Is using laughing gas considered general anesthesia?

No: Nitrous oxide (laughing gas) still allows the person to breathe. General anesthesia usually results in the patient not being able to breathe on their own and needing a ventilator to support breathing. An anesthesiologist is also present during general anesthesia.

Yes : Yes in a strict sense it is. Use of nitrous oxide requires oxygen level monitoring and is a form of general anesthesia.

Yes: Use of nitrous oxide is general anesthesia. The fact that you still breath on your own is not the relevant factor.

Usually, yes: "laughing gas" is the slang term used sometimes for a gas called nitrous oxide. It is a weak anesthetic gas that is not usually enough to produce general anesthesia by itself. For surgery, it is used in combination with other gases such as sevoflurane or desflurane. In the dentist's office, it is sometimes given to supplement the local anesthesia that the dentist will use to numb the tooth.

Yes, but: This was one of the first agents that was used in anesthesia. However, in normal doses (that is non hypoxic) it is difficult to truly put you to sleep with it. This means we have to use other agents with it to provide true general anesthesia.