Integument Flashcards
What is interstitial oedema?
Increase in interstitial fluid volume due to an imbalance between microvascular filtration, lymphatic removal, and serosal transudation.
What are some causes of interstitial oedema?
- Heart failure
- Venous thrombosis
- Protein-losing disorders
- Excessive crystalloid administration
- Anaphylaxis
- Burns
- SIRS/extreme inflammation
What are the consequences of interstitial oedema on the lung?
Decreased compliance and gas exchange.
How does interstitial oedema affect the brain?
Increased intracranial pressure and neurological damage.
What is the primary regulator of interstitial fluid balance?
Interstitial fluid pressure.
What equation is used to explain capillary filtration?
Starling-Landis equation.
What does Jv represent in the Starling-Landis equation?
Microvascular filtration rate.
What is the role of the endothelial glycocalyx?
First barrier to filtration.
What is the significance of the osmotic reflection coefficient (σd)?
It indicates capillary protein permeability, ranging from 0 to 1.
True or False: Filtration occurs only at arterioles and reabsorption occurs only at venular ends.
False.
What is the role of lymphatic drainage?
Removal of interstitial fluids and return to venous circulation.
What are the determinants of lymphatic flow?
- Pint (Interstitial hydrostatic pressure)
- Ppump (Effective pumping pressure)
- Psv (Systemic venous pressure)
- RL (Effective resistance to lymph flow)
What mediators influence lymphatic contraction?
- Prostaglandins
- Thromboxane
- Nitric oxide
- Epinephrine
- Acetylcholine
- Substance P
- Bradykinin
Fill in the blank: Increased interstitial hydrostatic pressure opposes microvascular filtration by reducing _____ pressure.
Net filtration
What is SC emphysema?
Air trapped beneath skin within soft tissues.
What are typical causes of SC emphysema?
- Traumatic (e.g., bite wounds, chest trauma)
- Iatrogenic (e.g., endotracheal tube overinflation)
- Infectious (e.g., gas-producing bacteria)
- Spontaneous (e.g., unclear causes)
What is the Macklin effect?
Alveolar rupture leading to air entering pulmonary interstitium and causing pneumomediastinum and SC emphysema.
What is the gold standard for diagnosing SC emphysema?
CT scan.
What is the typical clinical presentation of SC emphysema?
- Recent intubation
- Trauma
- Coughing
What treatment is recommended for mild SC emphysema?
Self-limiting, no treatment needed.
What is the role of oxygen in the treatment of SC emphysema?
Reduces partial pressure of nitrogen, facilitating nitrogen washout from alveoli.
What is the purpose of VAC therapy in SC emphysema treatment?
To manage wounds and facilitate healing.
What can lead to tension pneumothorax in SC emphysema?
Space-occupying effect and pressure in fixed space increases.
What are the limitations of increased lymphatic flow as an antiedema mechanism?
Compensation decreases over time; venous hypertension impairs lymphatic drainage.
