Chapter Four Key Terms

Midclavicular line

An imaginary line on the chest that runs vertically through the center of the clavicle

Anterior axillary line

An imaginary vertical line starting at the front axilla (armpit) that extends down the left side of the chest.

Midaxillary Line

An imaginary vertical line that starts at the middle of the axilla (armpit) and extends down the side of the chest.

Intercostal space (ICS)

The space between two ribs

Suprasternal notch

The dip you feel at the anterior base of the neck just above the manubrium where the clavicle attaches to the sternum.

Angle of Louis

A ridge about an inch or so below the suprasternal notch where the main part of the sternum and the top of the sternum, known as the manubrium, are attached.

Somatic tremor

Voluntary or involuntary muscle movement; also known as body tremor.

Wandering Baseline

Artifact in which the tracing drifts away from the center of the graph paper. Also known as baseline shift.

Alternating current (AC) interference

Unwanted markings on the ECG caused by other electrical current sources.

Interrupted baseline

When one or more leads appear as a flat line on the ECG tracing. Usually caused by loose or unplugged leads.

Dextrocardia

When the heart is on the opposite or right side of the chest.

Posterior axillary line

Imaginary line on the back that runs vertically from the shoulder down on the outer edge of the rib cage

Midscapular line

Imaginary line on the back that runs vertically through the center of the scapula

Paraspinous line

An imaginary line on the spine that runs vertically through the side of the spine.

Seizure

An interruption of the electrical activity in the brain that causes involuntary muscle movement and sometimes unconsciousness