FDA reviews continue on new fetal monitor. (Designed to Help Detect Fetal Hypoxia).

SEA ISLAND, GA. -- A "very promising" new system for electronic fetal monitoring could provide significant help to clinicians struggling to care for high-risk pregnancies, Dr. Lawrence Devoe said at an ob.gyn. meeting sponsored by the Medical College of Georgia.

The STAN S 21 system combines cardiotocography with automatic ST-waveform analysis. The device was shown in a large randomized clinical trial conducted in Sweden to improve outcomes by increasing clinicians' ability to identify fetal hypoxia and intervene rapidly, said Dr. Devoe, a consultant for Neoventa, the Swedish manufacturer of the system.

But because U.S. studies have not been done on the device, the Food and Drug Administration's Obstetrics and Gynecology Devices panel did not recommend its approval, citing differences in Swedish and American obstetrics practices.

The FDA review is continuing, however, following resolution of most issues of concern. The sole remaining hurdle faced by Neoventa is to conduct a validation study of approximately 6 weeks' duration in the United States. The study is expected to take place this year, according to a company spokesperson.

The need for improved monitoring systems is clear in that currently available monitoring methods all have their shortcomings. Auscultation is impractical and requires one-to-one nursing, said Dr. Devoe, Brooks Professor and chairman, department of obstetrics and gynecology and director of maternal-fetal medicine at the Medical College of Georgia, Augusta.

Auscultation also is not being widely taught, he added. The use of fetal heart rate tracings to detect metabolic acidosis has been plagued with difficulties such as intraobserver variances and lack of standardization of visual criteria, he said.

Efforts have been made to correct these shortcomings, and computerized processing of the heart rate tracings can improve the accuracy and reliability of this modality. But there has been no randomized clinical trial of sufficient size to definitively ...