Arterial Line Placement

• Continuous blood pressure measurement is necessary because of hemodynamic instability.
• Continuous blood pressure measurement is necessary for the safety of certain anesthetic techniques, such as deliberate hypotension, cardiopulmonary bypass, or major vascular surgery involving arterial clamping.
• Continuous blood pressure measurement is necessary for monitoring administration of vasoactive drugs.
• Frequent blood gas measurements are needed.
• Frequent blood sampling is needed in patients without central venous access.
• Noninvasive blood pressure monitoring is difficult or impossible, such as in patients who are severely obese, have burned extremities, or are in shock.

• Absolute contraindications
• Infection at the site of insertion
• Traumatic injury proximal to the site of insertion
• Relative contraindications; may be outweighed by other considerations
• Failure to demonstrate collateral flow in small vessels (e.g., by Doppler ultrasonography)
• Presence of arteriovenous (AV) shunt in the limb in question
• History of surgery disrupting lymphatics of the upper extremity, such as a mastectomy with lymph node dissection
• Arterial insufficiency in the distribution of the artery to be cannulated

Upper Extremity Arterial Catheterization

• Sterile prep solution, preferably chlorhexidine
• 1% lidocaine solution if patient is awake
• 20- to 22-gauge angiographic catheter and needle
• Arm board
• Sterile dressing
• Tape
• Transduction system for monitoring
• Optional devices: ultrasound, wire

Femoral Artery Catheterization

• Sterile prep solution
• 1% lidocaine solution if patient is awake
• 16- to 20-gauge angiographic catheter and needle
• Wire of small enough gauge to pass through the angiocatheter or needle
• Sterile dressing
• Tape
• Transduction system for monitoring
• Optional devices: ultrasound, suture

• Multiple arteries are available for easy cannulation and transduction.
• Choice of arteries to be cannulated include but are not limited to the radial, brachial, axillary, dorsalis pedis, and femoral arteries.
• The radial artery can be palpated on the distal portion of the forearm between the radius and the tendon of the flexor carpi radialis.
• The brachial artery can be palpated as it courses medial to the biceps muscle and tendon into the antecubital fossa, with the arm extended and the palm facing up.
• The axillary artery may be palpated best in the axillary space, with the arm abducted and externally rotated.
• The femoral artery may be best palpated below the inguinal ligament, midway between the anterior superior spine of the ilium and the symphysis pubis.
• The dorsalis pedis artery may be palpated on the arch of the foot, between the first and second metatarsals.
• Choice of artery is dependent on the ability to palpate a pulse or to locate it by Doppler ultrasonography.
• The published literature does not support a higher infection rate in femoral artery catheters when compared to radial artery catheters.
• Physicians may want to assess the collateral circulation if cannulating the smaller arteries such as the radial or dorsalis pedis arteries.
• Allen’s test is not a reliable way to evaluate collateral circulation.
• In one large series of 1,782 patients, Allen’s test was not found to predict postcannulation complications. In fact, complete radial artery occlusion was found in 25% of patients, without associated ischemic consequences.

• Clearly label the arterial line to prevent misidentification of the line as venous, with subsequent unintentional injection of drugs or other therapeutic substances into a peripheral artery.
• Use sterile technique when injecting saline or connecting tubing to lumens of catheter. **STERILE TECHNIQUE**
• Always aspirate catheter and tubing to clear bubbles before injecting saline, heparin flush, or blood to avoid air embolism.
• Routine dressing changes with use of sterile prep
• Daily exam of insertion site for signs of infection
• Upon catheter removal, maintain pressure at the insertion site for 5 to 15 minutes. In coagulopathic patients, this period may need to be longer.

• Common
• Kinking of the catheter
• Blockage or obstruction of the catheter
• Air embolism
• Hematoma
• Arterial vasospasm during insertion attempts
• Vascular disease making catheter insertion difficult
• Radial artery occlusion; at least one study suggests this may occur in up to 25% of patients, but was not associated with ischemia or other serious sequelae.
• Accidental injection of drugs or other substances intraarterially because of misidentification of the line as an intravenous catheter.
• Infrequent
• Thrombosis can occur in up to 25% of catheters; clinically significant thrombosis rarely occurs (<1%).
• Thrombosis risk can be lowered by infusing the catheter with heparinized saline.
• Neuropathy
• Thromboembolism
• Serious, rare complications
• Infection is rare (<0.5%). Studies do not indicate that infection rates are higher with femoral than with radial artery cannulation.
• Arterial aneurysm, pseudoaneurysm, or arteriovenous fistula formation
• Peripheral ischemia due to arterial occlusion