Profound Hypotension before Aortic Clamping Can Exacerbate Spinal Cord Ischemic Injury after Aortic Surgery in Rats

Area of Science:

• Cardiovascular Surgery
• Neurology
• Pathophysiology

Background:

• Spinal cord ischemia is a severe complication following aortic repair in acute aortic syndrome.
• The impact of pre-aortic clamping hypotension on spinal cord injury remains unclear.

Purpose of the Study:

• To investigate the effect of varying degrees of hypotension before aortic clamping on spinal cord injury.
• To evaluate neurological function, histopathology, oxidative stress, and inflammation.

Main Methods:

• 48 male Sprague-Dawley rats were divided into sham, control, mild hypotension, and profound hypotension groups.
• Spinal cord ischemia was induced via aortic catheterization.
• Neurological function (Motor Deficit Index), spinal cord histology, oxidative stress (malondialdehyde), and inflammation (TNF-α) were assessed.

Main Results:

• Profound hypotension significantly increased Motor Deficit Index 48 hours post-reperfusion.
• The profound hypotension group showed a lower number of normal motor neurons.
• Increased levels of malondialdehyde and TNF-α were observed in the profound hypotension group.

Conclusions:

• Profound hypotension before aortic clamping aggravates neurological outcomes after aortic surgery.
• This is mediated by increased neurological injury, reduced motor neuron count, oxidative stress, and inflammation.