Kati Ojala

A comparison of intrapartum automated fetal electrocardiography and conventional cardiotocography—a randomised controlled study

Objective  To examine whether intrapartum monitoring by means of automatic ST analysis (STAN) of fetal electrocardiography could reduce the rate of neonatal acidemia and the rate of operative intervention during labour, compared with monitoring by means of cardiotocography (CTG).

Arterial embolization and prophylactic catheterization for the treatment for severe obstetric hemorrhage

Background.  To evaluate indications, efficacy, and complications associated with arterial embolization and prophylactic balloon catheterization in the management of obstetric hemorrhage at a university hospital.

ST Analysis of the Fetal Electrocardiogram in Intrapartum Fetal Monitoring: A Meta-Analysis.

OBJECTIVE: To compare the effects of ST-waveform analysis in combination with cardiotocography with conventional cardiotocography for intrapartum fetal monitoring. DATA SOURCES: We searched MEDLINE, Embase, and PubMed for randomized controlled trials (RCTs) evaluating ST-waveform analysis for intrapartum fetal monitoring. METHODS OF STUDY SELECTION: We identified RCTs that compared ST-waveform analysis and conventional cardiotocography for intrapartum fetal monitoring of singleton pregnancies in cephalic presentation beyond 34 weeks of gestation and evaluating at least one of the following: metabolic acidosis, umbilical cord pH less than 7.15, umbilical cord pH less than 7.10, umbilical cord pH less than 7.05, umbilical cord pH less than 7.00, Apgar scores less than 7 at 5 minutes, admittance to the neonatal intensive care unit, need for intubation, presence of hypoxic ischemic encephalopathy, perinatal death, operative delivery, and number of fetal blood samplings. TABULATION, INTEGRATION, AND RESULTS: Five RCTs, which included 15,352 patients, met the selection criteria. Random-effects models were used to estimate the combined relative risks (RRs) of ST analysis compared with conventional cardiotocography. Compared with conventional cardiotocography, ST analysis showed a nonsignificant reduction in metabolic acidosis (RR 0.72, 95% confidence interval 0.43–1.19, number needed to treat [NNT] 357). ST analysis significantly reduced the incidence of additional fetal blood sampling (RR 0.59, 95% confidence interval 0.44–0.79, NNT 11), operative vaginal deliveries (RR 0.88, 95% confidence interval 0.80–0.97, NNT 64), and total operative deliveries (RR 0.94, 95% confidence interval 0.89–0.99, NNT 64). For other outcomes, no differences in effect were seen between ST analysis and conventional cardiotocography, or data were not suitable for meta-analysis. CONCLUSION: The additional use of ST analysis for intrapartum monitoring reduced the incidence of operative vaginal deliveries and the need for fetal blood sampling but did not reduce the incidence of metabolic acidosis at birth.

Effectiveness of electronic fetal monitoring with additional ST analysis in vertex singleton pregnancies at >36 weeks of gestation: an individual participant data metaanalysis

OBJECTIVE The purpose of this study was to assess the effectiveness of electronic fetal monitoring (EFM) alone and with additional ST analysis (EFM + ST) in laboring women with a singleton term pregnancy that is in cephalic presentation in the prevention of metabolic acidosis by the application of individual patient data metaanalysis. STUDY DESIGN We conducted an individual patient data metaanalysis using data from 4 randomized trials, which enabled us to account for missing data and investigate relevant subgroups. The primary outcome was metabolic acidosis, which was defined as an umbilical cord-artery pH <7.05 and a base deficit that had been calculated in the extra cellular fluid compartment >12 mmol/L. We performed 8 explanatory subgroup analyses for 8 different endpoints. RESULTS We analyzed data from 12,987 women and their newborn infants. Metabolic acidosis was present in 57 women (0.9%) in the EFM + ST group and 73 women (1.1%) in the EFM alone group (relative risk [RR], 0.76; 95% CI, 0.53-1.10). Compared with EFM alone, the use of EFM + ST resulted in a reduction in the frequency of instrumental vaginal deliveries (RR, 0.90; 95% CI, 0.83-0.99) and fetal blood samples (RR, 0.49; 95% CI, 0.44-0.55). Cesarean delivery rates were comparable between both groups (RR, 0.99; 95% CI, 0.91-1.09). Subgroup analyses showed that EFM + ST resulted in fewer admissions to a neonatal intensive care unit for women with a duration of pregnancy of >41 weeks (RR, 0.61; 95% CI, 0.39-0.95). CONCLUSION EFM + ST does not reduce the risk of metabolic acidosis, but it does reduce the need for instrumental vaginal deliveries and fetal blood sampling.

Interobserver agreement in the assessment of intrapartum automated fetal electrocardiography in singleton pregnancies

Objective. To study interobserver agreement in the assessment of intrapartum automated fetal electrocardiogram ST interval analysis (STAN). Design. Observational study. Setting. Labor ward in tertiary level university hospital. Sample. Two hundred (140 reassuring and 60 non‐reassuring) STAN recordings on non‐selected women with singleton, vertex, term pregnancies were selected from our archive. Samples of 60‐min were analysed from the end of each recording, excluding the last 30 min before delivery. Methods. Three consultants, who had undergone STAN training and had clinical experience in using STAN, reviewed the recordings using cardiotocography (CTG) and ST information with no clinical data. The reviewers were asked to follow STAN guidelines and (1) to classify the CTG as normal, intermediary, abnormal, or preterminal, and (2) to make a clinical decision on labor management. Main outcome measures. Interobserver agreement evaluated by weighted kappa (κw) values and the proportion of agreement. Results. In CTG classification, the interobserver agreement between three observers was moderate (κw, 0.47–0.48). The proportion of agreement was 56–59%. In clinical decision‐making, κw values varied from 0.47 to 0.60, and the proportion of agreement was 80–86%. Conclusions. In non‐selected term pregnancies, the interobserver agreement among experienced obstetricians in the classification of CTG and clinical decision‐making according to STAN guidelines is moderate at best.

Neonatal outcomes after the obstetric near-miss events uterine rupture, abnormally invasive placenta and emergency peripartum hysterectomy - prospective data from the 2009-2011 Finnish NOSS study.

Neonatal outcomes after the maternal obstetric near‐miss complications of uterine rupture, abnormally invasive placenta, and emergency peripartum hysterectomy were assessed.

Cardiotocography and ST analysis for intrapartum fetal monitoring.

Sir, In their article ‘Swedish randomized controlled trial of cardiotocography only versus cardiotocography plus ST analysis of fetal ECG revisited: analysis of data according to standard versus modified intention-to-treat principle’ (1) Isis Amer-Wåhlin et al. reported a reanalysis of their previous randomized controlled trial data published 10 years ago (2). In the original publication (2) the study population was reported to consist of 4966 enrolled and randomized cases, 2447 of which were assigned to the cardiotocography (CTG)-only group and 2519 to the CTG+ST analysis group (as shown in Figure 2 of the article). In their recent reanalysis, however, the study population consisted of 5049 randomized cases; 2484 in the CTG-only group and 2565 in the CTG+ST analysis group. Unfortunately, the authors did not provide any explanation why the study population increased by 83 cases. They also did not report the clinical characteristics of the enlarged study population. We have two further concerns regarding the outcome data of the 2011 article. First, the numbers of operative deliveries and fetal blood samples were not reported. Secondly, the neonatal outcome data were classified in five groups (A–E, Table 1) based on the availability and validity of acid-base data. In our opinion, only group A with valid umbilical cord artery and vein data is fully concordant with the initial primary outcome of the trial, i.e. the rate of umbilical-artery metabolic acidosis. Group E contains cases with no umbilical cord data but assumed metabolic acidosis based on neonatal blood samples or calculated according to expected rates of metabolic acidosis. Including such generated data in the reanalysis as shown in Table 3 [‘ITT (current analysis) and ITT (including imputed data)’] is misleading. As cord blood gas values may change rapidly after delivery (3), analyses should be performed and compared in a standardized manner, as in the original study setting. As the effectiveness of ST analysis as an adjunct to CTG in fetal intrapartum monitoring has been, and will be, a subject of systematic reviews and meta-analyses, including our current work to update a systematic review (4) for the Managed Uptake of Medical Methods program in Finland, the outcome data of the relevant trials would be most valuable if reported as comprehensively and unambiguously as possible. Jaana Leipälä, MD, PhD1,∗ Kati Ojala, MD, PhD2, Vedran Stefanovic, MD, PhD3, Marjukka Mäkelä, MD, PhD, M.Sc1 1National Institute for Health and Welfare, Finnish Office for Health Technology Assessment (Finohta), Helsinki, 2Department of Obstetrics and Gynecology, Oulu University Hospital. Oulu, 3Department of Obstetrics and Gynecology, Helsinki University Hospital, principal trainer for fetal intrapartum monitoring by STAN in the Helsinki area, Helsinki.

Authors response to: A comparison of intrapartum automated fetal electrocardiography and conventional cardiotocography—a randomised controlled study

Sir, We have read the interesting comments toward our study1 made by Dr Majeed et al. and appreciate their valuable contribution. The number of newborns in the STAN group with cord artery pH < 7.10 was 41, and in 6 (15%) cases the registration was judged inadequate. The number of newborns with pH < 7.05 was 20, and number of inadequate registrations was 4 (20%). The STAN units can be used as conventional cardiotocography (CTG) machines if information of fetal ECG is not available for any reason. Secondly, Dr Majeed questioned what would happen if the cases of inadequate registration were sorted out. In the article, the results are counted on intention-to-treat basis. When the cases of inadequate registration are sorted out, the incidence of pH < 7.05 is 2.5% in the STAN group versus 1.1% in CTG group, (P = 0.052), pH < 7.10 is 5.5 versus 4.7% (P = 0.525), and of metabolic acidosis 1.3 versus 0.7% (P = 0.291), respectively. Within each subgroup, the results are line with the original results, yet the difference between STAN and CTG does not reach statistical significance in any subgroup. However, we can hardly imagine that ideal circumstances without any confounding factor could be reached in real life better than in a study setting. That is why we think that the original rather than corrected results reflect better the potential of the new method. The proportion of inadequate STAN registrations, 10.6%, was similar to the figures quoted earlier in literature. In our view the registration problem seems to be mainly related to the electrode with which an adequate signal could not be obtained. The incidence of inadequate registrations did not change during the study period. Finally, Dr Majeed pointed out the fact that in our study population the neonatal seizures (n = 2) and encephalopathy (n = 1) occurred only in the CTG group. The incidence of these events was far too low to allow a meaningful comparison between the groups. j