Published online by Cambridge University Press: 16 March 2006
Bleeding in elderly patients is most commonly due to an underlying structural problem or an acquired coagulopathy. Occasionally, previously asymptomatic congenital bleeding disorders may present at an advanced age. When considering the possible causes of a clinical bleeding problem, the coagulation cascade is still a good starting-point. However, it is important to realize that the traditional model of the coagulation cascade has been superceded by the concept of a ‘coagulation network’. This updated model recognizes the importance of tissue factor in the initiation of coagulation. Despite the complexity of this model, the basic coagulation tests can still be interpreted in relation to the ‘intrinsic’, ‘extrinsic’ and ‘final common pathway’ components of the old-fashioned cascade (Figure 1).