Biology Reference
In-Depth Information
selectively bred by commercial breeders and “herpetoculturists.”
Heterodon nasicus
have
rarely caused medically significant bites (see Plate 4.24D-J) and are phlegmatic captives.
Almost all of the seven documented cases occurred when offering a captive specimen food, or
shortly after contacting food items before handling the snake (see text and
Table 4.1
).
(D-F) Western hognose snake (
H. nasicus
), breeder-selected pattern variants.
These
phases are variously called “anaconda” (in reference to the numerous spots reminiscent of
the green anaconda,
Eunectes murinus
, a boiid member of the Henophidia), striped, reduced
pattern, hypomelanistic, etc. The physician must remain aware of such variants if presented
with a snake deemed responsible for a bite, and the specimen is identified as a familiar
species, yet has an unfamiliar appearance. This is particularly relevant in the case of a
presenting victim who has a private snake collection.
Plate 4.91
A, photo copyright to Trevor
D. Keyler;
Plate 4.91B-F
, photos copyright to Brent W. Bumgardner.
indicated, establishment of a management plan including appropriate tests and investiga-
tions. The understandable anxiety associated with snakebite regularly creates a group of
signs and symptoms that can mislead both patients and their physicians. These include
tachycardia, palpitations, sweating, overbreathing/hyperventilation (causing acropares-
thesia, tetany, lightheadedness, faintness, and syncope) and, in extreme cases, histrionic
conversion disorders. These features are often misinterpreted as signs of envenomation
and are described naïvely and uncritically in accounts of snakebites written by the vic-
tims themselves or by authors without medical training. Autonomic responses to even a
medically insignificant bite can exacerbate some comorbidities, such as ischemic heart
disease (angina) or generalized anxiety disorder (panic). Thus, attendance and review by
a physician is strongly recommended in any case reportedly featuring medically signifi-
cant effects. It is disconcerting that fewer than 35% of published cases (not including ret-
rospective reviews) feature medically qualified evaluation of the victim.
Conclusions and Recommendations
Anyone bitten by a snake of known or unknown medical importance that develops
signs/symptoms and/or is concerned regarding possible effects of the bite should be
promptly reviewed by a medical professional. As many non-front-fanged colubroid
species are likely to be unfamiliar to most medical personnel, consultation with a
clinical toxinologist is desirable if not mandatory, as with any case of unusual intoxi-
cation/poisoning. Even medically insignificant bites may exacerbate some preexist-
ing comorbidities, and patients so affected should be managed appropriately.
4.5.1.3 Frequent Authorship (“Auto-Reporting”) of Snakebite
Cases by Victims
Another profoundly serious flaw in many of these reports is authorship by the vic-
tims themselves. Not only is this unacceptably subjective, but it reinforces the grave
drawback posed by a lack of clinical acumen/training of these authors. Even a clini-
cally trained victim/author should not function as the senior contributor to their own
snakebite case report.
Lack of medically qualified review often amplifies clinically insignificant signs/
symptoms that are uncritically reported (see
Table 4.1
and Section 4.5.1.4 for
