What are the causes of third spacing?

Third spacing refers to the accumulation of fluid in the interstitial space, leading to edema. Common causes include conditions such as heart failure, liver cirrhosis, and kidney disease, which disrupt normal fluid balance. Additionally, trauma, infections, and inflammation can increase capillary permeability, allowing fluid to leak into surrounding tissues. Decreased oncotic pressure due to low protein levels, such as in malnutrition, can also contribute to this phenomenon.