[New horizons in medicine. Complexity and predictability in internal medicine].

Being a highly sophisticated structure, the human body should be considered on a physical level as a whole of inter-correlated non-linear dynamic systems, which are by definition, complex systems because they are always conditioned in their operativity by numerous variables. We must draw attention to the opportunity that within the field of medical science the concept of complexity referring to diagnostic, therapeutic and prognostical problems, is distinct between structural and functional. The functional complexity of a system, a phenomena, an event, MY be recognized in its dynamics, only if analysed using modern methods recently brought to light, on the relationship which exist between classic determinism and deterministic chaos. Furthermore, also on practical level, the recent discoveries on the general principles, which are at the base of the functional complexity of non-linear dynamic systems, demonstrate exactly how fragile is the probabilistic predictability which guides a doctor in clinical reasoning in all its various stages; in the gathering of anamnestic and objective data; in the programming the researches aimed at confirming the validness of the diagnosis; in the therapy aimed at reaching the best possible results; in the prognosis which summarize the destiny of the binomial patient illness. The scientific enunciate of universal nature, which demonstrate how, from a tiny uncertainty in the initial functional data of a system, of a phenomena, of an event can unleash a condition of absolute unpredictability, find daily confirmation in both clinical and experimental medicine.(ABSTRACT TRUNCATED AT 250 WORDS)