If it is general anesthesia then the individual has to be in a state of fasting for a certain period of time but the immediate requirements of hydration are met through intravenous infusions. The requirement for water and minerals ranges from saline fluids to Hartmann's solutions depending upon the severity of the physical condition and duration of the illness and period of remaining in a state of nothing per orum (NPO).
Apart from the physical condition and the severity of the disease, climate also plays an important role in determining and maintaining the body requirements for hydration. A hot and dry climate demands some additional volumes of fluids to be infused other than what has been calculated. Comparatively, in a cold and humid atmosphere, the fluids requirement may need just the replacement of 24 hours needs based on excretion and perspiration if any exist.
Gender may not be an important determining factor but the extreme of age and size of the body influence the daily needs of the individuals who are o fluids. Calculations for fluid requirements in paediatrics category is strictly based on body weight as compared to rough estimation in adults. Also, elderly patients need to be replaced with fluids with care. Similarly, monitoring fluid intake and output may need some judicious efforts as compared to healthy and adult individuals. ...Show more