NCEMI eTools

Crotalid snakebite severity score

A research tool for scoring the severity of crotalid snake bites in adults. It correlated well with physician assessment of severity.

Pulmonary system

	No symptoms/signs 0 points
	Dyspnea, minimal chest tightness or discomfort, or respiratory rate 20-25 1 points
	Moderate respiratory distress (tachypnea, 26-40 breaths/minute, accessory muscle use 2 points
	Cyanosis, air hunger, extreme tachypnea, or respiratory failure 3 points

Cardiovascular system

Local wound

	No symptoms/signs 0 points
	Pain, swelling, or ecchymosis within 5-7.5 cm of bite 1 points
	Pain, swelling, or ecchymosis involving less than half the extremity (7.5-50 cm from bite site) 2 points
	Pain, swelling, or ecchymosis involving half to all of extremity (50-100 cm from bite site) 3 points
	Pain, swelling, or ecchymosis extending beyond affected extremity (over 100 cm from bite site) 4 points

Gastrointestinal symptoms

	No symptoms/signs 0 points
	Pain, tenesmus, or nausea 1 points
	Vomiting or diarrhea 2 points
	Repeated vomiting, diarrhea, hematemesis, or hematochezia 3 points

Hematologic system

	No abnormalities 0 points
	Slightly abnormal (PT under 20s; PTT under 50s; Platelets 100K-150K; or fibrinogen 100-150 mcg/mL) 1 points
	Abnormal (PT 20-50s, PTT 50-75s, platelets 50K-100K, or fibrinogen 50-100 mcg/mL 2 points
	Very abnormal (PT 50-100s, PTT 75-100s, platelets 20K-50K, or fibrinogen under 50 mcg/mL) 3 points
	Markedly abnormal, with serious bleeding or its threat. Unmeasurable PT or PTT, or platelets under 20K, or undetectable fibrinogen, or other severe lab abnormalities 4 points

Central nervous system

	No symptoms/signs 0 points
	Minimal apprehension, headache, weakness, dizziness, chills or paresthesia 1 points
	Moderate apprehension, headache, weakness, dizziness, chills, paresthesia, confusion, or fasciculation at bite 2 points
	Severe confusion, lethargy, seizures, coma, psychosis or generalized fasciculation 3 points