Imagine the scene.

You are out on the hill when a keen mountain biker comes hurtling past you. They’re doing well until their front wheel hits an unyielding rock and the rider is thrown from his saddle resulting in a traumatic accident.

You approach the casualty and observe that he is kneeling on all fours facing the floor coughing up blood. He has a sucking chest wound – possibly a brake lever has penetrated and exited from his chest. What are the considerations for outdoor first aid and this chest injury?

HM Coastguard attending to a call out on Crib Goch April 2017

What position do you place this (still conscious) casualty in?

Historically, if you who have been on a first aid course you will have been taught to lie the conscious casualty in a semi-recumbent position with the bad side down. If the casualty becomes unconscious – place them in a safe-airway position with the bad side down.

The thinking goes along the lines that the bad lung won’t bleed into the good lung. Another theory popularly expounded is that a casualty sat up leaning to one side allows the injured lung to still work while any fluid pools in its lower cavity.

This is actually physiologically flawed: your lungs are like two independent balloons. When there is a puncture to the outer chest wall, the blood will take the least line of resistance. Thus it will not take a convoluted pathway down through the bronchiole and into the airway but rather out and into the pleura cavity. Only if the wound is deep enough that blood enters the carina is this practice of having a chest injury down most practicable.

What is the best practice for this casualty then?

Place a casualty with a sucking chest wound bad side up. Why?

  1. Blood flows naturally and most easily with gravity. The casualty needs all the help he can get in getting what blood flow he has to the chest oxygenated. Hence this is best done with the good lung down.
  2. It’s painful lying on a chest injury – allowing it to be uppermost allows offers the most pain relief.
  3. With the injury uppermost it allows for better inspection, and monitoring.
  4. The ERC 2015 guidelines say that the wound should not be occluded. Placing the casualty with the bad side down may occlude the wound.

Further references

Here’s what the experts say …
2015 European Resuscitation Council Guidelines
 “First aid treatment for an open chest wound Leave an open chest wound exposed to freely communicate with the external environment without applying a dressing, or cover the wound with a non-occlusive dressing if necessary. Control localised bleeding with direct pressure.”

I have quoted here their guidelines – note they do not mention casualty position one way or the other.

2013 FPHC findings 2013
Another excellent source of guidance for first aid trainers is the Faculty for Pre-hospital Care. These are their findings based on a consensus of expert opinion and a review of the current literature.

“The optimal position for gas exchange is sitting up, or lying with the healthy lung down.3-6 This is unlikely to be possible in the case of patients who are hypovolaemic, in whom spinal fractures cannot be excluded, where lung injury has caused airway bleeding, or for practical reasons of safety during transfer.”

National Center for Biotechnology Information 2005

“Positioning – If placed on one side this should be good side down as ventilation–perfusion is optimal one third up the chest. If there is a risk of airway contamination (blood in the airway or vomiting) then the injured side of the chest should be positioned down.

Consider lying the patient on the side of a flail to allow splinting and analgesia.

If there is an anterior flail chest then manual splinting of the chest may need to be maintained

Note that the ability to reposition is limited in a moving ambulance

In an isolated chest injury the ideal position is sitting up. Patients self‐splinting using their own chest muscles will be reduced if they lay flat. Avoid long periods positioned supine on a spinal board. If the patient is conscious, with no neck pain and no distracting pain or injuries, patients who wish should be allowed to sit up.

Unconscious patients with the appropriate mechanism of injury should have full spinal immobilisation.”

But …

These references point to best practice for pre-hospital care medics and technicians. What if the casualty is bleeding into the airway? What if the injury is internal (ie occluded by the skin)? What if there is trauma to the spine?

Because there is not a simple solution to all cases, and because we want to provide guidance to our course delegates for what is safe practice for most casualties in most situations – we will continue to teach what is currently advised in the manual: for an unconscious casualty with a chest injury, place them bad-side down. We will teach this because we accept the limitations of the first-aider.

More articles on Outdoor First Aid

Will Legon (of works professionally in the outdoors leading groups walking and instructing single pitch rock climbing. Since 2009 Will has been delivering first aid training specialising in outdoor first aid courses. He is an ITC (Immediate Temporary Care) trainer, offering a range of courses accredited by Ofqual and the SQA. In a former life, Will was a maths teacher and an infantry officer in the Territorial Army.

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