Anaesthetics
Cosmetic Surgery - Plastic Surgery - Aesthetic Medicine - Reconstructive Surgery
The ether was the first anaesthetic to be synthesized; this synthesis was carried out by Cordus Valerius (1515-1544). This substance was first tested in chickens by Paracelsus (1493-1541); it was not until the mid-nineteenth century (1846) when ether was used to anesthetize a patient. It was a student, William T.G. Morton of the Harvard Medical School who used this anaesthesia in order to provoke a state of insensibility for the purpose of conducting surgery. Anaesthesia is defined by loss of sensation.
There are local anaesthetics and general anaesthetics.
Local anaesthesia temporarily suspends sensitivity in one or more parts of the body in order to perform surgery or an examination. The most effective local anaesthetic until the mid-twentieth century was cocaine, directly extracted from the leaves of the tree of the same name from the Andes.
In 1948, lignocaine or lidocaine was marketed under the name of Xylocaine. Today this is the most widely used local anaesthetic. Related derivatives have been released onto the market.
Their administration is by injection close to the spinal cord, in the cerebrospinal fluid (spinal anaesthesia) or around the duramater (epidural anesthesia).
General anaesthetics are administered in two ways: intravenously (hypnotics and adjuvants) and by inhalation (mixture of oxygen and anaesthetic gas).
The main property of a hypnotic is to lead to a deep sleep. Intravenously administered hypnotics are fast-acting barbiturates.
Benzodiazepines injected intravenously may cause a more or less pronounced state of sedation and also be used as additives to the above.
The gaseous agents used have a variable degree of anaesthetic power. Nitrous oxide is used as are so- called "halogenated" agents which are more powerful and thus used at concentrations much lower than nitrous oxide... During anaesthesia these gaseous agents are mixed with oxygen.
To these hypnotic agents should be linked:
-analgesics whose role is to eliminate or reduce sensitivity to pain. Opiates or equivalents that are synthetic or semi-synthetic derivatives of opium are used...
-neuromuscular blocking agents that cause controlled muscle paralysis to facilitate surgical procedures (oro-tracheal intubation) when muscle relaxation is needed.