82 Section II ■ Physiologic Monitoring

2. Only TSB measurements should be performed in

infants with severe enough jaundice to warrant

exchange transfusion (7).

3. TCB is less accurate in infants undergoing phototherapy; therefore, serum levels are preferred for monitoring bilirubin values in such infants (2,5,11,13).

4. Race/skin color: TCB readings obtained by the

BiliChek have been found to correlate with TSB values

in white, black, Asian, Hispanic, indigenous African,

and Indian infants (7,13,16). In black infants, TCB

readings obtained by the JM-103 correlate less closely

with TSB values, with the TCB generally being greater

than the TSB (6).

F. Techniques

1. Calibrate the TCB device according to manufacturer

specifications. New devices should be correlated with

serum samples before use.

2. Measure TCB by pressing the trigger button and gently

pressing the tip to the infant’s forehead or sternum until

the device indicates that reading is complete.

a. Some studies have shown that TCB measurements

from the sternum correlated slightly better with TSB

levels than TCB measurements from the forehead,

possibly as a result of the exposure of the forehead to

ambient light. Other studies indicate both sites to be

equivalent (6,17).

b. Measurements must be taken in a consistent manner with regard to placement of the probe and

amount of pressure applied to the device.

Interoperative and intraoperative variability may be

minimized with proper training (6).

c. Measurement of the TCB using the BiliChek system takes approximately 20 to 80 seconds. This time

is required for the monitor to make five measurements that are averaged to provide one TCB value.

The JM-103 takes approximately 10 seconds to

obtain its dual measurements and calculate the

TCB value.

3. Repeated use of the disposable probes is not recommended.

G. Complications

No complications have been reported from the use of TCB

monitors, except for the risk of inappropriate use and the

possibility of underestimation of the level of jaundice.

H. Effectiveness

TCB measurement has been shown to decrease the number

of heel pricks in some studies but has not changed the length

of hospital stay or number of newborns requiring phototherapy. TCB monitoring has been shown to reduce the number

of infants readmitted for phototherapy (18).

Fig. 12.6. Measurement principle of the BiliChek Noninvasive

Bilirubin Analyzer. (Reproduced with permission of Children’s

Medical Ventures/Respironics.)

Fig. 12.5. Measurement principle of Konica Minolta/AirShields JM-103 Jaundice Meter. (Reproduced with permission

from J Perinat Med., Vol. 31, Pages 81–88, Copyright © 2003 by

Walter de Gruyter GmbH & Co. KG Berlin, New York.)