Hypoglycemia; IatrogenicFIGSNCT07259629
Fasting Induced Hypoglycaemia in Anaesthetised Paediatric Patients
An observational study of Hypoglycemia; Iatrogenic and Anesthesia, run by Guy's and St Thomas' NHS Foundation Trust at 24 sites in United Kingdom.
Trial summary
Fasting is a requirement to safely anesthetise patients referred for elective procedure, using the traditional 6/4/2 rule (6h for solid food or formula milk, 4h for breast milk and 2h for clear fluids), applied to all patients regardless of their age or weight. Read more about this study
- Who is it for?
- Ages 1 month to 18 yearsHealthy volunteers can take part
- Conditions the study is for
- Hypoglycemia; Iatrogenic, Anesthesia, Pediatrics
- How many people
- 2,902 participants
- Where
- 24 sitesUnited Kingdom
- Study dates
- 12 May 2025to 18 May 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 1 month to 18 years
- All sexes
- Healthy volunteers accepted
- Child, Adult
Study population: Pediatric patients fasting for a procedure under general anesthesia
Who may be able to join
- All American Society of Anesthesiology score (ASA) 1 - 3 children aged 1 month to 18 years presenting for an elective procedure involving general anaesthesia during the defined study period
- All elective cases, day cases will be included (patient's admitted the night before for bowel preparation prior to elective colonoscopy should also be included)
- Planned expedited cases in ASA 1 / 2 children should be included, for example nail bed repairs, lacerations, foreign body (in ear / eye / nose), simple fractures for manipulation under anesthesia / k-wires
- MRI, radiology and dental cases will be included provided the patient receives a general anaesthetic
Who cannot join
- Children aged less than 1 month
- Procedures performed under oral sedation or local anaesthesia only
- ASA status 4 and 5
- Children with any endocrine or metabolic condition or who have a fasting plan prior to general anaesthesia for glucose control:
- Type 1 or 2 diabetes mellitus, medium chain acetyl Co-enzyme A, maple syrup urine disease, glycogen storage disease, galactosaemia, urea cycle defects, familial hypercholesterolaemia, congenital disorders of glycosylation, lysosomal storage disorders, organic acidaemias, mitochondrial disorders, adrenal gland disorders, adrenoleukodystrophy, growth disorders, lipid disorders, multiple endocrine neoplasia type 1 and 2, pituitary disorders.
- Emergency and oncology procedures as these children will have different risk factors for hypoglycaemia
Show all 9Show fewer
- Anaesthetic involvement in critically ill children e.g. airway management in emergency department, pediatric intensive care unit
- Children on glucose containing intravenous solutions or total parenteral nutrition pre-operatively
- Children on systemic steroid treatment (oral / intravenous). Children on inhalers / topical steroids should be included
Trial locations and contacts
24 sites in 1 country.
24 sites in 1 country
United Kingdom24 sites
Royal Aberdeen Infirmary
Aberdeen
Royal Belfast Hospital for Sick Children
Belfast
Ulster Hospital
Belfast
Birmingham Women and Children's Hospital
Birmingham
Addenbrooke's Hospital
Cambridge
Children's Hospital of Wales
Cardiff
Ninewells Tayside Hospital
Dundee
Royal Hospital for Sick Children
Edinburgh
Royal Devon University Healthcare NHS Foundation Trust
Exeter, Devon, EX2 5DW
Royal Hospital for Children
Glasgow
Buckinghamshire Healthcare NHS Foundation Trust
High Wycombe
Moorfields Eye Hospital
London, EC1V 2PD
Evelina London Children's Hospital
London, SE17EH
Chelsea and Westminster Hospital
London
King's College Hospital
London
Royal London Hospital
London
St George's Hospital
London
St Mary's Hospital
London
James Cook University Hospital
Middlesbrough
Great Northern Children's Hospital
Newcastle
Nottingham Children's Hospital
Nottingham
University hospital of Plymouth
Plymouth
Salisbury NHS Foundation Trust
Salisbury
Sheffield Children's Hospital
Sheffield
About this study
Fasting is a requirement to safely anesthetise patients referred for elective procedure, using the traditional 6/4/2 rule (6h for solid food or formula milk, 4h for breast milk and 2h for clear fluids), applied to all patients regardless of their age or weight. Reducing the aspiration risk however puts young children at higher risk of hypoglycemia due to the immaturity of their endocrine system and absence of metabolic reserves. The Association of Paediatric Anaesthetists of Great Britain and Ireland recommends that during day case surgery the majority of children may be given fluids without dextrose, provided blood glucose is monitored. Recent statements recommend continuing fluids until 1h before the procedure or even to give fluids when anesthetists sent for the patients. Hypoglycemia is rare in children above 2 years of age. Although the definition of hypoglycemia can differ, a threshold of 3.6mmol/l is often used given the potential neurological harm existing below this value. There is no consensus on the definition of hypoglycemia in children being fasted prior to general anesthesia, nor when nor how to treat it. Measurements are done for complex surgeries or patients deemed at risk according to the anesthetists. An audit was run in 2017 at the " Evelina London Children's Hospital ", Guy's and St Thomas' National Health Service Foundation Trust, identifying 8% of children below 2 years of age as hypoglycemic. Recent review of our Incident Reporting Systems identified 3 cases, in otherwise fit and healthy children, referred for colonoscopy with initial hypoglycemia followed by rebound hypoglycemia after management. There is an urgent need to establish a clear definition of hypoglycemia and investigate risk factors in paediatric patients referred for elective procedures under general anesthesia.
- Conditions
- Hypoglycemia; Iatrogenic, Anesthesia, Pediatrics
- Medical subject headings
- Hypoglycemia
What is being measured
The primary outcome is the main question the study is designed to answer.
Hypoglycaemia
Blood glucose values triggering a response from the anaesthetists with initiation of a hypoglycaemia treatment following a blood glucose measurement during anaesthetic induction. Decision to diagnose hypoglycaemia and treat it by the anaesthetist
Measured: Immediately/within five minutes after anesthesia induction
Secondary outcomes (7)
4mmol/l as a suitable threshold of hypoglycemia
Number of patient with a blood glucose measurement below 4mmol/l and being treated as hypoglycaemic by an anaesthetist following a blood glucose measurement during anaesthetic induction
Measured: Immediately/within five minutes after anesthesia induction
Distribution of glycemic measurements in fasting children
Blood glucose values in children undergoing elective procedure under general anaesthesia.
Measured: Immediately/within five minutes after anesthesia induction
Age as a risk factor of hypoglycaemia
Number of children below 24 months of age reported as hypoglycaemic by an anaesthetist following a blood glucose measurement during anaesthetic induction
Measured: Immediately/within five minutes after anesthesia induction
Weight as a risk factor of hypoglycaemia
Number of children weighing less than 10kg and considered as hypoglycaemic by an anaesthetist following a blood glucose measurement during anaesthetic induction
Measured: Immediately/within five minutes after anesthesia induction
Distribution of blood ketone measurements in children fasting
Blood ketone values in children undergoing elective procedure under general anaesthesia.
Measured: Immediately/within five minutes after anesthesia induction
3.3mmol/l as a suitable threshold of hypoglycemia
Number of patient with a blood glucose measurement below 3.3mmol/l and being treated as hypoglycaemic by an anaesthetist following a blood glucose measurement during anaesthetic induction
Measured: Immediately/within five minutes after anesthesia induction
3.6mmol/l as a suitable threshold of hypoglycemia
Number of patient with a blood glucose measurement below 3.6mmol/l and being treated as hypoglycaemic by an anaesthetist following a blood glucose measurement during anaesthetic induction
Measured: Immediately/within five minutes after anesthesia induction
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Dec 2025
- Study start12 May 2025
- Primary completion18 May 2026
- Study completion18 May 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Hypoglycemia; IatrogenicStudies of the same condition, open and under way.
- More trials run by Guy's and St Thomas' NHS Foundation TrustThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 2,902 participants (actual)
Sponsor and investigators
- Lead sponsor
- Guy's and St Thomas' NHS Foundation Trust
- Sponsor type
- University, hospital or other
- Collaborators
- Evelina London Children's Charity, Nova Biomedical, Kings Health Partners
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07259629
- Sponsor's protocol ID
- 329701
- Acronym
- FIGS
- Status last verified
- Jul 2026
- First submitted
- 16 Jul 2024
- Last updated
- 22 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Lewis HF, Lemonde H, Gale C, Jones G, Logan K, Ayis S, Vincent A, MacCarrick T, Parnell J, Delgaty N, Wagster E, Favero S, Blaise BJ. Fasting-induced hypoglycaemia in anaesthetised paediatric patients (FIGS): protocol of an opt-out approach to consent for a multicentre cohort study measuring glycaemia and ketonaemia. BJA Open. 2026 Sep 23;20:100863. doi: 10.1016/j.bjao.2026.100863. eCollection 2026 Dec.
PubMed 42831233
Study at a glance
From the registry record, last updated by the sponsor on 22 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Fasting Induced Hypoglycaemia in Anaesthetised Paediatric Patients
- ClinicalTrials.gov ID
- NCT07259629
- Acronym / sponsor ID
- FIGS / 329701
- Conditions
- Hypoglycemia; Iatrogenic, Anesthesia, Pediatrics
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 2,902 participants (actual)
- Lead sponsor
- Guy's and St Thomas' NHS Foundation TrustUniversity, hospital or other
- Collaborators
- Evelina London Children's Charity, Nova Biomedical, Kings Health Partners
- Study start
- 12 May 2025 (actual)
- Primary completion
- 18 May 2026 (actual)
- Study completion
- 18 May 2026 (actual)
- First posted
- 2 Dec 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Fasting is a requirement to safely anesthetise patients referred for elective procedure, using the traditional 6/4/2 rule (6h for solid food or formula milk, 4h for breast milk and 2h for clear fluids), applied to all patients regardless of their age or weight. Reducing the aspiration risk however puts young children at higher risk of hypoglycemia due to the immaturity of their endocrine system and absence of metabolic reserves. The Association of Paediatric Anaesthetists of Great Britain and Ireland recommends that during day case surgery the majority of children may be given fluids without dextrose, provided blood glucose is monitored. Recent statements recommend continuing fluids until 1h before the procedure or even to give fluids when anesthetists sent for the patients. Hypoglycemia is rare in children above 2 years of age. Although the definition of hypoglycemia can differ, a threshold of 3.6mmol/l is often used given the potential neurological harm existing below this value. There is no consensus on the definition of hypoglycemia in children being fasted prior to general anesthesia, nor when nor how to treat it. Measurements are done for complex surgeries or patients deemed at risk according to the anesthetists. An audit was run in 2017 at the " Evelina London Children's Hospital ", Guy's and St Thomas' National Health Service Foundation Trust, identifying 8% of children below 2 years of age as hypoglycemic. Recent review of our Incident Reporting Systems identified 3 cases, in otherwise fit and healthy children, referred for colonoscopy with initial hypoglycemia followed by rebound hypoglycemia after management. There is an urgent need to establish a clear definition of hypoglycemia and investigate risk factors in paediatric patients referred for elective procedures under general anesthesia.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 1 month to 18 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult
- Study population
- Pediatric patients fasting for a procedure under general anesthesia
Key inclusion criteria (4 listed)
- All American Society of Anesthesiology score (ASA) 1 - 3 children aged 1 month to 18 years presenting for an elective procedure involving general anaesthesia during the defined study period
- All elective cases, day cases will be included (patient's admitted the night before for bowel preparation prior to elective colonoscopy should also be included)
- Planned expedited cases in ASA 1 / 2 children should be included, for example nail bed repairs, lacerations, foreign body (in ear / eye / nose), simple fractures for manipulation under anesthesia / k-wires
- MRI, radiology and dental cases will be included provided the patient receives a general anaesthetic
Key exclusion criteria (9 listed)
- Children aged less than 1 month
- Procedures performed under oral sedation or local anaesthesia only
- ASA status 4 and 5
- Children with any endocrine or metabolic condition or who have a fasting plan prior to general anaesthesia for glucose control:
- Type 1 or 2 diabetes mellitus, medium chain acetyl Co-enzyme A, maple syrup urine disease, glycogen storage disease, galactosaemia, urea cycle defects, familial hypercholesterolaemia, congenital disorders of glycosylation, lysosomal storage disorders, organic acidaemias, mitochondrial disorders, adrenal gland disorders, adrenoleukodystrophy, growth disorders, lipid disorders, multiple endocrine neoplasia type 1 and 2, pituitary disorders.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Hypoglycaemia
Time frame: Immediately/within five minutes after anesthesia induction
Blood glucose values triggering a response from the anaesthetists with initiation of a hypoglycaemia treatment following a blood glucose measurement during anaesthetic induction. Decision to diagnose hypoglycaemia and treat it by the anaesthetist
7 secondary outcomes
4mmol/l as a suitable threshold of hypoglycemia
Time frame: Immediately/within five minutes after anesthesia induction
Distribution of glycemic measurements in fasting children
Time frame: Immediately/within five minutes after anesthesia induction
Age as a risk factor of hypoglycaemia
Time frame: Immediately/within five minutes after anesthesia induction
Weight as a risk factor of hypoglycaemia
Time frame: Immediately/within five minutes after anesthesia induction
Distribution of blood ketone measurements in children fasting
Time frame: Immediately/within five minutes after anesthesia induction
3.3mmol/l as a suitable threshold of hypoglycemia
Time frame: Immediately/within five minutes after anesthesia induction
3.6mmol/l as a suitable threshold of hypoglycemia
Time frame: Immediately/within five minutes after anesthesia induction
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 Jul 2026.
- Derived from this study: PubMed 42831233Lewis HF, Lemonde H, Gale C, Jones G, Logan K, Ayis S, Vincent A, MacCarrick T, Parnell J, Delgaty N, Wagster E, Favero S, Blaise BJ. Fasting-induced hypoglycaemia in anaesthetised paediatric patients (FIGS): protocol of an opt-out approach to consent for a multicentre cohort study measuring glycaemia and ketonaemia. BJA Open. 2026 Sep 23;20:100863. doi: 10.1016/j.bjao.2026.100863. eCollection 2026 Dec.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
24 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Hypoglycemia; Iatrogenic and Anesthesia, run by Guy's and St Thomas' NHS Foundation Trust at 24 sites in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 22 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 24 sites in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Hypoglycaemia (time frame: Immediately/within five minutes after anesthesia induction). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07259629, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 Jul 2026.