Venous cutdown

    

This procedure exposes the vein surgically and then a cannula is inserted into the vein under direct vision. If no cannulae are available the sterile end of the drip tubing may be used in adults after cutting off the Luer (cannula) connection. The procedure must be performed under sterile conditions to avoid sepsis developing which will not only shorten the life of the infusion but may have serious consequences for the patient.

During the procedure 2 ligatures (sutures) are placed around the vein. The distal ligature is used to tie off the vein distally and the proximal ligature holds the cannula in the vein While the vein is incised the ligatures help to hold it.

Equipment

1. Sterile gloves
2. Swabs and sterile drapes
3. Skin disinfectant
4. Local anaesthetic (5ml of 0.5% lignocaine is sufficient)
5. Scalpel
6. Two small curved artery forceps
7. Sharp pointed scissors (use scalpel if scissors blunt/unavailable)
8. Ligatures (2/0 catgut / vicryl are best, but silk is adequate)
9. Skin closing sutures
10. Cannula

Sites. In adults use the upper limb at the medial aspect of the antecubital fossa. Try to avoid the leg veins as they are thicker and more prone to thrombosis, phlebitis and infection. In children a cutdown may be performed using either the brachial or long saphenous veins.

Technique. Clean the skin and use the drapes to create a sterile area around the chosen vein.

(1) Infiltrate the skin with local anaesthetic.

(2) Make a 1.5 – 2cm transverse incision over the vein (a).

(3) Bluntly dissect out the vein by opening the forceps in the line of the vein (b).

(4) Make a small stab skin incision 1cm distal to the incision in the line of the vein. Pass two ligatures around the vein. Tie the distal one, but leave the ends uncut. Hold the ends of the ligatures with the artery forceps (c).

(5) Whilst holding the ligatures tight, make a “V” shaped incision in the anterior surface of the vein with the scissors or scalpel (d).

(6) Pass the cannula through the inferior stab incision and the through the “V” shaped incision into the vein. Tie the proximal ligature tightly over the cannulated vein and, if there is no bleeding, now cut the ends of the ligatures. If bleeding occurs place a further ligature around the vein. Connect the cannula to the giving set and commence the infusion.

(7) Close the skin with sutures (f).

After the infusion is finished the cannula can be removed by a firm steady pull followed by direct pressure over the site of the incision for 5 minutes.