Condition category
Pregnancy and Childbirth
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims
This is a study of infants suffering from perinatal asphyxia (lack of oxygen during birth) comparing standard care (cooling of the baby) with standard care and additional xenon gas inhaled through a ventilator. The study examines the feasibility and safety of inhaled xenon gas to see whether treatment with the combination of cooling and xenon gas may reduce brain injury, assessed by a MRI scan of the brain at around 8 days of age.

Who can participate?
Infants from 36 to 43 weeks gestation, following perinatal asphyxia

What does the study involve?
Infants are randomly allocated to one of two groups. One group is treated with intensive care and treatment with hypothermia (cooling) for 72 hours combined with inhaled xenon gas for 24 hours. The other group is treated with intensive care with hypothermia for 72 hours. MRI scans are performed once at between 4 - 10 days of age.

What are the possible benefits and risks of participating?
If the study is successful larger studies can be carried out to confirm whether treatment with xenon improves neurological (brain) function after birth asphyxia.

Where is the study run from?
Imperial College London (UK)

When is the study starting and how long is it expected to run for?
February 2012 to September 2014

Who is funding the study?
Medical Research Council (MRC) (UK)

Who is the main contact?
Dr Denis Azzopardi

Trial website

Contact information



Primary contact

Dr Denis Azzopardi


Contact details

Department of Paediatrics
Hammersmith House
DuCane Road
W12 5HS
United Kingdom

Additional identifiers

EudraCT number

2009-014344-11 number


Protocol/serial number

G0701714; prot-001-2009

Study information

Scientific title

Neuroprotective effects of hypothermia combined with inhaled xenon following perinatal asphyxia: a randomised controlled trial



Study hypothesis

Following perinatal asphyxia treatment with a combination of hypothermia and inhaled xenon preserves cerebral metabolism and structure.

Ethics approval

Not provided at time of registration

Study design

Randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Patient information can be found at:


Perinatal asphyxia with hypoxic-ischaemic encephalopathy


Infants will be allocated to one of two groups: intensive care and treatment with hypothermia for 72 hours combined with inhaled 30% xenon gas for 24 hours or intensive care with hypothermia for 72 hours. Magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) will be performed once between 4 - 10 days of age.

Intervention type



Not Applicable

Drug names


Primary outcome measure

Reduction in Lac/Naa ratio on magnetic resonance spectroscopy or preserved fractional anisotropy diffusion weighted magnetic resonance imaging.

Secondary outcome measures

Measured prior to hospital discharge:
1. Intracranial haemorrhage
2. Persistent hypotension
3. Pulmonary haemorrhage
4. Pulmonary hypertension
5. Prolonged blood coagulation time
6. Culture proven sepsis
7. Necrotising enterocolitis
8. Cardiac arrhythmia
9. Thrombocytopenia
10. Major venous thrombosis
11. Renal failure treated with dialysis
12. Pneumonia
13. Pulmonary airleak
14. Duration of hospitalisation

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Infants 36 to 43 weeks gestation (either sex) with at least one of the following:
1.1. Apgar score of less than 5 at 10 minutes after birth
1.2. Continued need for resuscitation, including endotracheal or mask ventilation, at 10 minutes after birth
1.3. Acidosis defined as pH less than 7.00 and/or base deficit x 16 mmol/L in umbilical cord blood sample or any blood sample within 60 minutes of birth (arterial or venous blood)
2. Moderate to severe encephalopathy consisting of altered state of consciousness (reduced or absent response to stimulation) and hypotonia, and abnormal primitive reflexes (weak or absent suck or Moro response). Clinical severity of hypoxic-ischaemic encephalopathy (HIE) will be assessed by Thompson encephalopathy score, and modified Sarnat score
3. At least 30 minutes duration of amplitude integrated EEG (aEEG) recording that shows moderately abnormal or suppressed background aEEG activity or seizures

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. If treatment with hypothermia is delayed beyond 6 hours, or infants are expected to be greater than 12 hours of age at the time of randomisation
2. Infants with ventilatory oxygen requirement greater than 70%
3. Attending clinician considers infant not suitable to participate because of other serious congenital abnormalities, or the infant's condition appears terminal

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Department of Paediatrics
W12 5HS
United Kingdom

Sponsor information


Imperial College London (UK)

Sponsor details

c/o Gary Roper
Hammersmith Campus
DuCane Road
W12 5HS
United Kingdom

Sponsor type




Funder type

Research council

Funder name

Medical Research Council (MRC) (UK) (ref: G0701714)

Alternative name(s)


Funding Body Type

government organisation

Funding Body Subtype

National government


United Kingdom

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

2015 results in

Publication citations

Additional files

Editorial Notes

17/03/2017: Plain English summary added. 29/12/2015: Publication reference added. 31/10/2014: The following changes were made to the trial record: 1. The overall trial start date was changed from 15/09/2009 to 01/02/2012 2. The overall trial end date was changed from 14/09/2012 to 30/09/2014 3. The target number of participants was changed from 130 to 92