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Important: please update your RDS app to version 4.7.3 Details with newsletter below.

Please update your RDS app to v4.7.3

We asked you in January to update to v4.7.2.  After the deployment planned for 27th February, this new update will be needed to ensure that you are able to download RDS toolkits even when the RDS website is not available. We will wait until as many users as possible have downloaded the new version before switching off the old system for app downloads and moving entirely to the new approach.

To check your current RDS version, click on the three dots bottom right of the RDS app screen. This takes you to a “More” page where you will see the version number. 

To update to the latest release:

 On iPhones – go to the Apple store, click on your profile icon top right, scroll down to see the apps waiting to be updated and update the RDS app.

On Android phones – these can vary, but try going to the Google Play store, click on your profile icon top right, click on “Manage apps and device”, select and update the RDS app.

Right Decision Service newsletter: February 2025

Welcome to the February 2025 update from the RDS team

1.     Next release of RDS

 

A new release of RDS is planned (subject to outcomes of current testing) for week beginning 24th February. This will deliver:

 

  • Fixes to mitigate the recurring glitches with the RDS admin area and the occasional brief user interface outages which have arisen following implementation of the new distributed technology infrastructure in December 2024.

 

  • Capability to embed content from Google calendar, Google Maps, Daily Motion, Twitter feeds, Microsoft Stream into RDS pages.

 

  • Capability to include simple multiplication in RDS calculators.

 

The release will also incorporate a number of small fixes, including:

  • Exporting of form within Medicines Sick Day Guidance in polypharmacy toolkit
  • Links to redundant content appearing in search in some RDS toolkits
  • Inclusion of accordion headers alongside accordion text in search result snippets.
  • Feedback form on mobile app.
  • Internal links on mobile app version of benzo tapering tool

 

We will let you know when the date and time for the new release are confirmed.

 

2.     New RDS developments

There is now the capability to publish toolkits on the web with left hand side navigation rather than tiles on the homepage. To use this feature, turn on the “Toggle navigation panel” option at the top of the Page settings menu at toolkit homepage level – see below. Please note that publication to downloadable mobile app for this type of navigation is still under development.

The Benzodiazepine tapering tool is now available as part of the RDS toolkit for the national benzodiazepine prescribing guidance developed by the Scottish Government Effective Prescribing team. The tool uses this national guidance developed with a wide-ranging multidisciplinary group. This should be used in combination with professional judgement and an understanding of the needs of the individual patient.

3.     Archiving and version control and new RDS Search and Browse interface

Due to the intensive work Tactuum has had to undertake on the new technology infrastructure has pushed back the delivery dates again and some new requirements have come out of the recent user acceptance testing. It now looks likely to be an April release for the search and browse interface. The archiving and version control functionality may be released earlier. We’ll keep you posted.

4.     Statistics

At the end of January, Olivia completed the generation of the latest set of usage statistics for all RDS toolkits. If you would like a copy of the stats for your toolkit, please contact Olivia.graham@nhs.scot .

 

5.     Review of content past its review date

We have now generated reports of all RDS toolkit content that has exceeded its review date by 6 months or more. We will be in touch later this month with toolkit owners and editors to agree the plan for updating or withdrawing out of date content.

 

6.     Toolkits in development

Some important toolkits in development by the RDS team include:

  • National CVD prevention pathways – due for release end of March 2025.
  • National respiratory pathways, optimal cancer diagnostic pathways and cancer prehabilitation pathways from the Centre for Sustainable Delivery. We will shortly start work on the national cancer referral pathways, first version due for release via RDS around end of June 2025.
  • HIS Quality of Care Review toolkit – currently in final stages of quality assurance.

 

The RDS team and other information scientists in HIS have also been producing evidence summaries for the Scottish Government Realistic Medicine team, to inform development of national guidance around Procedures of Limited Clinical Value. This guidance will in due course be translated into an RDS toolkit.

 

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

  • Friday 28th February 12-1 pm
  • Tuesday 11th March 4-5 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

 

 

Estimated Due Date (EDD) Ultrasound Scan (501)

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

EDD should be calculated from the first scan ≥ 11+ 2 weeks gestational age (≥ 45mm).

If the initial scan is performed < 11+2 weeks gestation, the patient should have a return appointment at approximately 12-13 weeks gestation to perform optimal dating +/- NT measurements.
(Refer to Screening / Non-screening Pathways)

Upper and lower limbs must be assessed as well as cranial anatomy

As adapted from Chudleigh, Loughna & Evans (2011) from BMUS.

Parameter 

Parameter used for establishing EDD

Down’s Syndrome Screening method

CRL < 45.0mm

Unable to date. Re-scan at 12-13 weeks gestation

N/A

CRL 45.0mm – 84.0mm

CRL

First Trimester CUBS 

CRL >84mm  and HC< 101.0mm

Unable to date.  Re-scan ≥ 14+2 weeks gestation

No screening until EDD confirmed

HC ≥ 101.0mm – 172.0mm

HC

Second Trimester Bloods only (AFP)

Recommended criteria for measurement of CRL for pregnancy dating (UKNSC, 2015):

CRL DETAIL TO BE DEMONSTRATED
MIDLINE SECTION
  • Sagittal section of the fetus with the head in line with the full length of the body
  • Echogenic tip of the nose
  • Rectangular shape of the palate
  • Translucent Diencephalon
  • CRL axis should be between 0-30 degrees to horizontal
  • Clearly defined crown and rump 
POSITION
  • Pocket of fluid, at least equivalent in size to the width of the palate, should be visible between the fetal chin and chest 
  • Fetal palate angle should be 30º to 60º relative to the horizontal 
  • Nasal tip should be level or above the anterior abdominal wall 
MAGNIFICATION
  • Entire CRL section should fill over 60% of the screen 
CALIPER PLACEMENT
  • Correct calliper placement on outer borders of crown and rump
  • Longest length of the fetus should be measured
IMAGE ARCHIVING
  • The CRL should be measured at least twice and the maximum measurement that meets the criteria should be recorded 
  • The image demonstrating the measured CRL which has been reported should be archived

The HC should be calculated using the recommended values of Altman and Chitty as per BMUS recommendations.

Technique for calculation of HC:

A cross-sectional view of the fetal head at the level of the ventricles should be obtained. The image should have the midline echo lying as close as possible to the horizontal plane.

The following landmarks should be identified and the image frozen:

  • rugby ball shape;
  • centrally positioned, continuous midline echo broken at one third of its length by the cavum septum pellucidum;
  • anterior walls of the lateral ventricles centrally placed around the midline;
  • the choroid plexus should be visible within the posterior horn of the ventricle in the distal hemisphere.
  • Callipers should be placed on the outer border of the occipital and frontal bones as close as possible to the midline across the longest part of the skull.

If HC measurements cannot be made then EDD should be calculated using the femur length (FL)

Technique for calculation of FL:

The image should be obtained with the femur lying as close as possible to the horizontal plane. The full length of the bone should be visualised with soft tissue visible at both ends. Calipers should be placed at the centre of the ‘U’-shape at each end of the bone.

After 25 completed weeks the patient will be classed as ‘LATE BOOKER'.

All three measurement parameters [HC, AC and FL] should be obtained.

An EDD will be calculated from the HC measurement and entered on Badgernet. On the ultrasound report page type in comments ‘EDD based on HC >25 weeks GA’ and create a LATE BOOKER alert.

If there is discrepancy in the sizes between the fetuses, the EDD should be calculated from the largest fetus, using the criteria above.

Gestational age may be assessed from measurements of the mean sac diameter (MSD). This is calculated from the maximal diameters of the gestation sac (in mm) in the longitudinal and transverse views on transvaginal scan. The Mean gestation sac volume should be calculated where a transvaginal examination is declined using the full bladder technique.

An EDD should only be generated once a live embryo or fetus has been identified measuring ≥ 45mm.

Editorial Information

Last reviewed: 31/05/2022

Next review date: 31/05/2026

Author(s): Donna Maria Bean.

Version: 2

Approved By: Obstetrics Clinical Governance Group

Document Id: 501

References

Altman DG & Chitty LS (1997). New charts for ultrasound dating of pregnancy. Ultrasound Obstet Gynecol 10:174-91

Antenatal Care: Routine care for the pregnant healthy woman. National Institute of Clinical Excellence (NICE) Guildeline.

Chudleigh, T., Loughna, P and Evans, T. (2011). A practical solution to combining dating and screening for down’s syndrome. Education & Training 1:154-71

Fetal Anomaly Screening Programme Handbook for Ultrasound Practitioners. UKNSC  April 2015.

Fetal Size and Dating:Charts Recommended for Clinical Obstetric Practice. BMUS, Jan 2008

Guidelines for Professional Working Standards. Ultrasound Practice. United Kingdom Association of Sonographers. October 2008