Abstract
Aim
Epidural blood patch has been used to treat spinal headache with varying success.
An experimental model was designed to ascertain whether an epidural blood patch can
be used to seal the needle puncture sites in dural repair.
Materials and Methods
Bovine dura was secured to the lower end of an open-ended calibrated plastic cylinder.
Multiple interrupted stitches were applied over a 02 cm length of the dura without
any incision. The cylinder was filled with colored saline gradually with the dura
placed in a dependent position. Height of the water column at which sutured dura leaked
was recorded. A layer of fresh blood was laid over the dura and allowed to clot. The
test was repeated and the hydrostatic pressure at which leak took place was noted
again. The test was repeated three times. Similar studies were done with two specimens
with 02-cm dural incisions repaired with interrupted stitches of 4-0 silk in one specimen
and 4-0 prolene in another, and three specimens with 3-mm unsutured dural rent in
one and dural punctures made with 23-G and 26-G spinal needles in the other two.
Results
All the dural preparations leaked, at a very low hydrostatic pressure (<30 mm of H2O). By covering the needle puncture sites with clotted blood, a watertight closure
could be achieved, that can withstand a much higher hydrostatic pressure (mean of
180 mm of H2O).
Conclusion
The experimental findings indicate that an epidural blood patch does enhance the ability
of a dural closure to prevent a leak; however, its utility in clinical setting is
questionable.
Key words
Epidural blood patch - experimental model - water-tight dural closure
