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M. A. Mauro and S. E. Black
(VitaCuff; Vitaphore, Menlo Park, CA) that is placed at
the catheter exit site to serve as an antimicrobial barrier
(see Figs. 35-1 and 35-2).
Subcutaneous ports
All implantable devices have a port component buried in
the subcutaneous space connected to a catheter with its
tip placed in the central venous system (see Fig. 35-3).
The ports are available with single or dual chambers and
are constructed of stainless steel, titanium, or plastic
[magnetic resonance imaging (MRI) compatible]. The
traditional reservoir port is accessed by the use of a noncoring needle that enters the port via a compressed silicone disc. Subcutaneous ports are now available in a wide
range of sizes that can better accommodate the patient’s
size and amount of subcutaneous tissue (see Fig. 35-3).
Small ports are also available for extremity placement in
the forearm or upper arm.
9,16
■ Device Selection
The appropriate choice of a device depends on multiple
factors: frequency, length, and type of therapy and use
and personal preference (e.g., physician, nurse, home
health care personnel, patient). Frequent access (daily)
will favor the choice of an external catheter, whereas
infrequent use (weekly, monthly) favors a port. Ports are
significantly more expensive than external catheters, but
they require significantly less maintenance when not in
use. Therefore, when the devices are used infrequently,
ports become more cost efficient when in place approximately 6 months or longer. Because of the different diameters and thicknesses of the port septum in chest wall
(standard size) and extremity ports, the chest-wall ports
will accept twice as many needle punctures.
Multiple-lumen catheters have a higher infection rate
compared with single-lumen devices. Therefore, the device with the fewest lumens required should be selected.
A single-lumen device should be selected for single use or
nonsimultaneous multiple uses, whereas a multilumen
device will be needed for multiple simultaneous uses.
Often, the type of therapy will affect the device choice.
If blood drawing will be needed, devices larger than 3 or
4 Fr will be helpful. If a triple-lumen device is required, a
port or PICC is not a possibility. If high flow rates are
required (pheresis, hemodialysis) staggered tip external
catheters will be needed.
Finally, the personal preference of the physician may
be a factor but should not be the overriding consideration. A device must be selected that will accomplish the
treatment plan. Physician preference is the least important factor. The interventional radiologist should be able
to place all types of devices. It is much more important to
14,15
consider the opinions and experience of the health care
personnel that will be accessing and managing the device
over the long term as well as the feelings of the patient.
If a variety of options exist, they should be discussed with
the patient before the procedure.
■ Placement Techniques
Percutaneous placement of long-term central venous access devices requires three basic procedural steps: (a)
venous access, (b) formation of a subcutaneous tunnel or
pocket, and (c) placement of the catheter into the central venous circulation.
Venous access
Conventional access sites include the subclavian vein
(SCV), axillary vein, internal and external jugular veins,
and the cephalic and basilic veins of the upper extremity.
The choice of access site depends on the device to be
placed, venous patency, existing access, and patient preference. Nontunnelled and tunnelled catheters as well as
chest wall ports are routinely placed via SCV or axillary
7,15
access.
The internal jugular (IJV) vein is preferred for
the placement of dialysis catheters to avoid injury to the
SCV and complications following upper-extremity shunt
or fistula placement.
17
The right IJV also is preferred to
minimize catheter malposition when fluoroscopic guidance is unavailable because of its direct relationship to
the SVC and right atrium. PICC are routinely placed
through the antecubital veins or the basilic and cephalic
veins in the upper arm.
10
A routine ultrasound examination of the conventional
access sites is performed to determine venous patency.
When all conventional access sites are occluded, a variety
of unconventional sites are considered, including the
inferior vena cava (via translumbar or transhepatic approaches), hepatic vein, collateral channels, andoccluded
venous segments.
18
A patient with an existing catheter
usually will have a new site chosen for the device to minimize the risk of infection. In cases of difficult or limited
access sites, the existing site may be used. Indwelling tun-
4
nelled catheters also can be exchanged for new catheters
using conventional guidewire exchange techniques, particularly when the tunnel has matured.
Most patients prefer to have the device placed on the
nondominant side if possible. Previous surgery (e.g., mastectomy) or radiation therapy will dictate contralateral
access.
Subclavian/axillary vein
Access techniques tothe subclavianvein include(a) standard percutaneous insertion using bony landmarks, (b)
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fluoroscopic guidance with or without venography, and
(c) ultrasound guidance. The standard “blind” technique
describes advancing the entry needle along a horizontal
plane under the medial two thirds of the clavicle toward
the suprasternal notch. Entry into the SCV isquite medial.
Direct puncture of the axillary or SCV can be made
under direct fluoroscopic vision during contrast administration via an extremity vein or placement of a guidewire
via an antecubital or transfemoral approach (Fig. 35-4).
When contrast is being used, a preliminary injection is
performed to document patency and to select an appropriate skin site. Following preparation, a second contrast
injection is performed, and when the vein is opacified,
the needle is advanced at an oblique angle (45 degrees)
with a tightly collimated field. The vein will be indented
initially by the needle and then entered. Safe entry into
the SCV also can be accomplished by using the first rib as
a fluoroscopic marker.
20
A skin nick is made at the lateral
margin of the second rib, and the 21-gauge needle is
obliquely inserted to hit the anterior lateral first rib immediately caudal to the most lateral extent of that rib.
With the most lateral aspect of the first rib 90 degrees
from vertical, the SCV will cross the first rib between 85
and 104 degrees in 82% of patients.
20
This technique has
proved to be an alternative to contrast administration or
ultrasonography.
Ultrasound guidance using a 5- or 7.5-MHz linear
transducer is our preferred guidance method for venous
access (Fig. 35-5). Ultrasound guidance confirms venous
patency, allows a more peripheral entr y and reduces the
risk of pneumothorax and inadvertent arterial punc-
4,21
ture.
It is absolutely critical to enter the vein lateral to
the first rib–clavicle junction to prevent the “pinch-off”
syndrome.
22,23
When punctures are made more medial,
the catheter will traverse the costoclavicular ligament and
the tendon of the subclavius muscle. Subsequent arm
motion will compress the catheter and lead to fracture
and an intravascular foreign body. The SCV/axillary venous segment can be imaged in either the transverse or
longitudinal plane (see Fig. 35-5). Longitudinal imaging
allows constant identification of the needle tip, whereas
transverse imaging allows simultaneous imaging of the
vein and adjacent artery.
24
Venous entry should be lo-
cated between the lateral margins of the first and second
19
ribs. The needle is advanced until the vein is indented. A
short thrust is then necessary to puncture the wall. Blood
should be freely aspirated before guidewire insertion.
Contrast confirmation can be performed but is not necessary with ultrasound guidance. The course of the 0.018inch guidewire should be observed to ensure that it enters the right atrium and not the aorta and left ventricle
(indicating an inadvertent arterial puncture). Note that
pulsatile blood (signifying arterial entry) will not occur
when a 21-gauge needle enters an artery. The needle
should not be advanced farther beyond the vein (avoiding a pneumothorax) but partially withdrawn and redirected when venous entry is not successful. Following
placement of the mandril guidewire, a transition catheter
is placed into the venous system.
Internal jugular vein
IJV access can be accomplished by using standard or
ultrasonography-guided techniques. The most common
standard approach to the IJV consists of retracting the
carotid artery medially while the needle is inserted at a
point midway between the angle of the mandible and
clavicle directed toward the ipsilateral nipple. The IJV
and immediately adjacent carotid artery are easily imaged with ultrasonography. Displayed in the transverse
orientation, the IJV and carotid artery will be side by side,
or the vein will lie anterior to the arter y (Fig. 35-6). With
ultrasound guidance, a rather low site is selected between
the two heads of the sternocleidomastoid muscle. Ordinarily, this low approach increases the risk of a pneumothorax when standard techniques are used, but this is not
a concern with ultrasonography guidance.
cm) 21- or 18-gauge needle is used and directly inserted
into the IJC. A short, brisk thrust is needed to enter the
vein. The appropriate guidewire is then advanced to the
right atrium.
24
A short (4
FIGURE 35-4. Venogram of the axillary/subclavian venous
segment for venous access. Location where venous entry
should be made, lateral to the first rib/clavicle junction (
arrow
Extremity veins
Access for the radiological placement of PICC and extremity ports is most commonly by the cephalic or basilic
veins in the upper arm. These devices also can be placed
following access of the antecubital veins. Venous access
for the upper arm veins is accomplished by either fluoroscopic guidance during contrast administration or by ul-
).
trasound (Fig. 35-7). Entry usually is made halfway be-
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A B
FIGURE 35-5. Subclavian/axillary ultrasound for venous access. A: Longitudinal view of large axillary vein (V). B: Transverse
view of axillary artery (a) and vein (V). The vein is located just inferior to the artery in this location. Safe access requires image
guidance.
tween the elbow and axilla. When the fluoroscopic
method is used, an intravenous line is started in the
antecubital fossa or more distally in the arm.
25,26
should be performed to confirm a continuous path to the
heart. The contrast injection can be performed following
the placement of a small (3 Fr) dilator.
A
venogram is initially performed to identify an appropriate vein to enter. The vein should be of adequate size (at
least 3 to 4 mm in diameter) and should lead directly to
the central circulation. Following preparation of the upper arm, a contrast injection is repeated to select the
specific site of entry. A local anesthetic is placed and a
small dermatotome created. During another contrast injection, a 7-cm, 21-gauge needle is inserted into the vein
followed by the 0.018-inch guidewire. If venospasm is
present, intravenous nitroglycerin should be administered in small aliquots of 100 to 200 lg.
Veins in the upper extremity also can be imaged by
using ultrasound.
24
The veins are imaged in the transverse plane, and the needle is guided directly into the
vein. Following free return of blood, a contrast injection
Unconventional venous access
When conventional sites are occluded, successful catheter placement still can be accomplished by using unconventional sites. The IVC can be accessed via a translumbar
approach similar to translumbar aortography (Fig. 35-8).
If the common femoral veins are patent, a guidewire can
be easily placed into the IVC to serve as a fluoroscopic
marker. The chosen skin site is just superior to the iliac
crest to allow a 45-degree medial and slight cephalad
angulation. Oblique fluoroscopy is used to direct the
21-gauge diamond-tipped needle to the target. If a guidewire was not inserted, the needle is directed to the L-3
vertebral body. Once bony contact is made, the needle is
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with a 21- or 22-gauge needle and withdrawn during
aspiration. When blood is returned, contrast is injected
to confirm hepatic vein entry. Hepatic-vein access has
been most useful in children with short-gut syndrome in
whom all other sites have become occluded.
Collateral channels develop around chronic venous occlusions. These channels can be identified with either
ultrasonography or during venography and directly accessed. With the use of hydrophilic and steerable catheters and guidewires, these collateral channels may be able
to be catheterized with eventual central access. Exchangelength hydrophilic guidewires then can be used to insert
catheters into the central circulation. The newer polyurethane materials are preferable to silicone because they
have small outer diameters and they track over guidewires
more easily.
18,33
Catheterization of the dominant collateral can result in extremity edema if subsequent thrombosis occurs, but if it must be done, the patient should be
given a low dose of coumadin (1 mg/day) to help prevent
thrombosis.
FIGURE 35-6. Transverse ultrasound of the internal jugular
vein (V) and carotid artery (a). Access is easily accomplished
using transverse imaging.
withdrawn slightly and redirected anteriorly. The stylet is
removed, and aspiration is performed as the needle is
withdrawn until blood is returned. The 0.018-inch mandril guidewire then is inserted, followed by a transition
27–31
dilator.
If the infrarenal IVC is occluded, the suprarenal IVC
can be accessed either by a direct transhepatic approach
or through a hepatic vein.
32
We prefer to access the IVC
via a peripheral hepatic vein to maximize intravascular
catheter length and to facilitate subsequent manipulation. Hepatic vein access usually is accomplished by
either a subcostal or intercostal approach using ultrasound guidance. The middle hepatic vein is most suitable
for ultrasound targeting because of its anterior course.
The hepatic veins also can be accessed using fluoroscopic
guidance in which percutaneous transhepatic cholangiography (PTC)-like passes are made through the liver
■ Device Insertion (Table 35-2)
PICC
Immediately following access, an appropriately sized peelaway sheath is inserted. A more exact measurement can
be obtained by advancing the guidewire to the final location of the catheter tip and clamping the guidewire at the
hub of the dilator. An additional length often is added to
allow the catheter to be coiled so that the hub is directed
toward the axilla (for upper arm placement).
10–12, 26
Nontunnelled, centrally placed catheters:
Hohn catheter
The nontapered catheter often can be inserted into the
venous system directly over the 0.018-inch guidewire. In
obese patients, a transition dilator, followed by an 8 Fr
peel-away sheath, can be inserted, followed by the Hohn
catheter. The peel-away sheath is removed following
placement.
4,13
Tunnelled catheters (Figs. 35-9 and 35-10)
Following venous access, a transition dilator is placed into
the right atrium, and an intravascular guidewire measurement is made. The tip of the guidewire is placed at the
desired location of the catheter tip, and the guidewire
then is kinked at the hub. The guidewire is withdrawn
until the tip is at the venous access site, at which time a
hemostat is clamped to the guidewire. The distance from
the clamp and kink represents the length of catheter
required from the venous access site to final tip location.
448 M. A. Mauro and S. E. Black
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A B
FIGURE 35-7. Extremity vein access. A: Venogram of upper extremity demonstrating continuity of flow to the heart and
localizing site of venous entry (
within vein.
Typically, catheter tips are located in the distal SVC or
proximal right atrium.
The exit site in the skin for tunnelled catheters placed
through the SCV/axillary vein is typically adjacent to the
inferior aspect of the sternum. For IVC catheters, the exit
site is usually in the lateral aspect of the upper abdominal
or lower chest wall.
18,31
For end-hole catheters, a blunt tunnelling tool (supplied in a kit) is negotiated from the catheter exit site to
the venous access site. Then the catheter is connected to
the tail of the tunnelling tool and brought through the
tunnel. The Dacron cuff is situated approximately 1 to 2
cm from the exit site. The catheter is trimmed using the
intravascular guidewire measurement. For valved-tipped
catheters, the tunnel is created in the reverse direction:
from venous access site to skin exit site. Valved-tipped
catheters should not be cut at the tip but should instead
be trimmed from the hub end following placement of the
tip into the venous system and the proximal end through
the subcutaneous tunnel.
4,5,7,34
8
arrow
). B: Longitudinal ultrasound of basilic vein (
correct length, a 0.038-inch guidewire is inserted through
the transition dilator and exchanged for the appropriately sized peel-away sheath (supplied in a kit). The patient must be carefully instructed and reminded to suspend respirations during this period to avoid air
embolism. Alternatively, the patient can be instructed to
hum, or if the patient is unable to cooperate, the sheath
can be pinched between the fingers to help avoid air
embolism.
intermittently checked until its final location is satisfactory, at which time the sheath is removed.
SCV access) orthe contralateral brachiocephalic vein.
Rotation of the beveled catheter tip, deep inspirations,
placement of a long sheath or a forceful saline injection
will often correct the situation.
fail, a hydrophilic guidewiresteered into the SVC will solve
the problem. Kinking of the sheath will not allow passage
of the catheter and may occur at the site of venous entry
black arrows
) showing guide wire (
white arrows
After the end-hole catheter has been trimmed to the
35
The catheter is inserted and its position is
Occasionally, the catheter will enter the IJV (from an
36–38
4,36
When these maneuvers
)
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FIGURE 35-8. Translumbar Hickman catheter placement. Because of occlusion of all chest access sites, a Hickman catheter was placed into the central venous system via a translumbar approach.
transfemorally to mark the location of the IVC.
tip of catheter at right atrium (RA)
arrow:
course of catheter through retoperitoneum.
Large straight white arrow:
guidewire placed
Curved white
Small white arrows:
Black arrow:
skin
site for venous access. Patient is prone.
TABLE 35-2.
Device Insertion steps
Peripherally inserted Access vein
central catheter GW to RA, insert sheath
Nontunnelled chest wall Access vein
catheter GW to RA
Tunnelled chest-wall catheter Access vein
“Hickman type” Place temporary catheter
Subcutaneous port: chest Access vein
wall “pre-attached” Place temporary catheter
Extremity “attachable” Access vein
US, ultrasound; GW, Guidewire; RA, Right atrium.
Device Insertion
GW measurement, trim catheter
Insert catheter
Dilate
Insert catheter
GW measurement
Create tunnel
Bring catheter through tunnel
and trim length
Insert sheath
Insert catheter
GW measurement
Create pocket and tunnel
Bring catheter through tunnel and
seat port into pocket
Secure port to deep fascia
Access port and flush
Close incision
Trim catheter to length
Insert sheath
Insert catheter
Insert sheath
Insert catheter and flush
Create pocket and tunnel (if needed)
Bring catheter through tunnel and
trim to length
Attach catheter to port and flush
Seat port into pocket
Close incision
Subcutaneous ports
(e.g., in obese patients in whom a vertical-needle approach is used) or at the acute angle formed by the SCV
and right brachiocephalic vein. This can often be avoided
by a peripheral and oblique needle insertion. If kinking
occurs at the brachiocephalic vein, the sheath is withdrawn as forward pressure is maintained on the catheter.
The catheter will eventually pass when the sheath is withdrawn proximal to the acute junction. Kinking at the vein
must be overcome by external pressure applied to the soft
tissues in an effort to reduce the kink.
After venous placement is completed, the catheter is
secured with sutures (3-0 or 4-0) placed at the venous
access and catheter exit sites. The suture placed at the
catheter exit site is also wrapped around the catheter for
additional stability. The catheter then is heparinized, and
an external dressing is applied.
Chest wall ports (Figs. 35-11 and 35-12)
In addition to the standard materials for venous entry, a
surgical cut-down tray containing the appropriate scalpels, scissors, and other instruments will be needed. Formation of the subcutaneous pocket will follow the initial
venous access. A site on the upper chest wall inferior to
the clavicle with ample subcutaneous tissue is chosen.
The pocket should avoid breast tissue and the axilla.
Following local anesthesia of xylocaine with epinephrine,
a horizontal 5-cm skin incision is made with a no. 15
blade. Vertical incisions can be made but are not preferred. The pocket may be situated either superior or
inferior to the incision. The relationship of the pocket to
the incision is based on physician preference. The following discussion assumes that the incision has been placed
inferior to the pocket.
4,14,15
The pocket is formed using blunt dissection and
should be just large enough to accommodate the device
450 M. A. Mauro and S. E. Black
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A
B
D
C
E
FIGURE 35-10. Postinsertion radiograph of a Hickman cathe-
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ter.
Straight black arrow:
rior vena cava (SVC) junction.
site at parasternal border.
Curved white arrows:
site.
Catheter tip at right atrium (RA)/supe-
Curved black arrow:
Straight white arrow:
Catheter within subcutaneoustunnel.
Catheter exit
Venous access
without excessive tension on the apposed margins of the
incision. A pocket that is too large may allow port torsion
to occur. The port is placed into the pocket, checking
for size and position. If these are suitable, the pocket is
inspected visually to ensure that no bleeding is present.
At this time, a tunnel is created to connect the upper
outer portion of the subcutaneous pocket to the original
venous access site. If a preattached port (catheter and
port connected in the factory) was chosen, the catheter
is brought through the tunnel and the port positioned
into the pocket. The port then is sutured to the deep
fascia using 3-0 absorbable suture. At this time, the port
is accessed through the skin with a special noncoring
Central Venous Access 451
needle connected to tubing. The port and catheter are
flushed with normal saline. The pocket is closed in a
two-layer fashion using deep interrupted, inverted subcuticular stitches with 3-0 or 4-0 absorbable sutures and
interrupted skin sutures using 3-0 or 4-0 monofilament
nonabsorbable suture. This wound closure method is the
technique used at the University of North Carolina. Another popular closure technique is a running subcuticular stitch with absorbable suture and Steristrips (3M
Health Corp., St. Paul, MN) applied at the skin level.
Following closure of the subcutaneous pocket, the
catheter is cut to a length based on the intravascular
guidewire measurement obtained during placement of
the transition dilator. The appropriately sized peel-away
sheath is placed. While the patient suspends respirations
(having the patient hum is also useful), the guidewire
and dilator are removed and the catheter is placed
through the peel-away sheath into the proper location
confirmed by fluoroscopy. The peel-away sheath is removed. Blood is aspirated from the port through the
indwelling needle and flushed first with saline and then
with heparin (according to manufacturer’s recommendations). A single nonabsorbable suture is placed in the
original venous access dermatotom. Then all incisions
are dressed.
When a valved type catheter or a detached end-hole
catheter has been chosen, the subcutaneous pocket is
placed inferior to the incision. After the pocket is created, the catheter is placed into the venous system via its
peel-away sheath and is properly positioned. The peelaway sheath is removed, and a tunnel is created from the
venous access dermatotom to the incision. The back end
of the catheter is brought through the tunnel, trimmed
to the correct length, and connected to the port. Blood
is aspirated from the port and flushed with saline. The
port is placed in the pocket and secured to the deep
fascia. All incisions are closed. The port is finally accessed
through the skin with a noncoring needle to confirm a
functioning port. Then the port is heparinized.
Extremity ports
Following venous access into the basilic or cephalic veins,
a peel-away sheath is placed in the venous system. The
pocket is created by making a transverse incision, which
may include the initial access site. Alternatively, the in-
FIGURE 35-9. Hickman catheter insertion. A: Following venous entry, a transition dilator is placed into the subclavian axillary vein
(SVC). Note entry lateral to first rib/clavicle junction. B: The subcutaneous tunnel then is created by using a blunt tunneling tool
passed within the subcutaneous space from the catheter exit site (adjacent to the lower aspect of the sternum) to the venous
access skin site. C: The catheter is attached to the rear of the tunneling tool and dragged through the tunnel such that the Dacron
cuff lies 1 to 2 cm from the catheter exit site. The catheter tip then is trimmed to length based on the intravascular guidewire
measurement obtained earlier in the procedure. D: The transition dilator is exchanged over a guidewire for the peel-away sheath.
While the patient suspends respirations, the inner dilator and guidewire are removed and the Hickman catheter is placed through
the sheath to its final location. The peel-away sheath is removed, the catheter is flushed and heparinized, incisions are closed, and
the catheter is dressed. E: The peel-away sheath is removed while maintaining portion of indwelling catheter.
A
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B
C
E
D
F
FIGURE 35-12. Postinsertion radiography of a subcutaneous
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port:
Large straight arrow:
subclavian axillary vein (SVC) junction.
access site.
cutaneous tunnel connecting pocket to the venous access site.
Small straight arrows:
Tip of catheter at right atrium (RA)/
Curved arrow:
portion of catheter in sub-
venous
cision for the pocket can be placed distal to the venous
access site, in which case a short tunnel connecting the
two sites will be required. Once an adequate pocket is
made, the catheter is inserted into the venous system
through the peel-away sheath and placed at the
SVC/right atrium (RA) junction confirmed by fluoroscopy. The sheath is removed, and the back end of the
catheter is brought through the tunnel (if needed) to
exit at the incision. The catheter is trimmed and connected to the port, which then is flushed with saline.
The port then is placed in the pocket and secured with
absorbable sutures. The incision is closed by using either
interrupted subcuticular plus skin suture or a running
subcuticular stitch with Steri-strips at the skin. The port
is finally accessed through the skin and hepar-
16,39–41
inized.
Central Venous Access 453
Dialysis catheters (Fig. 35-13)
Most dialysis catheters are dual-lumen, staggered-tipped
catheters that are capable of high (⬎ 250 mL/min) flow
rates. They are available in cuffed (long-term catheters
requiring a subcutaneous tunnel) or noncuffed (temporary, short-term catheters without a tunnel) designs.
Dialysis catheters are placed via the large central veins
because of their relatively large size. The IJV is preferred,
but the risk of subclavian vein stenosis is avoided because
it may complicate upper-extremity shunt placement.
Noncuffed tapered dialysis catheters are designed for
short-term use and are placed using standard Seldinger
techniques.
4
The cuffed dialysis catheters have a nontapered tip and are available in a number of fixed
lengths. These catheters cannot be trimmed. Following
venous access, an intravascular guidewire measurement
is made from the projected position of the distal tip
(usually in the proximal RA) to the venous access site.
Using this measurement, the appropriate catheter is chosen so that the cuff will lie in the proximal portion of
the tunnel. The tunnel may be created in a supraclavicular or infraclavicular location. The tunnel is created from
the catheter exit site to the venous access site, and the
catheter is brought through it. The large peel-away
sheath is placed in the vein and the catheter is placed
in the venous system after the guidewire and dilator is
removed while the patient suspends respirations,
4,42
which is critically important, because if the patient inspires while the large sheath is not occluded, an air embolism will occur. The peel-away sheath is removed, and
each lumen is heparinized according to manufacturer’s
recommendations, which vary with the length of the
catheter.
An alternative to the standard dual-lumen catheter is
two single-lumen catheters. The Tesio twin-catheter system entails two 10 Fr catheters, each with a large end hole
and multiple side holes that are placed via adjacent internal jugular vein punctures. The two catheters serve as the
“venous” and “arterial” lumen, respectively. The venous
catheter is positioned 2 to 4 cm distal to the arterial
catheter.
43–45
Following placement, twin parallel tunnels
are created from the access site to the catheter exit site,
which is commonly positioned adjacent to the sternum
inferior to the clavicle. The back ends of these catheters
can be trimmed because of their removable hubs.
FIGURE 35-11. Subcutaneous port insertion: A: Following venous access and the placement of a temporary catheter into the
superior vena cava (SVC) a horizontal incision is made with a no. 15 blade and the subcutaneous pocket is created with blunt
dissection. In this diagram, a preattached port will be placed which allows the pocket to be created superior to the incision. B:
Following the creation of an adequately sized pocket, a tunnel is made from the upper outer aspect of the pocket to the venous
access site. C: The tip of the catheter is attached to the tunneling tool and brought through the tunnel, and the port is placed into
the pocket. Two sutures usually are placed, fixating the port to the deep fascia, and the catheter is cut to length. D: The port is
accessed with a special noncoring needle and flushed with heparinized saline. The incision then is closed. E: The temporary
catheter is exchanged over a guide for the peel-away sheath, and the catheter is inserted into the venous system as the patient
suspends respirations. F: The peel-away sheath is removed, and the port is flushed and heparinized.
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