Cessation of breathing

Sleep apnea The temporary cessation of breathing during sleep can be caused by airway narrowing as a result of soft tissue swelling. 

Apnea is repetitive episodes of cessation of breathing during sleep. The goals of therapy are to alleviate sleep disordered breathing (Fig. 72-1). 

Physiological action Cessation of breathing—death may follow Required level of protection Protective mask and clothing... 

Potassium cyanide is a dangerously toxic substance. Ingestion of 100 to 150 mg can cause collapse and cessation of breathing in humans. At lower doses, the acute effects are nausea, vomiting, headache, confusion and muscle weakness (Patnaik, P. 1999. A Comprehensive Guide to the Hazardous Properties of Chemical Substances, ed. pp. 292-294. New York John Wdey Sons). Contact with acid can liberate highly toxic vapors of hydrogen cyanide. Sodium thiosulfate and sodium sulfate have shown antidotal activity to KCN toxicity. 

Respiratory system respiratory depression hypothermia bradycardia with increases or decreases in blood pressure apnea (cessation of breathing that is usually temporary). 

Gas at high concentration results in immediate unconsciousness, and then cessation of breathing. At lower concentrations, gas irritates the respiratory system and eyes and causes headache, dizziness, and weakness. Avoid inhaling gas.23 TLV-TWA 10 ppm (14 mg/m3) TLV-STEL 15 ppm (21 mg/m3).23... 

Symptoms of Poisoning Shakiness, blurred vision, tightness in the chest, confusion, changes in heart rate, convulsions, coma, cessation of breathing and paralysis . 

Another arrow poison, common in South America, was curare, which was extracted from a plant (Chondrodendron). A constituent of this extract, tubocurarine, blocks transmission of nerve impulses to muscles, leading to complete paralysis and death from cessation of breathing. The chemical has been used as a drug for the purpose of relaxing the muscles of a patient. One of the arrow poisons used in Africa was extracted from a species of the plant Strophanthus and contained strophanthidin and oubain (pronounced waabain ). These have similar effects as digitalis on the heart and, in sufficient quantities, can be lethal. The poisoned patient would suffer from erratic rhythms of the heart, a slowing of the heart, and possibly uncontrolled movements of the heart muscle (ventricular fibrillation). 

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