A patient has a metered-dose inhaler that contains 200 actuations ('puffs'), and it does not have a dose counter.

He is to take two puffs two times a day.

If he does not take any extra doses, identify how many days will this inhaler last at the prescribed dose.

Choice A rationale

A room with air exhaust directly to the outdoor environment is characteristic of a negative pressure isolation room, also known as an Airborne Infection Isolation Room (AIIR). This specialized ventilation system is crucial for containing airborne pathogens like *Mycobacterium tuberculosis*, preventing their circulation to other areas of the hospital and protecting healthcare workers and other clients.

Choice B rationale

Placing a client with active tuberculosis in a room with another nonsurgical client would expose the other client to airborne pathogens, significantly increasing the risk of nosocomial transmission. This violates fundamental infection control principles for airborne diseases and is an unsafe practice, regardless of the other client's surgical status.

Choice C rationale

While the ICU provides a higher level of care, it is not the standard or necessary placement solely for managing active tuberculosis unless the client's clinical condition warrants critical care interventions. The primary consideration for tuberculosis is airborne isolation, not necessarily the intensity of medical support, unless there are severe complications.

Choice D rationale

A room within view of the nurses' station is primarily for close observation of clients requiring frequent monitoring for safety or acute changes in condition. While observation is important, it is secondary to the critical need for airborne infection control for a client with active tuberculosis. Proximity to the nurses' station does not mitigate airborne transmission.

Choice A rationale

Discoloration of tooth enamel is not a primary concern with dry powder inhalers. While some medications can cause oral changes, the main issue with inhaled corticosteroids, often delivered via dry powder inhalers, is localized fungal overgrowth, not direct enamel staining. Good oral hygiene is generally recommended but specifically targets fungal prevention.

Choice B rationale

Halitosis, or bad breath, is not a direct or primary consequence of dry powder inhaler use. While poor oral hygiene can contribute to halitosis, the mechanism for rinsing after inhaler use is to remove residual medication, thereby preventing more significant oral complications like fungal infections.

Choice C rationale

Irritation of oral membranes can occur, but it is not the most significant or common complication that rinsing aims to prevent. Residual powder can cause some local irritation, but the predominant risk with long-term use of inhaled corticosteroids, which are frequently in dry powder inhalers, is opportunistic fungal growth.

Choice D rationale

Rinsing the mouth after using a dry powder inhaler, especially one containing corticosteroids, is crucial to prevent candidiasis. Residual corticosteroid particles in the oral cavity can suppress the local immune response, allowing *Candida albicans*, a yeast normally present in small amounts, to proliferate and cause an oral thrush infection.