Background: We recently described a technique for monitoring intraspinal pressure (ISP) after traumatic spinal cord injury (TSCI). This is analogous to intracranial pressure monitoring after brain injury. We showed that, after severe TSCI, ISP at the injury site is elevated as the swollen cord is compressed against the dura.
Methods: In a patient with complete thoracic TSCI, we sequentially monitored subdural ISP above the injury, at the injury site, and below the injury intraoperatively. Postoperatively, we simultaneously monitored subdural ISP and intraparenchymal ISP at the injury site and compared the two ISP signals as well as their Fast Fourier Transform spectra.
Results: Subdural ISP recorded from the injury site was higher than subdural ISP recorded from above or below the injury site by more than 10 mmHg. The subdural and intraparenchymal ISP signals recorded from the injury site had comparable amplitudes and Fast Fourier Transform spectra. Intraparenchymal pulse pressure was twofold larger than subdural pulse pressure.
Conclusion: After severe TSCI, three intradural compartments form (space above injury, injury site, space below injury) with different ISPs. At the level of maximum spinal cord swelling (injury site), subdural ISP is comparable to intraparenchymal ISP.
Keywords: Intensive care; Intraspinal pressure; Neuromonitoring; Spinal cord injury; Spinal cord perfusion pressure.