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STAN in clinical practice—The outcome of 2 years of regular use in the city of Gothenburg

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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.

Section snippets

Material and methods

The 2 maternity wards located at Sahlgren's University Hospitals; Oestra and Moelndal cover a population of 870,000 and were equipped with 8 STAN S 21 units from August to September 2000 after the educational process had been ongoing during the summer months. An additional 3 STAN units were used during the last 6 months of the study. These are large labor ward units, with approximately 4000 deliveries per year each and 300 members of staff. Continuous fetal monitoring (conventional EFM) is the

Results

During a 2-year period starting October 1, 2000 and finishing September 30, 2002, 14,687 deliveries entered active labor with a gestational age >36 completed weeks. Of these, 4830 (32.9%) were monitored with STAN.

Table III provides the relative distribution of indications for use of the STAN monitor based on the first 700 cases monitored at the labor ward with no previous STAN experience.

Table IV gives the characteristics of the pregnancies monitored with STAN separated into the first and

Comment

It is the aim of fetal monitoring in labor to timely identify the fetus at risk for neonatal and long-term morbidity without unnecessarily increasing the instrumental delivery rate. The development and validation of ST analysis of the fetal ECG and the STAN methodology for fetal surveillance in labor has included a long series of studies, including 2 randomized controlled trials4, 8 leading on to positive conclusions in the Cochrane library.10 However, it can always be argued that a clinical

Acknowledgments

The authors gratefully acknowledge the support from Neoventa Medical AB. The EU Commission has provided support through its Innovation grant IPS-1999-00029. The data analysis has been part of an EU supported Network of Excellence programme, BIOPATTERN.

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