Bronchitis effects evidentiary breath testing such that results are erroneously elevated and do not represent the true blood alcohol level. This occurs due to at least two factors,
(1) the temperature elevation associated with an inflammatory response and
(2) the production of alcohol laden secretions that contaminate the breath specimen.

Bronchitis and the resultant inflammation leads to an elevation of local and core body temperature. An elevation of temperature is known to elevate the results on evidentiary breath testing. (Glyn R. Fox, PhD and John S. Hayward, PhD, “Effect of Hyperthermia on Breath Alcohol Analysis,” Journal of Forensic Sciences, JFSCA, Vol. 34, No. 4, July 1989, pp. 836-841.)

Bronchitis is an inflammatory disease of the air passages. It is characterized by inflammation of the air passages, the hallmark of which is increased blood flow to those air passages. This would, of course, provide increased alcohol flow to these air passages.

This would serve as a source of contamination of the breath specimen as it passes through the passages from the alveoli below to the evidentiary breath testing instrument above. This contamination would lead to false elevation of the results of evidentiary breath testing because the instrument received a specimen of alveolar air contaminated with additional alcohol.

The bronchospasm will significantly impair the individual’s ability to produce a breath specimen.

The forced expiration as well as the extended exhalation required to provide a breath specimen could result in an error message “minimum volume not achieved.” Furthermore, the forced expiration would frequently cause paroxysms of coughing.

The bronchospasm can be initiated by two mechanisms, the first mechanism could involve the neurologic innervation of the esophagus as well as the bronchial passages since the neurologic innervation of these two are intimately associated anatomically.

Additionally, and more likely, aspiration of material from the gastrointestinal tract into the respiratory tract would initiate bronchial spasm.
This occurs due to gastroesophageal reflux.

{Breath test}