Femoral vein anatomy for central line insertion

This came up in Question 3 from the first paper of 2005: "Outline the anatomical structures relevant to the insertion of a femoral venous catheter."

Here is a classic diagram to help one remember.

The femoral vein lies within the femoral triangle:

• The superior border is formed by the inguinal ligament.
• The medial border is formed by the adductor longus.
• The lateral border by the sartorius muscle.
• The apex is formed by the sartorius crossing the adductor longus muscle.
• The roof is composed of the skin, subcutaneous tissue, the cribriform fascia, and the fascia lata.
• The floor is formed of underlying adductor longus, adductor brevis, pectineus, and iliopsoas muscles.
• Lateral to the femoral vein is the femoral artery in a fibrous sheath
• Medial to the femoral vein is the fatty lymphatic contents of the femoral sheath.

The insertion point of the femoral CVC is:

• 1cm inferior to the inguinal ligament
• 1cm medial to the maximal pulse of the femoral artery

Critically important issues:

Ensure that the puncture of the vein occurs below the level of the inguinal ligament.

Puncture above the inguinal ligament is in fact a puncture of the external iliac vein.

The external iliac vein ends up being as deep retroperitoneal structure; if it is lacerated and begins to bleed, it will be impossible to place pressure on the puncture wound.

Embarrassing retroperitoneal haematoma will result.

If one selected the femoral vessels as a favourable site because of concerns regarding coagulopathy, a puncture of the external iliac vein will completely obliterate any possible haemostatic benefit. You may as well have gone for a subclavian vessel- at least a haemothorax is accessible via a chest drain.