The anaesthetist keeps the patient in a state of controlled unconsciousness during surgery. They do this with drugs which block the nerve signals to the brain, so that the patient cannot feel anything during the operation. This is what we mean when we say a patient is ‘anaesthetised’, or ‘put under’.
The anaesthetist also administers muscle relaxants to the anaesthetised patient. The muscle relaxants keep the patient’s body relaxed so they can’t move during surgery. This makes it easier for the surgeon to operate safely but it also affects the patient’s ability to breathe. Whilst the patient is unable to breathe, the anaesthetist uses a ventilator machine which breathes for the patient by passing oxygen through a tube which must be properly fitted into their airway (trachea).
The anaesthetist must monitor the patient throughout the operation, for example, to check their blood pressure, heart rate, respiratory rate and that the patient is receiving the correct amount of oxygen.
They must be alert to warning signs of complications, including any sign that the patient is becoming conscious or feeling pain, or is losing too much blood and needs fluid, or is suffering from some other complication or reaction. If a warning sign appears, they must react quickly to correct the problem. In the case of a severe allergic (anaphylactic) reaction this may mean stopping the operation.
They use a lot of equipment, including ventilators, monitors and alarms, to oxygenate the patient, administer drugs, fluids and gases, and monitor their vital signs.
They are responsible for checking the equipment before and during the operation and noticing if the equipment is not working properly from a fault, a blockage or, in the case of a tube, if it has not been properly fitted or secured or has been knocked out of place.
After surgery they are responsible for ensuring that the patient recovers consciousness and is able to breathe safely and for ensuring that the patient has come through the anaesthetic without any serious ill effects.
When a patient is treated under local or regional anaesthetic, (such as a spinal or epidural) the anaesthetist must use their skill, judgment and correct technique when administering the anaesthetic to avoid serious injury to nerves, such as paralysis, or other serious reactions, such as anaphylaxis.