US ST Case 15 – Poor signal quality
Summary
A 38 year old G8 P7 Gest. week 40+3 admitted to the hospital in spontaneous labor contracting since early in the morning. Unremarkable pregnancy. SVE: Cx 6 cm dilated, 100% effaced, vx -1.
- 16:40 Green Zone tracing noted on admission.
- 18:18 AROM performed with thin meconium stained fluid noted. FSE applied and ST Analysis initiated. SVE: Cx 10 cm, 100% effaced, vx+2.
- 18:30 Active pushing started.
- 18:45 Spontaneous vaginal delivery. Apgar Score 9/10/10.
Cord gases
|
pH |
BE |
|
| Artery |
7.35 |
-2.1 |
| Vein |
7.39 |
-1.8 |
Comment
This is a case with an atypical fECG waveform and poor signal quality throughout the tracing. The T/QRS baseline is never determined; therefore, ST Analysis cannot be used to assess the fetal state. The TOCO transducer is not applied properly, labor progresses very quickly and the patient delivers after only a few pushes.
Reminder
- Check for normal ECG waveform with sufficient signal quality.
- Check for message indicating that baseline T/QRS is determined.
- Gaps in the T/QRS ratios of more than 4 minutes may result in missed ST Events.