Study of Assessing the Efficacy of Intrapartum Fetal Monitoring and Fetal Scalp Blood pH in Predicting Fetal Jeopardy

This present prospective study “ Assessing the Efficacy of Intrapartum fetal monitoring and fetal scalp blood pH in predicting fetal jeopardy ” was carried out at Government Kasturba Gandhi Hospital Madras Medical College, Chennai during the period October 2004 – August 2005. • Hundred patients in active phase of labour were selected with inclusion and exclusion criterias. • In hundred cases PIH and post EDD gestation constituted 63% of study population. • Majority of the study group (56%) were between 19-24 years of age. • 59% of this study group were Primi gravidas. • 60% of the study group had clear liquor. • CTG is reactive in 28%f cases and non reactive in 72% of cases. • In 72% of non reactive CTG changes persistant Tachycardia >180 was present in 25% of cases. variable deceleration of different severity was seen in 48.61% of cases. Sinusoidal pattern was seen in 1.39% of cases. • 39% of study group had birth weight of 2.5-3 Kg. But there is no correlation between Birth weight, CTG abnormalities and neonatal outcome. • In reactive CTG, 92.86% were delivered vaginally, 7.14% were delivered by caesarean section . In non reactive CTG 45.84% were delivered vaginally and 54.17% were delivered by caesarean section. • In normal CTG Fetal distress (Apgar <7) were present in 10.71% of cases. In non reactive CTG Apgar <7 was present in 33.34% of cases. There was no neonatal death in reactive CTG. (p value: 0.169) • Scalp blood pH estimation was done in 72 cases of non reactive CTG. In reactive CTG , Scalp pH estimation was not done. • Among the 72 cases, normal pH was present in 47 cases . Acidotic pH was seen in 25 cases . • Among non acidotic pH Apgar >7 was seen in 95.74% cases and Apgar <7 was seen in 4.26% of cases. Among acidotic pH Apgar <7 was seen in 88% of cases. • In normal pH 51.06% were delivered vaginally and 48.94% were delivered by caesarean section. • In abnormal pH 36% were delivered vaginally 64% delivered by caesarean section. (p value 0.003) • There was no neonatal death in non acidotic pH babies. • In acidotic pH there was 2 neonatal death. One baby of mother with severe PIH wth scalp pH of 7.14 delivered by caesarean section immediately died after 5 minutes due to meconium aspiration syndrome(MAS). Other one with severe oligohydramnios with scalp pH 7.23 delivered by caesarean section immediately with 5 minutes Apgar <6 was died after two days with hypoxic ischaemic encephalopathy. • There is no correlation between colour of liquor and neonatal outcome. • Among 72 cases of non reactive CTG caesarean section was done in 54.17% of cases. Addition of FBS and scalp pH estimation reduced the unnecessary caesarean section rate. • Abnomral CTG is associated with negative predictive value of 89.29%. But low positive predictive value of 33.33 %. This means that a normal trace indicates that the fetus is not hypoxic. Abnormal CTG is associated with large number of false positive. • For normal perinatal outcome if we take Apgar >7 as an end point. Fetal scalp pH has a positive predictive value of 95. 74 % and negative predictive value of 88%. • By the use of intrapartum CTG and scalp blood pH, we can reduce the perinatal death due to intrapartum hypoxia. CONCLUSION: Intrapartum CTG if properly used is a sensitive indicator of fetal well being. But its poor specificity must be improved by appropriately timed scalp blood sampling in carefully selected cases. The use of continuous electronic fetal monitoring has been associated with great reduction in the incidence of unexpected still birth. Arulkumaran and Gibb 199034 has reported that intra partum hypoxia was responsible for 14.5% of perinatal death in 1982 (where only intermittent auscultation was performed). After introduction of continuous EFM during 1986-1992, the perinatal deaths came down to 7.9%. Edington et al 1975 : Parer 1979;26 Biswas et al 1995;25 showed similar reduction in perinatal mortality. Fetal respiratory acidosis secondary to uterine hypertonus or maternal metabolic acidosis secondary to fetal ketosis may produce false positive low pH value (