4
- complicated by CV failure
p.
Seizures: probably due to hypotension and hypoxia
q.
Coma: usually sensorium is clear
-
when
coma
occurs,
it
is
secondary
to cerebral anoxia or intracranial bleed
r.
Death:
- generally occurs at 6-48 hr in untreated severe envenomations (can occur sooner
with IV envenomation)
- 68% in 6-48 hr; 17% < 6 hr; 4% < 1 hr
B. Coral Snake:
- fang marks may be hard to see (range 2-8 mm apart)
- frequent delay in onset of Ssx's (up to 10 hr), followed by extremely rapid progression
- little or no pain at bite site; occasional numbness
- no local necrosis
- earliest evidence may be drowsiness or euphoria
- N/V, increased salivation, paresthesias at bite site
- bulbar paralysis (may occur within 90 min) progressing to peripheral paralysis (curare-like
effects)
- paresthesias, fasciculations
- occasional seizures (especially in children)
- mild hypotension
- death is due to respiratory and cardiovascular failure (can occur 8-12 hr after onset of Ssx's)
VII. FACTORS EFFECTING SEVERITY OF ENVENOMATION:
A.
Age, Size, General Health of Victim
B.
Nature, Location, Depth of Bite
C.
Amount of Venom Injected
D.
Species, Age, Size, Sex, General Health of Snake
E.
Time of the Year, Environmental Conditions
F.
Victim's Sensitivity to the Venom
G.
Pathogens Present in Snake's Mouth
H.
Degree of Activity of Victim After Bite
I.
Type of First Aid Measures and Subsequent Medical Care Rendered
VIII.GRADING SEVERITY OF ENVENOMATION:
- Problems with Grading Scales:
- based largely on local findings and their progression over the first 12 hours - these local findings may be
absent with deep, potentially fatal envenomations
- should never use this type of scale in cases of Mojave rattlesnake or coral snake bites (due to relative lack
of local Ssx's) or in cases of exotic venomous snakebites
- USE GOOD CLINICAL JUDGEMENT - DO NOT OVERLY RELY ON ANY GRADING SCALE!
- SINCE SNAKE VENOM POISONING IS A DYNAMIC PROCESS, THE PATIENT REQUIRES
FREQUENT REASSESSMENT & UPGRADING OF SEVERITY AS APPROPRIATE
