Pulmonary embolism is the obstruction of a pulmonary artery or one of its branches, usually by a blood clot. It causes damage to the affected lung and the injured part can no longer supply oxygen to the body.
The clot forms during phlebitis or venous thrombosis (usually in the legs). It detaches from the wall of the vein and rises with the blood in the venous circulation towards the heart. During its contractions, the right ventricle of the heart propels the clot into the pulmonary arteries. The blood clot travels through increasingly fine arteries, where it ends up getting blocked.
The Geneva Score is a scoring system for determining the probability of the presence of a pulmonary embolism. In contrast to the Wells score, where one criterion is: "There is no other diagnosis that is more likely than a pulmonary embolism", the Geneva score explicitly made sure that all criteria are objectifiable.
The score obtained relates to the probability of the patient having had a pulmonary embolism (the lower the score, the lower the probability):
<5 points indicates a low probability of PE
5 - 8 points indicates a moderate probability of PE
>8 points indicates a high probability of PE