Arterial Line Placement 

Updated: Jun 19, 2020
Author: Sarah Ogle, DO, MS; Chief Editor: Vincent Lopez Rowe, MD 

Overview

Background

Arterial line placement is a common procedure in various critical care and some anesthetic settings. Intra-arterial blood pressure (BP) measurement is more accurate than measurement of BP by noninvasive means, especially in the critically ill.[1] Intra-arterial BP management allows rapid recognition of BP changes, which is especially vital for patients receiving continuous infusions of vasoactive drugs. Arterial cannulation allows repeated arterial blood gas samples to be drawn.

Arterial line placement is a safe procedure. Major complications occur in fewer than 1% of placements.[2]  Risks can be minimized with appropriate knowledge of the anatomy and procedural skills. Arterial lines can be placed in the radial, ulnar, brachial, axillary, posterior tibial, femoral, and dorsalis pedis arteries.

In both adults and children, the most common site of cannulation is the radial artery.[2, 3, 4] The superficial and consistent anatomic location of the radial artery affords easier access, facilitates care, and yields fewer complications.[4]  

The femoral artery is the second most common site for arterial cannulation. One advantage of femoral artery cannulation is that the vessel is larger than the radial artery and has stronger pulsation. Additional advantages include decreased risks of thrombosis and of accidental catheter dislodgment.[5]  

There is debate over whether radial or femoral arterial line placement more accurately measures BP and mean arterial pressure (MAP); however, both sites provide reliable data.[6, 7, 8]  The arterial cannulation site is patient-specific and is determined on the basis of the anatomy, the risks and benefits, and the indication for the procedure.

Indications

Indications for arterial line placement are as follows:

  • Continuous direct BP monitoring - Arterial catheter MAP measurements are even more accurate than sphygmomanometric BP readings in patients who are morbidly obese, are very thin, have severe extremity burns, or are hypotensive [9]
  • Frequent blood sampling ( arterial blood gas sampling)

Placement of an arterial line can help prevent complications associated with repeated arterial puncture (eg, pain, hematoma).

Contraindications

Absolute contraindications for arterial line placement are as follows[9, 10] :

Relative contraindications are as follows[9, 10] :

  • Anticoagulation
  • Coagulopathy
  • Inadequate collateral flow
  • Infection at the cannulation site
  • Partial-thickness burn at the cannulation site
  • Previous surgery in the area
  • Synthetic vascular graft

Technical Considerations

Anatomy

The radial artery originates in the cubital fossa from the brachial artery (see the image below). It traverses the lateral aspect of the forearm and gives rise to the palmar arches that provide vascular flow for the hand. At the wrist, the radial artery sits proximal and medial to the radial styloid process and just lateral to the flexor carpi radialis (FCR) tendon.

Anatomy of radial artery. Anatomy of radial artery.

The initial puncture site for radial arterial cannulation should be as distal as possible on the wrist. A common location is over the radial pulse at the proximal flexor crease of the wrist. The puncture site should be at least 1 cm proximal to the styloid process so as to prevent puncture of the retinaculum flexorum and the small superficial branch of the radial artery.

The femoral artery originates at the inguinal ligament from the external iliac artery (see the image below). The artery passes under the inguinal ligament at approximately the midpoint between the anterior superior iliac spine and the pubic tubercle. It lies medial to the femoral nerve and lateral to the femoral vein and lymphatics.

Anatomy of femoral triangle. Anatomy of femoral triangle.

To facilitate control of bleeding and prevent bleeding into the pelvis, the femoral artery always should be accessed approximately 2.5 cm below the inguinal ligament. The artery is more easily palpable at this location and can be compressed. 

Best practices

The following measures and recommendations may facilitate placement of an arterial line:

  • Ultrasonographic (US) guidance is recommended for identifying and accessing the target vessel, especially at the femoral location
  • Doppler US alone can also facilitate arterial cannulation
  • Appropriately position the patient and feel arterial pulsation before initiating arterial line placement
  • Flush the needle introducer with heparinized flush to facilitate flashback of blood up to the needle hub upon entry into the artery
  • Puncture the radial artery in a slight lateral-to-medial direction to stabilize it against the FCR tendon
  • After arterial puncture or decannulation, maintain pressure over the puncture site for at least 5 minutes (or possibly longer if the patient is coagulopathic or anticoagulated)
  • Make a small skin incision at the site of needle puncture to allow easier passage of the catheter through the skin and help prevent catheter kinking during advancement [3]
  • When using a catheter-over-needle technique, be sure to advance the needle 2 mm after flash to ensure catheter placement inside the lumen
  • When using a Seldinger technique, do not dilate the artery; to minimize bleeding and vessel injury, dilate only the soft-tissue tract
  • If the guide wire cannot be passed into the artery, try rotating the needle 90-180° in an attempt to eliminate an intimal flap blocking passage of the wire
  • To avoid creating false passages, do not force advancement if passage of a guide wire or catheter meets resistance 
  • When it proves difficult to advance the catheter into the lumen, consider the “liquid stylet” method; fill a 10-mL syringe with 5 mL of sterile normal saline, attach it to the catheter hub, aspirate 1-2 mL of blood into the syringe, and then slowly inject the syringe contents into the vessel as the catheter is advanced behind the fluid wave [11]
  • If several attempts at cannulation fail, the artery may spasm, making further attempts more difficult; if this occurs, allow the artery to recover for a short time before reattempting cannulation; subcutaneous infiltration of lidocaine or similar anesthetic around the puncture site may reduce vessel spasm [3]
  • Check the pulse waveform on the monitor to ensure that a good waveform is obtained; a pulse waveform that appears dampened initially may be secondary to arterial spasm; if this occurs, wait for the arterial spasm to resolve
  • Consider adding papaverine 30 mg/250 mL to the arterial line fluid, this may prolong the patency of peripheral arterial catheters in children and neonates [12, 13]
  • Regularly inspect the area for signs of ischemia, and remove the catheter at the first signs of circulatory compromise or clot formation; do not flush the catheter in an attempt to remove clots
  • To reduce the complication rate, remove the catheter as soon as it is no longer necessary [14]  
 

Periprocedural Care

Equipment

Several commercially available kits contain all the supplies necessary for arterial line placement. These include the Arrow UM-04018, for Seldinger-technique femoral lines, and the Arrow AK-04020 with integrated wire, for modified Seldinger-technique radial lines (Arrow International, a division of Teleflex Medical, Research Triangle Park, NC).

Devices and supplies required may include the following:

  • Ultrasound probe - 5-13 MHz linear array
  • Sterile ultrasound probe kit with sterile lubrication
  • Sterile gloves
  • Sterile gauze (4 × 4 cm)
  • Sterile towels
  • Chlorhexidine or povidone-iodine skin preparation solution
  • 1% Lidocaine without epinephrine in a 3- to 5-mL syringe with a 25- to 27-gauge needle
  • 5-mL syringe with heparinized flush
  • Appropriate-sized cannula for artery
  • Scalpel (No. 11 blade)
  • Nonabsorbable suture (3-0 to 4-0)
  • Adhesive tape or strips
  • Sterile nonabsorbable dressing
  • Three-way stopcock
  • Pressure transducer kit
  • Pressure tubing
  • Arm board of appropriate size for the patient (eg, neonate, pediatric, adult)
  • Needle driver
  • Intravenous (IV) tubing T-connector

Radial artery

Equipment for radial artery cannulation may include the following:

  • Catheter-over-needle technique - 20-gauge, 1.75-in. (4.45-cm) polyurethane catheter over 22-gauge introducer needle
  • Catheter-over-wire technique (Seldinger) - 20-gauge peripheral artery catheter kit with 20-gauge catheter, 22-gauge introducer needle, and compatible soft-tip wire (see the image below)
  • Catheter-over-wire technique (modified Seldinger) - 20-gauge peripheral artery catheter kit with integrated wire and catheter

Whereas a 20-gauge peripheral artery catheter kit is suitable for large children and adult patients, a 22- to 24-gauge angiocatheter is preferable for infants and neonates.

Radial artery cannulation (Seldinger). Catheter-ov Radial artery cannulation (Seldinger). Catheter-over-wire arterial line kit.

Femoral artery

Commercial kits for the Seldinger technique (catheter-over-wire) are not generally available in the United States. Recommended equipment for catheter-over-wire femoral artery cannulation (see the image below) may include the following:

  • 18-gauge, 3-in. (7.6-cm) introducer needle
  • 18- or 20-gauge, 1.5-in. (3.8 cm) or 3-in. needle (an 18-gauge spinal needle will usually suffice)
  • Guide wire, appropriately sized for the catheter (eg, 45 cm in length and 0.64 mm in diameter); it should have a straight soft tip on one end and a J tip on the other
  • Plastic spring wire insertion adapter to straighten the J-tip end of the guide wire for insertion into the plastic catheter
  • 18- or 20-gauge catheter, 15 cm or longer
Femoral artery cannulation (modified Seldinger). C Femoral artery cannulation (modified Seldinger). Catheter-over-wire arterial line kit.

Patient Preparation

Preparation of the patient for arterial line placement includes selection of the appropriate site and approach technique for catheter insertion (see Technique), as well as anesthesia, positioning, and creation of a sterile field (see below). 

Anesthesia

In an emergency situation or when the patient is unresponsive, anesthesia is not required. In a conscious patient, local anesthesia can be provided by using a small amount of lidocaine 1% at the puncture site to prevent obscuring the site. Lidocaine with epinephrine should be avoided because it can constrict the artery, making cannulation more difficult.A lidocaine-tetracaine patch may also be an option for local anesthesia and obviates the need for subcutaneous infiltration.[15]  (See Local Anesthetic Agents, Infiltrative Administration.)

If the patient is combative or if maintaining stability of the extremity is difficult, sedation or general anesthesia may be required. (See Procedural Sedation.)

Positioning

For radial artery cannulation, the patient is placed in the supine position. The arm is placed up on a flat surface in neutral position with the palm up and the wrist adequately exposed. The wrist is dorsiflexed to 30-45° and supported in this position with a towel or gauze under its dorsal aspect (see the image below). Hyperdorsiflexion should be avoided; this maneuver can compress the radial artery, making cannulation more difficult. Positioning is maintained by having an assistant hold the patient’s hand or by taping the hand and fingers to the work surface.

Wrist position for radial artery line placement. Wrist position for radial artery line placement.

For femoral artery cannulation, the patient is also placed in the supine position, with the hip in mild external rotation. The artery is palpated at the midpoint between the anterior superior iliac spine and the pubic tubercle.

Creation of sterile field

After the target vessel is selected, the area should be prepared with either chlorhexidine gluconate or povidone-iodine ophthalmic solution 5% and draped with sterile towels or drapes. Because arterial catheters can be a source of bloodstream infections, sterile technique must not be overlooked.[14] Operators should don sterile gloves, a mask, and hair covering. When the procedure is done under ultrasonographic (US) guidance, a sterile probe cover and gel should also be utilized. After the equipment is inspected, it should be maintained on the sterile field. The vessel should then be reidentified by means of palpation or US after the sterile field has been assembled.

 

Technique

Approach Considerations

Identification of vessels

Once the patient is properly positioned, palpate the artery, and confirm with ultrasonography (US) or Doppler US. US can be particularly helpful for identifying and accessing arteries in patients who have small vessels, have had previous arterial lines or attempts in the same area, or are hypotensive.[4, 16, 17, 18, 19, 20, 21, 22, 23] US guidance reduces the number of attempts, shortens the time to cannulation, reduces complications, and identifies anatomic variations.[4, 16, 17, 18, 19, 20, 21, 22, 24]  US can also help distinguish veins, which collapse with gentle pressure of the probe, from pulsating arteries.

Given the increasing availability of US for bedside use, it is reasonable to recommend that US guidance be employed when available.[20] Barriers identified as prohibiting the use of US guidance for vascular access include lack of equipment, perceived increases in procedure time, and concern regarding possible loss of traditional vessel identification skills.[25] If standard US is not available, a handheld Doppler device can facilitate location of the artery.

Vessels can be visualized both out of plane (short axis, perpendicular to the vessel) and in plane (long axis, parallel to the vessel). Both approaches guide cannulation. The short axis is useful for identifying surrounding structures; however, the operator must be mindful of advancing the probe along the vessel to maintain visualization of the needle tip while accessing the vessel. The long axis is useful for visualizing the continuous length while the vessel is being cannulated.[20]

Choice of site and approach

Arterial line placement can be performed via multiple methods. The choice of methods is determined by location, operator preference, and available equipment. The most commonly used methods are the following[26] :

  • Catheter over needle
  • Catheter over wire (including direct Seldinger and modified Seldinger techniques)

Arterial cutdown for arterial access is not recommended. It should be considered a last resort, to be performed only by physicians with sufficient training and skill to perform the procedure and manage complications. Discussion of cutdown technique is beyond the scope of this article.

For radial artery cannulation, either the catheter-over-needle technique or the catheter-over-wire technique may be used. The latter is more common in adults and larger children; the former is more common in infants and neonates. As a last resort, a surgical cutdown can be performed for cannulation of the radial artery.

For femoral artery cannulation, the catheter-over-wire technique is preferred. The puncture site for the femoral artery should be below the inguinal ligament to allow control of bleeding and prevention of bleeding into the pelvis. The catheter-over-needle technique can also be used for femoral artery cannulation, either alone or in combination with an over-the-wire technique (ie, Seldinger) if a longer indwelling catheter is desired.

Allen Test

Many experts recommend that an Allen test be performed before radial artery cannulation is initiated. This procedure is a simple bedside test designed to evaluate for adequate collateral circulation to the palmar arches of the hand. In most patients, the palmar arches are supplied by both the radial artery and the ulnar artery. This collateral circulation allows perfusion of the hand should either of these vessels be injured.

To perform this test, the examiner elevates the hand and asks the patient to make a fist for 30 seconds. With the patient’s hand in a fist, the examiner applies simultaneous pressure to the ulnar and radial arteries so as to occlude them (see the image below).

Allen test. Examiner occludes both radial and ulna Allen test. Examiner occludes both radial and ulnar arteries while patient makes fist.

The patient is then asked to open the hand, which should appear blanched as a consequence of the occlusion of the radial and ulnar arteries (see the image below).

Allen test. Radial and ulnar arteries remain occlu Allen test. Radial and ulnar arteries remain occluded after hand is opened.

Next, the pressure over the ulnar artery is released (see the image below), and the time it takes for color to return to the hand is measured (in seconds).

Allen test. Pressure on ulnar artery is released, Allen test. Pressure on ulnar artery is released, and time to observed return of color to hand is measured.

A modified Allen test has been described for use in unconscious or anesthetized patients who are unable to make a fist on demand.[3, 27]  In this variant, an Esmarch bandage is used to exsanguinate the hand; the rest of the test is performed as already described.

According to one view, Allen test results may be interpreted as follows[3] :

  • If color returns to the hand within 5 seconds, the result of the Allen test is negative (normal) and the radial artery can safely be cannulated
  • If color does not return to the palm within 5 seconds, the test result is positive (abnormal), in which case the collateral blood supply to the hand may be insufficient and an alternate cannulation site may be warranted

According to another view, Allen test results may be divided into the following three categories[10] :

  • Return of perfusion to the hand in less than 7 seconds - Normal
  • Return of perfusion in 8-14 seconds - Equivocal
  • Return of perfusion in more than 14 seconds - Abnormal

In addition to disagreement about precisely what constitutes an abnormal result, there is some debate in the literature about whether an Allen test is needed before radial artery puncture and how well it predicts complications. Patients with abnormal test results have safely undergone radial artery cannulation, and patients with normal results have experienced hand ischemia.[28, 29]

Overall, although the Allen test is not perfect, it should be performed before arterial puncture if time permits, and alternative puncture sites should be considered if the results are abnormal. Given the controversy surrounding the results of this test, however, some experts recommend Doppler evaluation of collateral flow in all high-risk patients before cannulation.[30]

Catheter-Over-Needle Technique

The catheter-over-needle approach is the most basic method for placing an arterial line. Much as with peripheral intravenous (IV) placement, a needle with an integrated catheter is placed into the arterial lumen, and the catheter is advanced over the needle. This technique is best suited for use when the artery is located superficially, as is the case with the radial artery. It is the preferred method for radial artery cannulation in neonates and infants; the small vessel diameter in these patients makes threading a guide wire into the vessel lumen difficult.

For the catheter-over-needle approach, position the patient as described previously (see Patient Preparation). Identify the artery by means of palpation or US (or both). Clean the area with povidone-iodine or chlorhexidine, don sterile gloves in a sterile fashion, and drape the field with sterile towels or drapes.

Palpate the artery with the second and third digits (see the image below; the hand is left undraped to provide orientation), or visualize the artery with an ultrasound device in your nondominant hand. Inject 1-2 mL of lidocaine 1% without epinephrine at the site of insertion. Make sure not to distort the anatomy with a significant skin wheal.

Radial artery cannulation (modified Seldinger). Ra Radial artery cannulation (modified Seldinger). Radial artery prepared and draped in sterile fashion.
Radial artery cannulation. Palpation of radial art Radial artery cannulation. Palpation of radial artery.

Puncture the skin proximal to your fingers over arterial pulsations, advancing the needle at a 30-45° angle toward the pulsation with its bevel facing up (see the images below). If the artery is not punctured, make sure to withdraw the needle back to the skin before repositioning the needle. When employing US guidance, remember to follow the tip of the ultrasound device with the tip of the needle in the short-axis view. The long-axis view can be advantageous in that it allows visualization of the length of the artery and needle during cannulation.

Radial artery cannulation (catheter over needle). Radial artery cannulation (catheter over needle). Catheter introduction through skin.
Femoral artery cannulation (catheter over needle). Femoral artery cannulation (catheter over needle). Insertion of 20-gauge, 1.75-in. catheter over needle into femoral artery. Note 45° insertion angle.

Observe the hub of the needle for a flash of bright red blood, which signifies arterial puncture (see the images below). Once a flash has been obtained, lower the needle-catheter assembly to an angle of 10-20° from the skin, and insert the needle 1-2 mm further to advance the catheter into the lumen of the artery.

Radial artery cannulation (catheter over needle). Radial artery cannulation (catheter over needle). Puncture of radial artery.

Stabilize the needle, and advance the catheter over the needle into the artery until the hub is at the level of the skin. If any resistance is felt, reposition the needle until free blood flow is obtained, and then try to advance the catheter. Never pull the catheter back over the needle; this can shear the catheter tip and lead to embolization of the catheter or a foreign body in the subcutaneous tissues.

Radial artery cannulation (catheter over needle). Radial artery cannulation (catheter over needle). Stabilization of catheter while needle introducer is removed.
Radial artery cannulation (catheter over needle). Radial artery cannulation (catheter over needle). Catheter advanced into radial artery.

After the catheter has been advanced into the artery, remove the needle and attach the catheter to an appropriate arterial line tubing (see the image below).

Femoral artery cannulation (catheter over needle). Femoral artery cannulation (catheter over needle). Removal of needle after artery has been cannulated and catheter has been inserted into lumen of artery.

 Secure the catheter in place with sutures, tape, or adhesive strips, and apply a semipermeable sterile dressing over the site (see the images below).

Radial artery cannulation (catheter over needle). Radial artery cannulation (catheter over needle). Radial artery catheter secured in place with Steri-Strips.
Radial artery cannulation (catheter over needle). Radial artery cannulation (catheter over needle). Sterile dressing applied over radial artery cannula.

If the catheter cannot be advanced into the lumen but free return of blood exists, attempt to cannulate the vessel by using a guide wire and placing the catheter over the wire (see Catheter-Over-Wire Technique ). If a longer catheter is desired, the catheter-over-needle technique can be combined with the catheter-over-wire technique (see Catheter-Over-Wire Technique and Combination Technique).

Catheter-Over-Wire Technique

The other main option for arterial line placement is the catheter-over-wire method, which includes the Seldinger and modified Seldinger techniques. The Seldinger and modified Seldinger techniques are similar in that they both involve entering the artery with a needle, advancing a wire into the artery through the needle, and then threading a catheter over the wire into the artery. Whereas the Seldinger technique uses separate components, the modified Seldinger technique uses an integrated needle-catheter-wire system.

Catheter-over-wire techniques can be used for superficial arteries (eg, the radial artery) and are preferred for the femoral artery. This method should not be used routinely for radial artery cannulation in neonates and infants, because the diameter of the vessel is too small to allow easy advancement of the guide wire.

Seldinger technique

Position, prepare, and drape the patient as previously described. Inject local anesthetic. Open the arterial line kit, and check the guide wire to make sure that it flows freely through the introducer needle. Palpate the artery with the second and third digits of the nondominant hand (see the image below).

Radial artery cannulation (Seldinger). Palpation o Radial artery cannulation (Seldinger). Palpation of radial artery.

Attach the finder needle to a syringe. Puncture the skin proximal to your fingers over arterial pulsations, advancing the needle at a 30-45° angle toward the pulsation (see the images below). Sometimes, making a small puncture in the epidermis with a larger needle at the site of the desired cannulation will decrease friction.

Radial artery cannulation (Seldinger). Puncture of Radial artery cannulation (Seldinger). Puncture of skin with finder needle.
Femoral artery cannulation (Seldinger). Puncture o Femoral artery cannulation (Seldinger). Puncture of femoral artery with 18-gauge, 3-in. hollow introducer needle. Note 45° insertion angle.

Advance the needle with slight negative pressure until free return of blood is visualized in the syringe (see the image below). If initial return of blood is observed but the flow then ceases, the posterior wall of the vessel may have been punctured. Withdraw the needle slightly to try to restore blood flow to the needle.

Radial artery cannulation (Seldinger). Puncture of Radial artery cannulation (Seldinger). Puncture of radial artery with return of blood.

Once free flow of blood is obtained, remove the syringe.  Advance the guide wire into the artery (see the images below). If any resistance is encountered in advancing the guide wire, stop advancing the wire, reposition the needle, and attempt to cannulate the vessel again. If any resistance to repositioning the guide wire in the needle is met or if the guide wire is stuck in the needle, remove the needle and the wire together and start again.

Radial artery cannulation (Seldinger). Introductio Radial artery cannulation (Seldinger). Introduction of guide wire into radial artery.
Femoral artery cannulation (combination technique) Femoral artery cannulation (combination technique). Insertion of guide wire through catheter into femoral artery lumen.

Before removing the needle, make a small skin incision with a scalpel at the site of needle entry into the skin (see the images below). Do not make a stab incision of the sort used in central line placement; such an incision may damage the underlying artery.

Radial artery cannulation (Seldinger). Skin incisi Radial artery cannulation (Seldinger). Skin incision over needle.
Femoral artery cannulation (Seldinger). 2-mm incis Femoral artery cannulation (Seldinger). 2-mm incision is made next to guide wire with No. 11 scalpel blade.

Remove the needle while holding the guide wire in place. Then, advance a catheter over the wire into the artery (see the images below). If advancement of the catheter becomes difficult, a twisting motion can be used to facilitate catheter passage. A dilator is usually not necessary; if it is used, it should be employed only to dilate the tract, not to enter the artery; the latter can cause excessive bleeding.

Radial artery cannulation (Seldinger). Advancement Radial artery cannulation (Seldinger). Advancement of catheter over guide wire.
Femoral artery cannulation (Seldinger). Insertion Femoral artery cannulation (Seldinger). Insertion of 20-gauge, 5-in. catheter over guide wire into femoral artery.

Once the catheter is in place, remove the guide wire. Appropriate positioning of the catheter is confirmed by return of pulsatile blood from the catheter hub. Attach the catheter to appropriate arterial line tubing (see the image below). Secure the catheter in place with sutures, tape, or occlusive dressing.

Radial artery cannulation (Seldinger). Attachment Radial artery cannulation (Seldinger). Attachment of arterial line tubing to catheter.

Modified Seldinger technique

The modified Seldinger technique is similar to the standard Seldinger technique; however, the needle, catheter, and guide wire are all parts of a single unit. The description below addresses the use of this technique for line placement in the radial artery. Position, prepare, and drape the patient as previously described. Inject local anesthetic. Open the arterial line kit. Assemble the catheter and wire (see the first image below). Make sure the guide wire moves smoothly and confirm that the wire is fully retracted (see the second image below).

Radial artery cannulation (modified Seldinger). Ca Radial artery cannulation (modified Seldinger). Catheter and wire assembled.
Radial artery cannulation (modified Seldinger). Wi Radial artery cannulation (modified Seldinger). Wire advancement through catheter.

Puncture the skin over the radial artery with the catheter and needle at an angle of 30-45° to the skin with the needle bevel facing up (see the image below).

Radial artery cannulation (modified Seldinger). An Radial artery cannulation (modified Seldinger). Angle of introduction of radial artery catheter.

Advance the needle until a flash of blood is seen in the needle hub; this initial flash is obtained when the needle tip, which protrudes beyond the end of the catheter, has entered the vessel lumen (see the images below).

Radial artery cannulation (modified Seldinger). Fl Radial artery cannulation (modified Seldinger). Flashback of blood into radial artery catheter hub.
Radial artery cannulation (modified Seldinger). Ra Radial artery cannulation (modified Seldinger). Radial artery catheter entering artery.

Stabilize the needle, and carefully advance the guide wire into the artery by moving the actuating lever as far forward as possible (see the images below). If any resistance to advancing the guide wire is encountered, stop advancing the wire, remove the entire unit, and attempt another puncture. Do not try to retract the guide wire; doing so may shear the tip of the wire.

Radial artery cannulation (modified Seldinger). Ad Radial artery cannulation (modified Seldinger). Advancement of guide wire into radial artery.
Radial artery cannulation (modified Seldinger). Ad Radial artery cannulation (modified Seldinger). Advancement of guide wire into radial artery.

When the guide wire is in place, grasp the hub of the catheter, and advance the catheter over the needle and wire and into the vessel. If difficulty is encountered in passing the catheter, advance the needle 1-2 mm, and reattempt catheter placement. Once the catheter has been advanced, hold the catheter hub in place, and withdraw the needle and guide wire as a single unit (see the image below).

Radial artery cannulation (modified Seldinger). St Radial artery cannulation (modified Seldinger). Stabilization of catheter while introducer is removed.

Confirm that the catheter remains properly positioned in the vessel lumen by monitoring for return of blood at the hub. Blood should flow freely from the end of the catheter hub after the needle and guide wire are removed (see the image below). Attach the catheter to appropriate arterial line tubing, connectors, and transducers. Secure it in place with sutures, tape, or occlusive dressing. (See the images below.)

Radial artery cannulation (modified Seldinger). St Radial artery cannulation (modified Seldinger). Stabilization of catheter while introducer is removed.
Radial artery cannulation (modified Seldinger). Pr Radial artery cannulation (modified Seldinger). Pressure transducer attached to radial artery catheter.
Radial artery cannulation (modified Seldinger). Ra Radial artery cannulation (modified Seldinger). Radial artery cannula sutured in place.
Radial artery cannulation (modified Seldinger). St Radial artery cannulation (modified Seldinger). Sterile dressing applied over radial artery cannula.
Radial artery cannulation (modified Seldinger). In Radial artery cannulation (modified Seldinger). Inline 3-way stop-cocks attached for blood sampling.

Combination Technique

If a longer catheter is needed, first gain access with the catheter-over-needle technique (see Catheter-Over-Needle Technique), and then use the Seldinger technique to replace the shorter catheter with a longer one.

To perform this combination technique, place a wire through the shorter catheter after placement and remove the shorter catheter while holding the wire in place (see the image below).

Femoral artery cannulation (combination technique) Femoral artery cannulation (combination technique). Insertion of guide wire through catheter into femoral artery lumen.

Next, advance the longer (eg, 5-in. [12.7-cm]) catheter, and remove the guide wire once the longer catheter is in place (see the image below). Once proper positioning of the 5-in. catheter within the arterial lumen is confirmed, remove the guide wire. Confirm placement with free-flowing blood, then attach the appropriate tubing and cover with a sterile dressing.

Femoral artery cannulation (combination technique) Femoral artery cannulation (combination technique). Final placement of 20-gauge, 5-in. catheter into femoral artery (note yellow plastic spring wire insertion adapter).

Complications

Common complications of arterial line placement are as follows[2, 31, 32] :

  • Temporary radial artery occlusion (19.7%)
  • Hematoma/bleeding (14.4%)

Less common and rare complications include the following[2, 31, 32] :

  • Localized catheter-site infection (0.72%)
  • Hemorrhage (0.53%)
  • Hematoma (14% radial, 6% femoral) [32]
  • Sepsis (0.13%) [33]
  • Permanent ischemic damage
  • Pseudoaneurysm formation (0.09%) [34]
  • Permanent occlusion (0.09%)
  • Arteriovenous fistula
  • Paralysis of median nerve [35]
  • Femoral artery dissection
  • Suppurative thromboarteritis

A 2014 meta-analysis by O'Horo et al suggested that arterial catheters may be an insufficiently recognized cause of catheter-related bloodstream infection (CRBSI).[33]  The risk of arterial CRBSI was found to be higher with the femoral site than with the radial site. In some cases, complications of indwelling catheters (eg, in the radial artery) may necessitate open surgical intervention for management.[36]

Overall, the more serious complications of arterial line placement are exceedingly rare when correct procedural techniques are used.[37]

 

Medication

Medication Summary

The goal of pharmacotherapy is to provide local anesthesia, both superficial and deep, before and throughout the procedure.

Antiseptics

Class Summary

These agents inhibit growth of gram-positive and gram-negative bacteria.

Chlorhexidine gluconate (PerioGard, Peridex, Hibiclens, Avagard)

Chlorhexidine binds to negatively charged bacterial cell walls and extramicrobial complexes. It has bacteriostatic and bactericidal effects.

Povidone-iodine ophthalmic solution 5% (Betadine)

Povidone-iodine is an antibacterial agent with broad antibacterial and antiviral activity. No bacteria are known to be resistant to it.

Local Anesthetics

Class Summary

Local anesthetic agents are used to increase patient comfort during the procedure.

Lidocaine (Xylocaine)

Lidocaine is an amide local anesthetic. This agent inhibits depolarization of type C sensory neurons by blocking sodium channels. It is provided by means of local infiltration of 1% lidocaine buffered with sodium bicarbonate.

 

Questions & Answers

Overview

What is arterial line placement?

When is arterial line placement indicated?

What are the contraindications for arterial line placement?

What anatomy is relevant to perform arterial line placement?

What are best practices when performing an arterial line placement?

Periprocedural Care

What equipment is needed to perform an arterial line placement?

What equipment is needed to perform a radial arterial line placement?

What equipment is needed to perform a femoral arterial line placement?

What is included in patient preparation for arterial line placement?

How is anesthesia administered for arterial line placement?

How is the patient positioned for arterial line placement?

How is a sterile field created for arterial line placement?

Technique

What is the role of ultrasonography during arterial line placement?

How is the choice of arterial line placement method determined?

What is the role of the Allen test prior to arterial line placement?

How is the catheter-over-needle technique for arterial line placement performed?

What is the catheter-over-wire technique for arterial line placement?

What is the Seldinger technique for arterial line placement performed?

How is the modified Seldinger technique for arterial line placement performed?

How is the combined catheter-over-needle and Seldinger technique for arterial line placement performed?

What are the possible complications of arterial line placement?

Medications

What is the role of medications in the treatment of arterial line placement?

Which medications in the drug class Local Anesthetics are used in the treatment of Arterial Line Placement?

Which medications in the drug class Antiseptics are used in the treatment of Arterial Line Placement?