The brachial pulse is the preferred location for quickly assessing an infant’s heart rate. This artery is a major vessel carrying oxygenated blood down the arm, making its pulse detectable even when circulation is compromised. Unlike adults, who use the radial pulse at the wrist or the carotid pulse in the neck, an infant’s smaller size makes these sites unreliable. The infant’s short neck makes the carotid artery hard to locate, and the radial pulse may be too faint, especially in emergencies.
Identifying the Brachial Pulse Site
The brachial pulse is located on the inner aspect of the infant’s upper arm. To find the correct spot, you must look for the artery running between the shoulder and the elbow joint. Specifically, the artery courses deep within the groove formed by the biceps and triceps muscles.
The most reliable location is roughly midway along the upper arm, just above the crease of the elbow. At this point, the brachial artery lies close to the humerus bone. This proximity allows the vessel to be compressed against a firm surface for palpation, making the pulse stronger and more consistently felt. The location is along the fleshy part of the inner arm, between the armpit and the elbow crease.
Step-by-Step Procedure for Assessment
To begin the assessment, gently place the infant on their back on a safe, firm surface, and ensure the arm you are checking is slightly extended and relaxed. The inside of the arm should be exposed and facing upward to allow for easy access to the artery.
Use the tips of your index and middle fingers to palpate the designated area on the inner upper arm. It is important to avoid using your thumb, as the thumb has its own strong pulse which could lead to an inaccurate reading. Apply a light, but firm, downward pressure to compress the artery against the underlying bone. Excessive pressure should be avoided, as it can completely occlude the artery and make the pulse undetectable.
Once you feel the rhythmic throbbing, you can begin counting the beats to determine the heart rate. A common technique for routine assessment is to count the beats felt over a 15-second interval and then multiply that number by four to calculate the beats per minute. For an emergency assessment, the pulse should be checked for no more than 10 seconds before proceeding with intervention.
Context for Checking an Infant’s Pulse
The brachial pulse is most often checked during two primary scenarios: routine physical examinations and emergency assessments. Assessing the pulse helps determine the overall function of the circulatory system. Resting heart rates for infants vary by age, falling in the range of 80 to 160 beats per minute for infants 1 to 11 months old, and slightly higher for newborns.
In an emergency, such as when an infant is unresponsive or not breathing, the brachial pulse check is a rapid way to determine if the heart is still circulating blood effectively. The brachial artery is one of the last peripheral pulses to become undetectable, meaning its presence offers a reliable sign of continued circulation.
If the pulse is absent, or if the heart rate is below 60 beats per minute and the infant shows signs of poor perfusion, immediate action is required. Signs of poor perfusion include pale or bluish discoloration of the skin and extremities. In these circumstances, the standard protocol is to begin cardiopulmonary resuscitation, starting with chest compressions.