Respiratory System, Hypoxia, Secretion Clearance, and Airway Management

Flashcards covering upper and lower airway structures, gas transport, age-related respiratory changes, hypoxemia vs. hypoxia, secretion clearance, choking interventions, oxygen therapy devices, and artificial airways.

What structures comprise the upper and lower respiratory airways?

The upper airway consists of the nose, mouth, pharynx, larynx, and trachea. The lower airway consists of the bronchi, bronchioles, and alveoli.

How many lobes do the right and left lungs contain, and what volume of air is exchanged per normal breath?

The right lung has $3$ lobes and the left lung has $2$ lobes. A normal breath exchanges $500\,\text{mL}$ of air.

How are oxygen and carbon dioxide transported in the blood, and how does the central nervous system (CNS) regulate breathing?

Oxygen ($O_2$) is transported via hemoglobin in red blood cells (RBCs), while carbon dioxide ($CO_2$) is carried mostly in plasma. Chemoreceptors in the aorta and carotids detect $O_2$ and $CO_2$ changes, and the medulla adjusts breathing rate based on pH, $CO_2$, and $O_2$ levels.

What respiratory changes occur in adults after age $70$?

Age-related changes include decreased elasticity of the thoracic cage and lung tissue, drier airways with thicker mucus, less effective cilia function, decreased elastic recoil requiring respiratory muscles for expiration, increased alveolar thickness causing slower gas exchange, decreased oxygen saturation ($PaO_2$ drops to $75\text{--}80\,\text{mm Hg}$), and decreased respiratory reserve.

What is the clinical distinction between hypoxemia, hypoxia, and anoxia?

Hypoxemia is low oxygen in the bloodstream, hypoxia is reduced or inadequate oxygen in body tissues/cells, and anoxia is a complete lack of oxygen.

How is the delivery truck analogy used to differentiate hypoxemia and hypoxia?

A delivery truck that is half full represents hypoxemia (low $O_2$ in blood), whereas oxygen packages never making it to the house represents hypoxia (low $O_2$ in tissues).

What are the early, initial, later, and late signs/symptoms of hypoxia?

Early: restlessness, memory lapse, sitting up to breathe. Initially: increased blood pressure, increased pulse, and increased respiratory rate. Later: decreased blood pressure, decreased pulse, arrhythmia, and use of accessory muscles. Late: cyanosis, muscle retractions, and stridor.

What is the universal sign of choking, and how should airway obstructions be managed in adults versus infants?

The universal sign of choking is hands clutching the throat. Perform abdominal thrusts for adults and children older than $1$ year. Perform back slaps and chest thrusts for infants younger than $1$ year.

What are the rules for Hands-Only CPR performed by untrained bystanders?

Untrained bystanders should perform $30$ chest compressions without rescue breaths, pushing hard and fast on the center of the chest.

What guidelines should be followed for performing postural drainage?

Postural drainage mobilizes secretions using gravity. It should be performed $45\text{--}60\,\text{min}$ before meals (or in the morning before meals) $2\text{--}4$ times a day. Position the patient for $5\text{--}15\,\text{min}$ and auscultate lung sounds before and after.

What are the oxygen concentration percentages for standard oxygen delivery devices?

Nasal Cannula: $24\text{--}44\%$. Simple Face Mask: $36\text{--}50\%$ (or $24\text{--}58\%$ at $3\text{--}7\,\text{L/min}$). Partial Rebreather: $40\text{--}60\%$. Non-rebreather: $60\text{--}90\%$ (highest concentration). Venturi Mask: $24\text{--}50\%$ (precise delivery).

What are the main characteristics and benefits of a Transtracheal Catheter?

It delivers a variable percentage of $O_2$, remains hidden, is efficient, and causes less nasal irritation.

What are the functions and safety rules for pharyngeal (naso/oro) artificial airways?

They are used post-operatively to prevent tongue obstruction in spontaneously breathing patients and must never be left unattended.

What are the characteristics and clinical risks of an Endotracheal Tube (ETT)?

An ETT is inserted for unconscious or non-breathing patients for short-term use ($48\text{--}72\,\text{hrs}$ or longer). It blocks speech (requiring communication aids) and poses a risk of mucosal ulcers with prolonged use.

What are the causes of hypoxia and hypoxemia?

Causes include respiratory diseases, high altitude, pulmonary edema, anemia, inadequate ventilation, and impaired circulation.

What techniques can be used for clearing secretions in patients?

Techniques include coughing exercises, postural drainage, and the use of nebulizers or chest physiotherapy.

What is the best time to collect a sputum specimen?

The best time to collect a sputum specimen is in the morning, as secretions tend to accumulate overnight.

Why should a patient on oxygen avoid smoking and wear 100% cotton clothing?

Patients on oxygen should avoid smoking due to the increased fire risk from oxygen, and 100% cotton clothing is recommended as it reduces static electricity and potential ignition sources.