Phase 1 study of use of 5% Carbogen in treatment of paediatric nonconvulsive status epilepticus

ISRCTN	ISRCTN80717736
DOI	https://doi.org/10.1186/ISRCTN80717736
Secondary identifying numbers	12223

Submission date: 17/05/2012
Registration date: 17/05/2012
Last edited: 12/12/2017

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Nervous System Diseases

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English Summary

Background and study aims
Non-convulsive status epilepticus (NCSE) happens in some kinds of childhood epilepsy. 'Status epilepticus' means continuous seizure activity. There are two kinds of status epilepticus. The common kind is known as convulsive status epilepticus. In this kind the seizures are very obvious to anyone watching. The other kind is called non-convulsive status epilepticus (NCSE) and is rarer. In NCSE there are few signs of a seizure although brain wave (electroencephalography [EEG]) recordings show that continuous seizure activity is happening. During NCSE what tends to be noticed is that a child is less responsive, drowsier or in some other way not as alert as usual. NCSE happens in a number of different childhood epilepsies and can be a recurring problem. Convulsive status epilepticus (the kind with externally obvious seizures) requires prompt medical treatment. NCSE is less of a medical emergency. There is no clear evidence that NCSE causes brain damage. Many of the current treatments for status epilepticus are sedating and repeated use of these medicines during a period of NCSE can cause additional problems such as chest infections or even a need for support on a breathing machine. We are running this study because we are looking for better treatments for NCSE. In this study we are testing whether breathing a medical gas called Carbogen for a short time is tolerated and whether it has any beneficial effects in treating NCSE.

Who can participate?
Children aged 0-16 with an established diagnosis of epilepsy of symptomatic or presumed symptomatic (cryptogenic) origin, in electrographically proven NCSE, admitted as inpatients for control of NCSE

What does the study involve?
If an EEG confirms NCSE in a child, they will breathe a 5% carbogen mixture by a face mask held over the mouth and nose with a gentle elastic strap. This will happen in the EEG department, and with the EEG still being recorded. The period of inhalation may change during the period of the trial in light of early experience. The inhalation will initially be for a period of 2 minutes (120 seconds): if it turns out that the first children involved in the study tolerate this well, it may be increased up to absolute maximum of 6 minutes. If it turns out that the first children involved in the study do not tolerate this well, the period will be shortened. Then the mask will be removed and your child will breathe room air as normal. We would continue to record the EEG for another 20 minutes and will study whether the EEG improves at all after breathing carbogen.

What are the possible benefits and risks of participating?
Carbogen is a mixture of two of the gases found in normal air and breathing carbogen is similar to re-breathing exhaled air (e.g. from a paper bag). Carbogen is already used in a number of other medical treatments and is a safe and well tolerated treatment. Breathing higher concentrations of carbogen than we are using in this study causes an urge to breathe (similar to that experienced if you hold your breath for a long time) which is unpleasant and can cause a sense of panic. But in the same way as this feeling goes away quickly once you start breathing normally again after holding your breath, it goes away rapidly as soon as carbogen inhalation is stopped. There may be no direct benefit to the child from taking part. The primary aim of this study is to see whether carbogen inhalation is well tolerated and acceptable but we are also interested in its usefulness as a treatment for NCSE. This may reduce the need for the child to receive other treatments but as yet this is not known.

Where is the study run from?
This study is being run in Newcastle and Manchester (UK)

When is the study starting and how long is it expected to run for?
Recruitment will start in June 2012 and will run for 2 years

Who is funding the study?
Epilepsy Research UK

Who is the main contact?
Dr Rob Forsyth (Chief Investigator and study lead in Newcastle)

Contact information

Mr Chris Speed
Scientific

University of Newcastle
Institute of Health and Society
21-23 Claremont Place
Newcastle Upon Tyne
NE2 4AA
United Kingdom

Phone	+44 (0)191 222 6000
Email	chris.speed@ncl.ac.uk

Study information

Study design	Non-randomised interventional trial
Primary study design	Interventional
Secondary study design	Non randomised study
Study setting(s)	Hospital
Study type	Treatment
Participant information sheet	Not available in web format, please use the contact details to request a patient information sheet
Scientific title	Phase 1 study of use of 5% Carbogen in treatment of paediatric conconvulsive status epilepticus
Study acronym	CONCEPT
Study hypothesis	Phase 1 study of use of 5% Carbogen in treatment of paediatric non-convulsive status epilepticus
Ethics approval(s)	North East - Sunderland Research Ethics Committee, 13/04/2012, ref: 12/NE/0005
Condition	Status epilepticus
Intervention	The intervention comprises administration of 5% carbogen by spontaneous inhalation administered via a loosely attached face mask (flow rate 5l/min) for a period stipulated by the protocol (timed by hand-held digital stopwatch).
Intervention type	Procedure/Surgery
Primary outcome measure	Four five-minute epochs of EEG will be excerpted for each patient. 5 mins prior to inhalation and 0-5, 5-10 and 10-15 minutes after completion of inhalation.
Secondary outcome measures	1. Assessment of safety 2. Capillary blood gas pH Measured at the end of the period of inhalation
Overall study start date	19/01/2012
Overall study end date	19/01/2014

Eligibility

Participant type(s)	Patient
Age group	Child
Upper age limit	16 Years
Sex	Both
Target number of participants	UK Sample Size: 30
Participant inclusion criteria	1. Child under 16 with known epilepsy (i.e. established tendency to recurrent seizures) 2. Aetiology of epilepsy known, or investigation deemed sufficient to infer a cryptogenic (presumed symptomatic) epilepsy 3. No clinical suspicion of current episode being associated with acutely raised intracranial pressure 4. Confirmed non-convulsive status epilepticus on EEG defined as the presence of 4.1. Bihemispheric 4.2. Continuous or near-continuous 4.3. Spikewave or other features indicative of seizure activity 4.4. History from parent, or other experienced carer familiar with the patient, of lower level of awareness than normal 5. Note that the presence of subtle continuing clinical seizure activity is not an exclusion criterion so long as the treating physician is satisfied that urgent treatment is not required. 6. Informed consent provided by parent/legal guardian
Participant exclusion criteria	1. Age > 16 years 2. Absence of informed consent from parent/legal guardian 3. Evidence of prior chronic respiratory disease and/or type 2 respiratory failure as indicated by a baseline (pre-inhalation) capillary blood gas pCO2 > 8kPa 4. Any clinical suspicion of a condition associated with acutely raised intracranial pressure 5. Currently involved in any other clinical trial of an investigative medical product
Recruitment start date	01/06/2012
Recruitment end date	19/01/2014

Locations

Countries of recruitment

England
United Kingdom

Study participating centre

University of Newcastle

Newcastle Upon Tyne
NE2 4AA
United Kingdom

Sponsor information

Newcastle Hospitals Foundation NHS Trust (UK)
Hospital/treatment centre

Wolfson Unit of Clinical Pharmacology
Institute of Cellular Medicine
High Heaton
Newcastle upon Tyne
NE7 7DN
England
United Kingdom

Phone	+44 (0)191 233 6161
Email	abc@email.com
Website	http://www.newcastle-hospitals.org.uk/
"ROR"	https://ror.org/05p40t847

Funders

Funder type

Charity

Epilepsy Research UK
Private sector organisation / Other non-profit organizations

Alternative name(s): ERUK
Location: United Kingdom

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
Publication and dissemination plan	Not provided at time of registration
IPD sharing plan

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
HRA research summary			28/06/2023	No	No

Editorial Notes

12/12/2017: No publications found, verifying study status with principal investigator.