Townsend Courtney M.Jr., Evers B. Mark. Atlas of General Surgical Techniques: Expert Consult

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CHAPTER 92 • Insertion of Peritoneal Venous Shunts 1021

Proposed incisions

Elastic

vessel loop

Phrenic nerve

Vagus nerve

Prolene suture

Clavicular head of

sternocleidomastoid muscle

Omohyoid muscle

Sternal head of

sternocleidomastoid

muscle

Clavicle

FIGURE 92 –2

1022 Section XII • Vascular

2. DISSECTION

◆ The skin, subcutaneous fat, and platysma muscle are incised. The sternal and clavicular

heads of the sternocleidomastoid muscle are split. The jugular vein is located lateral to the

carotid artery and can be used as a landmark to facilitate the identiﬁ cation of the vein. The

sheath that enwraps the vein keeps the vein from collapsing. This facilitates the circumfer-

ential dissection of the vein. If the dissection is close to the vein, damage to adjacent struc-

tures is minimal. The vein may have small tributaries coming into it, and disruption of

these may cause a moderate amount of bleeding. Identiﬁ cation and ligation with division

of these small vessels is advised. Elastic vessel loops are used proximally and distally to

allow occlusion of the blood ﬂ ow and control of the vessel in the operative ﬁ eld (see

Figure 92-2, B).

◆ After the skin incision is made, the subcutaneous fat is incised to the muscle. A 0.5% to 1%

solution of lidocaine is injected into the subcutaneous tract from the abdominal incision to

the jugular incision. The tract should run laterally on the chest wall, outside the area of the

breast and over the clavicle. Marking the route of the tract on the skin will help you stay on

course when passing the catheter/shunt. Push a vascular tunneling device through the sub-

cutaneous tissues deep to the skin but above the muscle fascia, following the tract that was

injected with the anesthetic. Pull the shunt from the bottom up, taking care to orient the

shunt correctly. Denver shunts have a one-way pump that should ﬁ t over the ribs. The

LeVeen shunts have a multiperforated abdominal end and a venous end that can be cut to

appropriate length (Figure 92-3).

CHAPTER 92 • Insertion of Peritoneal Venous Shunts 1023

Shunt tubing in

subcutaneous

tunnel

FIGURE 92 –3

1024 Section XII • Vascular

◆ The muscle in the abdomen should be split to expose the peritoneum. A purse-string with a

radius of 1 cm should be made in the peritoneum. Permanent suture is advised. Incision of

the peritoneum within the purse-string is made with electrocautery or scissors. While the

ascites is draining, place the intra-abdominal end of the shunt into the opening and thread

the tubing into the peritoneal cavity. Secure the purse-string around the shunt. If using the

LeVeen shunt, thread the entire catheter in until the disc is ﬂ ush with the peritoneum. Con-

nect the tubing running toward the neck incision to the port on the side of the abdominal

disc. Secure the tube to the disc with a large tie. If using the Denver shunt, thread the cath-

eter in until the “valve/pump” can be positioned over ribs 9 to 11. The subcutaneous tissue

will have to be dissected to create a cavity to support the pump. The pump should be

secured to the underlying tissue to avoid migration (Figure 92-4, A).

◆ Prime the tubing by aspirating at the venous end until there are no bubbles in the tubing. If

using the Denver shunt, press the pump several times until the ﬂ uid comes out the end of

the shunt. Clamp the tubing at the site where it enters the neck incision from below. Esti-

mate the length of the venous end of the shunt by placing the tubing onto the sternum. Cut

the tube at the point where it crosses the manubrium. Do not cut the tube at an angle,

because the tube may push against the side wall of the vein and obstruct the ﬂ uid ﬂ ow

(Figure 92-4, B).

CHAPTER 92 • Insertion of Peritoneal Venous Shunts 1025

Shunt tubing in

subcutaneous

tunnel

Site of transection

of catheter

Shunt valve

Peritoneal

catheter

FIGURE 92 –4

1026 Section XII • Vascular

◆ Place a purse-string suture in the anterior wall of the jugular vein with Prolene suture

(3-0 or 4-0). Occlude the vein with the elastic loops. Incise the vein within the purse-string.

Raise the head of the patient to approximately 35 degrees. Keep the tubing clamped at skin

level and tubing distal to the clamp ﬁ lled with the ascitic ﬂ uid or heparinized saline (2500

U heparin in 250 mL normal saline).

◆ Hold the edge of the incised vein and insert the tubing. Take tension off the lower elastic

loop to allow the tube to be advanced into the thorax. Secure the purse-string around the

tubing (Figure 92-5).

FIGURE 92 –5

CHAPTER 92 • Insertion of Peritoneal Venous Shunts 1027

3. CLOSURE

◆ The course of the shunt should be from the peritoneal cavity, exiting out the abdomen and

coursing along the lateral chest wall, across the clavicle to enter into the internal jugular

vein, ending at the junction of the superior vena cava and right atrium. All wounds should

be closed in two layers over the foreign body (the shunt) (Figure 92-6).

Peritoneal

catheter

Venous catheter

Denver

shunt valve

FIGURE 92 –6

1028 Section XII • Vascular

STEP 4: POSTOPERATIVE CARE

◆ The patient should be admitted for an overnight stay. The potential problems are fever, ﬂ uid

overload, and disseminated intravascular coagulation (DIC). Fever is usually transient and

treated symptomatically. The identiﬁ cation of infection occurs in approximately 5% of those

patients with fever and warrants treatment. Pulmonary edema occurs in approximately 10%

of the patients but usually can be handled with diuretics. DIC is usually subclinical and can

be treated expectantly. The worst case scenario is fulminant bleeding, which requires re-

moval of the shunt. The bleeding may be related to exposure of the systemic circulation to

ﬁ brin split products (FSP)–rich ascitic ﬂ uid that may activate the coagulation mechanism.

Bleeding complications do not appear to be related to the severity of the post-shunt coagu-

lopathy but rather to the severity of liver dysfunction and presence of preoperative DIC,

probably caused by the liver disease.

STEP 5: PEARLS AND PITFALLS

◆ The contraindications for shunt insertion should include pseudomyxoma peritonei, recent

or current infection, preoperative coagulopathy, liver failure, and loculated ascites. Relative

contraindications include positive cytologic ﬁ ndings in ascitic ﬂ uid and concurrent cardiac

failure. Bloody ascites and ascitic ﬂ uid protein content greater than 4.5 g/L are also consid-

ered contraindications to shunting, secondary to increased risk of shunt blockage from clot

or ﬁ brin plugs.

◆ If a patient has had episodes of variceal bleeding, the risk of rebleeding postshunt is great

secondary to the risk of postshunt coagulopathy and increased intravascular volume.

SELECTED REFERENCES

1. Smith EM, Jayson GC: The current and future management of malignant ascites. Clin Oncol

(R Coll Radiol) 2003;15:59-72.

2. Becker G, Galandi D, Blum HE: Malignant ascites: Systematic review and guideline for treatment.

Eur J Cancer 2006;42:589-597.

3. Suzuki H, Stanley AJ: Current management and novel therapeutic strategies for refractory ascites and

hepatorenal syndrome. QJM 2001;94:293-300.

1030

STEP 1: SURGICAL ANATOMY

◆ Cross-sectional anatomy of the lower leg is shown in Figure 93-1, A.

STEP 2: PREOPERATIVE CONSIDERATIONS

◆ Selection of level for amputation depends on the underlying pathology and the need to

ascertain efﬁ cient wound healing of the amputation stump.

◆ Below-knee amputation stumps do not rely on a symmetrical ﬂ ap closure, but rather the

posterior ﬂ ap with extensive musculature is to be brought anteriorly.

◆ Use of a tourniquet is at the discretion of the surgeon.

STEP 3: OPERATIVE STEPS

1. INCISION

◆ Planning the level of incision begins by determining the bony structures to preserve,

typically 2 to 3 ﬁ ngerbreadths below the tibial tuberosity (Figure 93-1, B).

◆ From this landmark, skin ﬂ aps are developed, typically the midpoint of the leg in an

anterior to posterior plane is identiﬁ ed, just below this level.

◆ The anterior ﬂ ap is incised anteriorly.

◆ The posterior ﬂ ap is incised as a semicircle, at its apex with a length equal to the distance

to reach the anterior margin of the wound.

CHAPTER

Below-Knee Amputation

Arthur P. Sanford

CHAPTER 93 • Below-Knee Amputation 1031

Tibialis anterior muscle

Extensor hallucis

longus muscle

Extensor digitorum

longus muscle

Peroneus longus muscle

Peroneus brevis muscle

Gastrocnemius muscle

(medial head)

Gastrocnemius muscle

(lateral head)

Tibia

Tibialis posterior muscle

Popliteus muscle

Great saphenous vein

Saphenous nerve

Soleus muscle

(tibial head)

Flexor digitorum

longus muscle

Soleus muscle

(fibular head)

Lateral sural

cutaneous nerve

Flexor hallucis

longus muscle

Sural nerve

Small saphenous vein

Peroneal artery and vein

Medial sural cutaneous nerve

Posterior tibial artery, vein, and nerve

Fibula

Division of anterior

and posterior skin flaps

and deep tissue

Level of bone division

Popliteal artery

Anterior tibial artery

Posterior tibial artery

Peroneal artery

FIGURE 93 –1