Indications
- Ongoing CPR — the femoral site can be accessed without interrupting chest compressions or airway management, unlike the neck.
- Neck access unavailable — cervical collar in situ, local infection, distorted anatomy, or a failed internal jugular attempt.
- Large-bore access for rapid volume resuscitation (major haemorrhage) where upper body sites are difficult.
- Renal replacement therapy access placed by critical care, where femoral is sometimes preferred short-term.
Contraindications & cautions
Relative contraindications
- Groin infection, overlying burn or wound.
- Known ipsilateral femoral vein thrombosis or IVC filter.
- Coagulopathy — femoral is a non-compressible-adjacent site; correct where urgency allows and prefer ultrasound guidance.
Cautions
- No absolute contraindication in cardiac arrest or exsanguinating haemorrhage.
- Femoral hernia or vascular graft in the region.
- Higher infection risk than upper-body sites with prolonged use — remove as soon as an alternative is established.
Equipment
Anatomy — NAVY
Below the inguinal ligament, structures in the femoral triangle run, lateral to medial: Nerve, Artery, Vein — the mnemonic "NAVY" adds the empty space and lymphatics medially. The vein lies just medial to the palpable femoral pulse.
Step-by-step technique
Position
Supine, leg slightly abducted and externally rotated. Palpate the femoral pulse roughly 2 cm below the inguinal ligament (mid-inguinal point, halfway between the anterior superior iliac spine and pubic symphysis).
Ultrasound scan
Ultrasound guidance is strongly preferred over landmark technique — it directly visualises the vein, confirms patency, and reduces arterial puncture and failed attempts. Identify the vein (compressible, medial to the artery) in short-axis view.
Prepare
Full aseptic technique — chlorhexidine skin prep, sterile drapes, gown and gloves. Local anaesthetic infiltration in the conscious patient.
LAST rescue — AAGBI algorithm ↗Needle puncture
Advance the introducer needle at roughly 45° under direct ultrasound visualisation (or, if landmark technique in extremis, just medial to the palpated pulse), aspirating continuously until dark, non-pulsatile venous blood returns.
Guidewire
Remove the syringe, feed the wire smoothly — it should pass without resistance. Never let go of the wire. Confirm intravenous wire position with ultrasound if any doubt.
Dilate and insert catheter
Small skin nick, dilate over the wire, then advance the catheter over the wire to the appropriate depth, remove the wire, and confirm venous return from all lumens with easy aspiration.
Secure and confirm
Suture, dress, flush all lumens. Confirm position with ultrasound; a formal chest X-ray is not required for femoral lines (unlike IJ/subclavian), but document clearly.
Complications
Early
- Arterial puncture — the vein sits immediately medial to the artery; apply firm pressure if this occurs.
- Failure to cannulate, or guidewire misdirection into a tributary.
- Retroperitoneal haematoma from a high or posterior puncture above the inguinal ligament.
- Nerve injury (uncommon, femoral nerve lies lateral to the target).
Late
- Deep vein thrombosis — higher risk than upper-body central lines, increasing with dwell time.
- Catheter-related infection — higher rate than subclavian or IJ sites, particularly in the groin crease.
- Line malfunction from hip flexion kinking the catheter.
When to prefer IO instead
- In cardiac arrest, intraosseous access is the pragmatic first-line route when IV access is not rapidly achievable — it is faster to establish, does not require interrupting compressions, and is technically simpler under pressure. See the intraosseous access page.
- Femoral venous access is typically reserved for when IO access is unsuitable, has failed, or when a definitive central line is needed for ongoing critical care.
- Femoral access does not require interruption of CPR, making it a reasonable alternative to IO if an operator skilled in the technique is available without compromising resuscitation.
Pitfalls & pearls
- Puncture too high (above the inguinal ligament) risks a retroperitoneal bleed that is hard to control — stay below the ligament.
- Ultrasound guidance meaningfully reduces arterial puncture compared with landmark technique — use it whenever available, even in an emergency.
- Femoral lines are for stabilisation, not for the duration of an admission — plan early conversion to an upper-body site.
- In arrest, don't let attempts at femoral access interrupt chest compressions — IO is usually faster and simpler.
DOPS pointers
RCEM curriculum: Core Procedural Skill. What assessors look for at each entrustment level:
| 1 | Observed only — can describe NAVY anatomy and the safe puncture zone below the inguinal ligament. |
| 2a | Performs with supervisor scrubbed alongside: correct ultrasound identification of the vein, controlled wire insertion. |
| 2b | Performs with supervisor in the department: full Seldinger sequence, securing and documentation. |
| 3 | Indirect supervision: manages arterial puncture, difficult wire passage, and decides when femoral access is preferable to IO or IJ. |
| 4 | Independent; can teach and supervise, including in the peri-arrest setting. |
References
- Resuscitation Council UK. Adult Advanced Life Support Guidelines, 2021 — vascular access during CPR.
- NICE. Guidance on the use of ultrasound locating devices for placing central venous catheters (TA49) — note its recommendations are scoped to internal jugular insertion; ultrasound guidance at the femoral site is extrapolated by analogy and supported by wider vascular-access literature.
- RCEM Curriculum 2021 — Emergency Medicine Specialty Learning Outcomes: core procedural skills (DOPS).