Pathophysiological framing of cardiotocographic tracing and Uterine Tachysystole: Research Article

Felis S

doi:10.58372/2835-6276.1084

Authors

Felis S

DOI:

https://doi.org/10.58372/2835-6276.1084

Keywords:

Cardiotocography, Electronic fetal monitoring, Uterine Contraction, Uterine Tachysystole

Abstract

Continuous electronic fetal monitoring (EFM) was first introduced commercially over 50 years ago with the hope of improving perinatal outcomes during labor. However, despite the increased use of EFM, definitive improvements in perinatal outcomes have not been demonstrated. Variance in tracing interpretation and intervention has led to increased rates of cesarean and operative vaginal deliveries and perhaps increased maternal and neonatal morbidity. Since its inception, several strategies have been developed in hopes of optimizing EFM and improving these outcomes.

Tachysystole is defined as more than five contractions in 10 minutes, averaged over 30 minutes. The presence or absence of associated FHR abnormalities is the key issue in management. For women with spontaneous labor, tachysystole coupled with recurrent FHR decelerations requires evaluation and treatment. Tachysystole occurring with less frequent FHR abnormalities may or may not require treatment, depending on the specific clinical situation and associated FHR characteristics such as variability and accelerations. In laboring women receiving oxytocin, management of tachysystole generally involves efforts to reduce uterine activity to minimize risk of evolving fetal hypoxemia or acidemia. In labor induction or augmentation or both, a decrease in the oxytocin dose should be considered if tachysystole occurs in the presence of a Category I tracing. If there is a Category II or III tracing, oxytocin should be reduced or stopped in addition to intrauterine resuscitation. In addition, simultaneous initiation of multiple resuscitative measures may improve fetal condition more rapidly than the use of individual therapies (Table 2). If tachysystole induced FHR abnormalities do not resolve with these initial maneuvers, then tocolytic medications (eg, terbutaline) may be warranted.

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