Occasionally we meet with patients who have concerns about anaesthesia. Sometimes they are concerned about giving up control and being completely asleep without knowing what’s happening. Some of them have heard or read stories about people having bad experiences with anaesthesia. The following is a brief description of the differences between the three types of anaesthesia and how to choose the right anaesthesia for your procedure.
Drugs are given intravenously to make you relaxed, all anxieties you may have will disappear, and you will slowly drift off to sleep. Once asleep, a breathing tube is gently placed through your windpipe through which oxygen and some anaesthetic drugs in gas form are given to you. Your vital signs, oxygen and carbon dioxide levels are continually monitored for your safety. General anaesthesia affords you the following: no perception of pain, no recollection of the period of time between when you go to sleep and when you wake up, muscle relaxation and a peaceful sleep. Your airway is protected via the breathing tube and the muscle relaxation is important to reduce post-operative discomfort and facilitate the surgery (the muscles are not resisting the surgeon’s efforts).
Medication is injected into the surgical site to make the tissues numb – so that the pain nerves in the tissues do not work. This will not afford you any degree of relaxation. For larger surgeries, it can be difficult to use local anaesthesia because there are limitations as to how much of the anaesthetic drug you can receive before toxic doses are reached.
Local anaesthesia + Sedation (oral or intravenous)
Local anaesthesia is given as above, but also sedation is given to relax you. If sedation is given, you should be monitored by an anaesthesiologist or nurse anaesthetist as over sedation can cause you to stop breathing on your own. Proper monitoring would prevent this or at least allow immediate intervention should this be required. Sometimes if local + sedation is not working well (difficulty keeping the level of sedation at the right level), then the patient can be converted to general anaesthesia.
The decision as to what is safest and effective is made between patient, surgeon, and anaesthesiologist. Less invasive, shorter procedures often are performed under local anaesthesia alone. More invasive, longer procedures often are performed under general anaesthesia. That said, some patients need sedation to tolerate a less invasive, shorter procedure, and some patients have larger operations performed under local. Often a combination of local anaesthesia and sedation is used. Again it requires careful consideration and planning to decide what is best for the patient.