A randomized controlled trial to compare three types of fetal scalp electrode.
OBJECTIVES: To compare three scalp electrodes in respect of need for reapplication, trace quality and scalp trauma. DESIGN: Randomized controlled trial. SETTING: Maternity Unit, Royal Berkshire Hospital, Reading. PARTICIPANTS: 780 women in labour at term, with cephalic fetal presentation, deemed to require electronic fetal heart rate monitoring using a scalp electrode. INTERVENTIONS: Three types of fetal scalp electrode: Rocket-Rolon (double-helix spiral); Hewlett-Packard (double-helix spiral); and Surgicraft-Copeland (clip). MAIN OUTCOME MEASURES: Need for more than one electrode; reason for replacement; trace quality; scalp trauma; direct financial costs. RESULTS: Reapplication was significantly least likely in the Surgicraft-Copeland group (odds ratio vs Hewlett-Packard = 0.61, 95% CI 0.41-0.90; odds ratio vs Rocket-Rolon = 0.43, 95% CI = 0.29-0.62). This reflected a much lower rate of replacement because of detachment. The Hewlett-Packard was, however, least likely to be replaced because of poor trace quality. Interpretable traces were equally common, but trace quality tended to be superior in the Hewlett-Packard group. There was no serious scalp trauma. Difficulty removing the electrode was least often reported in the Hewlett-Packard group, and a mark on the scalp persisted least often in the Rocket-Rolon group. CONCLUSIONS: The Surgicraft-Copeland performed the best overall, and particularly in respect of attachment to the scalp. It appears to be the electrode of choice of the three tested.