Snake Bites

Question 1

What are some examples of venomous snakes that can be found in the US? What is their scientific name? What are they also referred to (due to their anatomy)?

Answer 1

Rattlesnakes, water moccasins (cottonmouths), and copperheads
Family: Viperidae, subfamily: Crotalinae
AKA “Pit vipers”, from their heat sensing pit located behind the nostrils

Question 2

Where are rattlesnakes found?

Answer 2

Native to and live in all states except for Alaska, Hawaii, and Maine

Question 3

Where are water moccasins or cottonmouths found?

Answer 3

Southeast-South, Virginia-Texas

Question 4

Where are copperheads found?

Answer 4

Eastern continental states, Massachusetts-Texas

Question 5

A majority of snake bites occur in (children/adults) (males/females)

Answer 5

Adult men

Question 6

~____% of envenomated patients are hospitalized

Answer 6

50%

Question 7

Ecchymosis and progressive swelling are signs of _________

Answer 7

Local tissue damage

Question 8

______ reactions, such as nausea, vomiting, abdominal pain, paresthesias, and dizziness, suggest (less/more) severe envenomation

Answer 8

Systemic; more

Question 9

What are systemic signs from increased vascular permeability following a snake bite?

Answer 9

Tachycardia, tachypnea, and hypotension

Question 10

Oral paresthesia, unusual taste, fasciculations, altered mental status, seizures are all signs of ______

Answer 10

Neurotoxicity

Question 11

_________ is the only type of Crotalid bites that can cause neuromuscular weakness with respiratory failure. This reaction can be delated up to ____ hours post-bite.

Answer 11

Mojave rattlesnake; 12

Question 12

Before the patient arrives at the hospital following a snake bite, the patient should immobilize the injured body part at what level?

Answer 12

Heart level

Question 13

Snake bite patients (should or should not) use pressure immobilization, tourniquets, incision and oral suction, or mechanical suction devices

Answer 13

should not

Question 14

T/F If a snake is dead, it can still bite you

Answer 14

True, there may still be an intact bite reflex

Question 15

T/F Every time a snake bites, there is venom delivered

Answer 15

False, dry bites comprise 25% of all Crotalinae snake bites

Question 16

T/F Hypotension/altered mental status following a snake bite are rare

Answer 16

True

Question 17

Why do we order a serum creatine kinase and UA following a snake bite? What are we looking for?

Answer 17

Rhabdomyolysis

Question 18

T/F You should elevate a snake bite wound

Answer 18

False, keep at level of the heart

Question 19

Matching: Mild, Moderate, Severe envenomation
A. Edema >12 inches around wound, altered lab values
B. Local pain and edema, normal lab values
C. Petechiae, hypoTN, ecchymosis, abnormal lab values

Answer 19

A. Edema >12 inches around wound, altered lab values –> Moderate
B. Local pain and edema, normal lab values –> Mild
C. Petechiae, hypoTN, ecchymosis, abnormal lab values –> Severe

Question 20

Is CroFab dosing weight based?

Answer 20

No

Question 21

If a pt has certain allergies, they should not receive CroFab. What allergies are we particularly concerned about?

Answer 21

Dust mites, papaya, pineapple, and latex

Question 22

CroFab should be administered at a (fast/slow) rate

Answer 22

Slow

Question 23

T/F Tetanus prophylaxis is recommended for all snake bite patients

Answer 23

True

Question 24

CroFab shows a decreased time for return to full function, but overall no significant difference in outcomes ___ months out from injury.

Answer 24

4

Question 25

Can CroFab be administered to individuals with known allergy to it?

Answer 25

Yes, in serious envenomation cases

Question 26

T/F CroFab is safe for use in pregnant women and young children

Answer 26

False, due to stabilizing preservatives

Question 27

Acute reactions to CroFab are often (immunologic/nonimmunologic) in nature, however allergic reactions can be secondary to _____ _____, particularly in those who have been bitten before or who handle snakes

Answer 27

nonimmunologic; venom sensitivity

Question 28

1st line tx for anaphylaxis is _____. 2nd line?

Answer 28

1st line: Epinephrine | 2nd line: H1 Antihistamine, Beta 2 adrenergic agonists, and glucocorticoids

Question 29

Why is antivenom administration, and not FFP or heparin, the primary tx for Crotalinae-induced coagulopathy?

Answer 29

Because transfused platelets and coagulation factors in FFP are inactivated by Crotalinae venom Heparin is also ineffective as the thrombin-like substances in the venom are not inhibited by antithrombin III

Question 30

Snake venom contains a Protein C activator and thrombin-like glycoproteins which form _____ by working like _____ on the fibrinogen molecules. This results in the development of decreased ______, prolonged _____, and decreased _____

Answer 30

fibrin; thrombin; fibrinogen, PT/PTT, platelets

Question 31

What is the triad of rhabdo presentation? hint: think urine content/color/and lab value)

Answer 31

pigmented granular casts in the urine, | a red to brown color (“iced tea”) of the urine, and a very high total creatine kinase (CK)

Question 32

What is the initial recommended tx of rhabdo? What electrolyte imbalances should be checked for as well?

Answer 32

IV hydration NS | HYPERkalemia, HYPERphosphatemia, HYPOcalcemia

Question 33

What is a potential complication of rhabdo?

Answer 33

Acute renal failure

Question 34

_____ syndrome is a rare but serious complication of a snake bite, with paralysis being a (early/late) finding.

Answer 34

Compartment syndrome; late

Question 35

What is currently accepted as the best prevention/treatment of compartment syndrome?

Answer 35

CroFab

Question 36

T/F Pts with compartment syndrome should be immediately taken in for surgery

Answer 36

False, surgical intervention should be avoided if at all possible

Question 37

A fasciotomy should only be considered when the difference between compartment pressure and diastolic blood pressure is less than ____ mm Hg or when clinical symptoms are obvious

Answer 37

30 mmHg

Question 38

A _____ monitor can be used to evaluate a pt's compartment pressure, however, if one is not available, what can be used in its place?

Answer 38

Stryker; an 18-gauge needle can be attached to an arterial pressure monitor

Question 39

If a pt has received anti-venom tx, do they require admission?

Answer 39

Yes

Question 40

If a pt has mild or no toxicity on initial clinical assessment and normal baseline testing, how long should they be observed for following snake bite?

Answer 40

8-12 hours

Question 41

If a pt is a child or elderly, has significant comorbidities, or has poor social supports for follow-up, how long should they be observed for following snake bite?

Answer 41

up to 24 hours

Question 42

Since neurotoxicity may be delayed in asymptomatic patients with suspected Mojave rattlesnake bites, how long should they be observed for following snake bite?

Answer 42

12-24 hours

Question 43

T/F Most victims of venomous North American snakes do not fully recover

Answer 43

F, they do; death following Crotalinae snake bites is rare

Question 44

Morbidity/mortality usually associated w/ bites to the ____ or _____

Answer 44

face, UEs

Question 45

What is the most common loss following a snake bite, in terms of ability?

Answer 45

Loss of ROM