A 1.8-kg premature infant is scheduled for an exploratory laparotomy due to a bowel obstruction. The child's last hematocrit was 40%. Which of the following is the MAXIMUM allowable blood loss to have an intraoperative transfusion trigger of 33%?
Maximum allowable blood loss (MABL) can be calculated with the patient's estimated blood volume (EBV), initial hematocrit (Hcti), and postoperative target hematocrit (Hctt) using the following formula:
MABL = (EBV × [Hcti – Hctt]) / Hcti
The accompanying table presents EBV by age group.
Based on this information, the EBV of a 1.8-kg premature neonate would be 180 mL. Substituting this and the initial and target hematocrit values into the equation results in the following:
MABL = (180 × [40 – 33]) / 40 = (180 × 7) / 40 = 31.5...