Introduction: Leakage of cerebrospinal fluid (CSF) can lead to fistula formation, pseudomeningocoele, neurological injury, infection and death. CSF leaks increase operative time and hospital stays. We tested a new fibrin dressing (NFD) that does not contain a collagen or cellulose backing in a CSF leak model. The carrier for the dressing is a mat of dextran nanofibers that dissolves immediately on contact with blood, leaving behind only a fibrin clot.

Methods: The cranium of 6 adult sheep was exposed and four craniotomy sites were created connecting 2 14mm burr holes. A 12-14mm durotomy was created and CSF leak was confirmed. After closure with a running 5-0 silk suture a Valsalva maneuver was performed (20cm water for 15 seconds). If the durotomy leaked CSF the NFD was applied for 3 minutes. After 5 more minutes a Valsalva maneuver was performed again and observed with loupe magnification by 3 investigators. If CSF leak continued, a second dressing was applied in the same manner.

Results: Suture alone controlled CSF leak in 3 of 23 (13%) durotomies (95%CI (2.78,33.6%)). The NFD controlled CSF leak in all 20 (100%) remaining durotomies (95% CI (83.2%, 100%)), demonstrating that suture+NFD is superior to suture alone (p<0.0001). Three injuries required 2 dressing applications. NFD stopped CSF leak even in presence of dura torn by suture and cerebral herniation.

Conclusions: The NFD was a useful adjunct to suture repair in this durotomy model. The NFD was able to control CSF leak even when the dura could not be approximated with suture. A parallel study of lumbar durotomies in a caprine model treated with the NFD showed no pseudomeningocoele or histologic evidence of abnormal inflammation or fibrosis after 30 days of survival indicating the safety of the dressing.

Patient Care: We believe that this NFD will significantly reduce morbidity, mortality, surgical time, hospital stay and overall costs of persistent CSF leak from purposeful and incidental durotomies in cranial and spinal surgery.

Learning Objectives: Surgeons should be able to describe the importance of the NFD in controlling CSF leak.

References: Floyd CT et al. Salmon thrombin-fibrinogen dressing allows greater survival and preserves distal blood flow compared to standard kaolin gauze in coagulopathic swine with a standardized femoral artery injury. 2012. J Spec Ops Medicine, 12(2):16-26.