An arterial line (also art-line or a-line) is a thin

catheter In medicine, a catheter ( ) is a thin tubing (material), tube made from medical grade materials serving a broad range of functions. Catheters are medical devices that can be inserted in the body to treat diseases or perform a surgical procedure. ...

inserted into an

artery An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in ...

Use

Arterial lines are most commonly used in

intensive care medicine Intensive care medicine, usually called critical care medicine, is a medical specialty that deals with seriously or critically ill patients who have, are at risk of, or are recovering from conditions that may be life-threatening. It includes p ...

and

anesthesia Anesthesia (American English) or anaesthesia (British English) is a state of controlled, temporary loss of sensation or awareness that is induced for medical or veterinary purposes. It may include some or all of analgesia (relief from or prev ...

to monitor

blood pressure Blood pressure (BP) is the pressure of Circulatory system, circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term ...

directly and in real-time (rather than by intermittent and indirect measurement) and to obtain samples for

arterial blood gas An arterial blood gas (ABG) test, or arterial blood gas analysis (ABGA) measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood be drawn from the radial artery with a syringe an ...

analysis. Arterial lines are generally not used to administer medication, since many injectable drugs may lead to serious tissue damage and even require amputation of the limb if administered into an

rather than a vein. An arterial line is usually inserted into the

radial artery In human anatomy, the radial artery is the main artery of the lateral aspect of the forearm. Structure The radial artery arises from the bifurcation of the brachial artery in the antecubital fossa. It runs distally on the anterior part of the ...

in the wrist, but can also be inserted into the

brachial artery The brachial artery is the major blood vessel of the (upper) arm. It is the continuation of the axillary artery beyond the lower margin of teres major muscle. It continues down the ventral surface of the arm until it reaches the cubital fossa ...

at the elbow, into the

femoral artery The femoral artery is a large artery in the thigh and the main arterial supply to the thigh and leg. The femoral artery gives off the deep femoral artery and descends along the anteromedial part of the thigh in the femoral triangle. It enters ...

in the groin, into the

dorsalis pedis artery In human anatomy, the dorsalis pedis artery (dorsal artery of foot) is a blood vessel of the lower limb. It arises from the anterior tibial artery, and ends at the first intermetatarsal space (as the first dorsal metatarsal artery and the deep pla ...

in the foot, or into the

ulnar artery The ulnar artery is the main blood vessel, with oxygenated blood, of the Human Anatomical Terms#Anatomical directions, medial aspects of the forearm. It arises from the brachial artery and terminates in the superficial palmar arch, which joins ...

in the wrist. A golden rule is that there has to be

collateral circulation Collateral circulation is the alternate Circulatory system, circulation around a blocked blood vessel, artery or vein via another path, such as nearby minor vessels. It may occur via preexisting vascular redundancy (analogous to redundancy (engi ...

to the area affected by the chosen artery, so that peripheral circulation is maintained by another artery even if circulation is disturbed in the cannulated artery. Insertion is often painful; an anesthetic such as

lidocaine Lidocaine, also known as lignocaine and sold under the brand name Xylocaine among others, is a local anesthetic of the amino amide type. It is also used to treat ventricular tachycardia and ventricular fibrillation. When used for local anae ...

can be used to make the insertion more tolerable and to help prevent

vasospasm Vasospasm refers to a condition in which an arterial spasm leads to vasoconstriction. This can lead to tissue ischemia (insufficient blood flow) and tissue death (necrosis). Along with physical resistance, vasospasm is a main cause of ischemi ...

, thereby making insertion of the arterial line somewhat easier. Often times, this is also done after induction of General anesthesia.

References

{{Intensive care medicine Catheters Diagnostic intensive care medicine