Abstract
Physiological interpretation of cardiotocograph (CTG) involves determining the combination or sequence of features of the fetal heart rate to recognise different types of fetal hypoxic or non-hypoxic (e.g., chorioamnionitis) stresses, as well as scrutinising the CTG trace to differentiate features suggestive of fetal compensatory responses from decompensation. The Fetal Monitoring Checklist was recommended in 2017, and this has been recently endorsed by the International Expert Consensus Statement on Physiological Interpretation of CTG produced by more than 50 CTG experts from over 20 countries. The aim of the Fetal Monitoring Checklist is to exclude or to identify features suggestive of pre-existing fetal compromise by assessing the oxygenation of fetal central organs, placental function and the wider clinical context. This enables the frontline clinicians to ask the question “Is THIS fetus FIT to undertake the progressively hypoxic journey of human labour?” However, some pre-existing risk factors may manifest after the onset of established labour due to the super-imposed hypoxic stress. Similarly, intra-amniotic infection following a recent spontaneous prelabour rupture of membranes may be silent during the incubation period, but it may manifest during labour. In such cases, the use of the Fetal Monitoring Checklist may lead to the clinicians concluding that the “Fetus is FIT for Labour”, although, there is increased risk of fetal compromise with the passage of time and intrapartum super-imposed hypoxic stress. The intrapartum “FIT-CAT” (FIT for labour -Clinical Anticipation Tool) is designed to aid frontline clinicians to anticipate the changes on the CTG which are likely to occur during labour, based on the identified antenatal or intrapartum risk factors. This intrapartum anticipation tool may enable the timely recognition of features on the CTG which heralds the onset of fetal decompensation in fetuses who are deemed “FIT” to commence labour with pre-existing risk factors and/or develop intrapartum risk factors. Prompt recognition and appropriate management based on individualisation of care and the understanding of the impact of clinical context on the CTG trace may help improve perinatal outcomes.