Chapter 3 - A fibreoptic pressure transducer for intrauterine monitoring

Abstract

This chapter discusses the application of fiberoptic pressure transducer for intrauterine monitoring. The monitoring of the fetal heart rate and of uterine contractions is essential in the active management of labor. Each uterine contraction represents a stress for the fetus, resulting in changes in the fetal heart rate. The importance of the relationship between the fetal heart rate patterns and uterine activity is well established. Until now, intrauterine pressure measurements have been made using either a fluid-filled open-ended catheter coupled to an external pressure transducer or a microelectronic intra-amniotic catheter-tip pressure transducer. Intrauterine pressure measurement must not harm either the fetus or the mother. Fluid-filled open-ended catheters have been shown to be safe because they are soft and flexible, giving way to any resistance. The fibreoptic catheter is as flexible as the open-ended catheter, and the transducer dome is smooth and round so it should be as safe in use as the fluid-filled open-ended catheter technique. As far as electrical safety is concerned, the fiberoptic pressure transducer offers complete galvanic insulation of the patient, because it is made entirely from nonconductive materials.