What indicates an abnormal respiratory rate?

An abnormal respiratory rate is typically considered when it falls outside the range of what is deemed normal for an individual at rest. The normal resting respiratory rate for adults generally ranges from about 12 to 20 breaths per minute.

The choice that includes a respiratory rate of 9-18 is significant because it includes a value (9) that is below the lower threshold of the normal range, indicating bradypnea, which means a slower than normal breathing rate. Depending on the context, a rate of 9 could reflect a potential respiratory issue or an underlying medical condition that requires attention.

In contrast, while other choices present rates that fall within generally acceptable parameters (for instance, rates of 11-15 and 14-20 are firmly within the normal range), they do not reflect an abnormal respiratory status. Therefore, the chosen option signifies a potential respiratory abnormality due to the presence of a rate that could indicate inadequate ventilation or other pulmonary concerns.