CTG was introduced 45 years ago as a screening tool to predict fetal hypoxia and enable obstetricians and midwives to analyse the changes of the fetal heart rate during labour to avoid intrapartum hypoxic – ischaemic injury. There has not been an improvement in the rate of cerebral palsy and perinatal deaths, however a significant increase in caesarean section and operative deliveries rate has been noted. CTG has a 60% false-positive rate and present guidelines encourage the visual interpretation of CTG based on “pattern recognition”, which has a high intra-observer variability. Knowledge of fetal physiology is necessary to adequately interpret and deal with the findings on the CTG.
The authors believe that it is possible to reduce unnecessary operative interventions and improve perinatal outcomes if the wider clinical picture is considered, incorporate antepartum/intrapartum risk factors, use additional tests of fetal well-being and a more physiology based approach. Clinicians need to understand the physiology behind the fetal heart rate changes and react accordingly.
The article gives you valuable information about technical aspects, features on CTG, classification, fetal physiopathology, types of hypoxia, management and additional tests of fetal well-being such as ST Analysis: “The advantage is the continuous information on the oxygenation of a central organ, the heart, instead of information of a peripheral hypoxia as shown by fetal blood sampling. A recent meta-analysis has concluded that ST-Analyser reduces not only FBS rate but also the total operative delivery rate and neonatal metabolic acidosis rate.”
Abstract – Pinas and Chandraharan
