Use of an epidural cooling catheter with a closed countercurrent lumen to protect against ischemic spinal cord injury in pigs

J Thorac Cardiovasc Surg. 2007 Nov;134(5):1220-6. doi: 10.1016/j.jtcvs.2007.06.015.


Objective: We developed an epidural cooling catheter containing cold saline solution circulating in an isolated lumen. After placement by a minimally invasive approach, we evaluated protection effect against ischemic spinal cord injury in pigs.

Methods: Fourteen pigs underwent thoracic aortic double clamping for 45 minutes under systemic mild hypothermia (36 degrees C). Group A (n = 7) underwent local hypothermia with the cooling catheter. Group B (n = 7) underwent catheter placement only, without cooling. Spinal cord somatosensory evoked potentials were recorded to assess electrophysiologic status. Neurologic function was evaluated with a modified Tarlov score.

Results: At aortic crossclamping, spinal temperature in group A (26.5 degrees C +/- 2.4 degrees C) was significantly lower than that in group B (35.3 degrees C +/- 0.6 degrees C, P = .0001). Mean time from aortic crossclamping to onset of potential loss was significantly longer in group A (28.4 +/- 6.6 minutes) than in group B (18.3 +/- 5.0 minutes, P = .007). Mean duration of total loss of potentials was significantly shorter in group A (19.0 +/- 6.7 minutes) than that in group B (31.3 +/- 5.9 minutes, P = .003). Group A showed significantly better neurologic function (mean Tarlov score 4.4 +/- 0.8) than that of group B (0.1 +/- 0.4, P = .0001). Mean total number of intact motor neurons was significantly greater in group A (24.5 +/- 6.8) than that of group B (9.9 +/- 6.8, P = .0001).

Conclusion: By cooling the spinal cord selectively and continuously, the newly designed epidural cooling catheter prevented ischemic injury in a pig model of aortic crossclamping.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aorta, Thoracic / surgery
  • Body Temperature
  • Catheterization*
  • Constriction
  • Disease Models, Animal
  • Epidural Space
  • Evoked Potentials, Somatosensory
  • Hypothermia, Induced / instrumentation*
  • Sodium Chloride / therapeutic use
  • Spinal Cord Injuries / etiology
  • Spinal Cord Injuries / prevention & control*
  • Spinal Cord Ischemia / etiology
  • Swine
  • Vascular Surgical Procedures / adverse effects


  • Sodium Chloride