Which of the following is used in anesthesia ?

Options

A. `N_2`
B. `N_2O`
C. `CH_4`
D. `CO_2`

Answer

To answer the question "Which of the following is used in anesthesia?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand Anesthesia**:
- Anesthesia is a medical procedure that induces a state of unconsciousness or insensitivity to pain during surgical procedures.

2. **Types of Anesthesia**:
- There are different types of anesthesia, including general anesthesia, local anesthesia, and regional anesthesia. General anesthesia is used to render a patient unconscious.

3. **Administration Methods**:
- Anesthesia can be administered in two primary ways:
- **Inhalation**: Through a breathing mask.
- **Intravenous (IV)**: Through an intravenous line.

4. **Common Anesthetic Agents**:
- One of the commonly used anesthetic agents is **Nitrous Oxide (N2O)**, which is a weak general anesthetic.
- It is often used in combination with oxygen, typically in a concentration of 70% Nitrous Oxide and 30% Oxygen.

5. **Conclusion**:
- Based on the information, Nitrous Oxide is a substance used in anesthesia, particularly in a combination with oxygen for surgical procedures.

### Final Answer:
- **Nitrous Oxide (N2O)** is used in anesthesia.