med 18

 

c. Double volume ET for removal of bilirubin, antibodies, etc.

2 × infant’s blood volume = 2 × 80 – 120 mL/kg

(Infant’s blood volume in preterm infant ≅100 to

120 mL/kg, in term infant ≅80 to 85 mL/kg)

Exchanges approximately 85% of infant’s blood

volume (Fig. 44.2)

d. Single-volume ET: Exchanges approximately 60% of

infant’s blood volume (Fig. 44.2)

e. Partial ET for correction of severe anemia

Volume (mL) =

Infants blood volume × (Hb desired – Hb initial)

Hb of PRBC – Hb initial

Fig. 44.2. Graph depicting the effectiveness of

exchange transfusion against the fraction of blood volume exchanged. The formula permits the calculation of

the final hemoglobin.

318 Section VIII ■ Transfusions

f. Single-volume or partial ET for correction of polycythemia

Volume (mL) =

Infants blood volume × desired HCT change

Initial HCT

4. Preparation of Infant

a. Place infant on warmer with total accessibility and

controlled environment. ET on small preterm

infants may be performed in warm incubators, provided a sterile field can be maintained and lines are

easily accessible.

b. Restrain infant suitably. Sedation and pain relief are

not usually required. Conscious infants may suck on

a pacifier during the procedure.

c. Connect physiologic monitors and establish baseline values (temperature, respiratory and heart rates,

oxygen saturation by pulse oximetry).

d. Empty infant’s stomach.

(1) Do not feed for 4 hours prior to procedure, if

possible.

(2) Place orogastric tube, remove gastric contents,

and leave on open drainage.

e. Start peripheral IV line for glucose and medication

infusion.

(1) If exchange procedure interrupts previous essential infusion rate

(2) If prolonged lack of enteral feeds or parenteral

glucose will lead to hypoglycemia

(3) Extra IV line may be necessary for emergency

medications.

f. Stabilize infant prior to starting exchange procedure

(e.g., give packed-cell transfusion when severe hypovolemia and anemia are present); modify ventilator

or ambient oxygen as required.

g. The use of albumin infusions prior to ET to improve

bilirubin binding remains controversial (27).

3. Establish Access for ET

a. Push–pull technique: Central access—usually

through umbilical venous catheter (UVC).

b. Isovolumetric exchange with simultaneous infusion of donor blood through venous line and

removal of baby’s blood through arterial line. This

technique may be better tolerated in sick or unstable neonates because there is less fluctuation of

blood pressure and cerebral hemodynamics (28).

The technique is also favored when only peripheral vascular access is available or it is preferred for

various reasons (29,30).

(1) Infusion of donor blood may be through UVC

or peripheral IV catheter.

(2) Removal of baby’s blood may be from umbilical

arterial or venous catheter, or peripheral arterial

catheter, usually a radial arterial line.

4. Laboratory Tests on Infants Blood Pre-exchange

Tests are based on clinical indications.

a. Pre-exchange diagnostic studies. Note that diagnostic serological tests on the infant, such as studies to

evaluate unexplained hemolysis, antiviral antibody

titers, neonatal metabolic screening, or genetic tests

should be drawn prior to the ET.

b. Hemoglobin, hematocrit, platelets

c. Electrolytes, calcium, blood gas

d. Glucose

e. Bilirubin

f. Coagulation profile

5. Prepare Blood