The Mysterious World Of
Anaesthesia
1.
The thought of
undergoing surgery sends shivers down the spine of every one, be it poor or
downtrodden or rich and mighty. Only difference is some people express it very
explicitly and surgical team has a tough time controlling them on operation
table while some control their fears quite rationally, but that fear is there
lurking behind. If we analyse some common fears, they are:-
(a)
I will not become unconscious.
(b)
I will never wake up.
(c)
I will wake up in middle of the
surgery.
(d)
I will have lot of pain.
(e)
I will die.
(f)
I will end up being a vegetable
for life.
2.
Almost all if not all of these
fears of patients are tackled by your Anaesthesiologist. He conducts a thorough
Pre Anaesthetic check-up and assesses all your systems and if required
optimises your system to perform at their best before he agrees to take you up
for surgery. Under Anaesthesia all the protective reflexes of the body are
knocked off by the Anaesthesiologist to make the surgery possible and then he takes
over those protective actions himself to sustain life. The patient is made
unconscious, he is paralysed so that Surgeon can get access to the abdomen or
any other part required. He then has to take over the vital function of
respiration to sustain his life and also take measures to ensure stomach
contents don’t get into respiratory track and lungs and endanger his life.
Depending on the type of surgery he has to control the temperature, blood
pressure, circulation and many other systems as the requirement arises. For example
in open heart surgery, all the blood of the patient is diverted to a heart-lung
machine bypassing the heart, body temperature is lowered to reduce the
metabolic demands of the body, heart is then stopped and operated upon and then
body temperature is raised again, blood is diverted back to the heart and heart
is coaxed to start beating again and gradually the support of heart-lung
machine is withdrawn. During surgery especially under General Anaesthesia,
Anaesthesiologist has to practically live the life of the patient for him/her
during the surgery till he is in a condition to live it himself/herself. The
only time in life when an individual is more dependent on someone else for his
life is probably when a baby is in her mother’s womb.
3.
Over the years the field
surgery has made lot of advances. Earlier organ transplants were restricted to
only Eyes (Cornea) and Kidneys but now so many organs are added to this list
like liver and even Heart and Lungs. Surgery could not have advanced to the
extent it has if Anaesthesia services didn’t advance to keep pace and support
the rising demands made on the patient by the complex surgeries. The life of a
patient can be taken as a spectrum, one end of which has bright light with
fully conscious individual with all systems functioning optimally and the other
end has total darkness and death. Anaesthesiologist takes the patient to the
twilight zone before the darkness of death, keeps him there during the surgery
and brings him back to the sunshine of life after the surgery. This expertise
of the Anaesthesiologist which he practises daily during surgery is also
utilised in critically ill patients in the ICU where patients come after
reaching this twilight zone because of their illness. Next time when you go to
see your Anaesthesiologist, go with the knowledge that you are actually going
to give your life to him for safe keeping during the surgery and he will be
your guardian angel during the surgery.
4.
There are mainly two types of
Anaesthesia. General Anaesthesia and Regional Anaesthesia. The General
Anaesthesia has been described briefly above. We know that most of the nerves
of the body are transmit the motor and sensory signals to and from the brain
through the spinal cord passing through the vertebral column at the back. When
local anaesthetic drug is injected around these nerve bundles, it blocks the
transmission of signal transmission through them leading to anaesthesia of only
the part/region being supplied by that nerve bundle. This is Regional
Anaesthesia. The major advantage is that patient is not unconscious, he is
breathing on his own, his protective reflexes are not knocked off i.e. he
continues to live his life himself leading to greater safety. The farther we go from the brain to block these nerves the better it is for the patient as the side effects caused by the blockade of these nerves reduces. Like blockade of the spinal cord which is called spinal anaesthesia which is done by putting a needle through the gaps in-between the bones of the vertebral column. By this only lower half of the body becomes numb. It also causes some drop in blood pressure which is tackled by the Anaesthesiologist. If the nerves are blocked after they have come out of the vertebral column, there is no drop in blood pressure and the area becoming numb becomes smaller depending on the area covered by that nerve or by the bunch of nerves also called plexus which has been blocked.
