The respiratory system is divided into the upper respiratory tract (URT) and lower
respiratory tract (LRT). The URT consists of organs in the head and neck and is generally
lined with a pseudostratified ciliated columnar epithelium. The LRT consists of respiratory
organs in the thorax and transitions from pseudostratified ciliated columnar epithelium to
simple squamous epithelium.
The respiratory system can also be divided into two main zones: the conducting zone and
the respiratory zone. The conducting zone comprises both the upper and lower respiratory
tracts and primarily functions to provide a pathway for air to travel to and from the lungs.
The respiratory zone consists of the structures where gas exchange occurs, including the
respiratory bronchioles and alveoli.
Patient Background:
David Thompson is a 30-year-old fitness instructor who leads an active lifestyle. David's
days are filled with motivating his clients to achieve their fitness goals, conducting workout
sessions, and promoting healthy living through exercise and nutrition. Despite his hectic
schedule, David maintains a balanced diet, engages in regular exercise routines, and
ensures he gets enough rest to recharge his body. As a non-smoker with occasional alcohol
consumption, David is mindful of his health choices and strives to set a positive example for
his clients.
Recently, David noticed the onset of symptoms that resembled those of a common cold. It
started with a slight tickle in his throat, which gradually progressed to nasal congestion, mild
fatigue, and a persistent cough. As the days passed, David's symptoms intensified as he
even lost his voice, making it difficult for him to carry out his usual fitness routines with the
same energy and enthusiasm.
Feeling concerned about his health and mindful of the potential impact on his clients and
work, David decided to seek medical attention. He scheduled an appointment at the local
clinic to address his symptoms and receive guidance on managing his condition effectively.
Desired Outcomes:
Alleviate David's symptoms, prevent complications such as secondary bacterial infections,
and provide education on preventive measures to reduce the spread of respiratory
infections.
Findings:
David underwent a thorough examination by the healthcare provider. The assessment
revealed clear nasal discharge, mild pharyngeal erythema (redness), and tender cervical
lymph nodes. Despite his symptoms, David's vital signs remain stable, with no evidence of
fever or respiratory distress. Lung auscultation confirms clear breath sounds bilaterally,
without any wheezes or crackles. David’s overall clinical presentation suggests a viral upper
respiratory tract infection, likely exacerbated by close contact with an affected individual at
the gym.
Questions:
1. Identify the structures of the upper and lower respiratory tracts.
Upper Respiratory Tract (URT):
• Nasal cavity: The nasal cavity is lined with a pseudostratified ciliated
columnar epithelium and is responsible for filtering, warming, and
humidifying the air we breathe.
• Pharynx: The pharynx is divided into three regions: nasopharynx,
oropharynx, and laryngopharynx. It serves as a passageway for both
air and food.
• Larynx: The larynx, also known as the voice box, is involved in phonation
and protects the lower respiratory tract by preventing food from entering
the trachea.
Lower Respiratory Tract (LRT):
, • Trachea: The trachea, or windpipe, is a tube that connects the
larynx to the bronchi. It is lined with pseudostratified ciliated
columnar epithelium and reinforced with cartilage rings to maintain
its shape.
• Bronchi: The bronchi are the main passageways that branch off
from the trachea and lead into the lungs. They further divide into
smaller bronchioles.