AuthorisedTherapeutic use (Phase IV)Interventional

S-KETamine vs. propofol for prehospital sedation of patients with severe Acute Brain Injury: The KETABI randomised trial

When someone suffers a severe head injury or sudden bleeding in the brain, ambulance teams must act quickly. Paramedics often give medication to put the patient into a deep sleep so they can safely place a breathing tube and protect the brain. This trial compares two commonly used sedatives: S-ketamine and propofol. While both medicines are already used in emergency care, doctors want to find out which one does a better job of keeping blood pressure at a safe, steady level during the journey to the hospital. A sudden drop in blood pressure can reduce blood flow to an injured brain and cause more damage. Patients are randomly given one of the two medicines by the emergency team. Doctors will closely track their blood pressure and oxygen levels, and follow up six months later to see how well they have recovered.

At a glance

Status

Authorised

Phase

Therapeutic use (Phase IV)

Sponsor

Region Hovedstaden

Enrolment target

284

Start

27 Aug 2026

traumatic brain injury, subarachnoid haemorrhage, intracerebral haemorrhage

What is this study about?

When an adult suffers a sudden, severe brain injury—such as from a car crash, a fall, or bleeding in the brain—emergency care begins long before reaching the hospital. Paramedics often need to give strong calming medicines called sedatives. These drugs put the person into a deep sleep, allowing the medical team to place a breathing tube and help calm the injured brain.

Two medicines commonly used for this are propofol and S-ketamine. Both are effective, but they can affect the body in different ways. Propofol is very commonly used, but it can sometimes cause blood pressure to fall too low. S-ketamine is known to keep blood pressure higher, which might ensure the brain keeps getting the oxygen-rich blood it needs to heal. However, doctors need clear evidence to know which choice is truly safer.

The KETABI trial compares these two treatments directly in real-life emergencies. Emergency medical teams give either S-ketamine or propofol before transporting the patient to a major trauma centre. By learning which drug better protects blood pressure and oxygen levels, doctors hope to improve emergency guidelines and give future patients the best possible chance of a good recovery.

Key takeaways

The trial compares two standard emergency sedatives: S-ketamine and propofol.
It focuses on adults who need urgent sedation following a severe head injury or brain bleed.
The main goal is to find out which medicine keeps blood pressure most stable during transport.
Patients receive normal, high-level emergency care throughout their treatment.
A follow-up check takes place six months later to see how recovery is progressing.

Who may be eligible?

This trial is for adults aged 18 and over who have suffered a sudden, severe brain injury. This includes physical head injuries from accidents, as well as sudden bleeds inside or around the brain (such as a stroke or haemorrhage).

Because this study takes place during a life-threatening emergency, patients cannot sign up in advance. Emergency medical teams identify suitable patients at the scene of the injury. To be included, the person must need immediate deep sedation and a breathing tube to protect their airway.

People under 18 years of age, or those whose brain injuries are mild and do not require emergency sedation, cannot take part in this study.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Aged 18 or older
Has suffered a severe acute head injury or brain haemorrhage
Requires immediate sedation and breathing support by an emergency team
Treated by a participating emergency ambulance or medical crew

Answer every question to see your result.

What does participation involve?

Because this trial takes place during an acute emergency, treatment begins immediately at the scene of the injury. Paramedics or emergency doctors will give either S-ketamine or propofol through a drip. The patient's blood pressure, heart rate, and oxygen levels are recorded continuously during the ambulance journey and in the emergency department.

Once the patient is safely in the hospital, routine medical care continues as normal. The patient does not need extra hospital visits just for the trial. Around six months after the injury, researchers will contact the patient or their family to ask simple questions about their recovery, memory, and ability to carry out everyday activities. Taking part covers this single emergency treatment and the six-month follow-up check.

Potential risks and benefits

Both S-ketamine and propofol are approved medicines that doctors and paramedics use every day. Potential risks include sudden changes in blood pressure or heart rate, as well as low oxygen levels, which the emergency team is trained to manage immediately. A potential benefit is that the close monitoring required by the study helps ensure complications are spotted quickly. The research also helps improve emergency care for future patients. Because treatment happens during an unconscious emergency, consent is usually obtained later from the patient or their family. Patients or their representatives can choose to withdraw from the study at any time without affecting their medical care.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
Denmark

Common questions

Why wasn't consent asked for before giving the medicine?

Because severe brain injuries are life-threatening and cause unconsciousness, doctors must treat the patient immediately. Families or patients are spoken to as soon as possible after the emergency to explain the study and seek permission to continue.

Are these medicines brand new or experimental?

No. Both propofol and S-ketamine are well-established anaesthetic medicines used in hospitals and ambulances across the UK and worldwide.

Can patients or families choose which drug is given?

No. A computer randomly decides which medicine is given so that researchers can fairly compare how well each drug works.

Will taking part change hospital treatment?

No. The study only involves the emergency sedation medicine given on the way to hospital. All hospital care, surgeries, and scans follow standard NHS guidelines.

What happens at the six-month follow-up?

The research team will check in, usually by phone or questionnaire, to see how the patient is recovering and managing daily tasks.