Intrapartum Fetal ST- Analysis Clinical Guideline V 2.0 January 2019 · 2.9.3 The STAN CTG Identifier number (e.g. 1RC00001) must be recorded in the maternal notes on the initial

Intrapartum Fetal

ST- Analysis Clinical Guideline

V 2.0

January 2019

Intrapartum Fetal ST-Analysis Clinical Guideline v2.0

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Summary.

Prior to commencing ST-Analysis Exclude contraindications Consider overall clinical picture

Classify CTG as per FIGO

Normal – or evidence of sufficient fetal reserves to respond to hypoxia (i.e. stable

baseline and normal variability). Consider FBS if in doubt. Commence ST-analysis

Pre-terminal CTG

Deliver Immediately

STAN event detected in labour

Classify CTG as per FIGO

Normal CTG:

Ignore ST events

CTG suspicious or pathological: Check the type and magnitude of the ST event and

reclassify ST event according to STAN guidelines

Significant ST events Take action – this could be stopping syntocinon, giving terbutaline, maternal position change or

immediate delivery A significant ST event in the active second stage

should prompt immediate delivery

Non-significant ST event No action need to be taken

but consider the overall picture and assess CTG trace every 60 minutes to exclude features of fetal

decompensation


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1. Aim/Purpose of this Guideline 1.1. This document gives guidance for obstetricians and midwives on the usage and interpretation of ST Analysis (using a STAN monitor) of intrapartum fetal electrocardiotocography (ECG). 1.2. This guideline should be read in conjunction with the Royal Cornwall Hospital Trust (RCHT) guidance: ‘Clinical Guideline for the use of Electronic Fetal Monitoring (EFM) in Labour, Fetal Blood Sampling (FBS) and Paired Cord Sampling’

2. The Guidance 2.1. Definition and background ST- analysis is an adjunct to cardiotocography (CTG) monitoring which aims to detect fetal hypoxia in order to aid the management of labour. STAN technology works by determining a normal baseline ECG for each individual fetus. It is important that the fetus still has the capacity to respond to hypoxia. Analysing the CTG prior to and during ST-analysis is crucial. Fetal ECG refers to a graphic record of the electrical activity of myocardial cells. This reflects the oxygenation of the myocardium – this is a central fetal organ therefore indirectly provides information about the oxygenation of the fetal brain. STAN specifically analyses T/QRS ratios and ST segment changes of fetal ECG complexes and produces 2 types of ST events: T/QRS events and Biphasic ST events. Due to the analysis of ECG complexes, STAN provides continuous information on fetal wellbeing throughout labour. 2.2. Who should be offered ST-analysis as an adjunct to CTG?

2.2.1 All women in labour who are at risk of developing fetal hypoxia/acidosis may benefit from ST- analysis. Therefore, the indications for ST-analysis are the same as those for CTG monitoring – please refer to RCHT EFM Guideline as referenced above. Women should be counselled regarding the rationale for CTG/STAN usage, and its risks and limitations if appropriate.

2.2.2 The following are CONTRAINDICATIONS to the use of ST-analysis:

Maternal blood borne disease e.g. HIV, Hepatitis B, active herpes.

Prematurity <36+0.

Intact membranes. o The fetal scalp electrode should NOT be used to rupture

membranes, if artificial rupture of membranes (ARM) is indicated to commence ST analysis use an amnihook .

Suspicion of fetal bleeding disorder.

Prior to established labour.

Any contraindication to vaginal examination e.g. placenta praevia


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Woman declines its use.

ST-analysis should not be commenced in ACTIVE second stage.

2.2.3 STAN monitors are limited on delivery suite. Priority should be given to those women at significant risk of developing fetal hypoxia/acidosis or where there are concerns regarding the fetal heart.

2.3 Commencing STAN

2.3.1 Having identified a significant risk of developing fetal hypoxia or acidosis, ST-analysis should be commenced as early as possible, preferably while the CTG is normal.

2.3.2 However, even if the CTG classification is suspicious or pathological, if the fetal heart baseline is clearly determined and variability 5bpm or over, fetal hypoxia can be excluded and ST-analysis can be commenced. 2.3.3 After 20 minutes of CTG and/or at initiation of ST Analysis, complete the “Initial cardiotocography assessment” sticker and place in the contemporaneous maternity record. A management plan indicating the most appropriate method for intrapartum fetal monitoring is documented (New 2019)

2.3.4 The initial CTG should be assessed as per FIGO guidelines (please see RCHT EFM guideline). If the CTG is thought to reflect a hypoxic fetus, an FBS may be performed prior to starting ST-analysis. If the CTG is pre-terminal or if FBS is not possible then immediate delivery is indicated (see flow chart in Summary section of this guideline). 2.3.5 ST-analysis must not be started in the active 2nd stage labour.


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2.3.6 If a STAN event occurs when the CTG is suspicious or pathological, the CTG should be interpreted using the modified FIGO guidelines as summarised below:

2.4. Electrode Placement: A specialised spiral fetal scalp electrode must be applied:-

2.4.1 Avoid large areas of caput. 2.4.2 Hold the electrode firmly on the fetal presenting part and rotate

clockwise at least 1.25 turns. Resistance should then be felt on gentle traction.

2.4.3 Check the FSE is not applied to maternal tissue.

Additionally a reference electrode is placed on the mother’s thigh in order to differentiate maternal ECG waveforms.

2.4.4 Only use a STAN approved skin electrode. 2.4.5 Place on upper inner thigh. 2.4.6 Large muscle (e.g. quadriceps) can cause interference. 2.4.7 Use elasticated belts to hold the leg plate in place.

TENS machines also interfere with the ECG waveform and so should be during ST-analysis.

2.5 STAN can be used in breech presentation with the safe application of the electrode.

BREECH MODE must be selected on the STAN monitor. 2.6 A tocodynamometer is placed abdominally to monitor contractions as in normal CTG monitoring.


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2.7 The STAN SCREEN

2.7.1 The STAN monitor displays the cardiotocograph in a similar way to standard CTG monitoring. Additionally, the channel below the tocograph displays a series of black ‘x’s’ (see below). Each ‘x’ represents the analysis of 30 ECG complexes and therefore heartbeats. 2.7.2 At initial setup, the event log will report ‘Baseline T/QRS determined’ after 20 crosses (this usually takes 4-5 minutes). 2.7.3 Signal quality should be considered poor in the following circumstances:

4 minutes of CTG without T/QRS complexes (‘x’)

Less than one T/QRS (‘x’) occurs in each 1 minute of the CTG.

2.7.4 In these circumstances, a STAN event may have been missed and subsequent ST-analysis may be unreliable. 2.7.5 The CTG must then be classified using FIGO; if this is pathological, action will be required even if there is no STAN event. 2.7.6 STAN will remember its initial assessment of the baseline fetal ECG for 2 hours and can be relied upon if adequate signal quality is re-obtained within this time period and the CTG has not been classified as pathological using FIGO. 2.7.7 The generation of STAN events relies on the ability of the fetus to respond to hypoxia. In severe cases, this ability may be compromised and so a further STAN event may not be generated. This highlights the importance of not ignoring STAN events or periods of poor signal.

2.8 STAN Events

Significant STAN events are generated by the monitors and reported as black boxes on the CTG monitor (along with an audible ‘beep’). STAN events are of 3 types – episodic T/QRS rise, baseline T/QRS rise and biphasic ST. The significance of these events must be determined within the context of the CTG classification as detailed below:


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2.8.1 If a significant STAN event occurs, intervention is required.

This will usually involve improving the fetal environment by changing maternal position, reducing the strength/ frequency of uterine contractions (stopping or reducing oxytocin and/or administering subcuticular terbutaline), or administering IV fluids. 2.8.2 If, despite appropriate intervention, the CTG does not promptly improve, delivery is indicated. The timing of delivery is dependent upon the whole clinical picture; this will determine whether it is a Category 1 or Category 2 delivery. 2.8.3 During the active second stage of labour, the intervention will usually be delivery of the baby, unless spontaneous delivery is anticipated within the next 5-10 minutes. Non-significant ST events in 2nd stage do not warrant delivery of the baby. 2.8.4 If a pathological CTG persists beyond 60 minutes in active second stage, then delivery should be achieved even without ST events occurring, unless spontaneous delivery is anticipated within the next 10 minutes. This is because fetal hypoxia or acidosis may develop rapidly during prolonged active second stage.

2.8.5 STAN events may occur in the presence of a NORMAL CTG. These represent the normal physiological adaption of the fetus to the stresses of labour and should not be acted upon outside the context of standard CTG interpretation. 2.8.6 In cases of maternal pyrexia/suspected chorioamnionitis, it is important to remember that hypoxia is not the only pathway to brain damage. Also, a co-existing infection may enhance the damaging effects of hypoxia on the fetal brain. 2.8.7 In the presence of suspected chorioamnionitis, any ST event is significant, unless the CTG is normal.


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2.9 Documentation

2.9.1 The patient history should be recorded in the Event Log on the MOSOS electronic system. All these entries are identifiable by the unique code for each staff member. NEW 2019 on the STAN monitor. This log should be updated with any significant intrapartum events. 2.9.2 Any STAN events must be recorded in the maternal intrapartum notes, along with a CTG classification and what action (if any) is taken. 2.9.3 The STAN CTG Identifier number (e.g. 1RC00001) must be recorded in the maternal notes on the initial CTG assessment sticker and in the MOSOS event log (NEW 2019) at commencement of STAN.

2.10 Troubleshooting lack of signal 2.10.1 Inspect the information window for messages.

2.10.2 Check whether normal fetal ECG complexes can be seen on the screen. 2.10.3 Make sure the maternal skin electrode is properly applied.

2.10.4 Check the scalp electrode is attached to the fetal scalp (not the cervix) and not loose. If necessary apply a new electrode. 2.10.5 If a STAN signal cannot be obtained, the monitor can still be used for CTG only.


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3. Monitoring compliance and effectiveness

Element to be monitored

Appropriate commencement of STAN monitoring Appropriate obstetric intervention according to STAN guideline

Lead Fetal monitoring lead midwife

Tool Is the rationale for commencing appropriate Are appropriate interventions undertaken and accordance with STAN guideline If the trace was assessed as being intermediary or abnormal was the plan of care and action taken documented in the maternal notes

Frequency Annually - 1% or 10 sets, whichever the greatest, of all health records of women who have had FBS, EFM and paired cord sampling Annually - 1% or 10 sets, whichever the greater, of all health records of women where there has been concern about the baby in labour, or immediately following birth, in whom paired cord sampling only has been undertaken

Reporting arrangements

Maternity Patient Safety Forum

Acting on recommendations and Lead(s)

Any deficiencies identified at Patient Safety meetings will be discussed at the Patient Safety Forum and an action plan developed Action leads will be identified and a time frame for the action to be completed by The action plan will be monitored by the Maternity Patient Safety Forum or Clinical Audit Forum until all actions complete

Change in practice and lessons to be shared

Required changes to practice will be identified and actioned within a time frame agreed on the action plan The fetal monitoring lead midwife takes each change forward where appropriate The results of the audits will be distributed to all staff through the Patient Safety Newsletter or Practice Development newsletter and Clinical Audit Forum as per the action plan


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4. Equality and Diversity 4.1. This document complies with the Royal Cornwall Hospitals NHS Trust service Equality and Diversity statement which can be found in the 'Equality, Diversity & Human Rights Policy' or the Equality and Diversity website.

4.2. Equality Impact Assessment

The Initial Equality Impact Assessment Screening Form is at Appendix 2.

http://www.rcht.nhs.uk/GET/d10268876

http://www.rcht.nhs.uk/GET/d10268876

http://www.rcht.nhs.uk/RoyalCornwallHospitalsTrust/OurOrganisation/EqualityAndDiversity/HumanRightsEqualityAndInclusion.aspx


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Appendix 1. Governance Information

Document Title Intrapartum Fetal ST-Analysis Clinical Guideline v2.0

Date Issued/Approved: 10th January 2019

Date Valid From: 22nd January 2019

Date Valid To: 10th January 2022

Directorate / Department responsible (author/owner):

Obstetrics & Gynaecology Directorate Sally Budgen Senior Midwife Fetal monitoring

Contact details: 01872-252361

Brief summary of contents

This document gives guidance for obstetricians and midwives on the usage and interpretation of ST Analysis (using a STAN monitor) of intrapartum fetal electrocardiotocography

Suggested Keywords:

CTG, EFM, monitoring, FBS, cord, labour, NICE fetal, blood, sampling, labour, paired, trace

Target Audience RCHT CFT KCCG

Executive Director responsible for Policy:

Medical Director

Date revised: January 2019

This document replaces (exact title of previous version):

Clinical Guideline for Intrapartum Fetal ST- Analysis v1.0

Approval route (names of committees)/consultation:

Maternity Guideline Group Obs & Gynae Directorate Divisional Board for noting

Divisional Manager confirming approval processes

Head of Midwifery

Name and Post Title of additional signatories

Not required

Name and Signature of Divisional/Directorate Governance Lead confirming approval by specialty and divisional management meetings

{Original Copy Signed}

Name: Name: Caroline Amukusana

Signature of Executive Director giving approval

{Original Copy Signed}


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Publication Location (refer to Policy on Policies – Approvals and Ratification):

Internet & Intranet Intranet Only

Document Library Folder/Sub Folder Clinical/Midwifery and Obstetrics

Links to key external standards CNST 2.3 & 2.4

Related Documents:

References:

1. The Physiology of Fetal Surveillance (The Green Book of Neoventa Part1) K Rosen & Annika Martendal 2014 Neoventa Medical

2. STAN: An introduction to its use, limitations and caveats. Edwin Chandraharan 2010 www.neoventa.com

3. Townsend R & Chandraharan E. Fetal ECG (ST analysis); An evolving standard for intrapartum fetal surveillance. Chapter in: Current Progress in Obstetrics and Gynaecology, 2015.

Training Need Identified? Yes – All staff providing intrapartum care will complete the recognised STAN training and competency assessment.

Version Control Table

Date Version

No Summary of Changes

Changes Made by (Name and Job Title)

9/1/2017 V1.0 Initial Issue

Sally Budgen Senior Midwife, fetal monitoring Richard Keedwell, Obs & Gynae Speciality Registrar

10/1/2019 V2.0

2.3.3 Addition of the CTG sticker and management plan. 2.9.1 Addition of the event log on MOSOS 2.9.4 Recording of the STAN identifier number in the MOSOS event log.

Sally Budgen Senior Midwife, fetal monitoring

[Please complete all boxes and delete help notes in blue italics including this note]

All or part of this document can be released under the Freedom of Information

Act 2000

This document is to be retained for 10 years from the date of expiry.

This document is only valid on the day of printing


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Controlled Document

This document has been created following the Royal Cornwall Hospitals NHS Trust Policy on Document Production. It should not be altered in any way without the

express permission of the author or their Line Manager.


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Appendix 2. Initial Equality Impact Assessment Form

This assessment will need to be completed in stages to allow for adequate consultation with the relevant groups.

Name of the strategy / policy /proposal / service function to be assessed


Directorate and service area: Obstetrics and Gynaecology

Is this a new or existing Policy: Existing

Name of individual completing assessment: Sally Budgen

Telephone: 01872 252361

1. Policy Aim* Who is the strategy / policy / proposal / service function aimed at?

The aim of this guideline is guidance for obstetricians and midwives on the usage and interpretation of ST Analysis (using a STAN monitor) of intrapartum fetal electrocardiotocography.

2. Policy Objectives*

Early detection of fetal hypoxia by the usage and interpretation of ST Analysis (using a STAN monitor) of intrapartum fetal electrocardiotocography and the appropriate management

3. Policy – intended Outcomes*

Improved outcome for the new born baby

4. *How will you measure the outcome?

Compliance monitoring tool

5. Who is intended to benefit from the policy?

All pregnant women

6a Who did you consult with b). Please identify the groups who have been consulted about this procedure.

Workforce Patients Local groups

External organisations

Other

x

Maternity Guidelines Group Maternity Directorate Care Group Board Meeting for noting Policy Review Group


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Are there concerns that the policy could have differential impact on:

Equality Strands: Yes No Unsure Rationale for Assessment / Existing Evidence

Age x

Sex (male,

female, trans-gender / gender reassignment)

x

Race / Ethnic communities /groups

x

Disability - Learning disability, physical impairment, sensory impairment, mental health conditions and some long term health conditions.

x

Religion / other beliefs

x

Marriage and Civil partnership

x

Pregnancy and maternity

x

Sexual Orientation, Bisexual, Gay, heterosexual, Lesbian

x

You will need to continue to a full Equality Impact Assessment if the following have been highlighted:

You have ticked “Yes” in any column above and

No consultation or evidence of there being consultation- this excludes any policies which

have been identified as not requiring consultation. or

Major this relates to service redesign or development

What was the outcome of the consultation?

Guideline agreed

7. The Impact Please complete the following table. If you are unsure/don’t know if there is a negative impact you need to repeat the consultation step.


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8. Please indicate if a full equality analysis is recommended. Yes No x

9. If you are not recommending a Full Impact assessment please explain why.

Not required

Signature of policy developer / lead manager / director Sally Budgen, Senior Midwife, Fetal Monitoring

Date of completion and submission January 2019

Names and signatures of members carrying out the Screening Assessment

1. Sally Budgen, Senior Midwife Fetal Monitoring 2. Human Rights, Equality & Inclusion Lead

Keep one copy and send a copy to the Human Rights, Equality and Inclusion Lead c/o Royal Cornwall Hospitals NHS Trust, Human Resources Department, Knowledge Spa, Truro, Cornwall, TR1 3HD This EIA will not be uploaded to the Trust website without the signature of the Human Rights, Equality & Inclusion Lead. A summary of the results will be published on the Trust’s web site. Signed _____January 2019_________ Date ________Sarah-Jane Pedler________