Respiratory System Notes 20 Respiratory... · Respiratory System Notes 2 ... The cartilage part of the rings keeps our trachea open during breathing, despite ... bunch of grapes

Respiratory System Notes

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2.3 cont'd ‐ Respiratory System

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Nose, Pharynx, Larynx, TracheaAir needs to get from the outside environment into our lungs where we can absorb the oxygen.

The Nose ‐ What are the primary roles of the nose (including the nasal cavity)?

1) Nasal cavity warms up the air as it flows past, because it is filled with thin blood vessels.

2) Mucus produced in the nasal cavity moistens the air and traps incoming bacteria and other foreign debris. Enzymes in the mucus help destroy bacteria.

3) Cilia in the nasal cavity help brush the mucus down our throat into our stomach

4) The sinuses ‐ lighten the skull and produce mucus

Pharynx ‐ What happens at each of the three regions of the Pharynx?

1) Nasopharynx ‐ air passes the pharyngeal tonsil (adenoid). This also where our ear tubes (pharyngotympanic tubes) are located. These tubes drain our middle ear.

2) Oropharynx ‐ home of the palatine tonsils and the place where air and food will meet

3) Laryngopharynx ‐ home of the lingual tonsils. Air goes through the trachea, while food go through the esophagus.


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Trachea ‐ What is the common name for the Trachea?

The Windpipe

What is the purpose of the "C‐Shaped" cartilage rings surrounding the Trachea?

1) The open part of the rings sit against the esophagus and allow the esophagus to expand when we swallow a large piece of food.

2) The cartilage part of the rings keeps our trachea open during breathing, despite the changes in pressure that occur.

Larynx ‐ What is the common name for the Larynx?

The voice box. It also makes sure that air and food go to the correct places.

How does it work to produce sounds?

Passes air through two folds called vocal chords. This causes the chords to vibrate at the correct frequency to make speech.

Our Trachea is lined with mucus, but we don't want a great deal of extra mucus in our lungs.

What keeps mucus out of our lungs?Tiny hair‐like projections called cilia beat in the opposite direction of air and bring mucus (with dust and other debris) back up our trachea where we can either swallow or spit out the mucus.

Why do smokers have the "smoker's cough"?Cilia in the trachea become destroyed, which means that the only way to keep mucus out of the lungs is to cough it up.


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Nasal Cavity

Pharynx

Larynx

Trachea

Upper Respiratory Tract:(Main Structures/Purpose)


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Lower Respiratory Tract

Once the air has passed through the Upper Respiratory Tract, it moves on to the Lower Respiratory Tract where gas exchange occurs.

Conducting Zone ‐ how air moves from the trachea to the alveoli

Primary Bronchi ‐ all bronchi are lined with cartilage to help them stay open.Two sides with slight differences in each. The right side is wider, shorter and straighter than the left. The right side is far more likely to be the site of infection or an inhaled foreign object to become lodged.

Secondary and Tertiary Bronchi ‐ smaller subdivisions of the bronchi that will eventually lead to bronchioles

Bronchioles ‐ all but the smallest bronchioles have cartilage in themTerminal Bronchioles are the smallest part of the conducting zone and lead into the respiratory zone where they become respiratory bronchioles

Respiratory Zone ‐ where gas exchange occurs

Alveoli ‐ hollow structures that are the site for gas exchange. Resemble a bunch of grapes. Our lungs have millions of alveoli which means most of our lungs are actually empty space.

Conducting Zone

Respiratory Zone

Alveoli


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Gas Exchange Process in Alveoli:

The process occurs in the lungs and is the result of diffusion

Diffusion ‐ the movement of a substance from high concentration to low concentration

When we inhale, the alveoli have a high concentration of O2 and a low concentration of CO2.

Recall that the blood coming from the heart to the lungs has a low concentration of O2 and a high concentration of CO2.

Therefore:

O2 will diffuse from the alveoli to the capillaries where it makes its way back to the heart.

CO2 will diffuse from the capillaries to the alveoli, where it is exhaled.

Alveolus


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What are the mechanics of breathing?

It's all about muscles, the ribcage, and pressure

During Exhalation:

1) Muscles ‐ (Passive Exhalation) Diaphragm and External Intercostals relax. ‐ (Active Exhalation) Internal Intercostals contract to help depress the ribcage. Abdominal muscles also contract to force the internal organs upward against the diaphragm.

2) Ribcage ‐ (Passive Exhalation) returns to it's resting size‐ (Active Exhalation) depresses to slightly smaller than it's resting size because of the internal organs forcing upwards

3) Relative pressure ‐ the pressure inside the ribcage is higher than the atmospheric pressure, so air rushes out until the pressures are equal

During Inhalation:

1) Muscles ‐ Diaphragm and External Intercostals (rib muscles) contract, which expands the thoracic cavity.Diaphragm moves down which increases the height of the thoracic cavity.

2) Ribcage ‐ lifts and moves forward. Lungs are attached to the ribcage (sort of) so they expand when the ribcage expands.

3) Relative pressure ‐ the pressure inside the ribcage now lower than the atmospheric pressure outside the body, so the air rushes in to fill up the space until the pressures are equal.

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**Keep this in mind: Volume changes lead to pressure changes, which lead to the flow of gases to equalize the pressure**


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What controls our breathing rate?

1) Brain and Nerve Signals‐ Signals between the brain and nerves in the diaphragm set the breathing rate at about 12‐15 breaths/minute when resting.‐During exercise the nerve signals usually increase the rate‐Occasionally, the rate might not increase during exercise, but the intensity of the breath might change (deeper breaths in/force breaths out)

2) Physical Factors ‐ talking, coughing, exercising, increased temperature

3) Volition (conscious control)‐Obviously we can control our breathing if we want to‐But the respiratory centers in our body will ignore our wishes if we are running too low on oxygen or if our blood pH is too low

4) Emotional Factors‐Fear, surprise, anger, etc. can all change our breathing rate.‐This is our brain's response to help get us ready to react to a stressful situation if we need to

5) Chemical Factors‐If blood pH changes, our breathing rate will change to help regulate it

O2 sensor

CO2 sensors in brain


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Extra Information:

Alveolar Macrophages ‐ alveoli are the last line of defense for the respiratory system. In our lungs we have cells called macrophages (phage ‐ to eat, macro ‐ large particles). Their job is to pick up bacteria, carbon particles, dust, and other debris that might have found its way to the alveoli.

Surfactant ‐ a fat molecule that coats the wall of the alveoli. Without surfactant, our alveoli would collapse after each breath.

**Produces Surfactant**

**healthy surfactant**

**unhealthy surfactant**


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Lower Respiratory Tract:


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Common Diseases/Illnesses of the Respiratory System(in Alphabetical Order)

Asthma ‐ breathing disorder usually caused by a sensitivty to dust, pollen, animals, medications, or possibly food. Stress, overexertion, and/or infection can also cause an asthma attack. An asthma attack consists of bronchospasms (narrowed bronchioles), mucus production, and swelling in the lungs. All of this makes it difficult to breathe. Symptoms include wheezing, coughing (with mucus), and tightness in the chest. Treatments include bronchodilators (inhalers) to open of the bronchioles, epinephrine, oxygen therapy, and anti‐inflammatory medications. Knowing what triggers your asthma attack is crucial in preventing them in the future.

Bronchitis (Acute) ‐ inflammation of the bronchi. Caused by an infection (bacteria or virus). Symptoms are a productive (mucus) cough, difficulty breathing, bubbly breath sounds, chest pain, and fever. Treatments include antibiotic (if bacterial), expectorants (to get rid of mucus), rest, and plenty of water.

Bronchitis (Chronic) ‐ repeated bouts of acute bronchitis can lead to chronic bronchitis, especially in those who smoke. Characteristics include chronic inflammation, damaged cilia, and enlarged mucus glands. Symptoms are excessive mucus, wheezing, difficulty breathing, chest pain, and prolonged exhalation when breathing. There is no cure, so treatments are similar to acute bronchitis.

Chronic Obstructive Pulmonary Disease (COPD) ‐ any disease that results in obstruction (blockage) of the airways. Disorders such as chronic asthma, chronic bronchitis, emphysema, and tuberculosis can lead to COPD. Smoking is the number one cause, but allergies and chronic infections also play a role in developing COPD. Treatments include bronchodilators, mucolytics (loosen the mucus), and cough medications. COPD is a disease which usually leads to death, because it cannot be cured.


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Emphysema ‐ non‐infectious, chronic condition where Alveoli lost their elasticity (they do not work properly). This causes excess CO2 to become trapped in the lungs. The most common cause is smoking or exposure to air pollutants. Symptoms include difficulty breathing, suffocating feeling, pain, barrel chest, chronic cough, rapid and shallow breathing, eventual respiratory failure/death. There is no cure. Treatments include bronchodilators, breathing exercises, oxygen therapy, respiratory therapy and avoidance of smoking. If another respiratory infection happens, it must be treated right away to avoid complications.

Influenza (the flu) ‐ yes, the flu is actually a respiratory infection. It is highly contagious and affects the upper respiratory system. Onset is sudden and includes symptoms such as chills, fever, sore throat, cough, runny nose, muscle pain and fatigue. Treatment includes bed rest, fluids, and pain medications. Antibiotics cannot treat the flu because it is a viral infection. Immunization is possible, but it needs to be repeated every year, because there are many different viruses that can cause the flu.

Laryngitis ‐ inflammation of the larynx and vocal chords. Symptoms include hoarseness, loss of voice, sore throat and difficulty swallowing. Treatment includes rest, lots of fluids and limited voice use.

Lung Cancer ‐ leading cause of cancer death in both males and females. It is also largely preventable because the cause is smoking or second hand smoke. In the early stage there are no symptoms. In the later stages symptoms include a chronic cough, coughing up blood, difficulty breathing, fatigue, weight loss, and chest pain. Many lung cancer patients do not survive, because it is caught too late. Treatment involves surgery to remove the damaged section of lung, radiation, and chemotherapy.

Rhinitis (nose cold)‐ inflammation of the nasal mucous membrane. Runny nose, watery eyes, sneezing, soreness and congestion are the symptoms. Common causes are infections and allergens. Treatment consists of fluids and medications to relieve congestion.

Sinusitis ‐ inflammation of the mucus membrane of the sinuses. One or more sinuses may be affected. Usually caused by a bacteria or a virus. Symptoms include headache or pressure, dizziness, thick nasal discharge, congestion, and "nasaly voice". Treatment includes pain medications, antibiotics, decongestants, and moist inhalations (humidifier). Surgery is used in cases of chronic sinusitis to open the cavities and encourage drainage.


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Sleep Apnea ‐ a condition where a person stops breathing while they are asleep, and it disrupts the sleeping patterns. First kind is obstructive sleep apnea which is caused by the tongue relaxing and blocking the airway. Second is central sleep apnea which is caused by a disorder in the respiratory control center of the brain. Sleep apnea is more common in men. It is diagnosed when more than 5 periods of apnea lasting at least 10 seconds each occur during a 1 hour period of sleep. The apnea reduces the blood oxygen level, which causes the brain to wake up the person so they can gasp for air (snore). The constant interruption of the sleep cycle leads to excessive tiredness or drowsiness throughout the day. Treatment usually involves controlling weight, abstaining from alcohol, and sleeping on the side or stomach. In more severe cases, a mask may need to be worn to help keep the airway open during sleep. Treatment of central sleep apnea also may include the use of medication to stimulate breathing.

Tuberculosis (TB) ‐ infectious lung disease caused by a specific bacteria. The bacteria may infect the lungs and become surrounded by white blood cells to fight them off, which can create nodules in the lungs called tubercles. These tubercles can sometimes remain dormant in the lungs until later (usually when the immune system is weakened by another infection). Symptoms of an active case of TB include fever, fatigue, night sweats, weight loss, coughing up blood, and chest pain. Treatment includes taking medications for one or more years to destroy the bacteria. Good nutrition and rest are also important. In recent years, TB has made a comeback, and it has shown to be resistant to certain medications.

Upper Respiratory Infection (common cold) ‐ inflammation of the mucus membrane lining of the upper respiratory tract. Caused by viruses and highly contagious. Symptoms include fever, runny nose, watery eyes, congestion, sore throat, and hacking cough. There is no cure, and symptoms typically last about one week. Pain medications, rest, increased fluids, and antihistamines (for congestion) are used to treat the symptoms.

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Respiratory System Notes 20 Respiratory... · Respiratory System Notes 2 ... The cartilage part of the rings keeps our trachea open during breathing, despite ... bunch of grapes