<prompt> Mechanism of action of sodium nitrite in cyanide poisoningIncreased blood flow to liverProduces methemoglobinemiaIncreased blood flow to kidneyIncreased blood flow to hea  <response>: Cyanide poisoning:- Nitrates generate methaemoglobin which has high affinity for cyanide radical and forms cyanomethaemoglobin. However, this may again dissociate to release cyanide. Therefore, sodium thiosulfate is given to form Sod. thiocyanate which is poorly dissociable and is excreted in urine. Cytochrome and other oxidative enzymes are thus protected from cyanide. Ref:- kd tripathi; pg num:-545 