The accuracy of prehospital triage decisions in English trauma networks - a case-cohort study

BACKGROUND

Care for injured patients in England is provided by inclusive regional trauma networks. Ambulance services use triage tools to identify patients with major trauma who would benefit from expedited Major Trauma Centre (MTC) care. However, there has been no investigation of triage performance, despite its role in ensuring effective and efficient MTC care. This study aimed to investigate the accuracy of prehospital major trauma triage in representative English trauma networks.

METHODS

A diagnostic case-cohort study was performed between November 2019 and February 2020 in 4 English regional trauma networks as part of the Major Trauma Triage Study (MATTS). Consecutive patients with acute injury presenting to participating ambulance services were included, together with all reference standard positive cases, and matched to data from the English national major trauma database. The index test was prehospital provider triage decision making, with a positive result defined as patient transport with a pre-alert call to the MTC. The primary reference standard was a consensus definition of serious injury that would benefit from expedited major trauma centre care. Secondary analyses explored different reference standards and compared theoretical triage tool accuracy to real-life triage decisions.

RESULTS

The complete-case case-cohort sample consisted of 2,757 patients, including 959 primary reference standard positive patients. The prevalence of major trauma meeting the primary reference standard definition was 3.1% (n=54/1,722, 95% CI 2.3 - 4.0). Observed prehospital provider triage decisions demonstrated overall sensitivity of 46.7% (n=446/959, 95% CI 43.5-49.9) and specificity of 94.5% (n=1,703/1,798, 95% CI 93.4-95.6) for the primary reference standard. There was a clear trend of decreasing sensitivity and increasing specificity from younger to older age groups. Prehospital provider triage decisions commonly differed from the theoretical triage tool result, with ambulance service clinician judgement resulting in higher specificity.

CONCLUSIONS

Prehospital decision making for injured patients in English trauma networks demonstrated high specificity and low sensitivity, consistent with the targets for cost-effective triage defined in previous economic evaluations. Actual triage decisions differed from theoretical triage tool results, with a decreasing sensitivity and increasing specificity from younger to older ages.

Exploring the experiences of people with urogynaecology conditions in the UK: a reflexive thematic analysis and conceptual model

BACKGROUND

Urogynaecological conditions, such as pelvic organ prolapse, urinary incontinence, and urinary tract infection, can have a profound impact on people's lives. The Independent Medicines and Medical Devices Safety Review highlights missed opportunities to prevent harm when patient voices are not incorporated into healthcare policy and practice. This resonates with the Women's Health Strategy for England. The National Institute for Health and Care Research (NIHR) Policy Research Programme funded this in-depth qualitative exploration of people's experiences of living with urogynaecological conditions, and of seeking healthcare treatment, to inform health and social care improvements in the UK.

METHODS

We conducted in-depth interviews online or by telephone (April 2021-December 2021) and used reflexive thematic analysis to develop themes that cut across urogynaecological conditions.

RESULTS

We spoke to seventy-four adults aged 22-84 across a range of backgrounds and lived experiences of urogynaecological conditions, including pelvic organ prolapse, urinary incontinence and persistent or recurring urinary tract infection. Eight themes were developed: [1] I get no respite from my own body; [2] I feel confined and separated; [3] I can no longer be 'me'; [4] I am constrained by stigma, shame and silence; [5] I feel fragmented and lost in the healthcare system; [6] I need to be heard, believed, and valued; [7] I need respect as an equal partner in healthcare; and [8] (Re)connected to a more open community.

CONCLUSIONS

High quality care focuses on the whole person rather than their body parts. Openness and candour support a shared decision-making model of care. A culture of shame can have a negative impact on access to health care and recovery.

Systolic function in dogs with pulmonic stenosis of different severities and the effect of balloon valvuloplasty

INTRODUCTION/OBJECTIVES

Pulmonic stenosis (PS) is one of the most common congenital heart diseases in dogs leading to right ventricular (RV) pressure overload, myocardial remodeling, and potential RV dysfunction. Our objectives were to investigate the extent of RV systolic dysfunction in canine PS and to examine the immediate influence of balloon valvuloplasty (BV) on systolic function.

ANIMALS, MATERIALS AND METHODS

This prospective study evaluated 72 dogs with PS and 86 healthy dogs. Echocardiographic parameters of systolic function included normalized tricuspid annular plane systolic excursion (N-TAPSE), normalized systolic myocardial tissue Doppler velocity of the lateral tricuspid annulus (N-RVFW-S'), fractional area change, and speckle-tracking longitudinal endocardial RV strain. Forty-four dogs underwent BV and were re-examined after surgery.

RESULTS

Systolic function at the basal segment of the RV was significantly lower in the PS group when compared to healthy dogs (mean N-TAPSE 4.29 ± standard deviation 1.18 mm/kg^0.285 vs. 5.60 ± 1.29 mm/kg^0.285; median N-RVFW-S' 5.28 [lower-upper 25% quantile 4.35-6.43 cm/s/kg^0.186] vs. 7.82 [6.73-8.79 cm/s/kg^0.186]; all P<0.001). Global longitudinal RV endocardial strain showed no significant difference between the two groups (-28.50 ± 6.23% vs. 28.61 ± 4.64%; P=0.886), but segmental strain analyses revealed basal hypo- and potential compensatory hyperkinesis of the apical RVFW. Furthermore, BV affected most parameters of systolic function, but not the segmental strain values and N-TAPSE.

CONCLUSIONS

Right ventricular basal longitudinal systolic function is decreased in dogs with PS in comparison to a healthy cohort. Regional and global function does not necessarily coincide.

Injured patients who would benefit from expedited major trauma centre care: a consensus-based definition for the United Kingdom

INTRODUCTION

Despite the importance of treating the 'right patient in the right place at the right time', there is no gold standard for defining which patients should receive expedited major trauma centre (MTC) care. This study aimed to define a reference standard applicable to the United Kingdom (UK) National Health Service major trauma networks.

METHODS

A one-day facilitated roundtable expert consensus meeting was conducted at the University of Sheffield, UK, in September 2019. An expert panel of 17 clinicians was purposively sampled, representing all specialities relevant to major trauma management. A consultation process was subsequently held using focus groups with Public and Patient Involvement (PPI) representatives to review and confirm the proposed reference standard.

RESULTS

Four reference standard domains were identified, comprising: need for critical interventions; presence of significant individual anatomical injuries; burden of multiple minor injuries; and important patient attributes. Specific criteria were defined for each domain. PPI consultation confirmed all aspects of the reference standard. A coding algorithm to allow operationalisation in Trauma Audit and Research Network data was also formulated, allowing classification of any case submitted to their database for future research.

CONCLUSIONS

This reference standard defines which patients would benefit from expedited MTC care. It could be used as the target for future pre-hospital injury triage tools, for setting best practice tariffs for trauma care reimbursement and to evaluate trauma network performance. Future research is recommended to compare patient characteristics, management and outcomes of the proposed definition with previously established reference standards.

PP39 What is the risk of major trauma following a fall down stairs? – A systematic review

Background

Specific mechanisms of injury are stated in pre-hospital triage tools to identify suspected cases of major trauma. Falls down stairs are common presentations in UK emergency departments, yet are frequently overlooked as a causative mechanism of major trauma. No prior systematic review has examined this association.

Methods

Seven internationally recognised literature databases and seven grey literature databases were screened utilising a common search strategy from inception until 31 December 2019. Abstracts were screened for relevance by a single reviewer. Full texts were screened and subsequently extracted by 3 separate reviewers against strict inclusion/exclusion criteria. A risk of bias assessment based on GRADE recommendations was performed. In the absence of study heterogeneity, a narrative synthesis was planned. The reporting of this systematic review followed PRISMA 2009 statement guidelines.

Results

5240 articles were identified from database searching, 89 articles had their full texts assessed for eligibility and 6 articles were included for qualitative synthesis. All studies were retrospective in nature and originated from more economically developed countries. 7431 patients who fell down stairs were analysed, of which, 707 (9.5%) met major trauma definitions. Falls down stairs resulted in a significantly increased risk of serious injury compared to other fall mechanisms (OR: 1.621, 95% CI: 1.381 – 1.902, p<0.0005). Analysis of confounding factors demonstrated age (OR: 2.59, 95% CI: 1.57 – 4.28, p<0.001) and alcohol intoxication (OR: 2.6, 95% CI: 1.4 – 4.7, p=0.001) to be significantly associated with major trauma. Risk of bias was moderate to high across all 6 studies.

Conclusion

This systematic review highlighted the paucity of literature surrounding the incidence of major trauma following falls down stairs.

A retrospective cohort study is currently being undertaken to analyse the risk of major trauma following falls down stairs. On completion, the results will be incorporated with the results of this systematic review.

Customized birth-weight centiles and placenta-related fetal growth restriction

OBJECTIVE

The value of using customized birth-weight centiles to improve the diagnostic accuracy for fetal growth restriction (FGR), in comparison with using population-based charts, remains a matter of debate. One potential explanation for the conflicting data is that most studies used measures of perinatal mortality and morbidity as proxies for placenta-mediated FGR, many of which are not specific and may be confounded by other factors such as prematurity. The aim of this study was to compare the diagnostic accuracy of small-for-gestational age (SGA) at birth, defined according to customized vs population-based charts, for associated abnormal placental pathology.

METHODS

This was a secondary analysis of data from a prospective cohort study on risk factors for placenta-mediated complications and abnormal placental pathology in low-risk nulliparous women. All placentae were sent for detailed histopathological examination by two perinatal pathologists. The primary exposure was SGA, defined as birth weight < 10^th centile for gestational age using either a customized (SGA_cust ) or a population-based (SGA_pop ) birth-weight reference. The outcomes of interest were one of three types of abnormal placental pathology associated with FGR: maternal vascular malperfusion (MVM), chronic villitis and fetal vascular malperfusion (FVM). Adjusted relative risks (aRR) with 95% CIs were estimated using modified Poisson regression analysis, with adjustment for smoking, body mass index and aspirin treatment.

RESULTS

A total of 857 nulliparous women met the study criteria. The proportions of infants identified as SGA based on the customized and population-based charts were 12.6% (108/857) and 11.4% (98/857), respectively. A diagnosis of SGA using either customized or population-based charts was associated with an increased risk of any placental pathology (aRR, 3.04 (95% CI, 2.29-4.04) and 1.60 (95% CI, 1.10-2.31), respectively) and MVM pathology (aRR, 12.33 (95% CI, 6.60-23.03) and 5.29 (95% CI, 2.87-9.76), respectively). SGA_cust , but not SGA_pop , was also associated with an increased risk for chronic villitis (aRR, 1.85 (95% CI, 1.07-3.18)) and FVM pathology (aRR, 2.48 (95% CI, 1.25-4.93)). SGA_cust had a higher detection rate for any placental pathology (30.3% vs 17.1%; P < 0.001), MVM pathology (63.2% vs 39.5%; P = 0.003) and chronic villitis (20.8% vs 8.3%; P = 0.007) than did SGA_pop , for a similar false-positive rate. This was mainly the result of a higher detection rate for abnormal pathology in the white and East-Asian subgroups and a lower false-positive rate for abnormal pathology in the South-Asian subgroup by SGA_cust than by SGA_pop . In addition, pregnancies in the SGA_cust group, but not those in the SGA_pop group, were more likely to be complicated by preterm birth and a low 5-min Apgar score than were the corresponding non-SGA group.

CONCLUSION

These findings suggest that customized birth-weight centiles may be superior to population-based birth-weight centiles in detecting FGR that is due to underlying placental disease. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Prehospital continuous positive airway pressure for acute respiratory failure: the ACUTE feasibility RCT

BACKGROUND

Acute respiratory failure is a life-threatening emergency. Standard prehospital management involves controlled oxygen therapy. Continuous positive airway pressure is a potentially beneficial alternative treatment; however, it is uncertain whether or not this treatment could improve outcomes in NHS ambulance services.

OBJECTIVES

To assess the feasibility of a large-scale pragmatic trial and to update an existing economic model to determine cost-effectiveness and the value of further research.

DESIGN

(1) An open-label, individual patient randomised controlled external pilot trial. (2) Cost-effectiveness and value-of-information analyses, updating an existing economic model. (3) Ancillary substudies, comprising an acute respiratory failure incidence study, an acute respiratory failure diagnostic agreement study, clinicians perceptions of a continuous positive airway pressure mixed-methods study and an investigation of allocation concealment.

SETTING

Four West Midlands Ambulance Service hubs, recruiting between August 2017 and July 2018.

PARTICIPANTS

Adults with respiratory distress and peripheral oxygen saturations below the British Thoracic Society's target levels were included. Patients with limited potential to benefit from, or with contraindications to, continuous positive airway pressure were excluded.

INTERVENTIONS

Prehospital continuous positive airway pressure (O-Two system, O-Two Medical Technologies Inc., Brampton, ON, Canada) was compared with standard oxygen therapy, titrated to the British Thoracic Society's peripheral oxygen saturation targets. Interventions were provided in identical sealed boxes.

MAIN OUTCOME MEASURES

Feasibility objectives estimated the incidence of eligible patients, the proportion recruited and allocated to treatment appropriately, adherence to allocated treatment, and retention and data completeness. The primary clinical end point was 30-day mortality.

RESULTS

Seventy-seven patients were enrolled (target 120 patients), including seven patients with a diagnosis for which continuous positive airway pressure could be ineffective or harmful. Continuous positive airway pressure was fully delivered to 74% of participants (target 75%). There were no major protocol violations/non-compliances. Full data were available for all key outcomes (target ≥ 90%). Thirty-day mortality was 27.3%. Of the 21 deceased participants, 14 (68%) either did not have a respiratory condition or had ceiling-of-treatment decision implemented that excluded hospital non-invasive ventilation and critical care. The base-case economic evaluation indicated that standard oxygen therapy was probably cost-effective (incremental cost-effectiveness ratio £5685 per quality-adjusted life-year), but there was considerable uncertainty (population expected value of perfect information of £16.5M). Expected value of partial perfect information analyses indicated that effectiveness of prehospital continuous positive airway pressure was the only important variable. The incidence rate of acute respiratory failure was 17.4 (95% confidence interval 16.3 to 18.5) per 100,000 persons per year. There was moderate agreement between the primary prehospital and final hospital diagnoses (Gwet's AC1 coefficient 0.56, 95% confidence interval 0.43 to 0.69). Lack of hospital awareness of the Ambulance continuous positive airway pressure (CPAP): Use, Treatment Effect and economics (ACUTE) trial, limited time to complete trial training and a desire to provide continuous positive airway pressure treatment were highlighted as key challenges by participating clinicians.

LIMITATIONS

During week 10 of recruitment, the continuous positive airway pressure arm equipment boxes developed a 'rattle'. After repackaging and redistribution, no further concerns were noted. A total of 41.4% of ambulance service clinicians not participating in the ACUTE trial indicated a difference between the control and the intervention arm trial boxes (115/278); of these clinician 70.4% correctly identified box contents.

CONCLUSIONS

Recruitment rate was below target and feasibility was not demonstrated. The economic evaluation results suggested that a definitive trial could represent value for money. However, limited compliance with continuous positive airway pressure and difficulty in identifying patients who could benefit from continuous positive airway pressure indicate that prehospital continuous positive airway pressure is unlikely to materially reduce mortality.

FUTURE WORK

A definitive clinical effectiveness trial of continuous positive airway pressure in the NHS is not recommended.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN12048261.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 7. See the NIHR Journals Library website for further project information.

Diagnostic accuracy of prehospital triage tools for identifying major trauma in elderly injured patients: A systematic review

BACKGROUND

Older adults with major trauma are frequently undertriaged, increasing the risk of preventable morbidity and mortality. The aim of this systematic review was to evaluate the diagnostic performance of prehospital triage tools to identify suspected elderly trauma patients in need of specialized trauma care.

METHODS

Several electronic databases (including MEDLINE, EMBASE, and the Cochrane Library) were searched from inception to February 2019. Prospective or retrospective diagnostic studies were eligible if they examined prehospital triage tools as index tests (either scored theoretically using observed patient variables or evaluated according to actual paramedic transport decisions) compared with a reference standard for major trauma in elderly adults who require transport by paramedics following injury. Selection of studies, data extraction, and risk of bias assessments using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool were undertaken independently by at least two reviewers. Narrative synthesis was used to summarize the findings.

RESULTS

Fifteen studies met the inclusion criteria, with 11 studies examining theoretical accuracy, three evaluating real-life transport decisions, and one assessing both (of 21 individual index tests). Estimates for sensitivity and specificity were highly variable with sensitivity estimates ranging from 19.8% to 95.5% and 57.7% to 83.3% for theoretical accuracy and real life triage performance, respectively. Specificity results were similarly diverse ranging from 17.0% to 93.1% for theoretical accuracy and 46.3% to 78.9% for actual paramedic decisions. Most studies had unclear or high risk of bias and applicability concerns. There were no obvious differences between different triage tools, and findings did not appear to vary systematically with major trauma prevalence, age, alternative reference standards, study designs, or setting.

CONCLUSION

Existing prehospital triage tools may not accurately identify elderly patients with serious injury. Future work should focus on more relevant reference standards, establishing the best trade-off between undertriage and overtriage, optimizing the role prehospital clinician judgment, and further developing geriatric specific triage variables and thresholds.

LEVEL OF EVIDENCE

Systematic review, level III.

Cost-effectiveness of out-of-hospital continuous positive airway pressure for acute respiratory failure: decision analytic modelling using data from a feasibility trial

Background

Standard prehospital management for Acute respiratory failure (ARF) involves controlled oxygen therapy. Continuous positive airway pressure (CPAP) is a potentially beneficial alternative treatment, however, it is uncertain whether this could improve outcomes and provide value for money. This study aimed to evaluate the cost-effectiveness of prehospital CPAP in ARF.

Methods

A cost-utility economic evaluation was performed using a probabilistic decision tree model synthesising available evidence. The model consisted of a hypothetical cohort of patients in a representative ambulance service with undifferentiated ARF, receiving standard oxygen therapy or prehospital CPAP. Costs and quality adjusted life years (QALYs) were estimated using methods recommended by NICE.

Results

In the base case analysis, using CPAP effectiveness estimates form the ACUTE trial, the mean expected costs of standard care and prehospital CPAP were £15,201 and £14,850 respectively and the corresponding mean expected QALYs were 1.190 and 1.128, respectively. The mean ICER estimated as standard oxygen therapy compared to prehospital CPAP was £5685 per QALY which indicated that standard oxygen therapy strategy was likely to be cost-effective at a threshold of £20,000 per QALY (67% probability). The scenario analysis, using effectiveness estimates from an updated meta-analysis, suggested that prehospital CPAP was more effective (mean incremental QALYs of 0.157), but also more expensive (mean incremental costs of £1522), than standard care. The mean ICER, estimated as prehospital CPAP compared to standard care, was £9712 per QALY. At the £20,000 per QALY prehospital CPAP was highly likely to be the most cost-effective strategy (94%).

Conclusions

Cost-effectiveness of prehospital CPAP depends upon the estimate of effectiveness. When based on a small pragmatic feasibility trial, standard oxygen therapy is cost-effective. When based on meta-analysis of heterogeneous trials, CPAP is cost-effective. Value of information analyses support commissioning of a large pragmatic effectiveness trial, providing feasibility and plausibility conditions are met.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-021-00404-8.

The diagnostic accuracy of pre-hospital assessment of acute respiratory failure

Introduction:

Acute respiratory failure (ARF) is a common medical emergency. Pre-hospital management includes controlled oxygen therapy, supplemented by specific management options directed at the underlying disease. The aim of the current study was to characterise the accuracy of paramedic diagnostic assessment in acute respiratory failure.

Methods:

A nested diagnostic accuracy and agreement study comparing pre-hospital clinical impression to the final hospital discharge diagnosis was conducted as part of the ACUTE (Ambulance CPAP: Use, Treatment effect and Economics) trial. Adults with suspected ARF were recruited from the UK West Midlands Ambulance Service. The pre-hospital clinical impression of the recruiting ambulance service clinician was prospectively recorded and compared to the final hospital diagnosis at 30 days. Agreement between pre-hospital and hospital diagnostic assessments was evaluated using raw agreement and Gwets AC1 coefficient.

Results:

77 participants were included. Chronic obstructive pulmonary disease (32.9%) and lower respiratory tract infection (32.9%) were the most frequently suspected primary pre-hospital diagnoses for ARF, with secondary contributory conditions recorded in 36 patients (46.8%). There was moderate agreement between the primary pre-hospital and hospital diagnoses, with raw agreement of 58.5% and a Gwets AC1 coefficient of 0.56 (95% CI 0.43 to 0.69). In five cases, a non-respiratory final diagnosis was present, including: myocardial infarction, ruptured abdominal aortic aneurysm, liver failure and sepsis.

Conclusions:

Pre-hospital assessment of ARF is challenging, with limited accuracy compared to the final hospital diagnosis. A syndromic approach, providing general supportive care, rather than a specifically disease-orientated treatment strategy, is likely to be most appropriate for the pre-hospital environment.

Mechanisms of Action of a Web-Based Intervention With Health Professional Support to Increase Adherence to Nebulizer Treatments in Adults With Cystic Fibrosis: Qualitative Interview Study

Background

Adherence to nebulizer treatments in adults with cystic fibrosis (CF) is often low. A new complex intervention to help adults with CF increase their adherence to nebulizer treatments was tested in a pilot randomized controlled trial (RCT) in 2 UK CF centers. Patients used a nebulizer with electronic monitoring capabilities that transferred data automatically to a digital platform (CFHealthHub) to monitor adherence over time and to a tailored website to display graphs of adherence data and educational and problem-solving information about adherence. A trained interventionist helped patients identify ways to increase their adherence.

Objective

This study aims to explore the mechanisms of action underpinning the intervention.

Methods

A qualitative interview study was conducted concurrently with a pilot RCT. In total, 25 semistructured interviews were conducted with 3 interventionists at 2 time points, 14 patients in the intervention arm of the trial, and 5 members of the multidisciplinary teams offering wider care to patients. A framework approach was used for the analysis.

Results

The intervention was informed by a theoretical framework of behavior change. There was evidence of the expected behavior change mechanisms of action. There was also evidence of additional mechanisms of action associated with effective telehealth interventions for self-management support: relationships, visibility, and fit. Patients described how building a relationship with the interventionist through face-to-face visits with someone who cared about them and their progress helped them to consider ways of increasing adherence to medication. Rather than seeing the visibility of adherence data to clinicians as problematic, patients found this motivating, particularly if they received praise about progress made. The intervention was tailored to individuals, but there were challenges in how the intervention fitted into some patients’ busy lives when delivered through a desktop computer.

Conclusions

The mechanisms of action associated with effective telehealth interventions for self-management operated within this new intervention. The intervention was modified to strengthen mechanisms of action based on these findings, for example, delivery through an app accessed via mobile phones and then tested in an RCT in 19 UK CF centers.

Trial Registration

International Standard Randomized Controlled Trial Number 13076797; http://www.isrctn.com/ISRCTN13076797

PP32 Major trauma triage tools study (MATTS) expert consensus meetings

Introduction

Major trauma triage tools are used to identify patients for bypass to Major Trauma Centres (MTCs). Bypass has been associated with improved patient outcomes following major trauma. The aim of the Major Trauma Triage Tools Study (MATTS) is to produce an evidence-based triage tool to be implemented across UK ambulance services.

Methods

Two independently chaired 1-day expert consensus meetings comprised of senior clinical professionals from specialties relevant to major trauma and prehospital triage were conducted as part of Phase 1 of the MATTS project, each with a distinct focus:

To define a reference standard of major trauma

Produce a new triage tool

Facilitated round table discussions were conducted with consensus developed through arbitration. In the first meeting a multi-domain reference standard defining major trauma patients with the potential to benefit from MTC care was determined. In the subsequent meeting triage tools were developed to select appropriate injured patients meeting this reference standard.

Results

Three tools were produced with a different diagnostic accuracy focus:

Sensitive – Maximising major trauma identification.

Specific – Preserving MTC care for the most severely injured patients

Balanced – A tool balancing sensitivity and specificity

Conclusion

The reference standard will form the basis of data analysis in Phase 2 of the project. The performance of the 3 differing tools will be tested in a dataset of routine ambulance service and TARN data. Following this, the most optimal triage tool will be assessed in clinical practice across 4 ambulance services.

01 Major trauma triage tools study (MATTS) triage tools summary

Introduction

The aim of this project is to identify major trauma triage tools currently in use by ambulance services in England, Wales and internationally and subsequently complete a detailed document analysis of these tools. The review will aim to detect the most commonly used predictors of major trauma whilst identifying the evidence behind them.

Methods

A variety of triage tools used internationally were acquired through analysis of systematic reviews freely available on PubMed. The 46 identified tools included: 40 adult/general, 4 paediatric-specific and 2 geriatric-specific tools. Following the acquisition of all triage tools, they were analysed by diagnostic criteria and a detailed spreadsheet produced. Each row of the spreadsheet represented a different triage criterion and each cell was colour coded to suggest the correct course of action for patient management.

Results

In total, 63 separate clinical features and triaging criteria were identified. These were categorised into five major groups (most common variables):

Physiology (GCS, Low BP).

Anatomy (Chest trauma, traumatic amputation).

Mechanism of injury (Falls, high speed RTC).

Modifiers for high risk groups (Age >55/65, pregnant)

Time limit to the nearest MTC (>45 minutes).

Additionally, crew concern is a potential predictor in 14 tools. Despite many tools using similar predictors, their respective predictor cut-points varied widely (e.g. from GCS ≤14 to <9).

From the tools assessed, two basic tool structures were discerned:

A flowchart style format (34 tools)

A points-based scoring system (7 tools)

Conclusions

The various major trauma triaging tools currently in use in the NHS and worldwide are highly varied. Although there are commonly used domains variable cut-points often varied. Given this significant difference between services’ tools, and variability of clinician interpretation of those criteria, large variations in standards of major trauma triaging are likely.

Pre-hospital CPAP for acute respiratory failure: the ACUTE feasibility and pilot randomised controlled trial

Introduction:

Acute respiratory failure (ARF) is a common and life-threatening medical emergency. Continuous positive airway pressure (CPAP) is a potentially beneficial alternative treatment; however, it is uncertain whether this could improve important outcomes in NHS ambulance services. The ACUTE study aimed to assess the feasibility of a large-scale pragmatic trial of pre-hospital CPAP.

Methods:

The study was a pilot randomised controlled trial of the O-Two system CPAP mask versus standard oxygen therapy, with concealed allocation in identical sealed boxes. Feasibility objectives estimated the incidence of eligible patients; the proportion recruited and allocated to treatment appropriately; adherence to allocated treatment; and retention and data completeness. The primary clinical endpoint was 30-day mortality. Ancillary studies included an ARF incidence study, ARF diagnostic agreement study, clinician perceptions of CPAP mixed methods study and investigation of allocation concealment.

Results:

Over 12 months, 77 patients were enrolled (target 120). CPAP was fully delivered in 74% (target 75%). There were no major protocol violations/non-compliances. Full data were available for all key outcomes (targets ≥ 90%). Thirty-day mortality was 27.3%. Of deceased patients, 14/21 (68%) either did not have a respiratory condition or had ceiling of treatment decisions implemented excluding hospital NIV and critical care.

Conclusion:

The ACUTE trial recruitment rate was below the target rate and feasibility was not demonstrated. Identification of patients who might benefit from pre-hospital CPAP was challenging. It appeared difficult to exclude conditions where CPAP would not work, or might be harmful, and to select appropriate patients where there was a meaningful chance of success, or where the potential advantages of pre-hospital CPAP would outweigh the burdens of more advanced and aggressive treatment. The limited compliance with CPAP, and the difficulty in identifying patients who could benefit from CPAP, indicate that pre-hospital CPAP is unlikely to materially reduce mortality. A definitive effectiveness trial of CPAP in the NHS is therefore not recommended.

PP22 Box randomisation- a novel method for allocation in pre-hospital randomised controlled trials: the ACUTE study experience

Background

Allocation concealment is essential to avoid selection bias in randomised trials. The ACUTE pilot trial compared the effectiveness of pre-hospital CPAP vs standard oxygen therapy for acute respiratory failure (ARF). The randomisation schedule was implemented, and treatment allocation concealed, with a novel method using identical boxes.

Methods

Investigation of allocation concealment in the ACUTE trial proceeded in 4 stages. Firstly, the characteristics of recruited ACUTE trial patients were compared across arms. Secondly, the findings of a weekly trial box audit log were examined. Thirdly, allocation concealment was explored in paramedic focus groups and survey. Finally, a convenience sample of West Midlands and Yorkshire Ambulance Service paramedics were presented with a random pair of ACUTE boxes from each trial arm, and asked to identify any differences. If a difference was noted, they were asked to indicate which box contained CPAP and why.

Results

The ACUTE study enrolled 77 participants (42 CPAP, 35 control). Baseline characteristics were similar, although patients in the CPAP arm appeared to have slightly more severe ARF. In week 10, audit of trial boxes revealed that intervention arm boxes were ‘rattling’, secondary to deflation of CPAP masks packaged under tension. All boxes were consequently re-packaged and resupplied. No comments in the paramedic survey, but a focus group participant stated that one box had appeared different when shaken. 278 paramedics participated in the observational study. 115 participants (41.4%) felt they were able to tell which box contained CPAP, predominantly due to weight difference. Of these, 81 paramedics (70%, p<0.05) were correct.

Conclusions

Although the majority of paramedics were unable to determine box contents, a significant minority correctly determined the CPAP arm. Taken together with the development of a ‘rattle’ during the trial, and slight baseline imbalance in characteristics of trial participants, loss of allocation concealment cannot be excluded.

PP28 ‘They are not silly people – they know the difference’: clinician focus group views on a pilot randomised controlled trial of prehospital continuous positive airway pressure (CPAP)

Background

Continuous positive airway pressure (CPAP) is not in widespread use in UK ambulance services, but could benefit patients with acute respiratory failure (ARF). As a new treatment in this context, clinician acceptability is an important factor in the feasibility of conducting definitive research in the prehospital arena.

Methods

As part of a pilot randomised controlled trial (the ACUTE study), nine trial-trained paramedics took part in three semi-structured focus groups. 204 trained staff had been given the opportunity to take part. The sample included six staff who had recruited to the trial, one who had not, and two who had withdrawn from it. Audio-recordings were transcribed and analysed thematically.

Results

Participants described facilitators to trial participation including: clear eligibility criteria and patient documentation, access to demonstration equipment, training away from the work environment, and repeated patient recruitment. Barriers to taking part included: the lack of protected time for training, inadequate workplace facilities for the electronic learning package used, adverse responses by receiving hospital staff, and infrequent patient exposure. Both paramedics who withdrew cited the inconvenience of carrying packs each shift. Some participants described anxiety and distress when opening packs to find a standard-care mask, and reported patients having similar reactions.

Conclusions

Future researchers could promote improved workplace computing facilities and increased provision of face-to-face training days, which were praised by participants in these focus groups, but limited to a single event distant from some staff. Greater stakeholder engagement by researchers could reduce the difficulties at hospital handover reported by some ambulance staff. Where blinding is not possible, the perceptions of clinicians and patients should be considered carefully, as this study shows both may have adverse emotional responses to being treated with standard care, particularly when prospective consent discussions describe the trial intervention as potentially beneficial.

PP25 ‘I wish there was CPAP in every box’: internet-based survey responses of clinicians recruiting to a pilot randomised controlled trial of continuous positive airway pressure (CPAP) for patients with acute respiratory failure

Background

Continuous positive airway pressure (CPAP) is not in widespread use in UK ambulance services, but could benefit patients with acute respiratory failure (ARF). As a new treatment in this context, clinician acceptability is an important factor in the feasibility of conducting definitive research in the prehospital arena.

Methods

As part of a pilot randomised controlled trial (the ACUTE study), recruiting clinicians were emailed after enrolling patients to either the CPAP or standard-care arm, and were asked to complete an optional, anonymous, internet-based survey. The survey used a mixture of closed questions, Likert-scaled answers and free text to explore staff views on both the treatment and the trial procedures. Quantitative responses were analysed descriptively, and qualitative answers thematically.

Results

Recruiting clinicians for all 77 patients were sent survey links, with 40 email responses received. Respondents felt confident diagnosing ARF and determining trial eligibility. CPAP-arm respondents found the equipment easy-to-use and felt it did not delay transport to hospital. Most standard-care respondents said they would have liked CPAP to be available to their patients. Respondents described varying responses from receiving hospital staff.

Conclusions

Prehospital CPAP seems acceptable to clinicians. Limitations of this survey are that it was targeted only at clinicians who have already opted to take part in the trial, and so may exclude a body of staff who find the treatment unacceptable at face value. Not all clinicians who enrolled patients completed the survey, which could suggest a response bias or simply a reflection of its optional nature within the trial. Future pilot studies could mandate an acceptability survey, and also seek the views of staff not taking part in the interventional study. Trial teams may need to better explain the rationale of comparing a new intervention with standard care, and offer more widespread hospital staff awareness sessions.

OR04-2 Aldosterone Induces Trained Immunity via Fatty Acid Synthesis

Hyperaldosteronism is associated with an increased cardiovascular risk in humans. Animal models show that aldosterone accelerates the development of atherosclerotic plaques, and suggest that this is, at least in part, mediated by activation of innate immune cells by aldosterone (1). Human data are scarce. We recently showed that monocytes can adopt a long-term pro-inflammatory phenotype after brief stimulation, which has been termed ‘trained immunity’ (2). Therefore, we tested the hypothesis that aldosterone induces ‘trained immunity’ by investigating the functional, immunometabolic and epigenetic effects of aldosterone on human monocytes in vitro. Human monocytes were exposed to vehicle, aldosterone (10nM) or serum obtained from patients with primary hyperaldosteronism (PA) with and without addition of a mineralocorticoid receptor (MR) antagonist for 24 hours, and differentiated to macrophages. We assessed the ability of these cells to produce ROS and cytokines upon re-stimulation. Changes in immunometabolism were assessed via extracellular flux measurements with Seahorse XF technology and further explored at the genome level with RNA microarray. Chromatin immunoprecipitation was performed to assess histone modifications in aldosterone-exposed cells. In vitro exposure of human monocytes with both aldosterone and PA serum induced a trained immunity phenotype characterized by augmented IL-6 and TNF-α responses, as well as ROS production to re-stimulation, an effect that was prevented by the MR antagonist spironolactone. Aldosterone-trained cells showed no differences in glycolysis or oxidative phosphorylation compared to vehicle treated cells. Instead, RNA microarray showed upregulation of the fatty acid synthesis (FAS) pathway, which we validated with qPCR. Pharmacological inhibition of FAS abolished the induction of training by aldosterone. Moreover, the aldosterone-trained phenotype was associated with enrichment of the transcriptionally-permissive histone mark H3K4me3, at the level of the promoters of central genes in the fatty acid synthesis pathway. In conclusion, aldosterone induces a form of trained immunity which is dependent on activation of the MR and induction of fatty acid synthesis. This novel pathway of immune activation uncovers potential pharmacological targets for patients with hyperaldosteronism. To translate these findings, we have recruited 15 patients with proven primary hyperaldosteronism and 15 matched patients with essential hypertension and comprehensively assessed systemic inflammation and monocyte phenotype as well as vascular wall inflammation with fluorodeoxyglucose-positron emission tomography. The results of these analyses will be available at the time of ENDO 2019. (1) van der Heijden et al. Cardiovasc Res. 2018 Jun 1;114(7):944-953. (2) Netea et al. Science. 2016 Apr 22;352(6284)

The ACUTE (Ambulance CPAP: Use, Treatment effect and economics) feasibility study: a pilot randomised controlled trial of prehospital CPAP for acute respiratory failure

Background

Acute respiratory failure (ARF) is a common and life-threatening medical emergency. Standard prehospital management involves controlled oxygen therapy and disease-specific ancillary treatments. Continuous positive airway pressure (CPAP) is a potentially beneficial alternative treatment that could be delivered by emergency medical services. However, it is uncertain whether this treatment could work effectively in United Kingdom National Health Service (NHS) ambulance services and if it represents value for money.

Methods

An individual patient randomised controlled external pilot trial will be conducted comparing prehospital CPAP to standard oxygen therapy for ARF. Adults presenting to ambulance service clinicians will be eligible if they have respiratory distress with peripheral oxygen saturation below British Thoracic Society (BTS) target levels, despite titrated supplemental oxygen. Enrolled patients will be allocated (1:1 simple randomisation) to prehospital CPAP (O_two system) or standard oxygen therapy using identical sealed boxes. Feasibility outcomes will include incidence of recruited eligible patients, number of erroneously recruited patients and proportion of cases adhering to allocation schedule and treatment, followed up at 30 days and with complete data collection. Effectiveness outcomes will comprise survival at 30 days (definitive trial primary end point), endotracheal intubation, admission to critical care, length of hospital stay, visual analogue scale (VAS) dyspnoea score, EQ-5D-5L and health care resource use at 30 days. The cost-effectiveness of CPAP, and of conducting a definitive trial, will be evaluated by updating an existing economic model. The trial aims to recruit 120 patients over 12 months from four regional ambulance hubs within the West Midlands Ambulance Service (WMAS). This sample size will allow estimation of feasibility outcomes with a precision of < 5%. Feasibility and effectiveness outcomes will be reported descriptively for the whole trial population, and each trial arm, together with their 95% confidence intervals.

Discussion

This study will determine if it is feasible, acceptable and cost-effective to undertake a full-scale trial comparing CPAP and standard oxygen treatment, delivered by ambulance service clinicians for ARF. This will inform NHS practice and prevent inappropriate prehospital CPAP adoption on the basis of limited evidence and at a potentially substantial cost.

Trial registration

ISRCTN12048261. Registered on 30 August 2017. http://www.isrctn.com/ISRCTN12048261

Analysis of tissue from products of conception and perinatal losses using QF-PCR and microarray: A three-year retrospective study resulting in an efficient protocol

OBJECTIVE

To evaluate the performance of a laboratory protocol for direct genetic analysis performed on tissues obtained from miscarriages, stillbirth and postnatal death.

METHODS

Samples were collected between July 1st, 2011 and June 30th, 2014. QF-PCR analysis was the initial test followed by aCGH analysis performed on the normal QF-PCR specimens.

RESULTS

Of the 1195 submitted specimens, a total of 1071 samples were confirmed as true fetal. The failure rate was 1.4%. Of those, 30.8% yielded abnormal results. Of the latter, 57.6% had abnormal QF-PCR and 42.4% had abnormal microarray result. Autosomal trisomies were detected in 61.2%, triploidy in 7.6%, monosomy X in 9.1%, sex-chromosome aneuploidy (apart from monosomy X) in 1.5%, molar pregnancies in 5.8% and copy number variants in 14.2% including microdeletions/microduplications and cryptic unbalanced rearrangements. The highest diagnostic yield was observed in the 1st trimester specimens at 67.6%. We confirmed that maternal age correlates with the likelihood of autosomal trisomies but not with triploidy, sex chromosome aneuploidies, molar pregnancy, or CNVs.

CONCLUSION

An efficient laboratory protocol, based on QF-PCR and aCGH of uncultured cells has replaced standard cytogenetic analysis in testing of tissue from all pregnancy losses in our center and resulted in reduced test failure rate and increased diagnostic yield.

Effect of integrating HIV and addiction care for non-engaging HIV-infected opiate-dependent patients

BACKGROUND

HIV-positive substance dependent patients contribute disproportionally to HIV morbidity and mortality as a result of poor compliance with their HIV treatment. For HIV-positive opiate-dependent patients integrating HIV and addiction care improves HIV morbidity but the effect on addiction morbidity is not known.

AIMS

This study aims to establish if integrating HIV and addiction care has a significant effect on addiction and HIV morbidity for non-engaging HIV-positive opiate-dependent patients.

METHODS

Patients attending the National Drug Treatment Centre who had disengaged from their HIV treatment in St James's Hospital were recruited to receive HIV care integrated into their methadone maintenance programme. Outcome was investigated in terms of urine toxicology (opiates, cocaine, cannabis and amphetamines); adherence to methadone; proportion receiving directly observed antiretroviral therapy; proportion HIV virally suppressed; and the CD4 cell count.

RESULTS

No significant change in substance use or methadone adherence was demonstrated in the 19 recruited participants. There was a significant increase in the proportion receiving directly observed antiretroviral therapy, and in the CD4 cell count.

CONCLUSION

Integration of HIV and addiction care optimises the physical health of non-engaging HIV-positive opiate-dependent patients with no substantial effect on their methadone maintenance programme.

BioModels: Content, Features, Functionality, and Use

BioModels is a reference repository hosting mathematical models that describe the dynamic interactions of biological components at various scales. The resource provides access to over 1,200 models described in literature and over 140,000 models automatically generated from pathway resources. Most model components are cross-linked with external resources to facilitate interoperability. A large proportion of models are manually curated to ensure reproducibility of simulation results. This tutorial presents BioModels' content, features, functionality, and usage.

Temporal lobe dysplasia: a characteristic sonographic finding in thanatophoric dysplasia

OBJECTIVE

To determine the incidence of temporal lobe dysplasia (TLD) detected on prenatal ultrasound in thanatophoric dysplasia (TD) over an 11-year period in a tertiary referral center.

METHODS

An 11-year retrospective review of perinatal autopsies from 2002 to 2013 was performed to identify cases of TD. The ultrasound images and corresponding reports of all TD cases were examined for the presence of TLD. The same set of images subsequently underwent a retrospective review by a perinatal radiologist with knowledge of the features of TLD to determine whether they could be identified.

RESULTS

Thirty-one cases of TD underwent perinatal autopsy, and prenatal ultrasound imaging was available for review in 24 (77%). Mean gestational age at diagnosis of TD was 21.3 (range, 18-36) weeks. TLD was identified and reported in 6/24 (25%) cases; all six cases occurred after 2007. Retrospective interpretation of the ultrasound images identified features of TLD in 10 additional cases. In total, 16/24 (67%) cases displayed sonographic evidence of TLD. Temporal trends showed that TLD features were present in 50% (5/10) of all TD cases between 2002 and 2006 and in 79% (11/14) of those detected between 2007 and 2013.

CONCLUSIONS

At present, the detection rate of TLD by ultrasound is low but may be increased by modified brain images that enhance visualization of the temporal lobes. Prenatal identification of TLD may help in the prenatal diagnosis of TD and thus provide more accurate prenatal counseling and guide molecular investigations to confirm the specific diagnosis of TD.

Fetal skeletal dysplasias in a tertiary care center: radiology, pathology, and molecular analysis of 112 cases

Fetal skeletal dysplasias are a heterogeneous group of rare genetic disorders, affecting approximately 2.4-4.5 of 10,000 births. We performed a retrospective review of the perinatal autopsies conducted between the years 2002-2011 at our center. The study population consisted of fetuses diagnosed with skeletal dysplasia with subsequent termination, stillbirth and live-born who died shortly after birth. Of the 2002 autopsies performed, 112 (5.6%) were diagnosed with skeletal dysplasia. These 112 cases encompassed 17 of 40 groups of Nosology 2010. The two most common Nosology groups were osteogenesis imperfecta [OI, 27/112 (24%)] and the fibroblast growth factor receptor type 3 (FGFR3) chondrodysplasias [27/112 (24%)]. The most common specific diagnoses were thanatophoric dysplasia (TD) type 1 [20 (17.9%)], and OI type 2 [20 (17.9%)]. The combined radiology, pathology, and genetic investigations and grouping the cases using Nosology 2010 resulted in a specific diagnosis in 96 of 112 cases.

Minimally invasive fetal therapy for hydropic lung masses: three different approaches and review of the literature

OBJECTIVE

To report three different antenatal therapeutic approaches for fetal lung masses associated with hydrops.

METHODS

Three prospectively followed cases are described, and all 30 previously published minimally invasive cases of fetal therapy for hydropic lung masses are reviewed.

RESULTS

Three hydropic fetuses with large intrathoracic lung masses presented at 17, 25 and 21 weeks of gestation, respectively. An aortic feeding vessel was identified in each case and thus a bronchopulmonary sequestration (BPS) was suspected. Under ultrasound guidance, the feeding vessel was successfully occluded with interstitial laser (Case 1), radiofrequency ablation (RFA) (Case 2) and thrombogenic coil embolization (Case 3). Complete (Cases 1 and 2) or partial (Case 3) resolution of the lung mass and hydrops was observed. A healthy infant was born at term after laser therapy (Case 1), and the involved lung lobe was resected on day 2 of postnatal life. In Case 2, hydrops resolved completely following RFA, but an iatrogenic congenital diaphragmatic hernia and abdominal wall defect became apparent 4 weeks later. The neonate died from sepsis following spontaneous preterm labor at 33 weeks. In Case 3, despite technical success in complete vascular occlusion with coils, a stillbirth ensued 2 days after embolization.

CONCLUSIONS

The prognosis of large microcystic or echogenic fetal chest masses associated with hydrops is dismal. This has prompted attempts at treatment by open fetal surgery, with mixed results, high risk of premature labor and consequences for future pregnancies. We have demonstrated the possibility of improved outcome following ultrasound-guided laser ablation of the systemic arterial supply. Despite technical success, RFA and coil embolization led to procedure-related complications and need further evaluation.

Placental hyperinflation and the risk of adverse perinatal outcome

OBJECTIVES

To determine the pathological basis and clinical associations of excessively thick placentae observed at second-trimester ultrasound examination.

METHODS

In a retrospective cohort of 19 singleton high-risk second-trimester pregnancies noted to have a placental length-to-maximum thickness ratio ≤ 2.0, maximum sonographic placental thickness was correlated with clinical outcome, maximum placental thickness after delivery and placental pathological findings. Results were compared with those of an intermediate group of 21 high-risk pregnancies with normal placental dimensions and a control group of 18 low-risk pregnancies also with normal placental dimensions. Increased maximum placental thickness (> 28 mm) and abnormal placental deflation following delivery (pathology - sonography difference in maximum placental thickness < -2 mm) were defined by the upper and lower quartile values, respectively, in the control group.

RESULTS

The study group exhibited significantly more adverse outcomes and gross pathological placental features compared with both intermediate and control groups. Despite increased sonographic maximum placental thickness in the study group (median, 55 (range, 40-75) mm compared with both the intermediate group (median, 27 (range, 22-41) mm, P < 0.0001) and the control group (median 26 (range, 23-36) mm, P < 0.0001)), all three groups had similar maximal placental thickness following delivery (study group: median, 24 (range, 10-50) mm vs intermediate group: median, 27 (range, 15-40) mm, P = 0.82 and vs control group: median, 28.5 (range, 18-44), P = 0.42). Pathology-sonography difference in maximum placental thickness in the study group (median, -30 (range, -42 to 0) mm) was significantly greater than that in either the intermediate (median, -2 (range, -11 to 9) mm, P < 0.0001) or the control (median, 1.5 (range, -10 to 18) mm, P < 0.0001) group and was significantly associated with abnormal development of the gas-exchanging placental villi (distal villous hypoplasia) (P = 0.0001).

CONCLUSIONS

Increased second-trimester sonographic maximum placental thickness represents a pathological finding associated with severe adverse perinatal outcome. This observation is due to overinflation of the intervillous space by maternal blood rather than to adaptive formation of functional placental tissue.

Leptin is differentially expressed and epigenetically regulated across monochorionic twin placenta with discordant fetal growth

Severely growth-discordant monochorionic (MC) twins offer a unique opportunity to study fetal and placental growth based on a similar genetic background and maternal host environment where the healthy twin serves as an ideal control. Differences in development of MC twins may therefore be due to differential epigenetic regulation of genes involved in placental development and function. Growth-discordant twins are known for abnormal angio-architecture in the placenta of the smaller twin. Since the reasons for this phenotype are mostly unknown this study was aimed to investigate the expression and regulation of genes known to be involved in angiogenesis. We studied 10 severely growth-discordant MC twin placentas (birthweight difference ≥20%) without twin-twin-transfusion syndrome and 5 growth-concordant MC twin placentas. Growth-discordant twin placentas were phenotyped by histology. Placental mRNA expression of 88 angiogenesis-related genes was measured by PCR array. ELISA assay and immunohistochemistry were used to confirm PCR results. EpiTYPTER for DNA methylation was used to determine if methylation ratios were responsible for differential gene expression. The PCR array analysis showed significant mRNA up-regulation in the placental share of the smaller twin for several genes. These included leptin (24.6-fold, P = 0.017), fms-like tyrosine kinase 1 (Flt1, 2.4-fold, P = 0.016) and Endoglin (Eng, 1.86-fold, P = 0.078). None of the other 84 angiogenesis-related genes showed significant differences. ELISA confirmed significantly increased leptin protein expression (49.22 versus 11.03 pg/ml, P = 0.049) in the smaller twin of the discordant growth cohort. Leptin expression in smaller twins' placentas was associated with elevated DNA methylation of the leptin promotor region suggesting the inhibition of binding of a transcriptional activator/inhibitor in that region. We attempted to overcome the limitation of sample size by careful patient selection. We minimized any bias in placental sampling by random sampling from two different sites and by avoiding sampling from areas with grossly visible abnormalities using a standardized sampling protocol. In conclusion, the smaller twin's placenta is characterized by differentially increased gene expressions for Flt1 and Eng mRNA that may be causally associated with the villous pathology driven by abnormal feto-placental angiogenesis. The substantial up-regulation of leptin mRNA may be epigenetically conferred and relevant to the post-natal risk of metabolic syndrome in intrauterine growth restriction offspring with placental pathology. Growth-discordant MC twins offer unique insights into the epigenetic basis of perinatal programming.