Pathophysiological changes of ageing and their relevance to anaesthesia
The molecular basis of ageing is reviewed. This includes the concept of a summation of DNA damage over a lifetime causing genome instability. Epigenetic alterations, telomeric shortening, and the possibility of their modification are discussed. Oxidative and mitochondrial DNA damage and the resulting dysfunction leading to senescence are briefly described. Systemic problems and resultant behavioural adaptation may mask the decline in functional reserve and cause some of the difficulties in identifying its presence in ill elderly patients. Specific organ system changes are then described in some detail. These include the major concerns with the cardiovascular, respiratory, renal, hepatic, neurologic, endocrine, and musculoskeletal systems. The effect of ageing on the special senses of vision and hearing are covered, with emphasis on issues of informed consent.