Application of a Proposed Algorithm to Cesarean Deliveries for Nonreassuring Fetal Heart Rate Tracing

Abstract

Objectives The aim of the study is to evaluate how current management of Category II fetal heart rate tracings compares with that suggested by a published algorithm and whether these differences lead to disparate neonatal outcomes.

Study Design This is a retrospective observational study from the resident service at an academic-community tertiary care center from 2013 to 2018. We reviewed archived fetal heart rate tracings from patients with cesarean delivery performed for nonreassuring fetal heart rate tracing and interpreted tracings against the algorithm. We assigned tracings to one of three categories: Group A—consistent; Group B—inconsistent too early (algorithm permits the patient to labor longer); Group C—inconsistent too late (algorithm suggests performing the cesarean delivery sooner). Maternal demographics, features of labor, and neonatal outcomes were compared.

Results Of the 110 cases, 27 (24.5%) had a cesarean delivery performed in group A, 49 (44.5%) in group B, and 34 (30.9%) in group C. Baseline characteristics were similar. Of the 49 in group B, 46 (93.9%) violated the algorithm at the same branchpoint. In group C, cesarean deliveries would have been performed on average 244 minutes earlier had the algorithm been used. Neonatal outcomes were not significantly different among the groups, including 5-minute Apgar <7, pH <7.1, and NICU admit.

Conclusion Our retrospective application of the algorithm showed that 44.5% of patients who have cesarean delivery for nonreassuring fetal heart rate tracing may be able to labor longer and that violation at a common decision point on the algorithm (moderate variability or accelerations, but a lack of recurrent decelerations) is responsible for nearly all such cesarean deliveries. More studies are needed to evaluate if cesarean delivery rates for nonreassuring fetal heart rate tracing can be reduced without impacting neonatal outcomes using the algorithm.

Key Points

• There is a potential to further standardize management of Category II fetal heart rate tracings.

• In our practice, 25% of cesareans performed for fetal distress were consistent with the algorithm.

• A subset of patients (45%) with cesarean for fetal distress may have been able to labor longer.

Keywords

nonreassuring fetal heart rate tracing - Category II fetal heart rate tracing - cesarean delivery - intrapartum fetal heart rate - acidosis - fetal distress

Note

This project was presented as a poster at The Society for Maternal Fetal Medicine's 40^th Annual Pregnancy Meeting in Grapevine, Texas on February 3 to 8, 2020 (Abstract #1086).

Publication History

Received: 25 October 2020

Accepted: 06 October 2021

Article published online:
28 November 2021

• References

• 1 Barber EL, Lundsberg LS, Belanger K, Pettker CM, Funai EF, Illuzzi JL. Indications contributing to the increasing cesarean delivery rate. Obstet Gynecol 2011; 118 (01) 29-38
• 2 Macones GA, Hankins GD, Spong CY, Hauth J, Moore T. The 2008 National Institute of Child Health and Human Development workshop report on electronic fetal monitoring: update on definitions, interpretation, and research guidelines. Obstet Gynecol 2008; 112 (03) 661-666
• 3 Intrapartum fetal heart rate monitoring: nomenclature, interpretation, and general management principles. ACOG Practice Bulletin No. 106. American College of Obstetricians and Gynecologists. Obstet Gynecol 2009; 114: 192-202
• 4 Clark SL, Nageotte MP, Garite TJ. et al. Intrapartum management of category II fetal heart rate tracings: towards standardization of care. Am J Obstet Gynecol 2013; 209 (02) 89-97
• 5 Clark SL, Hamilton EF, Garite TJ, Timmins A, Warrick PA, Smith S. The limits of electronic fetal heart rate monitoring in the prevention of neonatal metabolic acidemia. Am J Obstet Gynecol 2017; 216 (02) 163.e1-163.e6
• 6 ACOG/SMFM Obstetric Care Consensus. Obstetric care consensus no. 1: safe prevention of the primary cesarean delivery. Obstet Gynecol 2014; 123 (03) 693-711
• 7 Parer JT, Ikeda T. A framework for standardized management of intrapartum fetal heart rate patterns. Am J Obstet Gynecol 2007; 197 (01) 26.e1-26.e6
• 8 International Federation of Gynecology and Obstetrics workshop on the guidelines for the use of fetal heart rate monitoring. Int J Gynaecol Obstet 1987; 25: 159-167
• 9 National Institute of Child Health and Human Development Research Planning Workshop. Electronic fetal heart rate monitoring: research guidelines for interpretation. Am J Obstet Gynecol 1997; 177: 1385-1390
• 10 Van Naarden Braun K, Doernberg N, Schieve L, Christensen D, Goodman A, Yeargin-Allsopp M. Birth prevalence of cerebral palsy: a population-based study. Pediatrics 2016; 137 (01) e20152872
• 11 Cahill AG, Tuuli MG, Stout MJ, López JD, Macones GA. A prospective cohort study of fetal heart rate monitoring: deceleration area is predictive of fetal acidemia. Am J Obstet Gynecol 2018; 218 (05) 523.e1-523.e12
• 12 Shields LE, Wiesner S, Klein C, Pelletreau B, Hedriana HL. A standardized approach for category II fetal heart rate with significant decelerations: maternal and neonatal outcomes. Am J Perinatol 2018; 35 (14) 1405-1410