Question

A 1-week-old, 4-kg neonate born full term to the operating room for duodenal atresia repair. Preoperative hematocrit is 38%. At the end of the you estimate an intraoperative blood loss of 75 mL. 139 Assuming maintenance of euvolemia, what is the likely postoperative hematocrit?

A. 34%
B. 30%
C. 26%
D. 22%
E. 18%

Answer 1

The estimated postoperative hematocrit for the 1-week-old neonate with a preoperative hematocrit of 38% and an intraoperative blood loss of 75 mL is approximately 30% after adjusting for the blood loss based on the neonate's blood volume.

Step-by-step explanation:

To calculate the estimated postoperative hematocrit after a neonate undergoes duodenal atresia repair with an estimated intraoperative blood loss of 75 mL, we need to take the preoperative hematocrit and adjust it based on the volume of blood lost. A neonate with a preoperative hematocrit of 38% and a weight of 4 kg will have an estimated blood volume of approximately 80-85 mL/kg, which translates to 320-340 mL total. To find the hematocrit after the blood loss, we can use the formula:

Postoperative hematocrit = Preoperative hematocrit \( \times \) (Preoperative blood volume - Blood loss) / Preoperative blood volume

Using the average preoperative blood volume of 330 mL (the midpoint of the estimated range) for calculation:

Postoperative hematocrit = 38% \( \times \) (330 mL - 75 mL) / 330 mL

Postoperative hematocrit = 38% \( \times \) 255 / 330

Postoperative hematocrit = 29.3%

Therefore, the closest answer to the likely postoperative hematocrit is 30% (Option B).