Non-Invasive Glucose Sensing Technologies and Products: A Comprehensive Review for Researchers and Clinicians.

Diabetes Mellitus incidence and its negative outcomes have dramatically increased worldwide and are expected to further increase in the future due to a combination of environmental and social factors. Several methods of measuring glucose concentration in various body compartments have been described in the literature over the years. Continuous advances in technology open the road to novel measuring methods and innovative measurement sites. The aim of this comprehensive review is to report all the methods and products for non-invasive glucose measurement described in the literature over the past five years that have been tested on both human subjects/samples and tissue models. A literature review was performed in the MDPI database, with 243 articles reviewed and 124 included in a narrative summary. Different comparisons of techniques focused on the mechanism of action, measurement site, and machine learning application, outlining the main advantages and disadvantages described/expected so far. This review represents a comprehensive guide for clinicians and industrial designers to sum the most recent results in non-invasive glucose sensing techniques' research and production to aid the progress in this promising field.

Short-Term Effects of Dexamethasone versus Betamethasone on Ultrasonic Measures of Fetal Well-Being: Cohort from a Blinded, Randomized Trial.

INTRODUCTION: Maternal corticosteroid administration for anticipated preterm birth is common; however, the corticosteroid effect on fetal ultrasound and cardiotocograph (CTG) remains contested. This study aimed to evaluate short-term ultrasound and CTG impact of (a) dexamethasone versus betamethasone (b) pooled corticosteroid effect. METHODS: Substudy of blinded randomized trial of dexamethasone versus betamethasone (given <34 weeks). Umbilical artery (UA), middle cerebral artery (MCA), ductus venosus (DV), and uterine artery Doppler, myocardial performance index (MPI), biophysical profile (BPP), and CTG measured pre-corticosteroid then 1, 2, 4, and 7 days post-corticosteroid. RESULTS: Of 47 fetuses (39 singleton; 4 dichorionic, diamniotic twins; and 4 monochorionic, diamniotic twins) in the February 2012-2013 period, 24 received dexamethasone and 23 betamethasone at average gestation 29.8 ± 2.9 weeks. Thirteen pregnancies (30%) had pre-corticosteroid fetal concerns (estimated weight <10th centile and/or abnormal UA/MCA Doppler). Few significant differences were seen post-corticosteroid: DV pulsatility index and right MPI initially decreased 15-20%, and average BPP decreased slightly on days 1-2. There were no major differential effects of dexamethasone versus betamethasone. DISCUSSION/CONCLUSION: No substantive post-corticosteroid effects were seen for most ultrasound/CTG measures in fetuses with heightened preterm birth risk but predominantly normal pre-corticosteroid measures. Clinically, this suggests avoiding overreliance on individual measures for delivery decisions post-corticosteroid; equally, multiple/marked ultrasound changes suggest true pathology and not corticosteroid effect.

Bimanual examination for clot evacuation: a retrospective cohort study of women with postpartum haemorrhage after vaginal delivery.

BACKGROUND: Bimanual clot evacuation (BCE) is a simple clinical manoeuvre that may reduce need for surgical intervention in the management of severe postpartum haemorrhage (PPH). We sought to determine whether performing BCE in cases of severe PPH after vaginal birth reduces the need for surgical intervention. METHODS: A retrospective chart review of women who delivered vaginally with a severe PPH between January 1, 2011 and December 31, 2014 in a single tertiary women's hospital in Sydney, Australia was conducted. Severe PPH was classified as a blood loss ≥1000mls. The need for surgical management (including operating theatre uterine exploration or evacuation, intrauterine balloon tamponade, repair of significant trauma, uterine or internal iliac artery ligation, B-Lynch suture insertion or hysterectomy) was the primary outcome measure, as expressed by need for operating theatre utilisation. RESULTS: From a cohort of 438, 149 women (34.0%) had BCE, of whom 29 (19.5%) required surgical management compared to 103 of 289 women with no BCE (35.6%); an odds ratio (OR) of 0.38 for BCE (confidence interval 0.20-0.72; p = 0.003). Early BCE (< 1 h of delivery) was associated with a further reduction in surgery (OR 0.24; confidence interval 0.08-0.70; p = 0.009) compared to late BCE (> 1 h of delivery). There was no reduction in estimated blood loss (p = 0.86) or blood transfusion (p = 0.71) with BCE. CONCLUSION: Our study suggests BCE reduces theatre utilisation in the context of severe PPH following vaginal delivery. Prospective trials are needed to determine whether BCE should be endorsed as a treatment modality for PPH post-vaginal delivery.

Three-dimensional US Fractional Moving Blood Volume: Validation of Renal Perfusion Quantification.

Background Three-dimensional (3D) fractional moving blood volume (FMBV) derived from 3D power Doppler US has been proposed for noninvasive approximation of perfusion. However, 3D FMBV has never been applied in animals against a ground truth. Purpose To determine the correlation between 3D FMBV and the reference standard of fluorescent microspheres (FMS) for measurement of renal perfusion in a porcine model. Materials and Methods From February 2017 to September 2017, adult pigs were administered FMS before and after measurement of renal 3D FMBV at baseline (100%) and approximately 75%, 50%, and 25% flow levels by using US machines from two different vendors. The 3D power Doppler US volumes were converted and segmented, and correlations between FMS and 3D FMBV were made with simple linear regression (r2). Similarity and reproducibility of manual segmentation were determined with the Dice similarity coefficient and 3D FMBV reproducibility (intraclass correlation coefficient [ICC]). Results Thirteen pigs were studied with 33 flow measurements. Kidney volume (mean Dice similarity coefficient ± standard deviation, 0.89 ± 0.01) and renal segmentation (coefficient of variation = 12.6%; ICC = 0.86) were consistent. The 3D FMBV calculations had high reproducibility (ICC = 0.97; 95% confidence interval: 0.96, 0.98). The 3D FMBV per-pig correlation showed excellent correlation for US machines from both vendors (mean r2 = 0.96 [range, 0.92-1.0] and 0.93 [range, 0.78-1.0], respectively). The correlation between 3D FMBV and perfusion measured with microspheres was high for both US machines (r2 = 0.80 [P < .001] and 0.70 [P < .001], respectively). Conclusion The strong correlation between three-dimensional (3D) fractional moving blood volume (FMBV) and fluorescent microspheres indicates that 3D FMBV shows excellent correlation to perfusion and good reproducibility. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Morrell et al in this issue.

The impact of caseload midwifery, compared with standard care, on women's perceptions of antenatal care quality: Survey results from the M@NGO randomized controlled trial for women of any risk.

BACKGROUND: The measurement and interpretation of patient experience is a distinct dimension of health care quality. The Midwives @ New Group practice Options (M@NGO) randomized control trial of caseload midwifery compared with standard care among women regardless of risk reported both clinical and cost benefits. This study reports participants' perceptions of the quality of antenatal care within caseload midwifery, compared with standard care for women of any risk within that trial. METHODS: A trial conducted at two Australian tertiary hospitals randomly assigned participants (1:1) to caseload midwifery or standard care regardless of risk. Women were sent an 89-question survey at 6 weeks postpartum that included 12 questions relating to pregnancy care. Ten survey questions (including 7-point Likert scales) were analyzed by intention to treat and illustrated by participant quotes from two free-text open-response items. RESULTS: From the 1748 women recruited to the trial, 58% (n = 1017) completed the 6-week survey. Of those allocated to caseload midwifery, 66% (n = 573) responded, compared with 51% (n = 444) of those allocated to standard care. The survey found women allocated to caseload midwifery perceived a higher level of quality care across every antenatal measure. Notably, those women with identified risk factors reported higher levels of emotional support (aOR 2.52 [95% CI 1.87-3.39]), quality care (2.94 [2.28-3.79]), and feeling actively involved in decision-making (3.21 [2.35-4.37]). CONCLUSIONS: Results from the study show that in addition to the benefits to clinical care and cost demonstrated in the M@NGO trial, caseload midwifery outperforms standard care in perceived quality of pregnancy care regardless of risk.

How well do women understand and remember information in labour versus in late pregnancy? A pilot randomised study.

Medical informed consent is the process by which a 'competent', non-coerced individual receives sufficient information including risks of a medical procedure and gives permission for it to occur. The capacity to give an informed consent might be impaired during labour. This study aimed to examine women's abilities to understand and remember during labour. Women were prospectively recruited at 36 weeks of gestation and randomised to undertake questionnaires which assessed their ability to understand and remember information. They were randomised to: (1) information given in labour only, written format (2) information in labour, verbal (3) information at 36 weeks plus labour, written (4) information at 36 weeks plus labour, verbal. Immediate comprehension and retention was assessed at 36 weeks, in labour, and 24-72 hours after birth. Forty-nine women completed the questionnaires regarding understanding and retention of information at 36 weeks, six intrapartum, and five postpartum (90% attrition). Women receiving information at 36 weeks and in labour versus in labour had a higher comprehension of pregnancy-related information, its retention, and total score. Women receiving information in late pregnancy and labour may comprehend and retain it better than women only receiving information during labour. Given small sample size, further research is needed to support these preliminary findings. Impact statement What is already known on this subject? The evidence regarding the capacity of labouring women to give informed consent is largely based on women's self-reported experiences or expert opinions and has mixed findings. Existing guidelines recommend that an informed consent should be given antenatally for both clinical practice and research. Studies show that obtaining an informed consent antenatally is neither feasible nor widely implemented. What do the results of this study add? A novel approach to providing empirical evidence regarding women's capacity to comprehend and retain information during labour. Our study confirms the difficulty with antenatal recruitment for intrapartum research. What are the implications of these findings for clinical practice and/further research? This raises ethical concerns regarding the current intrapartum research in which consent is largely sought at the time of the study. Emphasises the need to explore the question 'Do labouring women have the capacity to consent to research?' in order to ensure that women are protected during labour.

Automation of the Fetal Right Myocardial Performance Index to Optimise Repeatability.

OBJECTIVES: To compare the repeatability and degree of absolute agreement of an automated fetal right myocardial performance index (MPI) algorithm with manual measurements along with the impact of MPI observer experience on these two aspects. METHODS: Prospective cross-sectional study of 65 uncomplicated singleton pregnancies from 22 to 39 weeks' gestation. Image analysis of double-waveform right MPI measurements was conducted first with a MATLAB automated MPI software and then independently by an experienced and an inexperienced observer. Intraclass correlation coefficients (ICCs) and 95% confidence intervals (95% CI) were used to evaluate manual and automated intra- and interobserver repeatability. In addition, Bland-Altman plots were used to determine the degree of absolute agreement. RESULTS: Successful automation was performed on 63 cases (97%) showing repeatability ICCs of: 0.83 manual intraobserver; 0.77 manual interobserver; 1.00 automated. The degree of absolute agreement between manual and automated values was: inexperienced observer ICC 0.43 (95% CI 0.21-0.62); experienced observer ICC 0.76 (95% CI 0.63-0.85). CONCLUSION: Automation of right MPI demonstrates a superior reproducibility over manual measurements and reduces the experience required for successful analysis. This may lend a greater clinical applicability to MPI, and future studies to develop an automated universal reference range would be useful.

Use of the Myocardial Performance Index in Decreased Fetal Movement Assessment: A Case-Control Study.

OBJECTIVES: To determine whether there are any fetal cardiac function changes, as measured by the myocardial performance index (MPI), in pregnancies complicated by decreased fetal movement (DFM). METHODS: We performed a prospective cross-sectional case-control study of 50 DFM and 50 uncomplicated third-trimester pregnancies matched within 2 gestational weeks. Routine ultrasound growth and well-being parameters as well as MPI were measured. Average MPI measurements and its component values were compared between the DFM and the control group, as were demographics, other ultrasound data, and perinatal outcomes. RESULTS: Average left MPI (LMPI) and right MPI (RMPI) was similar between groups (LMPI: 0.54 ± 0.08 [DFM], 0.53 ± 0.08 [controls], p = 0.76; RMPI: 0.60 ± 0.12 (DFM), 0.59 ± 0.11 [controls], p = 0.79). However, subgroup analysis of DFM fetuses with (n = 20) or without (n = 30) any adverse perinatal outcome demonstrated modestly higher average RMPI and LMPI in the adverse perinatal outcome group (RMPI: 0.64 ± 0.08 vs. 0.57 ± 0.13, p = 0.02; LMPI: 0.56 ± 0.07 vs. 0.52 ± 0.07, p = 0.052). CONCLUSION: The MPI did not demonstrate clinically usable differences between the overall DFM population and controls. However, higher LMPI and RMPI values in the exploratory subgroup of DFM fetuses with adverse perinatal outcomes may warrant further exploration of the MPI in DFM.

Outcomes of stage I TTTS or liquor discordant twins: a single-centre review.

OBJECTIVES: To investigate rates of progression, regression and stabilisation and outcomes for stage I twin-twin transfusion syndrome (TTTS) and significant liquor discordant (LD) monochorionic diamniotic (MCDA) twins referred to the New South Wales Fetal Therapy Centre between June 2007 and May 2013. METHODS: Retrospective cohort study of 329 monochorionic referrals, of whom 47 had LD and 28 had stage I TTTS at presentation; 43 were stage I or higher at any time during surveillance. Clinical progression, rates of therapy, survival and associated complications were evaluated. RESULTS: Of stage I cases, 64% (18/28) remained stable or regressed, with 60% (6/10) of those progressing becoming at least stage II within 2 weeks. Of LD cases, 7/47 (15%) progressed to stage I TTTS, 8/47 (17%) to stage II or higher and 3/47 (6%) to selective intrauterine growth restriction (38% total). CONCLUSION: While a stable clinical picture was the most common outcome in stage I/LD presentations, progression to stage ≥ II TTTS occurred in 36 and 17% respectively, indicating that LD is not a benign finding. Rapid progression in the majority of progressive cases and modest overall survival rates support close surveillance of these pregnancies and investigation of laser therapy as a first-line treatment of stage I TTTS. © 2016 John Wiley & Sons, Ltd.

Utility of fetal MRI for workup of fetal central nervous system anomalies in an Australian maternal-fetal medicine cohort.

OBJECTIVES: To evaluate how fetal MRI is influencing current clinical practice and outcomes for central nervous system (CNS) anomalies in the Australian maternal-fetal medicine (MFM) setting. MATERIAL AND METHODS: Retrospective audit of cases January 2008-August 2013 referred for MFM ultrasound and MRI for suspected fetal CNS anomaly. Demographics, referral information, initial MFM diagnoses and investigations, MRI diagnoses, subsequent pregnancy management and perinatal outcome were examined. RESULTS: Fifty-seven women (41 singleton, 16 twin pregnancies) were seen at mean gestation of 23.7 ± 6.5 weeks. Major referral indications included ventriculomegaly (VM, 39%) and posterior fossa anomaly (PFA, 18%). MRI was performed at mean 27.2 ± 5.3 weeks. Diagnosis was altered from ultrasound in 31/57 cases (54%); 14 improving and 17 worsening prognosis. MRI findings worsening prognosis were more significant VM and PFA, agenesis of the corpus callosum, neuronal migration disorders and intraventricular haemorrhage. TOP or selective reduction occurred in 11 of 57 cases after full clinical workup (six where MRI worsened prognosis, five where MRI confirmed US poor prognosis). Mean gestation at birth was 37.2 ± 4.1 weeks for continuing pregnancies. There were nine cases of additional postnatal diagnoses, including four CNS anomalies. After neonatal workup, physical and/or developmental delay was anticipated for at least 14 of 43 (33%) infants. CONCLUSIONS: MRI added significant diagnostic information in about half the cases referred for workup of suspected CNS anomaly. In six of 17 cases where MRI worsened prognosis, TOP was chosen. Both additional CNS and non-CNS anomalies were diagnosed postnatally in 20%, emphasising the uncertain prognosis for, and evolution of, suspected CNS anomaly in fetuses.

The Aortic Isthmus: A Significant yet Underexplored Watershed of the Fetal Circulation.

The aortic isthmus (AoI) is a unique fetal watershed with a waveform reflecting its complex haemodynamic physiology. The systolic component represents left and right ventricular systolic ejection, and the diastolic component represents comparative downstream vascular impedance between the brachiocephalic and subdiaphragmatic fetal circulations. Several indices have been devised to quantify different components of the waveform, including the pulsatility index, resistance index, isthmic flow index, and recently the isthmic systolic index. There have been promising preliminary studies applying these indices to both cardiac (congenital) and extracardiac pathologies, including intrauterine growth restriction and twin-twin transfusion syndrome. However, the waveform's multifactorial origin has proven to be challenging, and the difficulty in separating various components of the waveform could explain that AoI evaluation does not have a clear clinical utility. Further research is underway to realise the full potential of this vessel in fetal cardiac and haemodynamically compromised pathological conditions. In this review article we outline the physiological origin of this Doppler waveform, describe in detail the various published indices, summarise the published literature to date, and finally outline potential future research and hopefully clinical applications.

A technique for the estimation of fractional moving blood volume by using three-dimensional power Doppler US.

PURPOSE: To (a) demonstrate an image-processing method that can automatically measure the power Doppler signal in a three-dimensional ( 3D three-dimensional ) ultrasonographic (US) volume by using the location of organs within the image and (b) compare 3D three-dimensional fractional moving blood volume ( FMBV fractional moving blood volume ) results with commonly used, unstandardized measures of 3D three-dimensional power Doppler by using the human placenta as the organ of interest. MATERIALS AND METHODS: This is a retrospective study of scans obtained as part of a prospective study of imaging placental biomarkers with US, performed with ethical approval and written informed consent. One hundred forty-three consecutive female patients were examined by using an image-processing technique. Three-dimensional FMBV fractional moving blood volume was measured on the vasculature from the uteroplacental interface to a depth 5 mm into the placenta by using a normalization volume 10 mm outside the uteroplacental interface and compared against the Virtual Organ Computer-aided AnaLysis ( VOCAL Virtual Organ Computer-aided AnaLysis ; GE Healthcare, Milwaukee, Wis) vascularization flow index ( VFI vascularization flow index ). Intra- and interobserver variability was assessed in a subset of 18 volumes. Wilcoxon signed rank test and intraclass correlation coefficients were used to assess measurement repeatability. RESULTS: The mean 3D three-dimensional FMBV fractional moving blood volume value ± standard deviation was 11.78% ± 9.30 (range, 0.012%-44.16%). Mean VFI vascularization flow index was 2.26 ± 0.96 (range, 0.15-6.06). Linear regression of VFI vascularization flow index versus FMBV fractional moving blood volume produced an R(2) value of 0.211 and was significantly different in distribution (P < .001). Intraclass correlation coefficient analysis showed higher FMBV fractional moving blood volume values than VFI vascularization flow index for intra- and interobserver variability; intraobserver values were 0.95 for FMBV fractional moving blood volume (95% confidence interval [ CI confidence interval ]: 0.90, 0.98) versus 0.899 for VFI vascularization flow index (95% CI confidence interval : 0.78, 0.96), and interobserver values were 0.93 for FMBV fractional moving blood volume (95% CI confidence interval : 0.82, 0.97) versus 0.67 for VFI vascularization flow index (95% CI confidence interval : 0.32, 0.86). CONCLUSION: The extension of an existing two-dimensional standardized power Doppler measurement into 3D three-dimensional by using an image-processing technique was shown in an in utero placental study. Three-dimensional FMBV fractional moving blood volume and VFI vascularization flow index produced significantly different results. FMBV fractional moving blood volume performed better than VFI vascularization flow index in repeatability studies. Further studies are needed to assess accuracy against a reference standard.

Pregnancy outcomes before and after institution of a specialised twins clinic: a retrospective cohort study.

BACKGROUND: Although specialised clinics for multiple pregnancies are recommended by several Obstetrics and Gynaecology governing bodies, studies examining outcome before and after introduction of such clinics remain few, were performed predominantly in North America in the 1990s, and either amongst dichorionic twin pregnancies only or where chorionicity was not specified. Our objective, in the modern setting with twins of known chorionicity, was to compare maternal and neonatal outcomes of twin pregnancies before and after commencement of a consultant-led, multidisciplinary twins clinic (TC). METHODS: Retrospective cohort study of 513 women, with birth of twins at ≥20 weeks' gestation, January 2007 to November 2011, at a metropolitan tertiary maternity hospital, Sydney, Australia. Demographic, pregnancy, and outcome data were obtained from hospital databases. Women receiving TC care (2009-2011) were compared to those receiving general antenatal clinic (ANC) care (2007-2010) and private care (2009-2011). Other models of care were excluded. Main outcome measures were total maternal inpatient stay, mode of birth, gestational age at birth, and neonatal nursery admission. RESULTS: 286 women were included in the main analyses: 84 attended ANC, 101 TC, and 101 a private obstetrician. TC women had similar demographics to ANC women and were slightly younger than private patients. TC women had lower Caesarean section rates (55% vs. 70% ANC and 76% private, p = 0.008) and fewer late preterm (34 + 0-36 + 6 weeks) births, (26%TC vs. 44% ANC and 41% private, p < 0.001). Median maternal inpatient stay was shorter in TC than ANC (7 vs. 8 days, p = 0.009) and similar to private (7 days). Nursery admission rates were higher in private patients (67% vs. 49% ANC and 47% TC, p = 0.001) and average birthweight lower (2283 g vs. 2501 g ANC and 2496 g TC, p < 0.001). CONCLUSIONS: Within a single centre, maternal and neonatal twin pregnancy outcomes varied significantly by model of care. Introducing a specialised twins clinic in our setting decreased Caesarean section rates, late preterm birth, and inpatient stay compared to ANC.

Importance of Pulse Repetition Frequency Adjustment for 3- and 4-Dimensional Power Doppler Quantification.

OBJECTIVES: To determine the influence of the pulse repetition frequency (PRF) and wall motion filter on the 3-dimensional (3D) power Doppler vascularization-flow index (VFI) and volumetric pulsatility index (PI) obtained from spatiotemporal image correlation (STIC) data sets acquired from a common carotid artery of a healthy participant. METHODS: We acquired 11 STIC data sets, 1 for each PRF value ranging from 0.6 to 9.0 kHz. Vascularization-flow index and volumetric PI values were determined from the 440 static 3D data sets contained in these STIC data sets. Additionally, 3 sets of radio-frequency data were acquired for offline processing of different wall motion filter values for PRF values of 0.6, 3.3, and 10 kHz. RESULTS: We constructed VFI curves and observed 2 patterns: a flattened pattern with a low PRF and a triphasic pattern with a high PRF, correlating with the known pulsed wave Doppler profile of this vessel. Volumetric PI values were around 0 for low PRF settings and increased with increasing PRF. Analysis of the radiofrequency data showed that increasing wall motion filter values gradually filtered out the low-velocity power Doppler signals while retaining the higher-velocity ones, allowing the distinction of integrated power Doppler signal velocity throughout the cardiac cycle. CONCLUSIONS: We conclude that the PRF and wall motion filter dramatically influence 3D power Doppler indices and the volumetric PI, and the use of PRF values in which minimum VFI values are measured during the diastolic phase in the spectral Doppler wave may validate the use of the volumetric PI.

Is There a Measurable Difference between the Left and Right Modified Myocardial Performance Indices, and Does This Change to Reflect Unilateral Myocardial Dysfunction in Pathology?

INTRODUCTION: Fetal cardiac dysfunction may manifest itself unilaterally as right and left ventricles differing in design, function and load, measurable as differing in myocardial performance indices (MPIs). We wished to define this difference ('delta-MPI' or DMPI), present its normal range and pilot its use in pathological pregnancy. MATERIAL AND METHODS: Prospective cross-sectional study of 324 normal singleton fetuses (16-38 weeks of gestation). Left and right modified MPI (LMPI and RMPI) were performed during a single examination using the 'peak' valve click technique. Thirty-seven pathological singleton and monochorionic diamniotic twin pregnancies were compared as pilot data. RESULTS: Modified MPIs (mean ± SD) were 0.45 ± 0.06 (LMPI) and 0.47 ± 0.09 (RMPI), being similar at 18 weeks' gestation with DMPI increasing slightly throughout pregnancy (0.02 ± 0.08). Both singleton intrauterine growth restriction (IUGR) and recipient twin-twin transfusion syndrome (TTTS) showed significantly elevated RMPI, LMPI and DMPI, most pronounced for DMPI (450 and 500% increase, respectively; p < 0.01). DMPI acquisition rates were 83.3% normal and 87.0% pathological. DISCUSSION: We demonstrate for the first time differing intrafetal LMPI and RMPI in a large gestational cohort, with this difference increasing with gestational age. Pilot data confirm the potential for DMPI as a tool to assess unilateral myocardial function in singleton IUGR and recipient twins in TTTS, and further studies are under way to evaluate its clinical utility.

The (Pulsed-Wave) Doppler Fetal Myocardial Performance Index: Technical Challenges, Clinical Applications and Future Research.

Functional cardiovascular assessment is becoming an increasingly important tool in the study of fetal pathology. The myocardial performance index (MPI) is a parameter measuring global myocardial function. Since its introduction, several studies have proposed methods to improve its reproducibility and have constructed normative reference ranges. Fetal heart evaluation using the MPI is technically challenging, requiring specific training and expertise, and a consensus has yet to be reached on the method of delineating the time periods used to calculate the index. Despite these limitations, it has been shown to be a useful and highly sensitive parameter of dysfunction in a number of fetal pathologies. Further research is warranted into the effect of pathology on MPI, parameters of unilateral cardiac strain that utilise MPI, and automation of the MPI to encourage incorporation of the MPI as a useful tool in clinical practice.

Development of normal gestational ranges for the right myocardial performance index in the Australian population with three alternative caliper placements.

OBJECTIVES: To construct gestational age-adjusted reference ranges for the right fetal modified myocardial performance index (RMPI) in an Australian population and to assess the influence of valve click caliper position on constituent time intervals and the RMPI. METHODS: A prospective cross-sectional study of RMPI from 235 normal fetuses at 17-38 weeks of gestation was performed. Two Doppler waveforms were obtained: tricuspid and pulmonary valves for 'a' and 'b' readings, respectively. The ultrasound machine settings were: Doppler sweep velocity 15 cm/s, angle of insonation <15°, minimal gain, and wall motion filter 300 Hz. The 'a' and 'b' intervals were measured at three different caliper positions in each fetus: at the beginning of the original valve clicks ('original'), at the beginning of the reflected tricuspid and pulmonary closure clicks ('reflected') and at the peak of valve clicks ('peak'). RMPI was calculated as (a - b)/b. The three readings were obtained and averaged per examination, with intraobserver repeatability assessed by intraclass correlation coefficient (ICC) and 95% CI. RESULTS: For 'original', 'reflected' and 'peak' RMPI, mean ± SD, ICC (95% CI) were: 0.53 ± 0.10, 0.86 (0.83-0.89); 0.48 ± 0.10, 0.84 (0.81-0.87) and 0.48 ± 0.10, 0.89 (0.87-0.91), respectively. The RMPI increased by approximately 15% as gestation increased and decreased slightly with increasing heart rate. CONCLUSION: This is the first publication of reference ranges for RMPI based on caliper position. All methods showed good ICC, including the 'peak' method which we have previously proposed for routine use based on its repeatability and ease of identification when measuring the myocardial performance index.

Collaboration in maternity care is achievable and practical.

BACKGROUND: Enhancing collaboration has been highlighted as a marker for future success in maternity care, although this suggestion comes with little methodological guidance. This study assessed the efficacy of a collaborative partnership between obstetric doctors and midwives providing Midwifery Group Practice (MGP) care. METHODS: A retrospective analysis was undertaken with notes from weekly case review meetings held between the obstetricians and midwives over a 12-month period; audio recordings and a prospective analysis of 16 meetings with verbal contributions of the different professions; the number and types of cases discussed and referred, medical records kept at these meetings and a professional satisfaction questionnaire. Consistency of care was measured against the Australian National Midwifery Guidelines for Consultation and Referral. RESULTS: Of the 337 women booked with MGP, 50% were discussed at least once. Of these, 35% were referred for consultation with an obstetrician. Women as 'Patients' were most commonly discussed, followed by educational discussions and anecdotes with equal verbal contributions from midwives and doctors. Plans for each case were recorded 97% of the time, and adhered to 90% of the time. A high level of consistency of care between similar cases (75% of the time) and with the consultation and referral guidelines (85% of the time) were achieved. Professional satisfaction with this model of care rated highly for both groups. CONCLUSION: Inter-professional collaboration between midwifery and obstetric staff is highly attainable within this model of care. This study reinforces the effectiveness of collaboration in the MGP model of care for women of all risk levels and should encourage other maternity care providers to consider adopting this collaborative model.

Australian maternity reform through clinical redesign.

The current Australian national maternity reform agenda focuses on improving access to maternity care for women and their families while preserving safety and quality. The caseload midwifery model of care offers the level of access to continuity of care proposed in the reforms however the introduction of these models in Australia continues to meet with strong resistance. In many places access to caseload midwifery care is offered as a token, usually restricted to well women, within limited metropolitan and regional facilities and where available, places for women are very small as a proportion of the total service provided. This case study outlines a major clinical redesign of midwifery care at a metropolitan tertiary referral maternity hospital in Sydney. Caseload midwifery care was introduced under randomised trial conditions to provide midwifery care to 1500 women of all risk resulting in half of the publicly insured women receiving midwifery group practice care. The paper describes the organisational quality and safety tools that were utilised to facilitate the process while discussing the factors that facilitated the process and the barriers that were encountered within the workforce, operational and political context.

The ethics of obtaining consent in labour for research.

BACKGROUND: It is widely acknowledged that the pregnant population is a vulnerable and potentially disadvantaged one with regard to research. We sought to evaluate compliance with this concept by examining current Australian practices of obtaining consent for research during labour through the published literature and from Australian Human Research Ethics Committees (HRECs) as well as reviewing the relevant literature. METHODS: We surveyed Australian HRECs requesting information about their opinions and/or practices surrounding the ethics of research consent during labour or birth. In addition, a literature search was performed to find randomised controlled trials (RCTs) involving interventions during labour in Australia in the last five years. RESULTS: Of the HREC respondents, 75% believed it to be ethical to obtain consent for research in labour, 87% would require additional expert assistance to approve, 57% felt the partner should be involved and all proposed research scenarios were thought to require protocol changes. Recent local RCTs reflected a variety of consent strategies, each having their limitations. CONCLUSIONS: An under-used but potentially useful strategy may be staged recruitment and consent. Despite the evidence supporting labour as a time requiring increased acuity for informed consent, there is little to suggest that this knowledge is being applied to current Australian HREC and RCT practices. We suggest that further practical guidelines be devised to aid researchers and human ethics committees.