Which fetal heart rate pattern indicates abnormal acid-base status?

Category III fetal heart rate patterns are indicative of abnormal acid-base status and require immediate clinical intervention. This category is characterized by specific patterns such as repeated variable decelerations, prolonged decelerations, or a sinusoidal pattern. These findings suggest that the fetus may be experiencing stress and inadequate oxygenation, leading to potential fetal hypoxia or acidosis.

Recognizing Category III patterns is essential for effective clinical decision-making, as they signal the need for close monitoring and possibly urgent delivery, depending on the overall clinical situation. In contrast, Category I patterns are reassuring and not associated with fetal distress, while Category II patterns may require further observation but do not indicate urgent intervention. Baseline variability refers to the normal fluctuations in the fetal heart rate over time, and while it helps in assessing fetal well-being, it does not itself determine the acid-base status.