Applying an Arterial Tourniquet – OSCE Guide

Catastrophic external haemorrhage is one of the most time-critical prehospital emergencies. In such cases, rapid control of bleeding is essential to prevent exsanguination and death. Life-threatening haemorrhage from a limb can result in death within minutes if not properly managed.¹

Tourniquets are one of the few interventions in prehospital trauma care that are consistently associated with improved survival when used appropriately. They are designed to stop arterial flow to a limb by compressing the vasculature against the underlying bone, buying critical time for definitive care.^2-3

This guide provides a step-by-step approach to applying an arterial tourniquet in an OSCE setting; it is NOT intended to be used to guide patient care.

Arterial tourniquet

Indications

Indications for applying a tourniquet include:

• Catastrophic external limb haemorrhage uncontrolled by direct pressure
• Traumatic amputations or degloving injuries ^{1-2, 4}

Cautions and clinical considerations

Cautions and considerations for applying a tourniquet include:

• Always record the time of tourniquet application clearly and visibly
• Tourniquets must never be applied over a joint
• Avoid covering with clothing, as visual monitoring is essential
• For frail, burnt or compromised skin, consider padding with gauze
• Tourniquet removal or loosening should only be performed by clinicians competent to assess bleeding control and manage complications ^3-5

Gather equipment

Gather the appropriate equipment for applying an arterial tourniquet:

• Arterial tourniquet (e.g. CAT, SAM XT)
• Means of recording application time (pen, label, marker)
• Non-sterile gloves
• Apron
• Eye protection
• Pre-hospital PPE, if relevant (e.g. hi-visibility jacket or tabard, helmet, reinforced boots, hearing protection)

Introduction

Wash your hands using alcohol gel. If your hands are visibly soiled, wash them with soap and water.

Don PPE if appropriate.

Introduce yourself to the patient including your name and role.

Confirm the patient’s name and date of birth.

Briefly explain what the procedure will involve using patient-friendly language.

If the patient is unresponsive, act in the patient’s best interests, as this is a life-threatening emergency.

Gain consent to proceed with applying a tourniquet.

Adequately expose the patient’s arms and legs as appropriate.

Applying an arterial tourniquet

1. Ensure scene safety and don appropriate PPE.

2. Expose the limb to locate the exact site of bleeding.

3. While preparing the tourniquet, apply firm direct pressure to the wound with gloved hands or a trauma dressing, or ask a colleague to do this.

• Consider indirect pressure with a knee or fist to compress the artery supplying the wound.

4. Place the tourniquet 5 – 7 cm above the bleeding site, avoiding joints. If the wound is not clearly visible, apply the tourniquet as high as possible on the limb.

5. Wrap the tourniquet band tightly around the limb, ensuring there are no twists in the strap. Position the windlass (or mechanical tightening system) where it is easily accessible.

• Ensure the tourniquet band is as tight as possible at this stage.

6. Tighten the tourniquet further using the windlass until bleeding stops; this may require significant force.

• A correctly applied tourniquet should suppress the distal pulse and be uncomfortable.
• The windlass should require only a half to a full turn. This is important so as not to allow continued venous bleeding through incomplete circumferential compression.

7. Secure the mechanism in accordance with the device’s instructions.

8. Record the application time clearly, either directly on the tourniquet or on the patient’s skin using a marker.

9. Do not cover the tourniquet with clothing or blankets if possible. Visual monitoring is essential.

10. Assess and document neurovascular status distal to the site, including capillary refill, pulse, sensation, skin colour, temperature, and motor function.^1-5

To complete the procedure…

Dispose of your PPE and other clinical waste into an appropriate clinical waste bin.

Wash your hands.

Document the details of the procedure, including:

• Application time
• Rationale for application
• Neurovascular findings
• Ongoing care plan ^{1-3, 5}

Aftercare and monitoring

Reassess the limb and monitor neurovascular status regularly.

Continue to monitor the patient closely for signs of shock and ongoing haemorrhage elsewhere.

Consider early administration of analgesia, as tourniquet application is often extremely painful and prolonged use can cause significant discomfort.

Remain alert for tourniquet failure, ischaemia, or the development of compartment syndrome.

Do not remove or loosen the tourniquet unless you are trained and authorised to assess bleeding control and manage any deterioration.

If extrication and conveyance are delayed, local policies may allow reassessment and conversion to haemostatic or pressure dressings, provided bleeding is controlled and the reassessment is performed by a competent clinician.

Communicate clearly during handover: time applied, limb and site, rationale, neurovascular status, response to intervention, and plan.^{1-2, 5}

Reviewer

Joshua Barker

Advanced Prehospital Practitioner

Editor

Dr Jamie Scriven

References

1. Lethbridge K, Pilbery R. Ambulance Care Essentials. 2nd ed. Class Publishing. 2019.
2. Chatfield-Ball C, Boyle P, Autier P, et al. Lessons learned from the casualties of war: battefield medicine and its implication for global trauma care. Journal of the Royal Society of Medicine. 2015. Available from: [LINK].
3. Joint Royal Colleges Ambulance Liaison Committee. Catastrophic Haemorrhage Control. In: JRCALC Clinical Guidelines 2024. p.112-117. Bridgewater: Class Professional Publishing. 2024. 
4. Joint Royal Colleges Ambulance Liaison Committee. PHEM Trauma Manual – JRCALC Supplement. Bridgewater: Class Professional Publishing. 2023.
5. NHS England. Clinical Guidelines for Major Incidents and Mass Casualty Events. London: NHS England Emergency Preparedness, Resilience and Response (EPRR) Programme. 2020. Available from: [LINK].