Chapter 8 ■ Cardiorespiratory Monitoring 51

6. To avoid skin damage, do not use fingernails to remove

electrodes.

7. Secure the patient cable to the patient’s environment to

prevent excessive traction.

8. Use only monitors that have been checked for safety

and performance—usually indicated by a dated sticker

on the monitor.

9. Do not use monitors with defects such as exposed wires,

broken or dented casing, broken knobs or controls, or

cracked display.

10. Monitor alarms should prompt immediate patient

assessment.

a. Note alarm indication (i.e., tachycardia or bradycardia).

b. Treat patient condition as necessary or correct the

source of any false alarm.

c. If alarm is silenced or deactivated during the course

of patient evaluation, it should be reactivated prior

to leaving the patient’s bedside.

G. Techniques

1. Familiarize yourself with the monitor prior to beginning.

2. Electrode and lead wire placement: Although you

should refer to the monitor manufacturer’s placement

instructions, general electrode placement guidelines

follow.

a. Skin preparation: Skin should be clean and dry to

provide the best electrode-to-skin interface.

(1) Wipe skin with an alcohol pad and allow to dry

thoroughly.

(2) Avoid the use of tape to secure electrodes—for

optimal performance and proper electrical

interface, electrodes must adhere directly to

skin.

b. Basic three-lead configuration for electrode placement (for electrodes with integrated lead wires)

(Fig. 8.3)

(1) Right arm (white): Right lateral chest at level of

the nipple line

(2) Left arm (black): Left lateral chest at level of the

nipple line

(3) Left leg (red or green): Left lower rib cage

(4) Although this configuration allows the use of the

same electrodes to monitor both ECG and respiration, optimal ECG signal may be obtained

when the right arm lead is at the right midclavicle and the left leg lead is at the xiphoid (4).

c. If not using electrodes with integrated wires, place

electrode pads in basic three-lead configuration as

above, then connect lead wires via electrode clips.

(1) White lead (right arm) to right chest electrode

(2) Black lead (left arm) to left chest electrode

(3) Red or green lead (left leg) to left lower rib cage

electrode

3. Turn monitor on—most monitors will conduct an automatic self-test.

4. Connect the patient cable to the monitor.

5. Select the lead that provides the best signal and QRS

size (lead II is usual default) (Fig 8.4).

a. Ensure that heart rate correlates to QRS complexes

seen on display—make sure that the QRS detector is

not counting high or peaked T or P waves.

6. Verify that low and high heart rate alarms are set appropriately.

H. Complications

1. Skin lesions (rare)

a. Irritation from alcohol—may occur with even shortterm application to immature skin

b. Trauma caused by rubbing with excessive vigor during skin preparation

c. Irritation from incorrectly formulated electrode gel

d. Secondary effects of skin breakdown

(1) Cellulitis or abscess formation

(2) Increased transepidermal water losses

(3) Hypo- or hyperpigmented marks at sites of prior

irritation or inflammation (Fig. 8.5)

2. Erroneous readings caused by artifacts (5) (Table 8.1)

a. Electrical interference

(1) Sixty-cycle electrical interference (frequency of

typical power lines)

Fig. 8.3. Basic electrode placement and lead vectors for optimal ECG signal detection. Right arm/left arm positions also provide maximal signal for impedance pneumography.

52 Section II ■ Physiologic Monitoring

(2) Interference from other equipment used in the

patient’s immediate environment

(3) Electrical spike may be generated when certain

types of polyvinyl chloride tubing are mechanically deformed by infusion pump devices—spikes

appear as ectopic beats on the monitor (rare) (6).

b. Decreased signal amplitude with motion artifact

c. Poor electrode contact or dried electrode gel

d. Incorrect vectors because of inaccurate lead placement (Fig. 8.6)

e. Inappropriate sensitivity settings

3. Monitor or cable failure

a. Hardware or software failure

b. Cable disconnection

4. Alarm failure

a. False alarms (either tachycardia or bradycardia)

resulting from inaccurate interpretation of heart rate

b. Inappropriate alarm parameters for patient

Respiratory Monitoring

A. Purpose

1. Reliable and accurate monitoring of neonatal respiratory activity

a. Trending of respiratory activity over time

b. Detection of apnea

2. Assessment and surveillance of critically ill neonates

3. To provide early warning of potentially significant

changes in respiratory rate by identifying respiratory

rates above or below preset alarm limits

B. Background

1. Measurement of transthoracic impedance is the most commonly used method for determining respiratory rate (7).

A low-level, high-frequency signal is passed through

the patient’s chest via surface electrodes.

Fig. 8.4. Typical ECG tracings: Lead I (top), lead II (middle),

and lead III (bottom).

Fig. 8.5. Residual hyperpigmented marks on the extremities

present more than 1 year after application of ECG leads for cardiorespiratory monitoring.

Problem Treatment

Poor electrode contact/

connection

1. Gently clean skin with alcohol wipe and

allow to dry prior to electrode reapplication.

2. Check electrode/cable connections.

Dried electrode Replace

Equipment interference 1. Systematically turn off one piece of adjacent equipment at a time while observing

monitor for improvement in signal quality.

2. After source of interference is identified,

increase distance between that equipment

and patient while rerouting power cords

and cables as necessary.

3. If above maneuver is unsuccessful, replace

equipment.

60-Hz interference 1. Follow procedure for poor electrode

contact.

2. Replace patient cable.

3. If 1 and 2 are unsuccessful, try an alternate

monitor.

Table 8.1 Steps to Minimize Artifact

Interference