perinatal-times_2013-03_print_and_read - SSM Cardinal Glennon ...

MONITOR CORNERA CASE STUDY BY SHARON RECTOR, RNC-OB, C-EFM, MSNPRESENTATIONMs. L is a 20 year old, G3P1011 who presented to labor anddelivery at 39 weeks and 3 days gestation with a spontaneouslyruptured bow of water, leaking green tinged amniotic fluid.Contractions on admission were mild and irregular occurringabout every 4-8 minutes. The fetal heart rate (FHR) baselinewas 140 bpm, with moderate variability, accelerationspresent and no decelerations (Category I). Her cervical examon admission was 2 cm, 50% effaced, -3 station, moderateconsistency and midposition with a cephalic presentation. Shewas admitted for expectant management of labor.BACKGROUNDMs. L was previously diagnosed with Bipolar II Disorder forwhich she had inconsistently taken her prescribed medications.She had a history of marijuana use with a positive urine drugscreen for marijuana during the pregnancy. She was alsodiagnosed with GBS bacteriuria in the first trimester.Her labor progressed spontaneously, and she received anepidural for pain management. She was given penicillin G 5million units IV followed by 2.5 million units IV every 4 hours.Approximately 1 hour after the epidural was placed strip #1was observed. Her cervical exam was 4 cm, 50% effaced, -2station, soft and midposition. Her blood pressure was 116/62to 120/70 and her heart rate was 62-68 bpm. Strip #2 occurredapproximately 15 minutes later. How would you interpretthese tracings? What interventions are indicated?INTERPRETATION AND DISCUSSIONIn strip #1 the baseline FHR is 145 bpm, the variability ismoderate, there are no accelerations and there are latedecelerations (Category II). A late deceleration is defined asa gradual (onset to nadir ≥ 30 seconds) decrease of the FHRfrom the baseline associated with a uterine contraction. Inmost cases the onset, nadir and recovery of the decelerationoccur after the beginning, peak and ending of the contraction,respectively. A late deceleration reflects disruption ofmaternal-fetal oxygen transfer from the environment tothe fetus resulting in transient fetal hypoxemia (Tucker,Miller & Miller, 2009). Interventions that will maximize fetaloxygenation are indicated and might include maternal positionchange, intravenous fluid administration, reduction of uterineactivity and oxygen administration. If the disruption of oxygentransfer is recurrent or sustained, it may progress to the stageof metabolic acidemia. The FHR during the decelerations isirregular, ranging from 80-90 bpm to 150-155 bpm, similarto the appearance of marked variability. Variability is aTRACING 1VOL. 27 NO. 1 | MARCH 2013