Oxygenation and Upper Airway Disorders

50 practice flashcards covering Ventilation, Capnography, Respiratory Acidosis, and Upper Airway Disorders based on the Nursing lecture notes.

What is ventilation, and what two processes make up its physical act?

Ventilation is the physical act of breathing, consisting of inhalation (moving air into the lungs) and exhalation (moving air out of the lungs).

What is the primary function of the alveoli, and what waste product do they help remove?

The alveoli are the site where gas exchange occurs, and they help remove carbon dioxide ($\text{CO}_2$), which is a metabolic waste product from the body.

How does emphysema affect alveolar structure and breathing?

Emphysema breaks down the walls of the alveoli, making it difficult to breathe out.

How does pneumonia pathologically affect the alveoli?

Pneumonia fills the air sacs (alveoli) with fluid or pus.

Which muscles drive ventilation by creating pressure changes in the chest cavity?

The diaphragm and intercostal muscles.

What is lung compliance, and how is it calculated?

Lung compliance is the ability of the lungs and thorax to expand. It is measured as the change in lung volume divided by the change in pressure.

What is the normal value for respiratory system compliance?

$$100\,ml/cm\,H_2O$$

What clinical condition is cited as an example of stiff lungs (low compliance), and how does it affect breathing?

Pulmonary edema; it makes inhalation hard work.

What clinical condition is associated with floppy lungs (high compliance), and how does it affect breathing?

Emphysema/COPD; the lungs inflate easily but fail to push air back out properly.

What three factors directly affect lung compliance?

Surfactants (which lower surface tension), tissue structure (which resists stretching and snapping back), and lung volume.

What is airway resistance, and how is it calculated?

Airway resistance is the opposition to airflow caused by friction in the respiratory tract. It equals the pressure difference between the mouth and alveoli divided by the airflow rate.

Which factor has the largest impact on airway resistance?

Airway diameter, because smaller radii exponentially increase resistance.

What are short-acting bronchodilators used for, and what two examples are given in the notes?

They act as rescue inhalers that work fast to stop sudden breathing trouble with effects lasting a few hours. Examples include Albuterol (Ventolin) and Ipratropium (Atrovent).

What are long-acting bronchodilators used for, and what two examples are given in the notes?

They are controller medications taken on a regular schedule that take longer to start working but keep airways open all day and night. Examples include Salmeterol (Serevent) and Formoterol (Perforomist).

What combination inhaler is mentioned in the text, and what active medications does it contain?

Combivent, which mixes Albuterol and Ipratropium.

What is tidal volume?

The amount of air that moves in or out of the lungs with each normal breath.

What are the normal adult tidal volume values for males and females?

Male: about $500\,ml$ per breath; female: about $400\,ml$ per breath.

What body weight formula is used to estimate normal tidal volume?

$6\,ml$ to $8\,ml$ per $\text{kg}$ of ideal body weight.

What is capnography ($\text{EtCO}_2$)?

Continuous, non-invasive measurement (numeric value) and visual waveform display of $\text{CO}_2$ in exhaled breath.

How do capnography devices detect the amount of $\text{CO}_2$ present in a gas sample?

Devices use infrared light absorption to detect how much $\text{CO}_2$ is present in the gas sample.

How do mainstream and sidestream capnography sampling methods differ?

Mainstream attaches a sensor directly to the breathing tube, whereas sidestream continuously pulls a gas sample through tubing into a separate monitor.

How does capnography assist during cardiopulmonary resuscitation (CPR)?

It monitors the quality of chest compressions and helps detect a return of spontaneous circulation (ROSC).

In capnography monitoring, which condition is represented by the slanted rising phase waveform labeled 'Lower airway obstruction'?

Asthma or COPD.

What three major factors influence ventilation?

Lung mechanism, airway resistance, and respiratory drive.

What is hypercapnia, and what commonly causes it?

An abnormally high level of $\text{CO}_2$ in the blood, typically caused by hypoventilation (breathing too slowly or shallowly) or poor gas exchange in the lungs.

What is respiratory acidosis, and what threshold of blood pH defines it?

A condition where blood pH drops below $7.35$ because the lungs cannot remove enough $\text{CO}_2$, causing $\text{CO}_2$ to build up in the body.

What are potential causes of acute respiratory acidosis?

Severe asthma attacks, blocked airways, overdose of opioids, sedatives, or alcohol that slow brain activity, and sudden lung or chest injury.

What medical conditions can lead to chronic respiratory acidosis?

COPD or emphysema, severe obesity restricting chest expansion, or neuromuscular disorders like muscular dystrophy or ALS (amyotrophic lateral sclerosis / Lou Gehrig disease).

What diagnostic test measures blood pH, $\text{O}_2$, and $\text{CO}_2$ levels in respiratory acidosis?

Arterial Blood Gas (ABG).

What common signs and symptoms indicate respiratory acidosis?

Trouble breathing or shortness of breath (SOB), extreme tiredness, sleepiness, lethargy, confusion or fuzzy thinking, headaches (especially upon waking), and tremors or muscle twitching.

What anatomical structures constitute the upper airway?

The nose, nasal passages, paranasal sinuses (pairs of maxillaries, frontal, ethmoid, sphenoid), pharynx, and portion of the larynx above the vocal folds.

What are the main physiological functions of the upper airway?

Filtering, warming, and humidifying inspired air before it reaches the lungs, blocking harmful germs/irritants, and contributing to speech and olfaction.

Name the four pairs of paranasal sinuses included in the upper airway.

Maxillaries, frontal, ethmoid, and sphenoid.

What is viral rhinitis?

A highly contagious upper respiratory infection commonly known as the common cold, causing swelling and inflammation in the lining of nasal passages.

What percentage of colds are caused by rhinoviruses, and how many distinct virus types exist in this family?

Rhinoviruses cause up to $40\%$ of colds and have at least $100$ distinct virus types in their group.

Besides rhinoviruses, what three other virus families cause the common cold?

Coronavirus, adenovirus, and respiratory syncytial virus (RSV).

Why has the development of a vaccine for the common cold not been possible?

Because so many different viruses can cause cold symptoms.

What three types of rhinitis are listed in the lecture outline?

Allergic, non-allergic, and infectious.

To what specific receptor do rhinoviruses attach on epithelial cells?

Intercellular adhesion molecule-1 (ICAM-1) receptors.

What occurs after a rhinovirus attaches to the ICAM-1 receptor on an epithelial cell?

The virus enters, takes over cell metabolism, replicates, and causes host cell death.

What chemical signals are released by infected epithelial cells during viral rhinitis, and what is their role?

Cytokines and chemokines are released to recruit immune cells.

What mechanism leads to tissue swelling and nasal congestion during viral rhinitis?

Blood vessels in the nose widen and become leaky.

What causes rhinorrhea (runny nose) during viral rhinitis?

Nerve pathways stimulate mucus glands to overproduce fluid.

What is the typical timeframe for symptom onset and peak during viral rhinitis?

Symptoms typically appear $1$ to $3$ days after exposure and peak between the $2\text{nd}$, $3\text{rd}$, and $4\text{th}$ days.

When is a patient infected with viral rhinitis most contagious?

During the first $24$ hours of the illness, remaining infectious for as long as symptoms last.

What symptoms mark the early stage of viral rhinitis, and how quickly can they appear?

Scratchy or sore throat, which can appear as early as $10$ hours after infection.

What symptoms characterize the acute stage of viral rhinitis?

Frequent sneezing, heavy watery or clear runny nose, and severe nasal and sinus congestion.

What symptoms characterize the late stage of viral rhinitis?

Low-grade fever, mild headache, hoarseness, post-nasal drip, and a nagging cough.

What instruction is given regarding the use of OTC nasal spray decongestants like Oxymetazoline?

Do not use for more than $3$ consecutive days to avoid severe rebound congestion.

How do sleep and exercise contribute to preventing viral rhinitis?

Getting at least $7$ hours of sleep per night and exercising regularly help prevent colds and promote overall immune health.