Cord blood gas and pH analysis is done in following circumstances except
**Core Concept**
Cord blood gas analysis is a crucial diagnostic tool in assessing fetal acid-base status and detecting potential complications during delivery. This test measures the pH, pCO2, and pO2 levels in the umbilical cord blood, providing valuable information about fetal well-being.
**Why the Correct Answer is Right**
Cord blood gas analysis is typically performed in situations where there is a concern about fetal distress, such as in cases of prolonged labor, fetal heart rate abnormalities, or umbilical cord prolapse. The analysis helps identify whether the fetus has been exposed to hypoxia or other metabolic derangements during labor. The pH, pCO2, and pO2 values in the cord blood can indicate the presence of acidosis, alkalosis, or other disturbances in the fetal acid-base balance.
**Why Each Wrong Option is Incorrect**
**Option A:** This is a correct indication for cord blood gas analysis. Prolonged labor can lead to fetal distress, making cord blood gas analysis essential in assessing fetal well-being.
**Option C:** Umbilical cord prolapse is another critical situation where cord blood gas analysis is warranted to assess fetal acid-base status and guide immediate management.
**Clinical Pearl / High-Yield Fact**
Cord blood gas analysis should be performed in all cases of suspected fetal distress, regardless of the presence of meconium-stained amniotic fluid. This is because meconium staining can be a sign of fetal distress, but it is not a reliable indicator of fetal acid-base status.
**Correct Answer: D**