Whitehead’s varnish in gauze is used to arrest bleeding from
**Core Concept**
Whitehead's varnish is a type of hemostatic agent used to control bleeding from wounds. It is a mixture of ferric subsulfate and resin, which polymerizes on contact with the tissue fluid, forming a gel-like substance that helps to stop bleeding.
**Why the Correct Answer is Right**
Whitehead's varnish works by polymerizing and forming a gel-like substance that fills the capillary vessels and prevents blood from flowing out. This process is known as coagulation. The ferric subsulfate in Whitehead's varnish reacts with the tissue fluid to form ferric ions, which then cross-link with proteins to form a network of fibers that helps to stop bleeding.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because Whitehead's varnish is not a topical anesthetic. While it may provide some analgesic effect, its primary use is as a hemostatic agent.
* **Option B:** This option is incorrect because Whitehead's varnish is not used to treat burns. It is specifically designed to control bleeding from wounds.
* **Option C:** This option is incorrect because Whitehead's varnish is not a type of antibiotic. It does not have any antimicrobial properties.
**Clinical Pearl / High-Yield Fact**
Whitehead's varnish is a classic example of a hemostatic agent that can be used to control bleeding from wounds. It is a simple and effective way to stop bleeding, and it can be used in a variety of situations, including emergency medicine and surgery.
**Correct Answer:** B.