Regional adenosine attenuates postischemic spinal cord injury

Area of Science:

• Cardiovascular Surgery
• Neuroprotection
• Experimental Medicine

Background:

• Thoracic and thoracoabdominal aortic surgeries carry a high risk of postoperative paraplegia (20-30%).
• Current strategies to mitigate paraplegia include hypothermia, barbiturates, and shunts.
• Spinal cord protection strategies aim to reduce energy demands or improve blood flow.

Purpose of the Study:

• To investigate the hypothesis that spinal cord perfusion with hypothermic solutions or adenosine can prevent or reduce paraplegia.
• To evaluate the efficacy of regional hypothermia and adenosine in preventing ischemic spinal cord injury.

Main Methods:

• New Zealand white rabbits underwent 40 minutes of infrarenal aortic isolation.
• Control group: aortic occlusion without protection.
• Experimental groups: aortic cross-clamping with regional hypothermia perfusion (Group I), systemic adenosine (Group II), or regional high-dose adenosine perfusion (Group III).

Main Results:

• Neurologic function was assessed using the Tarlov scale.
• Nonparaplegic animals in Group I (regional hypothermia) had a mean Tarlov score of 1.5.
• Nonparaplegic animals in Group III (regional adenosine) showed a significantly higher mean Tarlov score of 3.4.
• Histologic examination revealed no significant differences in spinal cord tissue between groups.

Conclusions:

• Regional adenosine administration effectively attenuates ischemic injury following aortic occlusion in this rabbit model.
• These findings support the potential of regional adenosine perfusion as a neuroprotective strategy against paraplegia.
• Further research may explore optimizing adenosine delivery for clinical application.