Central venous line insertion
This procedure can be associated with significant complications and must always be performed under supervision until competence is attained.
Commonly used sites include the internal jugular vein (IJV), subclavian vein and femoral vein. These are all located close to arteries and nerves that can be damaged by a misplaced needle, and in addition the subclavian vein lies near the pleura of the lung with the risk of pneumothorax.
The same basic principles, techniques and equipment are required for each site. The specific anatomical considerations and complications for each site are considered individually.
- Intravenous administration of specific drugs (e.g. dopamine or adrenaline)
- Inability to obtain adequate peripheral IV access in the critically unwell patient, in a timely fashion
- Central venous pressure monitoring, the insertion of a pulmonary artery (Swan-Ganz) catheter to measure wedge pressure
- Hyperalimentation (TPN administration)
- Cardiopulmonary resuscitation
- Less invasive forms of IV access are possible and adequate
- Overlying skin lesion such as cellulitis or burns
- Uncorrected bleeding diathesis
- Obstruction of the vein by tumour, mass or thrombosis
- Uncooperative patient
- Tilting trolley or bed
- Comprehensive non-invasive monitoring equipment
- Sterile drape and dressing pack, including gown
- Surgical facemask
- Appropriate central venous cannula (CVC) suitable for patient, duration and purpose, complete with its pre-prepared insertion pack. Mostly use the Seldinger insertion technique (see below)
- Needles: 25G ´1, 21G ´ 1
- Syringes: 5 mL ´ 1, 10 mL ´ 2, 20 mL ´ 1
- Lignocaine 1% or 2%
- 10 mL sodium chloride 0.9% for injection
- Disposable scalpel
- Suture material (e.g. 2-0 nylon or prolene)
- Sterile occlusive, transparent dressing (e.g. Opsite)
- Skin cleaning solution (e.g. chlorhexidine )
- IV bungs ´3
- Suture set
- Primed IV fluid line with 500 mL normal saline 0.9%
Procedural technique (Seldinger)
- Confirm with a senior doctor that central venous access is definitely needed, select the most appropriate route and explain the procedure to patient and obtain verbal consent.
- Have a trolley ready with all sterile contents laid out. Position the patient for the specific route chosen and identify the anatomical landmarks.
- Wash hands well and put on sterile gloves and gown. Use a strict aseptic technique to check and prepare central line equipment, in particular that the guidewire passes through the large-bore needle.
- Use the 10 mL syringe to draw up 10 mL normal saline and flush all the central venous cannula ports and tubing with saline.
- Use the 5 mL syringe to prepare the 1% lignocaine local anaesthetic, and cap with a sheathed 25G needle.
- Clean a wide area of skin around the insertion site with chlorhexidine using a swab held with a pair of forceps. Use a circular motion commencing at the insertion site and working from the inside out (i.e. do not return to a previously swabbed area). Dispose of swab away from sterile area and repeat. Cover the sterile area with a large fenestrated drape.
- Infiltrate the skin and deeper tissues with local anaesthetic. Work around the site and towards the vein. Remember to draw back on the plunger before injecting each time to ensure that the vein has not been penetrated.
- Attach a syringe to the large-bore insertion needle and insert through the needle into the skin. Aspirate gently while advancing the needle until the vein is entered.
- Once in the vein, ensure that you can easily aspirate blood. Remove the syringe and thread the guidewire down through the needle and into the vein. The wire should advance easily and should not need any force. Insert 20–30 cm of guidewire into the vein, but do not over-insert, as the wire may cause cardiac arrhythmias, kink or perforate the vessel wall.
- Use one hand to secure the guidewire at all times, and remove the needle. Make a 2–3-mm nick just where the wire penetrates the skin.
- Thread the dilator over the wire and into the vein with a light twisting motion. Push it firmly through the skin as far as it will go.
- Remove the dilator, being careful not to dislodge the guidewire.
- Now thread the CVC over the guidewire towards the skin. Hold the catheter steady when the tip is 2 cm above the surface of the skin, and slowly reverse the guidewire up the catheter tube away from the patient, until the wire tip appears from the line port (i.e. the central brown port).
- Holding the proximal portion of the wire protruding from the catheter port still, advance the catheter through the skin and into the vein. Take care not to allow the wire to be pushed further into the vein while advancing the catheter.
- Withdraw the wire and close off the insertion port. Check that blood can be aspirated freely from all lumens of the catheter and then flush with saline.
- Secure the catheter in place with sutures and cover with a sterile dressing. Tape any redundant tubing, carefully avoiding any kinking or loops that may snag and pull out the catheter.
- With IJV and subclavian lines order a CXR to confirm the position of the catheter tip and to exclude a pneumo-, hydro- or haemothorax. In the superior vena cava the tip of the CVP line should lie just above its junction with the right atrium.
- Early (immediate)
- Arterial puncture
- Subclavian route less likely than with IJV or femoral
- Haemorrhage from the femoral or carotid artery is much easier to control with direct pressure than from the subclavian artery.
- Arterial dissection, laceration and false aneurysm formation
- Pneumothorax, haemothorax
- Cardiac arrhythmias (usually disappear on pulling guidewire back)
- Malposition of the tip of a subclavian line, which may ascend into the IJV, or horizontally across the midline
- Injury to surrounding nerves
- Air embolism
- Loss of the guidewire (requiring radiologically guided removal).
- Arterial puncture
- Local infection—more common with femoral access than with IJV or subclavian
- Systemic infection, bacteraemia and endocarditis—more common with femoral than with IJV, which is more likely than subclavian.
- Venous thrombosis: incidence of proximal venous thrombosis is as high as 10–25% for femoral catheters left in situ for more than 24 hours
- Cardiac tamponade
- Arterial puncture
- Usually obvious, but may be missed in the hypoxic or severely hypotensive patient.
- Withdraw the needle and apply firm direct pressure to the site for at least 10 minutes or longer if there is continuing bleeding. Seek senior assistance and then retry if there is minimal swelling, or change to a different route.
- Suspected pneumothorax
- Suspect if air is easily aspirated from the syringe or the patient becomes acutely breathless.
- Stop the procedure and obtain an urgent CXR.
- If central access is absolutely necessary then try another route ON THE SAME SIDE, or one or other femoral veins. NEVER attempt either the subclavian or jugular on the other side, as bilateral pneumothorax may occur.
- Cardiac arrhythmia
- Usually occurs when the wire or catheter is inserted too far.
- Withdraw the wire or catheter.
- Do not shave hair at insertion site unless it interferes with dressing adhesive, as it may increase the risk of infection from disruption of the epidermal barrier from skin lacerations.
- Draw up normal saline in a 10-mL syringe and lignocaine in a 5-mL syringe to ensure these two agents are not mixed up during the procedure.
- Use ECG monitoring during insertion of IJV and subclavian lines.
- Rapid easy access with a high success rate, even in inexperienced hands
- Does not interfere with chest compression or airway management
- No risk of pneumothorax
- Easy to control haemorrhage with direct pressure
- Infection and thrombosis are the most commonest problems, so it cannot be recommended for long-term use
- Reduces patient’s mobility
- Easily dislodged
- Pelvic trauma or significant intra-abdominal injury
- Vascular insufficiency or trauma on same side than line is to be inserted
- CVP monitoring is required
- The femoral vein lies approximately 1 cm medial to the femoral artery within the femoral triangle of the upper thigh. The femoral artery is usually found midway along the inguinal ligament, and should be easily palpable in the groin.
- Access the vein below the level of the inguinal ligament that runs between the anterior superior iliac spine and the pubic tubercle, to avoid inadvertently entering the peritoneal cavity.
- The femoral nerve lies lateral to the femoral artery (VAN = Vein, Artery, Nerve, from medial to lateral) (see Fig. 58.1)
- Lie patient supine, with leg slightly abducted and externally rotated.
- Palpate the femoral artery 2 finger breadths below the inguinal ligament using the non-dominant hand.
- Insert the needle, bevel up, a finger breadth medial to the femoral pulsation and aim towards the umbilicus at an angle of 20–30 degrees to the skin. In adults, the vein is normally found 2–4 cm beneath the skin.
- Reduce the elevation on the needle to 10–15 degrees in small children because the vein is more superficial.
- Note: Keep a finger over the artery during the procedure to reduce the risk of arterial puncture. For the right-handed operator, the right leg is therefore easier to use.
Internal Jugular Vein
- Pneumothorax uncommon
- Easy to control haemorrhage with direct pressure
- Lower incidence of complications compared with the subclavian approach
- Carotid artery puncture relatively frequent because the IJV may overlie carotid artery to some extent in 50% of cases.
- Landmarks may be difficult to palpate in obese or oedematous patients.
- Protracted periods of Trendelenberg (head-down) tilting may not be tolerated by patients.
- Access to the IJV may be difficult in patient with a tracheostomy.
- The IJV passes vertically down the neck within the carotid sheath, initially lying posterior to the internal carotid artery, before running lateral and then anterolateral to the artery.
- It is most superficial between the heads of the sternocleidomastoid (SCM), then runs deep to join the subclavian vein behind the sternal end of the clavicle.
- Lie the patient supine with the table tilted head down. This will enhance central venous distension and reduce the risk of air embolism.
- Turn the patient’s head 30–60 degrees to the contralateral side to allow better access to the IJV.
Note: Turning the head too far laterally will increase the risk of arterial puncture.
- Stand at the head of the patient and palpate the carotid artery at the level of the cricoid cartilage, at the apex of the triangle formed by the heads of SCM.
- Keep a finger over the artery, and insert the needle bevel up at an angle of 30–40 degrees, a finger breadth lateral to the artery. Aim for the ipsilateral nipple in men and the ipsilateral anterior superior iliac spine in women.
- Always direct the needle away from the artery and keep the artery guarded under your finger.
- The vein is usually only 2–3 cm under the skin, so if the vein is not entered, re-direct the needle tip more laterally.
- Wide calibre vein (1–2 cm) in haemodynamically stable patients.
- Not affected by head movement in conscious patients.
- Useful in trauma patients with suspected cervical spine injury.
- Easy to secure with reduced rate of dislodgement.
- Low infection rate.
- Increased risk of significant complications such as pneumothorax and arterial puncture.
- Haemorrhage from accidental arterial puncture is difficult to control.
- The subclavian vein is a continuation of the axillary vein, commencing at the lower border of the first rib and draining blood from the arm.
- It is bounded medially by the posterior border of the SCM muscle, caudally by the middle third of the clavicle, and laterally by the anterior border of the trapezius muscle.
- Lie the patient supine with both arms by the sides, and the table tilted head down to distend the central veins and prevent air embolism.
- Turn the head away from the side to be cannulated. Normally, the right subclavian is cannulated. The thoracic duct is on the left and may occasionally be damaged during cannulation, resulting in a chylothorax.
- Stand beside the patient on the side to be cannulated. Identify the mid-clavicular point and the sternal notch. Insert the needle through the skin 1 cm below and lateral to the mid-clavicular point.
- Keep the needle horizontal, and advance just under the clavicle, aiming for the sternal notch. If the needle hits the clavicle aim to ‘walk off the bone’ slightly inferiorly, and direct slightly deeper to pass beneath it.
- Do not pass the needle further than the sternal head of the clavicle.
Care and use of a central line
- The line should be connected to a closed infusion system, and accessed as little as possible, to minimise the risk of infection.
- Each time the line is accessed, the injection port should be thoroughly swabbed with antiseptic solution, such as chlorhexidine, or an alcohol swab.
- When injecting through a central line, it is important to avoid inadvertent injection of air bubbles.
- Any central line that has been inserted in an emergency situation should be replaced as soon as practically possible, because of the increased risk of infection.
Measuring central venous pressure
- Ensure the infusion line is patent and that the CVP line is connected to the distal port of the CVC and the infusion solution is a crystalloid.
- Place the patient supine or with bed head up to 45 degrees.
- Measurements may be made using the right atrium as the reference point. Locate the 4th ICS at the right mid-axillary line. Place the zero mark at this point.
- Fill manometer tubing to approximately 20 cm or above the expected CVC measurement by turning the 3-way tap off to the patient.
- Exclude air bubbles from the manometer tubing.
- Turn the 3-way tap off to IV fluids.
- Wait for the fluid level to fall completely. Level should rise and fall with respiration. The reading should be taken at the lowest level.
- At the conclusion of the reading, check the 3-way tap is ‘OFF’ to the manometer; alter infusion rate to prescribed order.
- Similar landmarks are used to zero an electronic pressure transducer.
Removing a central venous catheter
- Ensure patient’s coagulation and platelet profile is within satisfactory limits.
- If sepsis is suspected, obtain the following:
- Peripheral and CVC blood cultures
- Swab from entry site if discharge present
- Catheter tip.
- Turn off and disconnect all infusions.
- Wash hands, put on sterile gloves, remove old dressing and clean around the site with chlorhexidine. Remove sutures.
- Instruct patient to hold a deep breath while the catheter is removed in a slow constant motion for IJV and subclavian lines. This increases intrathoracic pressure and prevents air embolism.
- Apply firm pressure over the exit site with a sterile gauze swab for at least 5 minutes.
- Inspect the catheter for completeness.
- Apply an occlusive dressing over the exit site for 48 hours.
- Central Venous Line (CVL) – SCGH Recommended Fixation Standard
- SCGH ICU Central Line Insertion Guideline developed in late 2015 (this includes a link to the NEJM Central Venous Catheterization Video).