Systemic temperature and paralysis after thoracoabdominal and descending aortic operations

Area of Science:

• Cardiovascular Surgery
• Neurology
• Critical Care Medicine

Background:

• Systemic temperature is a known factor influencing neurologic deficit development post-aortic surgery.
• Understanding the impact of different hypothermia levels is crucial for optimizing patient outcomes.

Purpose of the Study:

• To investigate the relationship between varying degrees of systemic hypothermia and the incidence of neurologic deficits following aortic surgery.
• To identify predictors of neurologic injury and mortality in patients undergoing complex aortic repairs.

Main Methods:

• Retrospective analysis of prospectively collected data from 132 patients undergoing complex aortic repairs.
• Patients were categorized by hypothermia: mild (36.5°C), moderate (29-32°C), or profound (<20°C).
• Outcomes assessed included permanent and transient neurologic deficits, and 30-day survival.

Main Results:

• Permanent deficits occurred in 3.8% of patients, with no significant difference across hypothermia groups (P=.70).
• Transient neurologic deficits were significantly lower in moderate (6.6%) and profound (6.5%) hypothermia groups compared to mild hypothermia (32%) (P=.004).
• Independent predictors of deficits included intercostal ischemic time, mild hypothermia, and absence of cerebrospinal fluid drainage. 30-day survival was 92.4%.

Conclusions:

• Moderate or profound hypothermia is associated with a reduced incidence of transient neurologic deficits after aortic surgery.
• Recommendations include active cooling and cerebrospinal fluid drainage for most patients, with profound hypothermia considered for complex repairs and reoperations.
• Surgical acuity was the only multivariable predictor of death.