Optimal temperature management in aortic arch surgery: A systematic review and network meta-analysis

Area of Science:

• Cardiovascular Surgery
• Medical Hypothermia
• Aortic Arch Surgery

Background:

• New temperature management strategies for moderate and mild hypothermic circulatory arrest during aortic arch surgery are gaining traction over profound cooling.
• Comparisons across all temperature levels have been limited, necessitating a comprehensive analysis.

Approach:

• A network meta-analysis was conducted, directly and indirectly comparing deep hypothermic circulatory arrest (DHCA) (≤20°C), moderate hypothermic circulatory arrest (MHCA) (20.1-25°C), and mild hypothermic circulatory arrest (mild HCA) (≥25.1°C).
• A systematic literature search identified 34 studies (12,370 patients) reporting clinical outcomes after aortic arch surgery using these temperature management strategies.
• Primary outcome was operative mortality; secondary outcomes included postoperative stroke and acute kidney failure (AKI).

Key Points:

• Deep hypothermic circulatory arrest (DHCA) was linked to a significantly higher incidence of postoperative stroke compared to MHCA and mild HCA.
• Both DHCA and MHCA were associated with increased operative mortality relative to mild HCA.
• Analysis of randomized and propensity score-matched studies confirmed an elevated stroke risk with DHCA versus MHCA and mild HCA.

Conclusions:

• Moderate to mild hypothermia strategies demonstrated reduced operative mortality and postoperative stroke risk in the analyzed studies.
• These findings suggest that less profound cooling may be beneficial for aortic arch surgery outcomes.
• Large-scale prospective studies are recommended to further elucidate optimal temperature management for aortic arch pathologies.