MAURO PITTIRUTI and ANTONIO LAGRECA

Overview

Standard central venous access performed with the “blind” technique was historically based on the puncture of two central veins (the subclavian vein and the internal jugular vein),¹ but ultrasound (US) guidance has expanded the spectrum to at least four sites: the internal jugular vein, the brachiocephalic (or “innominate”) vein, the subclavian vein, and the axillary vein. In many patients, two additional, centrally located venous segments can be cannulated: the external jugular vein (in its final tract close to the junction of the subclavian vein) and the cephalic vein (in its final, infraclavicular tract close to the junction of the axillary vein).

The list just presented is limited to the veins available for placement of central venous catheters (CVCs) in the neck/thoracic area. However, other peripheral veins can be used for US-guided cannulation and placement of a peripherally inserted central catheter in the upper part of the arm (the cephalic vein, the brachial veins, the basilic vein, and the axillary vein in its distal tract). Other peripheral veins located in the groin area (the femoral and saphenous veins) can be accessed for placing “central” venous catheters.

The shift from a “heads-or-tails” choice (subclavian vs. jugular) to a wide spectrum of choices (internal jugular, brachiocephalic, subclavian, axillary, etc.) is the real “Copernican” revolution of the US era. Whereas in the last century the physician was bound to choose between the subclavian and jugular sites on the basis of personal preference, instinct, or experience, selection of the most appropriate vein to cannulate can be determined today on a rational basis by means of US technology.²

The rapid central vein assessment

US guidance is an evidence-based methodology that significantly reduces the complications related to insertion of CVCs.3–5 However, the benefit of using US is not limited to real-time US-guided venipuncture. The GAVeCeLT (Italian Group for Venous Access Devices) recommended the use of US during CVC insertion for six different purposes: (1) US evaluation of all veins available, (2) choice of the vein on the basis of rational US-based criteria, (3) real-time US-guided venipuncture, (4) US-based control of guidewire/catheter orientation during the procedure, (5) US-based control of pleura-pulmonary integrity after axillary or subclavian vein puncture, and (6) transthoracic echocardiography for verification of the position of the tip of the catheter at the end of the procedure.

Of particular relevance is the application of US for rapid assessment of the central veins in an effort not only to exclude veins that appear morphologically abnormal (thrombosis, external compression, anatomic variations) but also to evaluate the possible options and choose the best approach. This can easily be performed by following the rapid central vein assessment (RaCeVA) protocol, which has been standardized by our group and is currently taught in our GAVeCeLT courses on US-guided central venous access.

This six-step protocol suggests the following preprocedural complete venous scan (before deciding on the most appropriate approach):