TOX 11 - Cyanide

Question 1

Source

Answer 1

CN releasing compounds like HCN gas

Question 2

Absorption

Answer 2

All routes except skin

Question 3

Mechanism

Answer 3

CN- binds to Fe+++ containing enzymes (cytochrome) -> blocks tissue oxidative process -> cytotoxic hypoxia

Question 4

Symptoms

Answer 4

Anoxia of CNS and heart -> coma, respiratory arrest

Question 5

Treatment

Answer 5

1. NaNO2 administration: makes methaemoglobin that has iron with higher CN- affinity, thus restoring cytochrome enzymes
2. Na2S2O3 administration: detoxify cyanomethaemoglobin