Hypotension
Hypotension can have a number of causes, particularly loss of circulating volume
due to haemorrhage and vasodilation due to the action of the venom or direct effects
on the heart. Test for hypovolaemia by examining the blood pressure lying down and
sitting up, to establish postural hypotension. Usually crystalloids are used for volume
expansion. However, there is no conclusive trial evidence to support a preference for
colloids or crystalloids.
In cases where increased generalised capillary permeability has been established,
a vasoconstrictor such as dopamine can be used, dose being is 5 – 10μ /kg/minute
in normal saline or glucose solutions as IV drip. The fl ow rate may be adjusted to
maintain blood pressure adequately. Rarely Russell’s Viper bites are known to cause
acute pituitary and / or adrenal insuffi ciency. This condition may also contribute to
shock. Hence, this entity has to be remembered while dealing with hypotension in
snakebite as these cases require long term follow up.
Persistent or Severe bleeding
In the majority of cases the timely use of ASV will stop systemic bleeding. However
in some cases the bleeding may continue to a point when further appropriate treatment
should be considered. The major point to note is that clotting must be re-established
before additional measures are taken. Adding clotting factors, fresh frozen plasma(FFP), cryoprecipitate or whole blood in the presence of un-neutralised venom will
increase the amount of degradation products with the accompanying risk to the renal
function. Plasmapheresis has been used successfully in such situation.
Renal Failure and ASV
Renal failure is a common complication of Russell’s viper and Hump-nosed pit viper
bites. The contributory factors are intravascular haemolysis, DIC, direct nephrotoxicity,
and hypotension and rhabdomyolysis.
Renal damage can develop very early in cases of Russells Viper bite and even when
the patient arrives at hospital soon after the bite, the damage may already have been
done. Studies have shown that even when ASV is administered within 1-2 hours after
the bite, it is incapable of preventing ARF. Declining renal parameters require referral
to a higher centre with access to dialysis. Peritoneal dialysis could be performed in
secondary care centres.
Surgical issues
The surgical issues observed in snake bite cases are
• Ulcer following snakebite
• Necrosis of the skin and underlying tissues
• Gangrene of the toes and fi ngers
• Debridement of necrotic tissues
• Compartment syndrome and others
Practitioner while dealing a case of snake bite with one or other surgical
issues has been informed to remember the following and keep the patient
and the care givers accordingly.
Fasciotomy does not remove or reduce any envenomation.