Cardiotocography and ST analysis (STAN): a retrospective review

Fetal heart monitoring via cardiotocograph (CTG) has become integral to modern maternity care. The development of more sophisticated analytical techniques for fetal heart rate analysis has resulted in fetal monitoring systems that can add automated fetal electrocardiographic ST segment analysis (STAN) to the customary CTG information, providing continuous diagnostic information about the ability of the fetus to respond to the stress of labour. One such method, the STAN fetal monitoring system has demonstrated clear clinical utility, however, unidentified adverse outcomes for women monitored by STAN have been shown to be a result of poor CTG interpretation, delay in taking action and non-adherence to guidelines, as well as poor signal quality. This article presents some of the findings of a 3-year retrospective review of STAN cases following its introduction into a UK maternity unit. Findings corroborate other study results which have highlighted that CTG interpretation is often poor, although a key issue in this review was a failure by practitioners to actually classify the CTG. Review findings, however, suggest that this might be more often a record keeping problem than an issue of clinical competence. Interesting findings around epidural use require further investigation. The findings of this review have clear implications for training and practice not only in units where STAN is used but more broadly