Converters
Aug 6, 2026
The Human Body Contains 42 Litres of Water — What Blood Volume, Lung Capacity, and Fluid Compartments Actually Mean Clinically
Losing 750 ml of blood (15% of total volume) is manageable — losing 1,500 ml is haemorrhagic shock, but rate matters as much as volume. Here's the ATLS haemorrhage classification by volume lost, the five lung volume subdivisions (TLC, VC, FRC, RV, tidal volume) and what each predicts in pulmonary disease, the 42-litre total body water distribution across intracellular and extracellular compartments, and why choosing the wrong IV fluid type (crystalloid vs colloid) worsens oedema while failing to restore plasma.