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Håkan Norén

Publications and source records attributed to Håkan Norén.

6 recordsLinked to original sources
PubMed2006

STAN in clinical practice--the outcome of 2 years of regular use in the city of Gothenburg.

OBJECTIVE: The purpose of this study was to monitor the introduction of the STAN-methodology (Noventa Medical, Moelndal, Sweden). STUDY DESIGN: This was a prospective observational study covering the total population of deliveries at term during 2 years. Four thousand eight hundred and thirty out of 14,687 term pregnancies were monitored using the STAN S 21 fetal heart monitor and the associated clinical guidelines. Cord artery metabolic acidosis, neonatal outcome, and rates of operative deliveries for fetal distress were assessed. RESULTS: The annual rate of STAN usage increased from 28.1% to 37.7% and was associated with a significant reduction in metabolic acidosis rate in the total population from 0.76% to 0.44% (P < .05). The compliance with the clinical guidelines increased in cases requiring intervention. The rates for moderate/severe hypoxic neonatal encephalopathy were consistently low, 0.55 and 0.68 per 1000 deliveries, respectively, and corresponding to previous findings. The rate of operative delivery did not change during the 2 years in the total population. CONCLUSION: Increasing STAN usage provided consistent improvements in fetal outcome equalling those noted in the Swedish randomized controlled trial (RCT) without increasing operative interventions for fetal distress.

Acidosis↗
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↗
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↗
PubMed2004

Fetal scalp pH and ST analysis of the fetal ECG as an adjunct to CTG. A multi-center, observational study.

OBJECTIVE: To evaluate the relationships between scalp-pH and CTG plus ST waveform analysis of the fetal ECG (STAN) clinical guidelines as indicators of intrapartum hypoxia in term fetuses born with cord artery acidemia. STUDY DESIGN: Data from 6999 term deliveries monitored by the STAN (R) S 21 as part of an EU multi-center study on clinical implementation of the STAN methodology for intrapartum fetal surveillance were analyzed. We identified 911 cases where a scalp-pH was obtained, including 53 cases with cord artery acidemia (pH < 7.06). Lag times between ST events and scalp-pH and time to delivery were related to cord artery metabolic and respiratory acidosis and neonatal outcome. RESULTS: 43 fetuses were identified by CTG plus ST as being in need of intervention 31 (25-46) minutes before delivery (median, 95% Cl). In five, no indications were given and in another five there were inadequate data. Fifteen cases with metabolic acidosis required special neonatal care, all 14 cases adequately monitored on STAN had indications to intervene for 19 minutes or more. In 30 adequately recorded cases, fetal blood sampling (FBS) was obtained within the last hour of labor. In 22 cases, FBS was obtained 13 (7-24) minutes after STAN guidelines had indicated abnormality and in eight no ST changes had occurred at time of FBS. The corresponding FBS data were pH 7.10 (7.01-7.15) and pH 7.21 (7.08-7.31), respectively, P = 0.01. In cases of metabolic acidosis, scalp-pH fell 0.01 units per minute after a baseline T/QRS rise was recorded during the second stage of labor. Apart from one newborn that died at 2 h from E. Coli septicemia, none of the neonates were affected neurologically. CONCLUSION: Cardiotocography plus ST analysis provides accurate information about intrapartum hypoxia similar to that obtained by scalp-pH.

Acidosis↗
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.

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