return to: Pediatric Otolaryngology
see also: Tonsillectomy and Adenoidectomy; Cleft Lip and Palate Protocols Pediatric Fluid Management
The volume of circulating blood should be estimated prior to taking a newborn to the operating room. Blood volumes constitute a greater percentage of body mass in preterm neonates in comparison to their full term counterparts. The estimated blood volumes may be calculated with the following numbers:
Age | Circulating blood volume |
---|---|
Preterm neonate | 90 -100 |
Full term neonate | 80 - 90 |
Infant | 70 - 80 |
Child | 70- 75 |
Obese child | 60 - 65 |
Adult | 65 - 70 |
This calculation allows us to estimate the maximum allowable blood loss for a procedure. This is calculated from the estimated blood volume, the initial hematocrit and the minimal allowable hematocrit.
In general, a healthy child does not require transfusion unless the hematocrit has fallen to the 20-25 range for an infant, or 20 for a child. In pre-term infants, transfusion should be performed based on clinical evaluation of the patient.
To calculate the maximum allowable blood loss, the following formula is used:
MABL = EBV X (Child's hematocrit - Minimum accepted hematocrit)
Child's hematocrit
Whereas the EBV for a 5 kg infant is: 5 kg x 80 mL/kg = 400 mL
Leaving the equation: MABL = 400 x (36-25) = 122 mL
36
*Of note, a heel stick can be performed at UIHC to obtain a H/H.
REFERENCES:
- Roseff SD, Luban NL, Manno CS: Guidelines for assessing appropriateness of pediatric transfusion. Transfusion. 2002;42(11):1398.
- Strauss RG. How I transfuse red blood cells and platelets to infants with the anemia and thrombocytopenia of prematurity. Transfusion. 2008;48(2):209