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Right Decision Service newsletter: October 2024

Welcome to the Right Decision Service (RDS) newsletter for October 2024.

1.Contingency arrangements for RDS outages

Development of the contingency solutions to maximise RDS resilience and minimise risk of future outages is in progress, aiming for completion by Christmas. As a reminder, these contingency arrangements  are:

  • Optimising mobile app build process
  • Mobile app always to be downloadable.
  • Serialising builds to mobile app; separate mobile app build from other editorial and end-user processes
  • Load balancing – provides failover (also enables separation of editorial processes from other processes to improve performance.)

 

In the meantime, a gentle reminder to encourage users to download essential clinical toolkits to their mobile devices so that there is an offline version always available.

 

2. New deployment with improvements.

A new scheduled deployment with minor improvements drawn from support tickets, externally funded projects, information related to outages, and feature requests will take place in early December. Key improvements planned are:

  • Deep-linking to individual toolkits within the RDS mobile app. Each toolkit will now have its own direct URL and QR code, both accessible from the app. These can be used to download the toolkit directly where users already have the RDS app installed. If the user does not yet have the RDS app installed, they will be taken to the app store to install the app and immediately afterwards the toolkit will automatically open and download. Note that this will go live a few days later than the improvements below due to the need to link up the mobile front end to the changes in the content management system.
  • Introducing an Announcement Header field to replace the hardcoded "Announcements and latest updates" text. This will enable users to see at a glance the focus of new announcements.
  • Automated daily emptying of the recycling bin (with a 30 day rolling grace period)  in the content management system. A bug preventing complete emptying of the recycling bin contributed to one of the outages earlier this year.
  • Supporting multiple passcodes (ticket 6079)
  • Expanding accordion section to show location of a search result rather than requiring user coming from a search result to manually open all sections and search again for the term.
  • Displaying first accordion section Content text as a snippet on the search results page as a fallback if default/main content is not provided
  • Displaying the context of each search result in the form of a link to the relevant parent tool/section. This will help users to choose which search result is most likely to be appropriate for their needs.
  • As part of release of the new national benzodiazepine quality prescribing guidance toolkit sponsored by Scottish Government Effective Prescribing and Therapeutics, a digital tool to support creation of benzodiazepine tapering/withdrawal schedules.

We are also seeking approval to use the NHS Scotland logo and title for the RDS app on the app stores to help with audience engagement and clarity around the provenance of RDS.

3. RDS Search, Browse and Archive/Version control enhancements

We are still hopeful that user acceptance testing for at least the Search and browse enhancements can take place before Christmas. Thank you for your patience and understanding in waiting for these improvements. Timescales have been pushed back by old app migration challenges, work to address outages, and most recently implementing the contingency arrangements.

4. Support tickets

We are aware that there continue to be some issues around a number of RDS support tickets, in part due to constraints around visibility for the RDS team of the tickets in the existing  support portal. We are investigating the potential to move to a new support ticket requesting system from early in the new year. We will organise the proposed webinar around support ticket processes once we have confirmed the way forward with the system.

Table formatting

There is a known issue with alterations in formatting of some RDS tables which seems to have arisen as a result of the 17 October deployment. Tactuum is working on a fix and on implementing additional regression testing to prevent this issue recurring.

5. New RDS toolkits

Recently launched toolkits include:

NHS Lothian Infectious Diseases

Scottish Health Technologies Group – Technology Assessment recommendations

NHS Tayside Anaesthetics and Critical Care projects – an innovative toolkit which uses PowerAutomate to manage review and response to proposals for improvement projects.

If you would like to promote one of your new toolkits through this newsletter, please contact ann.wales3@nhs.scot

A number of toolkits are expected to go live before Christmas, including:

  • Focus on dementia
  • Highland Council Getting it Right for Every Child
  • Dumfries and Galloway Adult Support and Protection procedures
  • National Waiting Well toolkit
  • Fertility Scotland National Network
  • NHS Lothian postural care for care homes

6.Sign up to RDS Editors Teams channel

We have had a good response to the recent invitation to sign up to the new Teams channel for RDS editors. This provides a forum for editors to share learning, ideas and questions and we hope to hold regular webinars on topics of interest.  The RDS team is in the process of joining participants to the channel and we’d encourage all editors to take part, using the registration form – available in Providers section of the RDS Learning and Support area.

 

7. Evaluation projects

The RDS team has worked with colleagues in NHS Grampian and the Digital Health & Care Innovation Centre to evaluate the impact of the Prevent the progress of diabetes web and mobile app in a small-scale pilot project. This app provides access to local and national resources and services targeted at people with prediabetes, a history of gestational diabetes, or candidates for remission. After just 8 weeks of using the app, 94% of patients reported increased their knowledge and understanding of diabetes, and 88% said it had increased their confidence and motivation to make lifestyle changes, highlighting specific behaviour changes. The learning from this project is informing development of a service model based on tailored support for patient groups with, high, medium and low digital self-efficacy.

Please contact ann.wales3@nhs.scot if you would like to know more about this project.

  1. Training sessions for new editors (also serve as refresher sessions for existing editors) will take place on the following dates:

  • Friday 29th November 3-4 pm
  • Thursday 5 December 3.30 -4.30 pm

To book a place, please contact Olivia.graham@nhs.scot, providing your name, organisation, job role, and level of experience with RDS editing (none, a little, moderate, extensive.)

 

To invite colleagues to sign up to receive this newsletter, please signpost them to the registration form  - also available in End-user and Provider sections of the RDS Learning and Support area.   If you have any questions about the content of this newsletter, please contact his.decisionsupport@nhs.scot  If you would prefer not to receive future newsletters, please email Olivia.graham@nhs.scot and ask to be removed from the circulation list.

With kind regards

 

Right Decision Service team

Healthcare Improvement Scotland

 

The Right Decision Service:  the national decision support platform for Scotland’s health and care

Website: https://rightdecisions.scot.nhs.uk    Mobile app download:  Apple  Android

 

 

Twin Pregnancy Ultrasound Guideline (330)

Please report any inaccuracies or issues with this guideline using our online form

Gestational Age, Chorionicity and Amnionicity

Women should be offered a first trimester USS (< 14+0 weeks) to estimate gestational age and determine chorionicity and amnionicity.

Chorionicity and amnionicity should be determined by the number of placental masses, the presence of amniotic membranes and membrane thickness, the lambda or T-sign.

Clear nomenclature should be assigned e.g inferior and superior, or left and right, in a twin or triplet pregnancy to ensure consistency throughout pregnancy.

If a multiple pregnancy presents after 14+0 weeks then determination of chorionicity and amnionicity could also take into account discordant fetal sex if required.

If TAUSS views are poor because of a retroverted uterus or a high BMI, use a transvaginal ultrasound scan to determine chorionicity and amnionicity.

The largest baby should be used to calculate the estimated date of delivery for the pregnancy.

A photographic record should be placed in the patient’s hospital held records documenting the ultrasound appearance of the membrane attachment to the placenta and an electronic / hard drive record stored. Chorionicity must be checked by senior sonographer

If there is still doubt about the chorionicity, the woman should be referred to medical staff for chorionicity assessment without delay.

Following this if there is still doubt, the pregnancy should be managed as monochorionic until proved otherwise.

Screening

Referral should be made for counselling for antenatal screening for combined trisomy (21,18,13) following the diagnosis of a twin pregnancy (fetal medicine at QEUH, Day Care counselling midwife PRM, Screening midwife Clyde). This should ideally be prior to the 11+2 to 14+1 week scan.

The test of choice for twin pregnancies is first trimester combined screening. Every opportunity must be made to maximise the offer of first trimester combined screening. Chance results to be reported are:

  • a term chance of T21 and a term chance of T18/T13
  • a term chance of T21 only
  • a term chance of T18/T13 only

First trimester combined screening will be reported in a dichorionic twin pregnancy as a chance for each fetus whereas in a monochorionic twin pregnancy it will be reported as a chance per pregnancy.

Women who ‘miss’ or have unsuccessful first trimester screening for aneuploidy should be offered second trimester screening for T21. Chance results are reported as a pregnancy related chance that is not fetal specific.

Monochorionic Twins

Fetal ultrasound assessment should be performed every two weeks in uncomplicated monochorionic twins from 16+0 weeks onwards until delivery.

Scans at 16 and 20 weeks (detailed anomaly scan) should be performed by a medical sonographer. The detailed fetal anomaly scan should include extended cardiac views (5 standard views).

At every ultrasound, the following should be assessed and recorded:

  • liquor volume (LV) should be assessed in each sac and deepest vertical pool (DVP)
  • Umbilical artery pulsatility index (UAPI)*
  • Fetal bladders should be assessed.
  • Middle Cerebral Artery Peak Systolic Velocity (MCA PSV)

*See Umbilical Artery Pulsatility Index Chart

Increase the frequency of diagnostic monitoring for TTTS in the woman’s 2nd and 3rd trimester to at least weekly if there are concerns about differences between the babies’ amniotic fluid level (a difference in DVP depth of 4cm or more). Include Doppler assessment of the umbilical artery flow for each baby.

Refer for medical scan if LV DVP>8 cm or <2cm before 20 weeks or LV DVP >10cm or <2cm after 20 weeks. If abnormality confirmed discussion with fetal medicine at QEUH is indicated.

Staging of Twin-to-twin transfusion syndrome (TTTS)

Stage Description

I

II

III

IV

V

Poly/oligohydramnios with bladder of the donor still visible

Bladder of the donor no longer visible

Presence of either absent or reverse end-diastolic velocity of the umbilical artery, reverse flow in either twin

Hydrops in either twin

Demise of one or both twins prior to surgery

From 16+0 weeks fetal biometry (HC, AC and FL) should be assessed and abdominal circumference (AC) and Estimated fetal weight (EFW) recorded for each twin. The discordance in EFW should be calculated and documented in monochorionic twins at each visit:

([EFW larger fetus − EFW smaller fetus] ÷ EFW larger fetus) × 100

Increase diagnostic monitoring in the 2nd and 3rd trimesters to at least weekly, and include Doppler assessment of the umbilical artery flow for each baby, if there is an EFW discordance of 20% or more and/or the EFW of any of the babies is below the 10th centile for gestational age.

Refer women with a monochorionic twin pregnancy to a tertiary level fetal medicine centre if there is an EFW discordance of 25% or more and the EFW of either of the babies is below the 10th centile for gestational age because this is a clinically important indicator of selective fetal growth restriction.

Selective intrauterine growth restriction (growth discordance of >20%). Approximately 10-15 % of MCDA twins

Stage Description

I

II

III

Growth discordance but positive diastolic velocities in both fetal umbilical arteries.

Growth discordance with absent or reversed end-diastolic velocities (AREDV) in one or both fetuses.

Growth discordance with cyclical umbilical artery diastolic waveforms (positive followed by absent then reversed end-diastolic flow in a cyclical pattern over several minutes [intermittent AREDV; iAREDV]).

Offer weekly USS monitoring for TAPS from 16 weeks of pregnancy using middle cerebral artery peak systolic velocity (MCA-PSV) to women who pregnancies are complicated by:

  • feto-fetal transfusion syndrome that has been treated by fetoscopic laser therapy or
  • selective fetal growth restriction (defined by an EFW discordance of 25% or more and an EFW of any of the babies below the 10th centile for gestational age)

Aim for delivery between 36+0 and 36+6 for uncomplicated MCDA twins after which point continuing the pregnancy increases the risk of fetal death

For monochorionic monoamniotic twins birth should be planned between 32+0 and 33+6

Dichorionic Twins

Fetal anomaly scan can be performed by sonographer if there are no other obstetric reasons for a medical FAS.

Growth USS should be performed every 4 weeks from 24 weeks onwards. Estimated fetal weight, umbilical artery PI and deepest vertical pool of liquor should be measured at each visit.

Fetal weight discordance should be calculated for dichorionic twins:

([EFW larger fetus − EFW smaller fetus] ÷ EFW larger fetus) × 100

Increase monitoring in 2nd and 3rd trimesters to at least weekly, and include Doppler assessment of the umbilical artery flow for each baby if there is EFW discordance of 20% or more and/or the EFW of any of the babies is below the 10th centile for gestational age.

Refer women with a dichorionic twin pregnancy to a tertiary level fetal medicine centre if there is an EFW discordance of 25% or more and the EFW of any of the babies is below the 10th centile for gestational age because this is a clinically important indicator of selective fetal growth restriction.

Aim for delivery between 37+0 and 37+6 for uncomplicated DCDA twins as after this point continuing the pregnancy increases the risk of fetal death.

Appendix: Umbilical Artery Pulsatility Index (UAPI) Reference Chart

> 95th percentile is abnormal

Appendix: MONOCHORIONIC DIAMNIOTIC TWINS – antenatal appointments

(File in notes)

Monochorionic diamniotic twins - antenatal appointments - pdf

Appendix: DICHORIONIC DIAMNIOTIC TWINS –antenatal appointments

(File in notes)

Dichorionic diamniotic twins - antenatal appointments - pdf

Editorial Information

Last reviewed: 24/10/2023

Next review date: 31/10/2028

Author(s): Victoria Watson ST7 PRM, Donna Bean, Lead Sonographer Obstetrics and Gynaecology.

Version: 3

Approved By: Maternity Clinical Governance Group

Document Id: 330

References
  1. NICE [NG137. Twin and triplet pregnancy. 2019.
  2. Khalil A. ISUOG Practice Guidelines: role of ultrasound in twin pregnancy. Ultrasound in Obstetrics and Gynaecology. ISUOG. November 2015.
  3. NHS Fetal Anomaly Screening Programme (FASP). Public Health England. September 2019.