Fetal Scalp Electrode
The fetal scalp electrode is spiral electrical wire that is covered in a sterile plastic sheath and ends in a prong that connects to the fetal monitoring system in labor rooms. Placement involves attachment of the electrode onto the fetal scalp for direct measurement of fetal heart rate (FHR) by electrical activity. The tip attaches about 2mm onto the scalp skin covering the bony portion of the fetal head. We will cover the topics for FSE listed below.
The FSE works by detecting the R to R interval on the fetal electrocardiogram QRS complex. This is different from external monitoring which uses a Doppler US transducer to detect movement of cardiac structures. It is important that the FSE is only placed after the presenting fetal part is identified and it is not placed over sutures or fontanels. The FSE should not be routinely used in intrapartum fetal monitoring without appropriate indications.
