Understanding post-operative temperature drop in cardiac surgery: a mathematical model

Area of Science:

• Biomedical Engineering
• Thermodynamics
• Medical Physics

Background:

• Hypothermia management is critical during cardiac surgery.
• Patient re-warming can lead to dangerous core temperature drops (afterdrop).
• Understanding heat transfer dynamics is essential for safe surgical procedures.

Purpose of the Study:

• To develop a mathematical model of heat transfer during cardiac surgery cooling and re-warming.
• To investigate the phenomenon of afterdrop and its contributing factors.
• To explore strategies for mitigating afterdrop complications.

Main Methods:

• A compartmental mathematical model was developed.
• The model simulates heat transfer in core, rectal, and peripheral body regions.
• Model predictions were compared qualitatively with experimental data.

Main Results:

• The model accurately reproduced the afterdrop effect and temperature variations between body regions.
• Excess adipose tissue in peripheral and rectal regions was found to exacerbate afterdrop.
• Simulations indicated that continuous re-warming post-core-temperature-increase reduces afterdrop.

Conclusions:

• The developed model provides insights into heat transfer during cardiac surgery.
• Afterdrop is influenced by body composition and re-warming protocols.
• Continuous re-warming strategies may improve patient safety by minimizing afterdrop.