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Electrolyte Imbalance
Introduction
Edema is defined as the abnormal accumulation of fluid in the interstitial spaces of the
body's tissues due to an imbalance in fluid movement across capillary walls and this leads to
swelling. The fluid buildup in edema develops due to physiological mechanisms such as
increased capillary filtration pressure, reduced capillary osmotic pressure, heightened capillary
permeability, or blocked lymphatic drainage (Porth et al., 2019). Edema may be either localized
or widespread. Generalized edema often results from an increase in vascular volume where
swelling in the hands and feet can occur. In cases of starvation and malnutrition, edema occurs
due to an insufficient supply of amino acids needed for plasma protein production (Porth et al.,
2019). About one third of the anorexia nervosa patients develop edema (Gibson et al., 2020).
Edema caused by reduced capillary osmotic pressure typically results from insufficient
production or excessive loss of plasma proteins, primarily albumin (Porth et al., 2019).
Role of Albumin in Edema
The protein that was low in the anorexia patient’s blood is albumin. Albumin, the most
abundant protein in blood plasma, is produced by the liver. It is essential for maintaining osmotic
pressure, which helps retain fluids within the blood vessels. Albumin, due to its size and negative
charge, attracts water molecules and helps retain fluid within the bloodstream. In cases of severe
malnutrition, such as anorexia nervosa, protein intake is insufficient, leading to reduced synthesis
of albumin in the liver. A drop in albumin concentration lowers osmotic pressure, meaning the
