33.4d ECG Graph Paper

ECG graph paper

(?) is standardized to allow comparative analysis of ECG patterns.

25 mm/second

The paper moves across the stylus at a standard speed of (?) (Figure 33-18).

amplitude

The (?) of the ECG deflection is also standardized.

two large boxes

When properly calibrated, the ECG stylus should deflect (?) when 1 mV is present.

calibration buttons

Most machines have (?) , and a calibration curve should be placed at the beginning of the first ECG strip.

automatically

Many machines do this (?) when they are first turned on.

grid of light and heavy lines

The ECG graph is divided into a (?).

1 mm

The light lines are (?) apart, and the heavy lines are 5 mm apart.

5 mm

The light lines are 1 mm apart, and the heavy lines are (?) apart.

large squares

The heavy lines thus enclose (?) , each containing 25 of the smaller squares formed by the lighter lines (Figure 33-19).

horizontal axis

The following relationships apply to the (?).

1 small box = 0.04 sec.

(?).

1 large box = 0.20 sec.

(?).

duration of the ECG complexes and time intervals

These increments measure the (?) .

vertical axis

The (?) reflects the voltage amplitude in millivolts (mV).

Two large boxes equal 1 mV.

(?).

time interval markings

In addition to the grid, ECG paper has (?) at the top.

3-second intervals

These marks are placed at (?).

15 large boxes

Each 3-second interval contains (?).

heart rate

The time markings measure (?).