Where should lead V5 be placed on a patient?

Lead V5 should be placed on the mid-clavicular line at the 5th intercostal space. This placement is critical for accurate electrocardiogram (ECG) readings, as V5 is specifically used to assess the lateral wall of the heart.

The mid-clavicular line is an anatomical reference running down from the midpoint of the clavicle, providing a consistent point for electrode placement. The 5th intercostal space is located between the 5th and 6th ribs, usually found approximately at the level of the apex of the heart. Proper placement in this location ensures that the electrical activity recorded by the V5 lead accurately reflects the heart's lateral activity, which is essential for diagnosing conditions related to heart health, such as ischemia or infarction in the left lateral wall.

Other placements mentioned, while they may correlate with different leads (such as limb leads or other precordial leads), do not correspond to V5 specifically and would not provide the necessary information to assess the lateral aspects of heart function. Therefore, the placement at the mid-clavicular line and 5th intercostal space is the standard for V5 and is crucial for effective monitoring and assessment of cardiac health.