Every hiker should have at least a basic knowledge of first aid and three of the most valuable skills that you can learn are carrying out CPR, performing the Heimlich maneuver and dealing with fractures.

This doesn't mean of course that you're likely to have to use these skills frequently and most hikers will never need to use them at all. Nonetheless, it's a good idea to be prepared because if you find yourself with a companion who is choking to death while you sit eating your evening meal by the campfire in the middle of nowhere, the Heimlich maneuver might just be a life saver.

CPR

Cardio-pulmonary Resuscitation is a technique used to re-start normal breathing and, while this is a fairly easy technique to learn, it is something that you need to learn at the hands of a skilled professional. There will almost certainly be classes available in your local area and your local hiking club will almost certainly either provide training for its members on a regular basis or have details of classes that you can attend. Such classes are normally quite short and are almost always free of charge.

If you find yourself with someone who is not breathing and you are able to do so you should call 911 or a local rescue team immediately and also shout loudly for help. You never know who is hiking on the trail near you and there might just be expert help close at hand.

Try to determine the cause of the problem. If the person concerned was swimming and needed to be dragged out of the water then you may need to clear water from their airway before you can start CPR. In this case, put them on their stomach and try to remove water by modest, short compression on the diaphragm, located above the stomach and below the chest.

Next, roll them onto their back and pinch the nose. Breath into the mouth, covering their mouth with yours and watching out of the corner of your eye for chest expansion. Then let go and tilt the body to allow for the expulsion of water. Repeat, giving two breaths of two seconds each.

If that has no effect, you should try chest compressions. Push down firmly along the sternum above the diaphragm. Repeat this five times, about once per second, and alternate between chest compressions and inflating their lungs.

The Heimlich maneuver

Food or other obstructions can interfere with breathing and the Heimlich maneuver is designed to remove foreign objects from the air passages.

Start by looking for obstructions in the throat which can be quickly and easily removed. If nothing is immediately visible then stand the person up and position yourself behind them. Put your arms around their body and grasp one wrist with the opposite hand so that the bone at the base of your thumb is against their body and just under the ribcage. Make sure that the person's head is tilted forward and down enabling gravity to work with you rather than against you.

Give a sharp, short, firm jerk inward against the diaphragm and repeat this several times if necessary watching for the object to dislodge. Be careful to insure that your hands are below the ribcage and pressing on the diaphragm and not the ribcage.

Bone fractures

Fractures can vary from a relatively minor and invisible toe break, which simply makes walking painful, to quite serious compound fractures and you should seriously consider taking a professional first aid course to enable you to deal with fractures. In advance of this, here are some general guidelines.

The most serious form of fracture is a compound fracture in which the bone is protruding from the skin. In this case, not only is the bone badly broken, but the rupture of the skin leaves an opening which is prone to infection.

Do not try to straighten the fracture but simply cover the wound with sterile gauze and get professional help as quickly as possible. If it is necessary to immobilize the limb, apply a splint to keep it at the same angle.

Get hold of a straight stick or use a piece of walking pole or other straight, rigid object and pad the splint well before wrapping it with an elastic roll bandage or medical tape. In the absence of supplies, look for a thin, strong vine to tie the splint to the limb and tie it firmly enough to hold it, but not so firmly that you cut off the blood supply to the limb.

In all cases, abandon your hike and seek professional medical help as quickly as possible.