Y. El Dsouki and I. Condello: J Extra Corpor Technol 2025, 57, 137--146 145
Table 4. Temperature-based oxygen delivery and flow threshold example.
Temperature(° C) |
Metabolic rate reduction(%) Recommended DO 2( mL / min / m 2) |
Flow adjustments |
37 ° C( normothermic) |
0 % |
286 |
Standard perfusion flow |
32 ° C( mild hypothermia) |
~ 20 % |
220 |
Reduce flow ~ 10--15 % |
28 ° C( moderate hypothermia) |
~ 50 % |
180 |
Reduce flow ~ 30 % |
22 ° C( deep hypothermia) |
~ 75 % |
120 |
Reduce flow ~ 50 % |
18 ° C( deep hypothermic circulatory arrest) |
~ 85 % |
80 |
Circulatory arrest or very low flow |
Table 5. Integration of temperature, DO 2, and CO 2 management threshold example.
Temperature(° C) |
pH strategy |
DO 2 optimization |
CO 2 strategy |
37 ° C |
Alpha-stat |
High flow, normothermia |
Standard CO 2 removal |
32 ° C |
Alpha-stat |
Moderate-flow, reduced VO 2 |
Moderate CO 2 removal |
28 ° C |
Alpha-stat or pH-stat |
Lower flow, adjusted DO 2 |
Adjusted CO 2 sweep |
22 ° C |
pH-stat |
Minimal flow to match metabolism |
High CO 2 sweep to maintain pH |
18 ° C |
pH-stat |
Low-flow or arrest |
Max CO 2 sweep to prevent acidosis |
Conclusions
The introduction of an automated temperature management algorithm for CPB would represent a significant advancement in cardiac surgery. By reducing human error associated with manual temperature adjustments, this algorithm could enhance patient safety and contribute to more consistent surgical outcomes. It would also promote standardization across CPB procedures, ensuring a uniform approach to managing patient temperature during surgeries, which is critical for the reproducibility of successful outcomes. Despite its potential benefits, the adoption of such an advanced system poses challenges. It would require rigorous validation to ensure its reliability and effectiveness across various clinical settings. Additionally, integrating this technology into existing healthcare practices would necessitate substantial training and adaptation by medical professionals.
Funding This research received no external funding.
Conflicts of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Data availability statement There are no new data associated with this article.
Author contribution statement
Conceptualization, methodology, writing-- original draft preparation, Y. E. D. and I. C.; original draft revision and investigation, Y. E. D. and I. C.
Ethics approval
As noted in the manuscript, IRB approval was not applicable for this study. However, we have included a section discussing the ethical considerations surrounding automation in surgical environments, including human oversight, accountability, training, and alarm fatigue.
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