How does complications in whooping cough such as pneumonia ear infection seizures and dehydration develop?

how and why these complications such as pneumonia.seizures.ear infection and dehydrationresult in pertussis or whooping cough

They don't......whooping cough/pertussis is a completely different infection that creates a membrane in the throat that causes a whooping kinda cough. In saying this, it is not unusual for someone who is sick with something else to get sick with whooping cough, or vice versa. The body is vulnerable to infections as it tries to fight off the primary infection. We do tests for whooping cough when we test for RSV simply because we have seen babies sick with both. RSV is a virus and whooping cough is a bacterial infection. If a person has whooping cough and NO other infection, their lung fields are most often clear via xray. Dehydration can result from someone, especially a baby, not being able to take in sufficent liquid because of the cough, the difficulty breathing from the cough, or pneumonia...or from pain during the sucking process cause of the ear infection. High temps may be the cause of seizure activity....or low oxygen levels to the brain. It is difficult to give a diffinitive answer because your info is limited. How old is this patient with whooping cough? Has this patient had pertussis vaccination? Is this patient teething also? Aspiration pneumonia is a high risk because of the person's inability to handle secreations especially if it is a baby....More info please.