal ventricular weight (oedema index) were observed between the two groups.

Conclusions:

• Membrane oxygenators may provide comparable or superior protection to the myocardium as they do for other organs during cardiopulmonary bypass.
• The findings suggest that membrane oxygenators, despite similar cost and simplicity to conventional types, could offer advantages for myocardial preservation.