Anatomy

see Vascular Access Anatomy

What veins are most commonly approached for peripheral intravenous access?

Head and neck

• Scalp veins are a consideration only in neonates.
• The external jugular vein, even when temptingly visible, is notoriously difficult to access because it is quite mobile and easily compressed.

Hands and arms

• The brachial, basilic and cephalic veins of the arm are often accessed. However, care should be taken that the catheter does not cross the antecubital fossa unless the elbow can be immobilized.
• Numerous veins are present on the dorsum of the hand and wrist. Those on the volar surface of the wrist should generally be avoided.
  • The basilic vein is reliably located between the distal and proximal heads of the fourth and fifth metacarpal bones.
  • The cephalic vein is found by directing an intravenous catheter from between the base of the thumb and the index finger to just posterior to the distal head of the radius. The greater saphenous vein is often seen or palpated as it passes just anterior to the medial malleolus. It is best accessed by plantar flexing the foot and advancing the intravenous catheter from a point a centimeter or two distal to the medial malleolus and in line with the great toe toward the anterior malleolus. Placing the tip of your contralateral thumb directly on the medial malleolus and rolling your thumb anteriorly will leave an indentation from your thumbnail directly over the greater saphenous vein.

Feet and legs

• The lesser saphenous vein runs anterior to the medial malleolus, while the small saphenous vein crosses the lateral malleolus.

The location of other veins of the feet and hands, although often useful, are quite variable.

What veins are most commonly approached for cut down venous access?

The four veins most suitable for central venous access by cutdown are the external and internal jugular veins, the common facial vein and the saphenous vein at the groin. Cut down onto the common femoral vein is seldom necessary.

• The external jugular vein runs subcutaneously from the angle of the jaw to the clavicle where it enters the subclavian vein. A small incision is made directly over the vein low in the neck. As it is subcutaneous, the vein is easily exposed, isolated between fine ties and ligated cephalad. The catheter tip should be beveled at forty-five degrees and the catheter introduced into the vein with its bevel facing downward.
• The internal jugular vein runs from the jugular foramen at the base of the skull to its confluence with the subclavian vein just deep to the medial head of the clavicle. A direct approach to this vein is through a neck incision between the sternal and clavicular heads of the sternocleidomastoid muscle. If an attempt to access the external jugular vein has been unsuccessful the internal jugular vein may be approached through this more lateral incision by retracting the clavicular head of the sternocleidomastoid muscle anteriorly. The vein is isolated between ties and brought out through the incision. Ligation cephalad should seldom be necessary. Rather, a pursestring suture of 7-0 polypropylene may be placed in the vein, the catheter introduced through a venotomy in the center of the pursestring and the pursestring tied. Alternatively a small venotomy may be made, the catheter placed, and the venotomy closed around the catheter with 7-0 polypropylene suture. With experience the catheter may also be placed through a tiny venipuncture made with a 14 or 16 g tunneling needle with little bleeding around the site. Regardless of the method used such approaches allow one to avoid ligation of the internal jugular vein.
• The common facial vein is an anterior branch of the internal jugular vein. It courses anterior to the external carotid artery and enters the internal jugular vein below the level of the hyoid bone at approximately the midpoint between the inferior edge of the ear and the sternal notch. It is relatively easy to identify the internal jugular vein and to follow it to the common facial vein. Use of the common facial vein has the advantage of sparing the internal jugular vein.
• The proximal greater saphenous vein crosses the medial aspect of the knee one third of the distance from posterior to anterior and courses anteriorly/laterally before entering the fascia lata at the saphenofemoral junction. It joins the common femoral vein in the region of the femoral triangle. A transverse incision is made about two centimeters below the inguinal ligament, medial to the femoral pulsation. As the saphenous vein runs subcutaneously, it is easily exposed, isolated between fine ties and ligated distally. A tiny venotomy is made close to the ligature. The beveled catheter tip is introduced and slowly advanced. Once past the saphenofemoral junction the catheter should pass easily.