Twilight anesthesia

Twilight anesthesia is an anesthetic technique where a mild dose of general anesthesia is applied to induce anxiolysis (anxiety relief), hypnosis, and anterograde amnesia (inability to form new memories). The patient is not unconscious, but sedated. During surgery or other medical procedures, the patient is under what is known as a "twilight state", where the patient is relaxed and "sleepy", able to follow simple directions by the doctor, and is responsive. Generally, twilight anesthesia causes the patient to forget the surgery and the time right after. It is used for a variety of surgical procedures and for various reasons. Just like regular anesthesia, twilight anesthesia is designed to help a patient feel more comfortable and to minimize pain associated with the procedure being performed and to allow the medical practitioner to practice without interruptions.

Twilight anesthesia is commonly known as twilight sleep and calls for an easy awakening and speedy recovery time by the patient. Anesthesia is used to control pain by using medicines that reversibly block nerve conduction near the site of administration, therefore, generating a loss of sensation at the area administered. Close monitoring by the anesthesiologist will sometimes be provided, to help keep the patient comfortable during a medical procedure, along with other drugs to help relax the body. It can also help control breathing, blood pressure, blood flow, and heart rate and rhythm, when needed.

There are four levels of sedation by anesthesia.

This level called Minimal sedation causes anxiolysis, a drug induced state in which the patient responds normally to verbal commands. Although the cognition and coordination of the patient are impaired, cardiovascular and ventilatory functions remain unaffected.

In this level called Moderate sedation/analgesia or conscious sedation, a drug induced depression of consciousness during which the patient responds purposefully to verbal commands, either alone or accompanied with light physical stimulation. Breathing tubes are not required for this type of anesthesia. This is Twilight Anesthesia.

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