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Isis Amer-Wåhlin

Publications and source records attributed to Isis Amer-Wåhlin.

6 recordsLinked to original sources
PubMed2006

United States multicenter clinical usage study of the STAN 21 electronic fetal monitoring system.

OBJECTIVE: The fetal electrocardiogram system for electronic fetal monitoring (EFM) (STAN S21, Neoventa Medical, Moelndal, Sweden) has led to improved perinatal outcomes in other countries. We aimed to assess the ability of United States (US) obstetricians to use this system appropriately for intrapartum care. STUDY DESIGN: A prospective nonrandomized trial was conducted in 6 sites. Enrollment required a singleton vertex fetus, >36 weeks' gestation, with indications for direct fetal monitoring during first stage of labor. Appropriate use was measured by negative predictive value (NPV) of nonintervention for fetuses with nonreassuring fetal heart rate (FHR) patterns, normal STAN readings, and normal neonatal outcomes with umbilical cord arterial pH >7.12; and percent agreement (PA) for intervention decisions with 3 STAN experts who conducted retrospective case reviews blinded to outcome. RESULTS: Five hundred and thirty patients were enrolled. An NPV of 95.2% was achieved while PA between investigators and STAN experts was 84%, and 90%, for intervention and nonintervention, respectively. No fetus with metabolic acidosis requiring intervention was missed by US clinicians. CONCLUSION: US clinicians used the STAN system appropriately in a manner similar to that of experienced STAN users.

Acidosis↗
PubMed2006

Outcome in obstetric care related to oxytocin use. A population-based study.

BACKGROUND: The purpose of this study was to investigate the delivery outcome in relation to oxytocin use in labor. METHODS: We studied 106,755 deliveries from 1995 to 2002 in the Perinatal Revision South, a population-based register comprising information from 10 hospitals in southern Sweden. RESULTS: Oxytocin use in labor increased from 27.6% in 1995/96 to 33.2% in 2001/02 (p<0.000006). Oxytocin was administered to 47.7% of the nulliparas and 18.5% of the multiparas. There were large differences between hospitals (range among nulliparas: 32.6-60.4%; among multiparas: 13.9-27.0%). After exclusion of deliveries with induction of labor and deliveries lasting >12 h, there was a significant association between oxytocin use and Apgar score < 7 at 5 min (OR 2.3; 95% CI 1.8-2.9), need for neonatal intensive care (OR 1.6; 95% CI 1.5-1.7), and operative delivery (OR 4.0; 95% CI 3.7-4.2). CONCLUSIONS: In deliveries with relatively short duration (< or =12 h), a significant association was seen between oxytocin use and adverse outcome. Even though the results are difficult to interpret, the significant difference between the use of oxytocin in different hospitals, as well as the increase of oxytocin use over time, calls for a randomized controlled study to elucidate the advantages and disadvantages of oxytocin use during labor and delivery.

Acidosis↗
PubMed2005

Fetal heart rate patterns and ECG ST segment changes preceding metabolic acidaemia at birth.

OBJECTIVES: To compare the rates of abnormal ST segment patterns of the ECG and cardiotocographic (CTG) abnormalities in fetuses with metabolic acidaemia at birth and controls. To evaluate the inter-observer agreement in interpretation of ST analysis and CTG. DESIGN: Case-control study. SETTING: Three University hospitals in southern Sweden. POPULATION: Cases and controls were selected from the Swedish randomised controlled trial on intrapartum monitoring, including 4966 fetuses monitored with a scalp electrode. METHODS: Two obstetricians independently assessed the CTG and ST traces of 41 fetuses with metabolic acidaemia at birth and 101 controls, blinded to group, outcome and all clinical data. They classified each CTG trace and ST analysis as abnormal or not abnormal, and whether there was indication to intervene according to the CTG or to the CTG + ST guidelines. If their classification differed, assessment by a third obstetrician determined the final classification. MAIN OUTCOME MEASURES: Rates of CTG and ST abnormalities and decisions to intervene. Rates of inter-observer agreement. RESULTS: CTG was classified as abnormal in 50% and ST in 63% of cases with acidaemia, and in 20% and 34% of controls, respectively. CTG abnormalities were judged to be indication for intervention in 45% and CTG + ST abnormalities in 56% of cases with acidaemia, and in 15% and 8% of controls, respectively. The proportion of agreement between the two initial observers was significantly higher for ST abnormalities (94%) than for CTG abnormalities (73%), and for indication to intervene according to CTG + ST (89%) than according to CTG alone (76%). CONCLUSIONS: The inter-observer agreement rate was higher for a decision to intervene based on CTG + ST than on CTG alone.

Acidosis↗
PubMed2004

Fetal ECG waveform analysis.

Fetal ECG waveform analysis as an adjunct to electronic fetal monitoring (EFM) has developed over the last 3 decades. From a multitude of potential parameters, ST waveform analysis has been documented to provide the information required to shift EFM from a screening device to a diagnostic tool that meets the standards of evidence-based medicine. This chapter details the experimental and clinical evolution of the STAN methodology for intrapartum fetal surveillance. Observational data formed the basis for cardiotocograph (CTG) and ST waveform analysis clinical guidelines. Data from two large, randomized controlled trials (6826 cases) are summarized together with the first analysis of the recently completed EU project of 7823 term fetuses monitored as part of the study to introduce ST analysis into clinical practice. The reduction in the incidence of newborns with marked neurological symptoms is supported by these findings. The detection of ST changes allowed earlier and more consistent intervention.

Animals↗
PubMed2003

Fetal electrocardiography in labor and neonatal outcome: data from the Swedish randomized controlled trial on intrapartum fetal monitoring.

OBJECTIVE: Cardiotocography plus automatic ST analysis of the fetal electrocardiography has been shown recently to reduce both the operative delivery rate for fetal distress and the cord artery metabolic acidosis rate. The purpose of this study was to analyze findings that were related to cases with a complicated/adverse neonatal outcome in the Swedish randomized controlled trial. STUDY DESIGN: Of the 4966 term fetuses that were included in the trial, all 351 newborn infants who required special neonatal care were identified. Cases of perinatal death, neonatal encephalopathy, or metabolic acidosis at birth were reviewed. RESULTS: Of the 29 fetuses with adverse/complicated neonatal outcome, 22 fetuses had cardiotocography and ST patterns that indicated a need for intervention, according to the cardiotocography plus ST clinical guidelines. The number of live-born with moderate or severe neonatal encephalopathy showed a significant decrease from 0.33% (8/2447 fetuses) in the cardiotocography-only group to 0.04% (1/2519 fetuses) in the cardiotocography plus ST group. CONCLUSION: Cardiotocography plus ST analysis provides accurate information about intrapartum hypoxia and may prevent intrapartum asphyxia and neonatal encephalopathy by giving a clear alert to the staff members who are in charge.

Acidosis↗