Computerised analysis of intrapartum fetal heart rate patterns and adverse outcomes in the INFANT trial

OBJECTIVE

To assess if a computerised decision support system reliably identified abnormal fetal heart rate (FHR) patterns in fetuses with adverse neonatal outcomes in the INFANT trial, and whether its use reduced substandard care.

DESIGN

Prospective cohort study within a randomised controlled trial.

SETTING

Twenty-four maternity units in the UK and Ireland.

POPULATION OR SAMPLE

A total of 46 614 labours between January 6 2010 and August 31 2013 in the INFANT trial.

METHODS

Panel review of intrapartum and neonatal care in infants with adverse outcome, and an assessment of the effectiveness of computerised interpretation of fetal heart rate in reducing substandard care. Descriptive analysis of other factors associated with adverse outcome.

MAIN OUTCOME MEASURES

Incidence and detection rate of abnormal fetal heart rate patterns, other characteristics associated with perinatal adverse outcome, and frequency of substandard care.

RESULTS

Computer interpretation of FHR patterns was deemed to be completely valid in only 24 of 71 (33.8%) cases of adverse outcome. On a scale of 0-10 (completely invalid to completely valid), 28 cases (39.4%) had a score of 6 or less, mainly due to lack of recognition of decelerations (15 cases), or reduced variability (seven cases), or failure to recognise tachysystole (five cases). There were multiple associated factors that modified the clinical assessment of FHR patterns. There was substandard care in 45/71 cases (63%).

CONCLUSION

A significant proportion of abnormal fetal heart rate patterns were not detected accurately by computer analysis, and its use did not reduce the incidence of substandard care.

FUNDING

UK National Institute for Health Research Health Technology Assessment Programme (project number 06.38.01).

TWEETABLE ABSTRACT

Improved recognition of abnormal fetal heart rate patterns is insufficient to reduce the incidence of substandard care.

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