Where should the negative (white) lead be placed when applying ECG electrodes?

When applying ECG electrodes, the placement of the negative (white) lead is crucial for accurate monitoring of heart electrical activity. The standard practice is to place the negative lead on the right arm. This positioning is important because it serves as the reference point from which other electrodes can capture the heart's electrical signals in relation to this baseline.

The right arm provides a clear signal that helps to define the electrical axis of the heart and is part of the traditional 12-lead ECG configuration. This standard placement aids in correctly interpreting the electrical conduction pathways and any abnormalities that may be present.

Correct placement of the electrodes also ensures consistency in recordings across different patients and situations, which is vital for accurate diagnosis. The other placements do not align with the conventional setup used for diagnostic purposes, thus they would not provide the optimal reference for the ECG tracing.