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  6. 1st Trimester Screening for Trisomy 21 (T21), Trisomy 18 (T18), Trisomy 13 (T13) in Singleton pregnancies: Nuchal Translucency (NT) Scan (499)
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Right Decision Service newsletter: April 2024

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

Issues with RDS and Umbraco access

Tactuum has been working hard to address the issues experienced during the last week. They have identified a series of three mitigation measures and put the first of these in place on Friday 3rd May.  If this does not resolve the problems, the second mitigation will be actioned, and then the third if necessary.

Please keep a lookout for any slowing down of the system or getting locked out. Please email myself, mbuchner@tactuum.com and onivarova@tactuum.com if you experience any problems, and also please raise an urgent support ticket via the Support Portal.

Thank you for your patience and understanding while we achieve a full resolution.

Promotion and communication resources

A rotating carousel presenting some of the key RDS tools and capabilities, and an editable slideset, are now available in the Resources for RDS providers section of the Learning and Support toolkit.

Redesign and improvements to RDS

The redesign of RDS Search and Browse is still on-track for delivery by mid-June 2024. We then plan to have a 3-week user acceptance testing phase before release to live. All editors and toolkit owners on this mailing list will be invited to participate in the UAT.

The archiving and version control functionality is also progressing well and we will advise on timescales for user acceptance testing shortly.

Tactuum is also progressing with the deep linking to individual toolkits within the mobile RDS app. There are several unknowns around the time and effort required for this work, which will only become clear as the work progresses. So we need to be careful to protect budget for this purpose.

New feature requests

These have all been compiled and effort estimated. Once the redesign work is complete, these will be prioritised in line with the remaining budget. We expect this to take place around late June.

Evaluation

Many thanks to those of you completed the value and impact survey we distributed in February. Here are some key findings from the 65 responses we received.

Figure 1: Impact of RDS on direct delivery of care

Key figures

  • 93% say that RDS has improved evidence-informed practice (high impact 62%; some impact 31%)
  • 91% report that RDS has improved consistency in practice (high impact 65%, some impact 26%)
  • 85% say that RDS has improved patient safety (high impact 59%, some impact 26%)
  • Although shared decision-making tools are only a recent addition to RDS, and only represent a small proportion of the current toolset, 85% of respondents still said that RDS had delivered impact in this area (53% high impact, 32% some impact.) 92% anticipate that RDS will deliver impact on shared decision-making in future and 85% believe it will improve delivery of personalised care in future.

Figure 2 shows RDS impact to date on delivery of health and care services

 

Key figures

These data show how RDS is already contributing to NHS reform priorities and supporting delivery of more sustainable care.

Saving time and money

  • RDS clearly has a strong impact on saving practitioner time, with 90% of respondents reporting that this is the case. 65% say it has a high impact; 25% say it has some impact on time-saving.
  • It supports devolved decision-making across the multi-professional team (85% of respondents)
  • 76% of respondents confirm that it saves money compared, for example, to investing in commercial apps (54% high impact; 22% some impact.)
  • 72% believe it has impacted already on saving money and reducing waste in the way services are delivered – e.g. reducing costs of referral management, prescribing, admissions.

Quality assurance and governance

  • RDS leads are clear that RDS has improved local governance of guidelines, with 87% confirming that this is the case. (62% high impact; 25% some impact.)

Service innovation and workforce development

  • RDS is a major driver for service innovation and improvement (83% of respondents) and has impacted significantly on workforce knowledge and skills (92% of respondents – 66% high impact; 26% some impact).

New toolkits

A few examples of toolkits published to live in the last month:

Toolkits in development

Some of the toolkits the RDS team is currently working on:

  • SARCS (Sexual Assault Response Coordination Service)
  • Staffing method framework – Care Inspectorate.
  • SIGN 171 - Diabetes in pregnancy
  • SIGN 158 – British Guideline on Management of Asthma. Selected sections will be incorporated into the RDS, and complemented by a new chronic asthma pathway being developed by SIGN, British Thoracic Society and NICE.
  • Clinical pathways from NHS Fife and NHS Lanarkshire

Please contact his.decisionsupport@nhs.scot if you would like to learn more about a toolkit. The RDS team will put you in touch with the relevant toolkit lead.

Quality audit of RDS toolkits

Thanks to all of you who have responded to the retrospective quality audit survey and to the follow up questions.  We still have some following up to do, and to work with owners of a further 23 toolkits to complete responses. An interim report is being presented to the HIS Quality and Performance Committee.

Implementation projects

Eight clinical services and two public library services are undertaking tests of change to implement the Being a partner in my care app. This app aims to support patients and the public to become active participants in Realistic Medicine. It has a strong focus on personalised, person-centred care and a library of shared decision aids, as well as simple explanations and videoclips to help the public to understand the aims of Realistic Medicine.  The tests of change will inform guidance and an implementation model around wider adoption and spread of the app.

With kind regards

Right Decision Service team

Healthcare Improvement Scotland

1st Trimester Screening for Trisomy 21 (T21), Trisomy 18 (T18), Trisomy 13 (T13) in Singleton pregnancies: Nuchal Translucency (NT) Scan (499)

Warning

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

Appointments for a dating scan including 1st trimester screening for Down’s, Edwards’ and Patau’s Syndrome (NT measurements) should be no less than 25 minutes. This should include time to get “on and off the couch”, time to perform the ultrasound examination and time to complete the report.

All Sonographers performing NT measurements must be appropriately trained and accredited and their results subjected to rigorous audit and performance management. To assure continuing satisfactory performance each Sonographer must perform a minimum of 25 nuchal translucency measurements every 6 months and have DQASS ‘Green’ or ‘Amber’ flag status.

The ultrasound equipment used must meet NSC FASP specifications. It should have a cineloop function and calliper precision to one decimal point i.e. 0.1mm. Operators should be aware of and adhere to BMUS guidelines for safe use of ultrasound including exposure times.

The screening period is between 11+2 to 14+1 weeks gestation. The scan will be targeted at a gestation of approx 12 weeks. The scan can be performed by the transabdominal or transvaginal route.

Consent

Sonographers must ensure formal consent has been obtained. Check the details of the booking on the ‘antenatal assessment’ tab on Badger net under ‘screening and scans offered/accepted or declined'.

Women can chose to have screening for T21 syndrome only or to have screening for T21, T18 & T13. It is not possible to have screening for T18 and/or T13 without screening for T21.

Prior to beginning scan, give a brief explanation of the scan, including limitations and obtain verbal consent to continue.

If consent for 1st trimester screening is not obtained a “dating” scan only should be performed. The Sonographer should also advise that if an increased NT ≥ 3.5mm is detected, this can be indicative of a structural abnormality and would require referral to a Medical Sonographer.

The Ultrasound Examination

Where both dating and 1st trimester screening are requested and the CRL is between 45.0 and 84.0mm, the pregnancy should be dated using the CRL measurement.

Criteria for measurement of the fetal crown rump length (CRL) as part of the combined 1st trimester screening programme

The CRL range should be between 45.0 and 84.0 mm.

The magnification of the fetus should be as large as possible clearly demonstrating the entire crown-rump length.

A midline sagittal section of the whole fetus should be obtained with the fetus horizontal on the screen, either supine or prone. The fetus should be in a neutral position with fluid visible between the fetal chin and chest, neither hyper extended nor flexed.

The best of three measurements should be taken. Linear callipers should be used to measure the maximum un-flexed length. Intersection of the callipers (+) should be placed on the outer margin of the skin borders of the CRL. Two images of the measured CRL must be retained, one for the patient record and one for audit purposes.

If the CRL is < 45.0mm re-appoint the patient within the 11+2 – 14+1 weeks screening window.

If the CRL is > 84.0mm arrange appointment for 2nd trimester biochemistry screening and date pregnancy using Head Circumference (HC).

The NT Measurement

The NT measurement should only be performed if a CRL measurement, which meets the recommended NHS FASP criteria for CRL has been obtained.

Criteria for measurement of the fetal nuchal translucency (NT) measurement

A midline sagittal section of the fetus should be obtained. The fetus should be horizontal on the screen, either supine or prone.

Care must be taken to distinguish between fetal skin and amnion. The fetus should be in a neutral position.

The image should be magnified, such that only the fetal head and upper thorax occupy the whole screen. In magnifying the image (pre- or post-zoom) it is important to turn down the gain.

The widest part of the translucency must always be measured. Measurements should be taken with the horizontal lines of the callipers placed ON the lines that define the NT thickness.

During the scan more than one measurement must be taken and the maximum one which meets all the criteria should be recorded. Two images of this measured NT should be retained, one for the patient record, one for audit purposes.

If the NT measurement is ≥ 3.5mm, perform combined screening test and follow pathway for raised nuchal translucency (NT) ≥ 3.5mm

Too early/late/unable to obtain measurements

Too Early: CRL measurement <45.0mm – re-appoint at appropriate gestation.

Too late: CRL measurement >84.0mm – arrange appointment for 2nd trimester biochemistry (≥ 15+0 weeks) screening and date pregnancy using Head Circumference (HC).

Unable to obtain measurements – offer a 2nd attempt. This second attempt at screening should be on the same day.

If unable to obtain measurements after two attempts, explain limitations of scan and record on report. Arrange 2nd trimester dating scan to coincide with biochemistry appointment.

Ultrasound Images

One set of paired CRL and NT images to be inserted into brown image envelope in patient notes, one set to be kept aside for audit purposes.

Ultrasound Report

The Ultrasound report should be documented on Badgernet under ‘Key Notes – New Ultrasound Note’. Ensure all appropriate fields are filled including the authorization box (your digital signature) for the report to be valid.

If unable to obtain NT measurements indicate reason for failed attempt i.e. poor views due to fetal position. If patient to be re-appointed for 2nd trimester screening enter suggested date.  

Medical Genetics Form (Appendix A)

Attach a patient label, with name, address, DOB and CHI number to the Medical Genetics First Trimester Combined Ultrasound and Biochemical (CUB) Screening form.

Enter the following data:

  • Hospital
  • Consultant
  • Maternal Weight
  • Number of Fetuses
  • Chorionicity if multiple pregnancy
  • Maternal Family Origin

Indicate YES or NO for the following categories:

  • Screening required – Down’s Syndrome T21
  • Screening required – Edwards’ Syndrome T18 and Patau’s Syndrome T13
  • Current Smoker
  • Previous Trisomy Pregnancy
  • IDDM

Complete the Ultrasound Details section;

  • Date of scan
  • Estimated date of delivery
  • CRL (mm)
  • NT (mm)
  • Ultrasonographer code

If assisted conception pregnancy, record all relevant details in the Assisted Conception section

“Date of sample” and “Sample taken by” fields to be entered by the Midwife/HCSW who performs the venipuncture.

Medical Genetics form to be passed to the Midwife/HCSW for completion and sent together with the biochemistry sample to Medical Genetics Labs.

Appendix A - Medical Genetics Form

Medical Genetics, First Trimester Combined Ultrasound and Biochemical (CUB) Screening Form.

 

Editorial Information

Last reviewed: 03/05/2024

Next review date: 04/05/2028

Author(s): Donna Bean.

Version: 3

Co-Author(s): Alan Mathers.

Approved By: Maternity Governance Group

Document Id: 499