This leaves her unable to fully control the pH of the blood under adverse breathing conditions [internal adverse breathing conditions such as suffering from a cold or external adverse breathing conditions such as air with higher than normal levels of carbon dioxide or mould -to which she is very allergic or a combination of both].
The signs and symptoms of hypercapnia with lowered pH are often non specific. A medical history will not tell the doctor what is wrong. Only counting the respiratory rate will unmask hypoventilation and getting a minute ventilation will prove a compensated motor type respiratory failure. To get minute ventilation results one needs to multiply baseline respiratory rate at rest times tidal volume.
Without the results of minute ventilation, there is no hope of getting the correct diagnosis or finding the correct treatment.