Pros and cons of additions like ‘Intelligent’ IA
Recently, there has been a tendency to demand detection of more and more FHR variations.9,14 These can be shown to add complexity without even theoretical benefits. One proposed ‘intelligent IA’ (in addition to flawed recommendation of actual ‘counting’) lumbers additional unproven burden of actively seeking FHR accelerations (following fetal movements or vaginal/abdominal examination etc.); and failing that unnecessarily switching over to CTG.7But, the absence of FHR accelerations (especially in low risk cases) is not in itself pathological even on CTG and hence doesn’t warrant commencing CTG in the first place.1-4 Thus, one can safely await detection of late decelerations on IA. Hence, accelerations need not be actively sought but noted when present only to differentiate the FHR baseline from them. There is further confused belief that the type of deceleration cannot be ascertained on IA.9,14When auscultation is only performed towards the end and after the uterine contraction, the decelerations detected lasting beyond the contractions are of ‘late’ type by definition.1,6,15,16 Another recommendation to detect ‘post-deceleration overshoots’ 14 seems a burdensome distraction, because these are very rare and inconsistent late features of fetal acidemia even on CTG to be clinically useful.17 A high-quality study of 5388 women showed that out of 57 babies with cord blood arterial pH below 7.10, none showed post-deceleration overshoots during labour.17 Hence, it would suffice just to detect late decelerations and not get distracted hearing for overshoots. Suggestion to look for quiet and active epochs (cycling) of FHR 14 for reassurance seems equally impractical, unproven and un-actionable. The concept of rise in baseline (within normal range) FHR during labour as an abnormal finding9 seems to come from uncontrolled unblinded retrospective reviews of known cases of birth asphyxia with its positive predictive value unknown (in the absence of persistent late decelerations). Such creeping additions without good evidence would increase switch over to CTG and medical intervention.