Question

Suppose that a poison causes death because of respiratory failure (the respiratory muscles relax but do not contract). Propose as many as ways as possible that the toxin could cause respiratory failure.

Answer 1

Ans:

Toxic substances can disrupt the respiratory organs and even whole respiratory system after chemicals enter the body by means of inhalation and causing an undue oxidative burden on the lungs. Such mechanism of respiratory failure has many causes and can occur abruptly as acute respiratory failure. Typically, respiratory failure initially affects the ability either to take up oxygen (called oxygenation failure) or to eliminate carbon dioxide (callled ventilatory failure). Eventually, both functions ceases when respiratory failure becomes severe enough.

The respiratory system consists of two parts: (i) the lung, i.e. the gas-exchanging organ, and (ii) the pump, that ventilates the lungs. Failure of the lung caused by variety of diseases (e.g. pneumonia, emphysema and interstitial lung disease) leads to hypoxaemia with hypocapnia called as Hypoxaemic or type I respiratory failure. Failure of the pump (e.g. drug overdosage) results in alveolar hypoventilation and hypercapnia called as Hypercapnic or type II respiratory failure. However, both typesof respiratory failure can coexist in the same patient.