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132 Section II: Intracranial Procedures

The skin and subcutaneous tissue are incised at the site of the
abdominal incision. Any bleeding is controlled with bipolar cau-
tery. To verify that the peritoneum cavity and not just the subcuta-
neous tissue or abdominal wall has been penetrated, a blunt forceps
is passed well into the abdominal cavity. A pursestring suture is
placed around the abdominal wall incision using a monofilament
nonabsorbable suture material.
A subcutaneous tunnel is created connecting the two incisions
using Doyen intestinal forceps. Alternatively, a shunt passer (e.g.,
Shunt Passer; Codman & Shurtleff, Raynham, MA) is helpful in
creating this tunnel and pulling the shunt tubing from the cranial
incision to the abdominal incision. The shunt passer consists of a
long malleable tube containing a leader that attaches to the end of
the shunt to pull the shunt through the tube. The tip of the shunt
passer is inserted through the cranial incision and tunneled cau-
dally through the subcutaneous tissues to the abdominal incision.
Figure 14.3 Patient positioning. The skin is clipped from the skull along the Care must be taken during subcutaneous tunneling to avoid entering
entire subcutaneous pathway to the site of abdominal incision. The patient
is positioned so there is a flat plane between the cranial and abdominal inci-
sion sites with a rolled towel under the neck.

Figure 14.5 Cranial burr‐holes. The temporalis fascia is incised and a por-
tion of the temporalis muscle is reflected from the skull and retracted. A
Figure 14.4 Draping of the patient. The cranial incision site (A), the path of burr‐hole slightly larger than the ventricular catheter and any anchoring clip
the shunt, and the abdominal incision site (B) are draped and covered with is created using an air drill. A second, smaller burr‐hole is created to accom-
a transparent adhesive sheet. modate suture to secure the ventricular catheter to the skull.

Figure 14.6 Creating a subcutaneous tunnel. Large forceps are passed sub- Figure 14.7 Use of a shunt passer. A malleable shunt passer is used to create
cutaneously along the pathway of the shunt from the cranial incision to the the subcutaneous tunnel from the cranial incision site to the abdominal
abdominal incision. incision site. The tip of the shunt passer is visible exiting the abdominal inci-
sion site (arrow).