MANAGING AND PREVENTING STROKES AT SEA

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Published: 14 October 2025

What is a stroke?
A stroke occurs when the blood supply to part of the brain is interrupted or reduced, preventing brain tissue from getting oxygen and nutrients. Within minutes, brain cells begin to die. Strokes are a medical emergency and require immediate attention.

There are two main types of stroke:

• Ischaemic stroke: Caused by a blockage (e.g. blood clot) in an artery supplying the brain.
• Haemorrhagic stroke: Caused by a blood vessel in the brain bursting.

A third, less severe type is a Transient Ischaemic Attack (TIA) or “mini-stroke,” where symptoms are temporary but still a warning sign of future strokes.

According to the World Health Organization (WHO), strokes are the second leading cause of death globally, responsible for approximately 6.5 million deaths annually[1] and a major cause of long-term disability.

Why is being able to recognise strokes important for seafarers?
In a remote environment with limited access to immediate medical support, a stroke at sea can be life-threatening and disabling, especially if not recognised and treated quickly. Everyone onboard has a key role in maintaining their own health, as well as looking out for those around them.  

How to spot a stroke: Think FAST

Recognising the signs of a stroke early can save lives and reduce long-term damage. Use the FAST acronym:

• F – Face drooping: Ask the person to smile. Is one side of the face drooping?
• A – Arm weakness: Ask them to raise both arms and keep them there. Does one arm drift downward?
• S – Speech difficulty: Is speech slurred or strange and can they understand what you say?
• T – Time to call: Call for emergency medical help immediately.

Other symptoms may include sudden:

• Numbness or weakness in the leg, arm, or face (especially on one side)
• Confusion or trouble understanding speech
• Trouble seeing in one or both eyes
• Trouble walking, dizziness, or loss of balance
• Severe headache with no known cause

Risk factors for stroke

Many risk factors for stroke are preventable or manageable. These include:

• High blood pressure (hypertension) – the leading cause of stroke
• Smoking
• Diabetes
• High cholesterol
• Obesity
• Physical inactivity
• Excessive alcohol consumption
• Atrial fibrillation (irregular heartbeat)

It is possible that stroke symptoms in women may present with more non-specific signs such as altered mental state (e.g. confusion, disorientation), generalised weakness and fatigue. It is important to have a high level of vigilance and seek medical help if any crew experience these symptoms.

Stroke prevention recommendations for seafarers

Keep your blood pressure under control

• If you’ve been prescribed medication, take it every day as directed.
• Bring enough medication for your contract and set reminders if needed.
• Check your blood pressure monthly or as advised by your doctor.

Look after your health daily

• Don’t smoke: Smoking damages blood vessels and raises stroke risk.
• Make healthy food choices: Meals low in salt, sugar, and saturated fats. Eat more fruits, vegetables, and whole grains.
• Stay active: Aim for 30 minutes of moderate exercise most days (e.g. walking, onboard workouts).
• Watch your weight: Losing excess weight helps lower blood pressure and stroke risk.
• Limit alcohol: No more than two drinks per day for men, one for women.

Know your medical history

• If you’ve had a mini-stroke (TIA), high blood pressure, diabetes, or irregular heartbeat, you’re at higher risk, so it is even more important that you follow the first two recommendations.
• Make sure your medical file is up to date and share relevant history during pre-employment checks.

If a stroke is suspected onboard: Act fast. Time is critical.

• Contact your telemedical provider (e.g. MedSea) without delay.
• Measure vital signs (blood pressure, heart rate, breathing rate, saturations, temperature) as well as blood sugar, if available on board.
• Record the time symptoms began.
• Keep the person calm and lying down with their head slightly elevated.
• Do not give food, drink, or medication unless instructed by a medical professional.

Final message to seafarers

Stroke prevention starts with you. By staying healthy, recognising the signs, and acting quickly, you can protect yourself. Your health is your responsibility—but you’re never alone. Reach out early, follow medical advice, and support each other onboard.

[1] World Health Organization. (2025). World health statistics 2025

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