in other areas, anesthesia for laser treatment
must be appropriate for the particular therapy
and ensure safety and minimum discomfort. It must
also keep pace with rapidly advancing laser techniques
which have newer applications needing a variety
of anesthesia. Some of the anesthesia techniques
and the methods of administering them are discussed
Cryoanesthesia - the use of cold to anesthetize
is an old topical treatment. Cold works like
local anesthesia, first blocking pain fibers,
then thermal fibers and finally tactile fibers.
Refrigerant sprays are fast acting but last few
seconds. Ice packs are cheaper, easily available
and somewhat longer acting.
A local anesthetic or a eutectic mixture local
anesthetic cream (EMLA) is preferred in the painful
tattoo treatment by those who cannot tolerate
it without anesthesia or with ice packs. EMLA
is not advised in infants for more than a month,
though it can be used successfully in children
for treating port wine stains. The effect of
EMLA is not uniform. Very few children under
10 tolerate their treatment using EMLA. Its use
is now restricted to adults and adolescents.
The non-uniform effect of EMLA can be improved
by adding local infiltrative anesthesia and the
efficacy can be improved by adding an oral sedative.
Infiltrative anesthesia administered intradermally
or subcutaneously, is very common way to anesthetize
skin. It acts quickly and the effect lasts from
30 to 120 minutes. Being an amide, chances of
allergic reactions are less compared with ester
anesthetics. Lidocaine is a common and safe anesthetic,
if the dosage is not exceeded. For long duration
treatments long acting anesthetic like bupivacaine
Peripheral nerve blocks can be produced by administering
a local anesthetic along a nerve trunk, which
has many nerves branching out. This way, large
areas of the skin can be anesthetisized by a
small amount of anesthetic which, besides, causes
less pain and carries less risk of toxicity.
Sometimes, when nerve blocks are difficult to
produce, local anesthetic is added.
Oral sedation is helpful in laser treatment
for children, who have low pain tolerance. Chloral
hydrate and midazolam are commonly used. These
sedatives may be used to control the children,
but will not provide any relief from pain since
they are not analgesia. Some physicians have
not found chloral hydrate particularly helpful.
Children importantly, need to be monitored for
any cardiopulmonary problems, especially with
The other ways of administering analgesia and
sedatives are the intramuscular, intranasal and
rectal routes. Drugs for intra muscular and intranasal
routes include midazolam and ketamine. Methohexital
is used for the rectal route. Since these drugs
are rapidly absorbed by these methods, it is
important that an anesthesiologist be present.
Oral diazepam may be given to anxious adults,
especially for CO2 resurfacing, which uses EMLA,
nerve blocks and local infiltrates as anesthesia.
An oral narcotic analgesic may also be given
to reduce pain.
Intravenous sedation is employed where the laser
treatment is painful. It is also preferred where
the size and location of the treatment site is
such, that easy anesthetizing is not possible
by other methods. The drugs generally used are
the narcotic fentanyl and the tranquiliser midazolam.
Since these drugs are very potent, their use
must be strictly left in the hands of experienced
people. In the hands of inexperienced people
the result may be lethal. There are reports of
several deaths in such and similar cases. Presence
of experienced anesthesiologist or anesthetist
during the treatment should be mandatory.
General anesthesia may be the only choice for
treating vascular lesions in children. Reasons
include location of the lesions on the face,
the lesion size, multiple treatment sessions
and the immaturity of the patients. As important,
is that early treatment gives a good chance to
the lesions to clear quickly and completely.
Delayed treatment reduces the chances of complete
recovery. According to a group of physicians
parents preferred this treatment. Normally, general
anesthesia is not used on children before they
are 6 months old.
As multiple sessions are usually needed, the
anesthetic technique should be custom designed
for each child and the same treatment repeated.
The child should return to normal quickly with
least discomfort and side effects. Importantly,
the presence of parents helps the child to cope
with the treatment. General anesthesia is also
used in some cases of full face resurfacing with
The use of general anesthesia in laser treatment
for skin lesions carries the risk of fire, especially
in people with dark hair which absorbs more laser
energy. Fire risk can be minimized by wetting
the hair and preventing leakages of inflammable