Amanda is an 18-year-old with anorexia nervosa. She was recently admitted to an eating disorders clinic with a BMI of 13.9, and although she was a voluntary patient, she was reluctant about the treatment. She was convinced she was overweight because her clothes felt tight on her. She complained that even her hands and feet “were fat.” One of her nurses explained that a protein in her blood was low. The nurse further explained that, as difficult as it may be to believe, eating a normal healthy diet would make the “fat hands and feet” go away.
- What protein do you suspect the nurse was referring to? How would a deficiency in this protein contribute to edema?
- What is the difference between the physiology of pitting and nonpitting edema?
- Because of her weakened condition, Amanda was moved around the ward in a wheelchair when she was not on bed rest. How does this affect her edematous tissues?
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Introduction:
This question is related to the case of an 18-year-old girl with anorexia nervosa who has been admitted to an eating disorders clinic. The question focuses on the understanding of proteins and edema, the physiology of pitting and nonpitting edema, and the effect of being moved around in a wheelchair on edematous tissues.
1. The nurse referred to the protein albumin, which is a protein that helps maintain plasma oncotic pressure in the body. A deficiency in albumin can cause edema because it leads to decreased plasma oncotic pressure, which results in the accumulation of fluid in the interstitial spaces. Therefore, low levels of albumin in the blood can cause fluid to leak out of the blood vessels and accumulate in the tissues, leading to edema.
2. Pitting edema occurs when pressure is exerted on swollen tissue, and a persistent indentation, or “pit,” remains after the pressure is released. Nonpitting edema, on the other hand, is characterized by swelling that does not leave a persistent indentation when pressure is applied. The main difference between them is in their physical characteristics. Pitting edema is commonly caused by conditions such as heart failure, liver disease, or kidney disease, whereas nonpitting edema is associated with conditions such as lymphedema or lipedema.
3. Being moved around in a wheelchair can worsen edematous tissue by further impairing lymphatic and venous circulation. When the body is immobile, the lymphatic system is less effective in removing excess fluid and protein, resulting in more edema. In addition, the use of a wheelchair can increase the pressure in the blood vessels, leading to increased blood flow and a further accumulation of fluid in the tissues. Therefore, it is essential to monitor edema in patients who are inactive, and regular movements are required to promote lymphatic and venous circulation.
