Envemonations

Crotalid Envenomations Dr. Beuhler

• 2 classes of poisonous snake in NC - pit vipers & coral snakes.  Pit vipers make up the majority of bites we're going to see (Eastern diamondback, Timber rattler, Pygmy rattlesnake, cotton mouth & copperhead)
  

• The venom in the pit vipers is made to digest tissues - has proteolytic and hyaluronisdase activity - this leads to localized extremity dysfunction & systemic effects (emesis, tachycardia, hypotension, flushing, mytoxicity, renal toxicity, allergic reactions, angioedema, coagulopathy, and renal dysfunction)

• Pit viper venom has a degree of neurotoxin activity as well which can lead to weakness, ptosis, and fasiculations as well as localized numbness at bite site

Important steps in management of bite care:

1. First aid: NO ICE; NO TOURNIQUET; Elevation of affected site - don't bend major joints 90 degrees - need to make sure there is good lymphatic flow 
2. Grade bite - this will help determine administration of Crofab, length of observation vs admission 

• Mild - mild swelling, no systemic involvement or lab abnormalities
• Moderate - <50% limb involvement, minimal systemic involvement
• Severe - >50% of limb involvement (crosses major joint), lab abnormalities, systemic effects

3. Decision to treat with Crofab is multifactorial - should be used only in high risk populations or those with moderate to severe envenomations. 

Don't just treat lab abnormalities   

a. Crofab = 10cc/hr; 4 vials & reevaluate after 1-2 hrs. 
Remember crofab interrupts coagulopathy & helps lower compartment pressures & possibly helps with pain - it will NOT stop or reverse local tissue destruction

If you DC home have follow up in < 24 hrs for wound reevaluation