Crystalloids, colloids, blood, blood products and blood substitutes

Understanding the physiology of fluid distribution within the human body is fundamental to the practice of anaesthetists and intensivists of all grades. There is a necessity to recognize the range of actions and consequences of the commonly infused intravenous fluids if safe patient care is to be provided. There are many historical and on-going trials surrounding fluid therapy and it is important for the physician to keep up to date with current guidelines. There is a continued drive to improve the safety of donor blood and prevent transfusion errors. Knowledge of how blood products are collected separated and stored is essential to prevent harm to patients through transfusions. Work in producing blood substitutes is progressing, but to date, trials have failed to market a product in Europe and the USA with an acceptable risk profile.