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Case histories
to the citizens of developing countries
throughout the world. Surgeons, anaesthetists
and nurses work in a voluntary capacity and
the organisation is funded by donation from
sources such as Rotary International, some
specific government funding and corporate
and private donors. Interplast Australia is a
non-profit aid organisation that has been in
existence since 1983 and sends voluntary
teams to 50 destinations in countries in the
Southwest Pacific and Southeast Asia. The
teams generally consist of 2 plastic and
reconstructive surgeons, 1 anaesthetist and one
theatre sister. The duration of the visits is two
weeks. Apart from surgery, teaching is undertaken
with the aim that the hospital staff will
become proficient in the techniques used.
2. Ever since their time in Saigon, Peter and
Pam Brown have taken their skills in plastic
and reconstructive surgery to many countries
in the Far East. It is therefore very appropriate
that their efforts have been formally recognised
by the Australian Government. Peter Brown
has been awarded the Australian Medal for
service to medicine, particularly in the field of
plastic and reconstructive surgery, and to
overseas medical aid programmes and they
have both received formal certificates from the
Australian Government for their contributions
towards assisting developing countries to reduce
poverty and achieve sustainable development
signed by the Prime Minister and the Minister
for Foreign Affairs.
Neostigmine-Glycopyrrolate and Antisnake Venom
for Management of Neuroparalytic Poisoning
20
Drs Shashi Kiran, Balbir Chhabra & Preeti Goyal
Department of Anaesthesiology and Critical Care
Post-Graduate Institute of Medical Sciences
Rohtak-124001, Haryana
India
Gupta3@vsnl.com
goyalpreeti@hotmail.com
Introduction
Envenomation by snakes of the Elapidae family,
commonly found in India, is characteristically
neuroparalyic in nature. The interesting
similarity of its electrophysiological features to
myasthenia gravis and the limited availability of
antisnake venom have prompted interest in the
use of anticholinesterese therapy.
Case Report
A 30 year old man presented in the Accident
and Emergency Department after being bitten
on the dorsum of his right foot by a snake. His
blood pressure was 160/100. pulse rate 92
beats per minute and respiratory rate 14 breaths
per minute with a good tidal volume. He had
dilated pupils, ptosis, generalised muscle
weakness and difficulty in swallowing but a
good cough reflex.
After first aid and the transfusion of
antisnake venom, he was admitted to the
Intensive Care Unit for observation. Within two
hours of admission, his respiration became
shallow and blood gas analysis showed a
respiratory acidosis. He was intubated and
artificial ventilation started. He was given
fifteen vials of antisnake venom over 12 hours
and neostigmine 2mg every four hours together
with glycopyrrolate 0.2mg. Over the next day,
his condition gradually improved and it was
possible to wean him from the ventilator after
72 hours. His muscle weakness resolved
completely, he was able to swallow, had a good
cough reflex and his pupil size returned to
normal.
Discussion
Envemonation by members of the Elapidae
family results in neuroparalytic features due to
the curare-like action of the venom. Ptosis is
usually the earliest paralytic manifestation
followed by involvement of the muscles of the
palate, jaw, tongue larynx and the muscles of
swallowing. The chest muscles and diaphragm
are involved later and cause respiratory failure
as occurred in our patient.
As well as general care and respiratory
support, antisnake venom (ASV) is generally
administered. ASV is a neurotoxin-specific
immunoglobulin that accelerates dissociation of
the neurotoxin/acetylcholine receptor complex.
Unfortunately there is no consensus on the
effective dose of ASV or indeed if it is of any
value whatsoever. In several trials, there has
been little or no change in morbidity or mortality
after ASV was used and there appears to be no
correlation between the dose of ASV
administered and the size or site of the snake
bite or the species of snake.
As snake venom can cause
pathophysiological features similar to
myasthenia gravis, neostigmine has been
suggested as an alternative therapy. Pandey et
al. first added neostigmine to conventional
treatment with ASV in 1969. They observed a
dramatic improvement in neuroparalytic
symptoms in 65 patients and recommended that
it should be administered to all patients with
paralytic symptoms. Moreover, Bomb et al have
recently condemned the use of ASV and
suggested that anticholinesterese drugs and
good supportive care are all that is necessary.
Neostigmine can be given as 50-100
micrograms/kg four hourly or as a continuous
infusion. Edrophonium has also been used in
doses of 10mg in adults and 0.25mg/kg in
children as a test and, if a positive response
occurs, converting to the longer acting
neostigmine. As there is no consensus on the
optimum treatment, we elected to use
neostigmine 2mg four hourly together with ASV.
Although atropine is often used before
neostigmine to counteract its muscarinic effects,
as it is a tertiary ammonium compound it
crosses the blood brain barrier. This can result in
a central anticholinergic syndrome with
confusion and prolonged muscle weakness. We,
therefore, decided to use glycopyrrolate as
unlike atropine, it does not cross the blood brain
barrier.
We are not sure whether ASV or
neostigmine resulted in the early favourable
outcome for our patient but their coadministration
certainly resulted in a rapid
neurological recovery. Therefore, we
recommend glycopyrrolate-neostigmine with
ASV for the management of patients with
neuroparalytic symptoms following snake-bite.