In the account of the murder of Kiyan Prince it was stated that he "was stabbed twice, once in the arm and once in the stomach", and there can be no doubt that it was the latter which was fatal (Hunt for expelled pupil as school mourns stab victim, May 20). In the adjacent Medical View column, surgeon Dr Andrew Murday said: "Stabs in the abdomen and even the groin can be fatal too." The deaths of Damilola Taylor and Special Police Officer Nisha Patel-Nasri testify to the truth of this statement.

Yet the lives of such stabbing victims and others like them might be saved by publicising principles now taught to all surgeons in training, and which can easily be applied by any member of the public.

One event changed forever my approach to the management of life-threatening injuries. A brilliant medical registrar was shot in the right lower back by his spurned lover during a party in the mess of our teaching hospital. A group of fellow doctors carried him down two flights of stairs to the casualty department, where he died soon after from haemorrhage shock. The bullet had severed the main artery to his lower pelvis and right leg, and his abdomen was filled with blood. When I heard of this a few days later I could not understand why the doctors who rushed to his aid failed to take a simple step to control the haemorrhage. He should have survived.

An experienced surgeon will instinctively know how to deal with unexpected bleeding; first, gain control above and below the wound before proceeding to deal with the problem. The skill is in knowing just where and how to gain control in a single movement.

If a large artery is severed by a stabbing in the groin or upper thigh, the torrent of blood released under pressure will be obvious externally. It is simple to staunch the haemorrhage by applying very firm pressure just above the injury: the victim must first be pulled out flat; then, kneeling on the same side as the injury, the first-aider uses a clenched fist to apply very firm pressure just above the wound and on a line between it and the belly button.

A second fist, applied to the abdomen just below the belly button, pushing the belly wall hard against the spine, can also be used if the bleeding seems unabated. This action compresses the main artery to the lower body and both legs. A tourniquet or bandage cannot achieve sufficient direct pressure to control bleeding from the large artery in the groin.

Should the stab wound be higher in the abdomen, and a vital organ or large artery lacerated, there may be little external bleeding but the life-threatening haemorrhage will continue as the abdo-minal cavity fills with blood. The only thing a first-aider can do is apply the fist pressure as high as possible, just below the breast bone, and trust some control can be achieved until expert help arrives.

If more people realise they have the power to save lives, then these tragedies could be dramatically reduced.

The golden rule is to stop the flow with your immediate effort, and hang on, no matter how tired you feel or how much discomfort you seem to be causing. Your reassurances to the victim that he or she will not die will be based on a very real likelihood that this will be true.

· Harry Espiner is a retired consultant general surgeon. Email: harry@espiner.com

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