[libribook.com] Traumatic Scar Tissue Management 1st Edition

Edema
Edema – the medical term for swelling – is considered to be a symptom. Edema
can occur as a natural response of the body to injury or insult. Increased fluid in
the affected area can be beneficial by assisting the delivery of immune cells to
the area to fight an infection and assist with debris cleanup.
Edema can be isolated to a small area (localized) or can affect the entire body
(generalized).
Pregnancy (preeclampsia or toxemia), tissue trauma, infections, medications and
various conditions can result in edema; for example, venous insufficiency,
obstruction of flow (e.g. thrombosis, tumor), low albumin, allergic reactions,
congestive heart failure, liver and kidney disease, and critical illness (WebMD
2015).
Medications known to result in lower extremity edema include non-steroidal
anti-inflammatory drugs (NSAIDs), corticosteroids and some medications used
for hormone replacement, diabetes, depression and high blood pressure (WebMD
2015).
Discussion of the role of edema in critical illness, such as a burn or surgery, will
be discussed in Chapter 5.
How the Body Responds to Edema
When there is an increase in the lymphatic load of water and proteins, the lymph
system responds protectively with either active or passive edema.
Passive edema protection (Zuther 2011) is an increase in the volume of water
leaving the blood capillaries. This is followed by an increase in the volume of
fluid in the interstitial tissue, which creates pressure in the tissue. This pressure
increases net reabsorption pressures, which assists edema protection.
In active edema protection (Zuther 2011), the lymphatic system responds to the
increase in the lymphatic load of water and protein by elevating the contraction
frequency in the lymph collectors and lymph trunks. The increase in fluid
pressure stimulates the smooth muscle inside the wall of the node, which
increases contraction frequency and volume in the node.