Venous Cutdown

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Chapter 23

Venous Cutdown

Management of critically ill or injured patients requires immediate and adequate vascular access, especially during trauma resuscitation, when rapid infusion of crystalloid or blood products may be necessary. Venous cutdown, a time-honored surgical technique, has largely been replaced by alternative methods of obtaining venous access, including intraosseous lines, the Seldinger technique, and ultrasound-guided central venous cannulation.1 Nonetheless, venous cutdown still has a role as an emergency method of achieving vascular access when other techniques and equipment are unavailable, particularly in settings outside the United States.

First described by Keeley in 1940 and Kirkham in 1945,2,3 venous cutdown offered an alternative to venipuncture in patients with shock. Though no longer taught as a mandatory procedure in the Advanced Trauma Life Support course, venous cutdown is considered optional and continues to be taught at the discretion of the instructor.4 Realistically, percutaneous vascular access may be infeasible in a pulseless, hypovolemic, or anatomically scarred patient. With a thorough understanding of the anatomy, the procedure, and its potential complications, this mechanically simple procedure can be performed quickly and effectively.5

Indications

Venous cutdown may be used as an alternative to venipuncture for critical patients in need of vascular access when less invasive options have been exhausted or are not available. Patients with severe shock, asystole, or pulseless electrical activity will lack palpable femoral pulses, thus making percutaneous femoral vein catheterization more difficult. Surface landmarks may be obscured and veins may be unusable in intravenous (IV) drug users, the extensively injured, or severely burned patients. Attempts at percutaneous venous cannulation may be complicated or even impossible in such patients. Venous cutdown and interosseous routes (see Chapter 25) are both viable options in such scenarios.

Hypovolemic Shock

Initially popularized during the Vietnam War for rapid transfusion, venous cutdown has since been used for resuscitation of patients with profound hypovolemia.8,9 The flow rate of saline through a standard IV extension set cut to a length of 28 cm (12 inches) and inserted directly into the vein is 15% to 30% greater than through a 5-cm, 14-gauge catheter. This difference is larger if pressure is applied to the system. Moreover, the improvement in flow rate through large-bore lines is greater for blood than for crystalloid solutions because the viscous characteristics of blood impede its passage through small-bore tubing.9 A unit of blood can be transfused in as little as 3 minutes through IV extension tubing inserted directly into the vein. Consequently, large-bore lines placed by venous cutdown are an excellent mechanism for the treatment of severe hypovolemia.

Contraindications

Venous cutdown is contraindicated when less invasive alternatives exist and when performing the procedure would cause excessive delay.10 Highly skilled clinicians may perform a cutdown in less than 60 seconds.11 However, multiple studies by Westfall,12 Rhee,13 Iserson,14 and their colleagues have indicated that on average, the procedure takes at least 5 to 6 minutes to complete. Use of the modified Seldinger technique described both by Shockley and Butzier and by Klofas has been shown to decrease that time by 22%.15,16 In general, the use of percutaneously inserted central venous catheters in either the subclavian, internal jugular, or femoral vein is preferable to a cutdown.

Absolute contraindications include major blunt or penetrating trauma involving the extremity on which the procedure is to be performed.17 Relative contraindications include vascular injury proximal to the cutdown site, overlying soft tissue infection, coagulopathies, compromised host defense mechanisms, and impaired wound healing. Other considerations include any previous saphenous vein harvest for coronary artery bypass or other vascular surgery proximal to the anticipated cutdown site.18 The indications for venous cutdown should be weighed against the potential complications.

Anatomy and Selection of the Site

Knowledge of the relevant anatomy is imperative for success. Veins in both the upper and lower extremities may be used. The size and accessibility of the target vessel along with the clinician’s experience and training are the principal factors in selection of the site. There are four primary locations at which venous cutdown is performed: the great saphenous vein distally at the ankle and proximally at the thigh, the basilic vein above the elbow, and the cephalic vein below it. Brachial vein cutdown is no longer recommended as an emergency venous access route because of its time-consuming dissection and risk for neurovascular injury. The anatomy of individual vessels and their relative merits as cutdown sites are described in the following sections.

The Great Saphenous Vein

The great saphenous vein is the longest vein in the body, and it runs subcutaneously throughout much of its course (Fig. 23-1). It is most easily accessible at the ankle but may also be cannulated below the knee and below the femoral triangle. The great saphenous vein begins just anterior to the medial malleolus, where it is a continuation of the medial marginal vein of the foot. The vein crosses 1 cm anterior to the medial malleolus and, together with the saphenous nerve, ascends along the anteromedial aspect of the leg.19,20 The saphenous nerve at this level is of relatively little clinical significance in that, if transected, it causes sensory loss in only a small area along the medial aspect of the foot. At the ankle, the vessel can be exposed with minimal blunt dissection. The vein’s superficial, predictable, and isolated location has made the distal saphenous vein the traditional pediatric cutdown site.19

At the knee, the saphenous vein lies superficially and medially. A cutdown performed 1 to 4 cm below the knee and immediately posterior to the tibia has been described in the pediatric literature.6 This site is seldom used, however, because of its many disadvantages, including kinking of the line as the knee is flexed and risk for injury to the saphenous branch of the genicular artery and the saphenous nerve.21 Of note, the great saphenous vein is duplicated in the calf in 25% of the population and may be present on exploration.22

In the thigh, the saphenous vein begins on the medial aspect of the knee and crosses anterolaterally as it ascends toward the femoral triangle. Approximately 4 cm below the inguinal ligament and 3 cm lateral to the pubic tubercle, the saphenous vein dips through the fossa ovalis, where it penetrates the femoral sheath and joins the femoral vein. The saphenous vein is easily isolated from the surrounding fat at this site because of its large caliber (4 to 5 mm in outside diameter) and superficial relationship to the femoral sheath (Fig. 23-2). Also lying anteromedially in the thigh is the lateral femoral cutaneous vein, which has a smaller diameter and lies lateral to the great saphenous vein.20 The saphenous vein at the thigh is a preferred site for cutdown given its large diameter and ease of accessibility. An 8.5-Fr catheter is easily introduced at this level and is ideal for rapid infusion of crystalloid or blood during resuscitation.17

The Basilic Vein

The basilic vein is a preferred site for venous cutdown in the upper extremity because of its predictable anatomic location. The size of this vein enables it to be located easily, even in hypotensive or hypovolemic patients. Superficially at this level there are no important associated structures, but the brachial artery and the median nerve are found deep to the basilic vein.

Veins of the dorsal venous network of the hand unite to form the cephalic and basilic veins, which travel along the radial and ulnar sides of the forearm, respectively (Fig. 23-3). At the midforearm level, the basilic vein crosses anterolaterally and then courses ventrally at the medial epicondyle. The medial cubital vein crosses over from the radial side of the arm to join the basilic vein just above the medial epicondyle. The basilic vein then continues proximally, where it occupies a superficial position between the biceps and pronator teres muscles. In this segment it lies in close proximity to the medial cutaneous nerve, which supplies sensation to the ulnar side of the forearm. At approximately midway in the upper part of the arm, the basilic vein perforates the deep fascia, where it joins the brachial vein and continues on into the axillary vein.20

The basilic vein is consistently found at the antecubital fossa 2 cm above and 2 to 3 cm lateral to the medial epicondyle on the anterior surface of the upper part of the arm. It is exposed through a transverse incision on the medial aspect of the proximal antecubital fossa. It is this predictability in anatomic location that makes the basilic vein an ideal site for venous cutdown in the upper extremity.

A more proximal cutdown site had previously been recommended to avoid the network of interconnecting veins at the level of the antecubital fossa.23 However, a closer association between the basilic vein and the medial cutaneous nerve in this segment may result in transection of the nerve and subsequent sensory loss on the ulnar side of the forearm.

The Cephalic Vein

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