Acute care: Volume resuscitation
In the third part of our acute care series,Nicola Cooper explains volume resuscitation Normal versus abnormal fluid needs
Doctors learn about average daily fluid needs at medical school, but often little is taught about fluid needs in illness. The average 70 kg person needs about 3 litres day to cover insensible losses and the necessary intake to maintain normal fluid balance. But the patients we deal with are physiologically stressed through illness, and this dramatically alters the volume and composition of the intracellular and extracellular spaces as well as the kinetics of fluid distribution and excretion.
Patients may have increased fluid losses through fever, dehydration, bleeding, or breathlessness. An extra 500 ml of fluid a day is needed for every degree above 37°C. Gastrointestinal losses are often underestimated, particularly in patients with diarrhoea or bowel obstruction. Some conditions cause capillary leak syndrome, in which serious intravascular volume depletion occurs with peripheral and pulmonary oedema--severe pancreatitis and sepsis are examples. It can get complicated.
To preserve plasma volume after