The influence of applying the NICE guideline on CTG interpretation and classification during labour and on resultant clinical management in Malta

Abstract

Background: Despite the existence of clinical guidelines to aid in cardiotocography (CTG) interpretation during labour, variation remains amongst observers. This study aimed to assess the influence of applying the NICE (2017) guideline on CTG interpretation and classification during the active first stage of labour and resultant clinical management at the public hospital in Malta. Further objectives include to note interobserver agreement within and between groups of obstetricians, obstetric trainees and midwives when interpreting and classifying CTGs and to examine the type of clinical management decisions taken, while following the NICE (2017) guideline. Methods: A total of 17 intrapartum CTGs were obtained retrospectively from inpatient records. Participants were recruited from the entire staff population (n=90) on voluntary basis, aiming to obtain a stratified sample. A survey containing the CTGs and questions based on the NICE guideline, regarding CTG interpretation, classification and clinical management was disseminated to participants. Responses were analysed between obstetricians, trainees and midwives using Fleiss’ Kappa statistic for interobserver agreement on CTG interpretation within and between groups while percentage frequencies were applied to analyse type of classification and management responses. Statistical software IBM® SPSS® version 28 and Minitab® version 21 were used. Results: A mixed sample of 25 participants was obtained, resulting in a response rate of 33.8%. High levels of agreement were achieved when interpreting decelerations, while poor agreement was observed for interpreting baseline FHR, accelerations and variability. Normal CTG classifications achieved the highest interobserver agreement amongst all groups; with midwives achieving highest kappa values but weak agreement (k=0.516; CI 95% 0.413-0.620; P 0.000). Variation was noted for clinical management options chosen for each trace. Participants chose to ‘expedite birth’ for 53% (n=17) of CTGs, even in normal traces. Conclusion: Despite following a standard guideline which is meant to aid in CTG interpretation and classification, interobserver agreement is still overall poor and variation remains a challenge. Future studies with larger samples are recommended as well as maintain regular CTG interpretation workshops in clinical practice.