The circulatory system is a complicated network of veins and arteries that run through every part of the body. Oxygenated blood travels through the arteries, providing cells with the oxygen and nutrients they need to function properly. The brachial artery is the main blood supply to the arm, forearm, hands, and fingers. Because it is close to the surface of the arm, it's easy to locate and doctors use it in a variety of medical assessments and procedures.

Origin: the Axillary Artery

The axillary artery runs through the axilla or armpit and becomes the brachial artery, which starts at the teres major muscle on the underside of the upper arm between the elbow and shoulder and ends at the cubital fossa on the inner elbow. From there, it divides into the ulnar artery and radial artery, which run along the two bones of the forearm.

Upper Arm Elbow mheim3011 / Getty Images


Primary Blood Supply to the Arm

The brachial artery and its branches are the main blood supply for the arm from the axilla to the hand. The vessel feeds the biceps directly, while the triceps and deltoid muscles receive blood from the profunda brachii or deep brachial artery, which branches off, as do the ulnar and radial arteries.

Arm Blood Supply mraoraor / Getty Images


Transporting Oxygenated Blood.

Oxygenated blood leaves the heart and circulates through the body, delivering oxygen and nutrients to the cells. From there, it travels through the veins, back to the right side of the heart, and into the lungs where it is reoxygenated before being pumped back into the body. The brachial artery is responsible for supplying all the cells in the arm with the oxygen and nutrients they need.

Artery Blood Circulation magicmine / Getty Images


Arm Injuries and the Brachial Artery

The brachial artery is close to the surface and lays so close to the humerus in the upper arm and the elbow that there is a significant risk for damage when a person endures a fracture or other trauma. Healthcare professionals take great care when assessing these injuries to make sure there is no damage to the vessel.

Upper Arm Injury fotofreaks / Getty Images


Brachial Artery Variations

Most people have typical brachial arteries, but there are some exceptions. About 20 percent of the population has completely or partially duplicated brachial arteries. Another possible difference is a superficial brachial artery that runs anteriorly to the median nerve in the upper arm, instead of behind it.

Anatomy Variations Brachial Artery Staras / Getty Images


Use in Dialysis

Some surgical procedures involve creating a fistula, which establishes a direct connection between an artery and a vein to prepare for hemodialysis. This treatment for people with kidney disease filters impurities out of the blood when the kidneys do not work properly. The fistula is usually formed between the brachial artery and vein to create an access point for the artificial kidney or dialysis machine.

Dialysis Machine Fistula Jupiterimages / Getty Images


Brachial Artery and Blood Draws

Technicians and nurses always take common lab draws from a vein, not an artery. When a tourniquet is applied to the upper arm, blood backs up into the vein, making it easier to feel. One exception is an arterial blood gas, a special blood test typically only performed in hospitals, by a doctor, on patients with critical heart or lung problems. It measures oxygen and other values that indicate how well the blood is oxygenating.

Arterial Blood Gas jarun011 / Getty Images


Measuring Blood Pressure

Because the brachial artery is close to the surface, healthcare providers use it to assess blood pressure. The cuff goes around the upper arm and is inflated while the bell of a stethoscope sits directly on the brachial artery. The practitioner determines the reading by listening for a knocking sound while looking at the sphygmomanometer.

sphygmomanometer blood pressure CasarsaGuru / Getty Images


Pressure Differences Between Arteries

Medical practitioners expect a small difference in blood pressure between one arm and the other, but any reading with a difference of more than ten can signal trouble. For people who consistently register different readings, this could indicate a blocked artery, diabetes, vascular disease, kidney disease, or even a heart defect.

Difference Blood Pressure PeopleImages / Getty Images


Checking the Pulse in Infants

Medical professionals commonly check the pulse of adults with the carotid artery in the neck. Infants have very short necks, which can make the carotid pulse difficult to locate, so many doctors use the brachial artery instead. This method is taught to healthcare professionals receiving advanced cardiac life support certification as well as in basic CPR classes.

Infant Pulse Assessment Squaredpixels / Getty Images


Popular Now on Facty Health


This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.