Sinusitis: Causes, Symptoms, and Management

13 Questions

What is the most common cause of acute sinusitis?

Viral infection

What is a common symptom of sinusitis?

Nasal congestion

When is it likely that viral sinusitis has become bacterial?

If symptoms exceed 10 days or worsen

What is a common treatment for sinusitis?

Nasal corticosteroids/decongestants sprays

What is a common complication of sinusitis?

Pharyngitis and cough

How do nerve impulses travel to muscle fibers in the diaphragm?

on phrenic nerves

What happens as the dome-shaped diaphragm moves downward?

The thoracic cavity expands

True or False: Atmospheric pressure forces air into the respiratory tract through the air passages.

True

What fills with air when the lungs fill with air?

lungs

What happens when the diaphragm and external intercostal muscles relax?

Expiration

What causes the collapse of alveolar walls during expiration?

The sudden recoil of elastic tissues in the lungs and thoracic cage

What increases the intraalveolar pressure during expiration?

Tissues recoiling around the lungs

How is air expelled from the lungs?

Air is squeezed out of the lungs

Study Notes

Sinusitis

Inflammation of the membranes lining the sinuses, can be acute or chronic

Aetiology

Acute sinusitis is mostly caused by viral infections, often following a common cold
Bacterial sinusitis often develops after a viral sinusitis
If symptoms persist or worsen after 10 days, viral sinusitis may have become bacterial

Presentation

Symptoms include headache, facial pain, tooth pain, nasal congestion, fever, and postnasal discharge (PND)
May be accompanied by pharyngitis and cough

Management

Treatment options include nasal corticosteroids and decongestants sprays
Analgesics may be prescribed to manage pain
Antibiotics may be used to treat bacterial infections

Inspiration Mechanism

Nerve impulses travel through phrenic nerves to muscle fibres in the diaphragm, causing them to contract
The contraction of the diaphragm causes it to move downward, expanding the thoracic cavity
As the thoracic cavity expands, the intra-alveolar pressure decreases
The decrease in intra-alveolar pressure creates a pressure gradient, allowing atmospheric pressure to push air into the respiratory tract through the air passages
The lungs fill with air as a result of the increased pressure difference

Expiration Process

Diaphragm and external intercostal muscles relax, marking the start of expiration
Elastic tissues of lungs and thoracic cage, stretched during inspiration, suddenly recoil during expiration
Recoil of elastic tissues causes surface tension to collapse alveolar walls
Recoil of tissues around lungs increases intraalveolar pressure
Increased intraalveolar pressure squeezes air out of the lungs