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887: Characteristics of variable decelerations and prediction of fetal acidemia
Poster Session V
ajog.org
Execution of treatment protocol from moment of diagnosis (t0) Labetalol (n=29) Ketanserin (n=51) P-value Median time from t0 until target value, in minutes [IQR]
123 [32.0 - 278.5] 107 [54.0 - 193.0]
Median time from t0 until first antihypertensive medication, in minutes [IQR] 5.0 [0.0 - 24.5]
0.85
68.0 [32.0 - 117.0] <0.01
Median time from t0 until tiv, in minutes [IQR]
121 [76.8 - 226.8] 70.0 [35.8 - 121.5] 0.02
Receiving intravenous therapy, n (%)
14 (48.3)
50 (98.0)
<0.01
RESULTS: This is an interim analysis. So far 333 traces of the 435 are analysed. 304 fetuses had normal lactate concentration at FBS, and 29 were acidemic. Mean area and duration (total and per decel) differed between acidemic and nonacidemic fetuses, whereas total number and depth of decels did not. ROC analysis was used to evaluate the ability to predict fetal acidemia. The best discriminator was the area and the duration of the decelerations with an area under curve (AUC) of 0.670 and 0.656 respectively. The depth of decelerations was less predictive of fetal acidemia (AUC 0.577). CONCLUSION: Duration and area are the characteristics of variable decelerations that best correspond to fetal acidemia during labor. The depth of the decelerations is of less importance.
887 Characteristics of variable decelerations and prediction of fetal acidemia Erika Gyllencreutz1,2, Ke Lu3, Farhad Abtahi3,4, Kaj Lindecrantz3,4, Lennart Nordstro¨m1, Pelle Lindqvist4, Malin Holzmann1
Mean values of deceleration characteristics 60 minutes preceding FBS Normal lactate at FBS (no. 304) Lactacidemia at FBS (no. 29) p-value
1
Dep of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden, 2Dep Ob Gyn, Östersund hospital, Östersund, Sweden, 3School of Technology and Health, Royal Institute of Technology, Stockholm, Sweden, 4 CLINTEC, Karolinska Institutet, Stockholm, Sweden
OBJECTIVE: One important feature in FHR monitoring is the
occurrence of decelerations. However, several attributes of decelerations that are seen as important, have weak scientific grounds. Several experts and national guidelines consider the magnitude of the beat loss in decelerations to be of great importance, i.e. the 60ies rule. One recent study has shown that deceleration area best corresponds to fetal acidemia at birth. Umbilical acid-base status is influenced by several factors, whereas fetal scalp blood in immediate connection to occurrence of FHR decelerations is a more reliable measure. Our aim was to investigate how different characteristics of variable decelerations correspond to fetal hypoxia during labor. Our hypothesis is that the depth of decelerations is less predictive of fetal acidemia than duration and area. STUDY DESIGN: During a 2 year study period, there were 1070 deliveries at Karolinska University Hospital where fetal blood sampling (FBS) had been performed. The 435 CTG traces with variable decelerations were examined the 60 minutes preceding the first FBS in each recording. In collaboration with KTH, a MATLAB (MathWorks Inc., USA) program is developed to automatically detect and characterize each individual deceleration. The computer program’s ability to detect decelerations and calculate their characteristics i.e., duration, area and depth had been validated against two obstetricians prior to the study with the result of a good reliability. The outcome measure was fetal lactate concentration at FBS, and levels > 4.8 mmol/L were considered as fetal acidemia.
tot no decels
21.5
22.8
total area (beats)
411.3
568.0
0.319 <0.001
total duration (sec)
918.8
1158.4
0.001
total depth (bpm)
998.6
1129.0
0.145
area per decel (beats)
19.3
24.5
0.004
duration per decel (sec) 43.8
52.3
0.001
depth per decel (bpm)
48.8
0.221
46.4
888 Fetal heart rate abnormalities among smallversus appropriate- for gestational age: utilization of pattern recognition software Suneet P. Chauhan for the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network, Bethesda, MD
OBJECTIVE: To compare the type of fetal heart rate (FHR) patterns
during the last hour of labor among small for gestational age (SGA; birthweight < 10% for GA) vs. appropriate for gestational age (AGA; birthweight at 10-89%). STUDY DESIGN: For this secondary analysis of a randomized trial on intrapartum fetal ECG ST-segment analysis, we excluded women with chorioamnionitis, lack of FHR tracing > 30 min before delivery, and anomalous newborns. FHR patterns were categorized by computerized pattern recognition software (PeriCALM Patterns). An enhanced race-ethnicity-specific Alexander’s birthweight nomogram was used to categorize newborns as SGA or AGA. For SGA and AGA, we compared the composite neonatal morbidity (CNM) which was defined as any of the following: intrapartum fetal death, Apgar score 3 or less at 5 minutes, neonatal seizure, cord artery pH < 7.10,
Supplement to JANUARY 2017 American Journal of Obstetrics & Gynecology
S507
ajog.org
Execution of treatment protocol from moment of diagnosis (t0) Labetalol (n=29) Ketanserin (n=51) P-value Median time from t0 until target value, in minutes [IQR]
123 [32.0 - 278.5] 107 [54.0 - 193.0]
Median time from t0 until first antihypertensive medication, in minutes [IQR] 5.0 [0.0 - 24.5]
0.85
68.0 [32.0 - 117.0] <0.01
Median time from t0 until tiv, in minutes [IQR]
121 [76.8 - 226.8] 70.0 [35.8 - 121.5] 0.02
Receiving intravenous therapy, n (%)
14 (48.3)
50 (98.0)
<0.01
RESULTS: This is an interim analysis. So far 333 traces of the 435 are analysed. 304 fetuses had normal lactate concentration at FBS, and 29 were acidemic. Mean area and duration (total and per decel) differed between acidemic and nonacidemic fetuses, whereas total number and depth of decels did not. ROC analysis was used to evaluate the ability to predict fetal acidemia. The best discriminator was the area and the duration of the decelerations with an area under curve (AUC) of 0.670 and 0.656 respectively. The depth of decelerations was less predictive of fetal acidemia (AUC 0.577). CONCLUSION: Duration and area are the characteristics of variable decelerations that best correspond to fetal acidemia during labor. The depth of the decelerations is of less importance.
887 Characteristics of variable decelerations and prediction of fetal acidemia Erika Gyllencreutz1,2, Ke Lu3, Farhad Abtahi3,4, Kaj Lindecrantz3,4, Lennart Nordstro¨m1, Pelle Lindqvist4, Malin Holzmann1
Mean values of deceleration characteristics 60 minutes preceding FBS Normal lactate at FBS (no. 304) Lactacidemia at FBS (no. 29) p-value
1
Dep of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden, 2Dep Ob Gyn, Östersund hospital, Östersund, Sweden, 3School of Technology and Health, Royal Institute of Technology, Stockholm, Sweden, 4 CLINTEC, Karolinska Institutet, Stockholm, Sweden
OBJECTIVE: One important feature in FHR monitoring is the
occurrence of decelerations. However, several attributes of decelerations that are seen as important, have weak scientific grounds. Several experts and national guidelines consider the magnitude of the beat loss in decelerations to be of great importance, i.e. the 60ies rule. One recent study has shown that deceleration area best corresponds to fetal acidemia at birth. Umbilical acid-base status is influenced by several factors, whereas fetal scalp blood in immediate connection to occurrence of FHR decelerations is a more reliable measure. Our aim was to investigate how different characteristics of variable decelerations correspond to fetal hypoxia during labor. Our hypothesis is that the depth of decelerations is less predictive of fetal acidemia than duration and area. STUDY DESIGN: During a 2 year study period, there were 1070 deliveries at Karolinska University Hospital where fetal blood sampling (FBS) had been performed. The 435 CTG traces with variable decelerations were examined the 60 minutes preceding the first FBS in each recording. In collaboration with KTH, a MATLAB (MathWorks Inc., USA) program is developed to automatically detect and characterize each individual deceleration. The computer program’s ability to detect decelerations and calculate their characteristics i.e., duration, area and depth had been validated against two obstetricians prior to the study with the result of a good reliability. The outcome measure was fetal lactate concentration at FBS, and levels > 4.8 mmol/L were considered as fetal acidemia.
tot no decels
21.5
22.8
total area (beats)
411.3
568.0
0.319 <0.001
total duration (sec)
918.8
1158.4
0.001
total depth (bpm)
998.6
1129.0
0.145
area per decel (beats)
19.3
24.5
0.004
duration per decel (sec) 43.8
52.3
0.001
depth per decel (bpm)
48.8
0.221
46.4
888 Fetal heart rate abnormalities among smallversus appropriate- for gestational age: utilization of pattern recognition software Suneet P. Chauhan for the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network, Bethesda, MD
OBJECTIVE: To compare the type of fetal heart rate (FHR) patterns
during the last hour of labor among small for gestational age (SGA; birthweight < 10% for GA) vs. appropriate for gestational age (AGA; birthweight at 10-89%). STUDY DESIGN: For this secondary analysis of a randomized trial on intrapartum fetal ECG ST-segment analysis, we excluded women with chorioamnionitis, lack of FHR tracing > 30 min before delivery, and anomalous newborns. FHR patterns were categorized by computerized pattern recognition software (PeriCALM Patterns). An enhanced race-ethnicity-specific Alexander’s birthweight nomogram was used to categorize newborns as SGA or AGA. For SGA and AGA, we compared the composite neonatal morbidity (CNM) which was defined as any of the following: intrapartum fetal death, Apgar score 3 or less at 5 minutes, neonatal seizure, cord artery pH < 7.10,
Supplement to JANUARY 2017 American Journal of Obstetrics & Gynecology
S507