EFM Fetal Oxygenation and Acid-Base Balance 2

Question 1

Metabolic acidosis in the fetus is primarily caused by:

Accepted Answer

Accumulation of lactic acid from anaerobic metabolism

Answer

Acute hyperventilation by the mother

Answer

Elevated maternal PCO2 levels

Answer

Decreased fetal respiratory rate

Question 2

Compared to umbilical artery blood, umbilical vein blood would normally show:

Accepted Answer

Higher pH and lower PCO2

Answer

Lower pH and higher PCO2

Answer

Same pH and lower PO2

Answer

Lower pH and lower PO2

Question 3

An elevated fetal PCO2 in cord blood gas analysis most directly indicates:

Accepted Answer

Impaired CO2 clearance across the placenta

Answer

Anaerobic metabolism

Answer

Bicarbonate depletion

Answer

Fetal sepsis

Question 4

The normal lactate level in umbilical artery blood is approximately:

Accepted Answer

< 4.8 mmol/L

Answer

< 2 mmol/L

Answer

< 8 mmol/L

Answer

< 12 mmol/L

Question 5

The bicarbonate buffer system in fetal blood primarily serves to:

Accepted Answer

Neutralize excess hydrogen ions produced by anaerobic metabolism

Answer

Transport oxygen to fetal tissues

Answer

Facilitate CO2 transport from fetus to placenta

Answer

Regulate fetal blood glucose levels

Question 6

Base excess (BE) in fetal cord blood is negative (base deficit) when:

Accepted Answer

Bicarbonate stores have been consumed by buffering excess acid

Answer

Respiratory alkalosis is present

Answer

Metabolic alkalosis is present

Answer

PCO2 is elevated above normal

Question 7

Mixed acidosis in fetal cord blood gas analysis is characterized by:

Accepted Answer

Low pH, elevated PCO2, and elevated base deficit

Answer

Low pH, normal PCO2, and normal base deficit

Answer

Normal pH with elevated PCO2 only

Answer

Low pH with normal bicarbonate and normal PCO2