Respiratory System and Oxygen Therapy Notes

Respiratory System

• The respiratory system involves the movement of gases into and out of the lungs (oxygen and carbon dioxide).
• Key organs: Bronchiole, Trachea, Bronchus, Alveolus, and Diaphragm.

Ventilation

• Ventilation is the process of moving gases (O2 and CO2) into and out of the lungs.
• Breathing in and out is ventilation.

Perfusion

• Perfusion is the blood flow to the alveolar capillaries.
• This blood flow transports oxygenated blood to the body’s tissues.

Poor Ventilation and Perfusion

• Poor ventilation and perfusion are significant issues that can impair oxygen and carbon dioxide exchange.

Hypoventilation

• Reduced rates of respiration.
• Reduced depth of respiration.
• Leads to:
  • Lower amount of O2 entering the body.
  • Higher concentration of CO2 remaining in the body (Hypercapnia).

Hypoventilation Consequences

• Hypercapnic Respiratory Failure (Ventilation Failure).
• Hypoxia and Hypoxemia.
• Respiratory and Cardiac Arrest.
• Causes: Medications, anesthesia, or diseases (COPD, Sleep Apnea).

Hypoxia vs. Hypoxemia

• Hypoxemia: Low level of oxygen in the blood.
• Hypoxia: Failure of oxygenation at the tissue level (tissues aren’t receiving enough O2, i.e., aren't being perfused).

Increased Oxygen Needs

• Metabolic Demands: Exercise, pregnancy, digestion of a large meal.
• Body Temperature: Febrile conditions.
• Emotions: Anxiety, fear.
• Sympathetic Autonomic Nervous System: Stress.

Pulse Oximetry

• Measures the amount of hemoglobin in the blood saturated with oxygen.

• Higher saturation % indicates more hemoglobin is saturated with O2.

• Cannot distinguish different forms of oxygen that bind to hemoglobin.

• Carbon Monoxide (CO) can bind to hemoglobin, leading to carbon monoxide poisoning, which can still indicate a “good” oxygen saturation reading.

  • Importance of thorough health history and physical exam.

COPD Refresher

• Chronic Obstructive Pulmonary Disease (COPD) is a lung condition that makes it hard to breathe out fully, leading to CO2 build-up in the blood over time (hypercapnic).

• COPD patients often have higher than normal CO2 levels.

• Their body stops using CO2 levels as the main signal for when to breathe; instead, the brain starts using oxygen levels.

  • Low O2 levels signal the body to breathe.
  • Normal pulse oximetry range for COPD Patients: 88-92%.

Hypoxia

• Hypoxia is a medical emergency and must be addressed immediately!

Signs and Symptoms of Hypoxia

• (CNS):
  • Unexplained Apprehension
  • Unexplained restlessness or irritation
  • Unexplained confusion or lethargy
  • Combativeness
  • Coma
• (Respiratory):
  • Tachypnea
  • Dyspnea on exertion
  • Dyspnea at rest
  • Use of accessory muscles
  • Retraction of interspaces on inspiration
  • Pausing for breath midsentence
  • Pursed Lip Breathing
• (Cardiovascular):
  • Tachycardia
  • Mild Hypertension
  • Dysrhythmias
  • Hypotension
  • Cyanosis
  • Cool, Clammy Skin
• (Other Body Systems):
  • Diaphoresis
  • Decreased Urinary Output
  • Unexplained Fatigue

Causes of Hypoxia

• Lung Diseases (COPD, Infections, Severe Asthma)
• Cardiovascular Diseases (CHF, Stroke)
• Shock
• Anemia
• Smoking
• Obesity
• Certain Medications

Medications Affecting the Respiratory System

• Depressants:
  • Slow down or decrease the rate and depth of breathing: Opioids, anesthetics, muscle relaxants.
• Bronchoconstrictors:
  • Cause the airways in the lungs to narrow: Beta-Blockers, Ace Inhibitors.
• Bronchodilators:
  • Relaxes the muscles in your lungs and widens the airways: Beta-2 agonists, Anticholinergics.
• Corticosteroids:
  • Reduces inflammation and mucus production in the lungs.

Respiratory Medications: Metered-Dose Inhalers (MDIs)

• Medications are dispersed through an aerosol spray, mist, or powder that penetrates the airways.
• Dosing: Usually achieved with 1 or 2 puffs.
• Common medications: Bronchodilators and Corticosteroids.

MDI Administration

• Perform 3 Med checks and 10 Rights.
• Check 2 client identifiers at bedside before administering.
• Shake the MDI 5-6 times.
• Have client place MDI mouthpiece between teeth, with mouth sealed around it.
• Instruct them to completely exhale before depressing the canister.
• Have the client inhale through their mouth and depress the canister.
• Instruct the client to hold their breath for 10 seconds.

MDI Spacers

• A spacer is a tube or chamber that attaches to an MDI to help deliver medication to the lungs.
• Easier to use, especially for people who have trouble coordinating breathing and depressing the canister.

MDI Special Considerations

• Administer bronchodilator (e.g., salbutamol) before corticosteroid (e.g., fluticasone) to keep airways open and enhance the effects of the corticosteroids.
• Instruct client to rinse out their mouth after administering a corticosteroid MDI to prevent oral thrush and throat irritation.
• If a beta-adrenergic bronchodilator was administered, monitor pulse as it can lead to tachycardia.

Respiratory Medications: Nebulizers

• Nebulization is a treatment that involves turning liquid medication into a mist that a patient inhales through a mask or mouthpiece.
• The mist is delivered into the lungs through the airway.

When to Use a Nebulizer Over an Inhaler

• Difficulty with Inhaler Technique: Young children, the elderly, or individuals with limited dexterity.
• Acute or Severe Symptoms: Acute asthma exacerbations or severe respiratory distress; nebulizers can deliver higher doses of medication more effectively.
• Multiple Medications: Allows for combined delivery of treatments.
• Chronic or Serious Respiratory Conditions: COPD or severe asthma; nebulizers may provide more consistent and comprehensive management.

Nebulizer Administration

• Perform 3 Med checks and 10 Rights.
• Check 2 client identifiers at bedside before administering.
• Pour prescribed medication in the nebulizer cup.
• Attach cup and secure to face mask.
• Attach tubing to aerosol compressor and nebulizer cup OR connect tubing to oxygen/medical air connection
• Place mask on client.
• Turn on compressor/administer oxygen.
• Instruct client to take slow, deep breaths.
• Nebulizers typically take 10-15 minutes to be administered.
• Remove mask and turn off compressor.

Nebulizer Special Considerations

• Nebulizers can also be administered through a mouthpiece instead of a mask.
• If a corticosteroid has been given through nebulization, instruct client to rinse out their mouth to prevent risk of oral thrush.
• If a beta-adrenergic bronchodilator (salbutamol) was administered, monitor pulse as it can lead to tachycardia.

Oxygen Therapy

• Oxygen is required for life and cell function.

• Oxygen is measured in FiO2 (fraction of inspired oxygen), which is the percentage of oxygen in inhaled air.

• Room air is about 21% oxygen, so without supplemental oxygen, a person's FiO2 is 21%.

• Measured in Liters per minute (L/min).

  • L/min is the flow rate of oxygen delivered to a patient.
  • General rule of thumb: for every liter of oxygen supplied, the FiO2 increases by about 4%.

Oxygen Flow and Approximate FiO2

• 1 L/min ≈ 24% FiO2
• 2 L/min ≈ 28% FiO2
• 3 L/min ≈ 32% FiO2
• 4 L/min ≈ 36% FiO2
• 5 L/min ≈ 40% FiO2
• 6 L/min ≈ 44% FiO2
• 7 L/min ≈ 48% FiO2
• 8 L/min ≈ 52% FiO2
• 9 L/min ≈ 56% FiO2
• 10 L/min ≈ 60% FiO2

Oxygen Therapy in Hospital Settings

• Oxygen flow meter typically goes up to 15L/min = 80% FiO2.

• The appropriate flow rate depends on the doctor's clinical picture.

• Higher flow rates (10-15L/min) are typically used on clients with severe respiratory conditions or in emergency situations.

• LPNs require a doctor's order to administer O2- unless it is an emergency situation!

• Oxygen administration can be misused and can lead to harm to the client.

  • MORE is not always better.

Oxygen Toxicity

• Oxygen toxicity, caused by excessive or prolonged oxygen use, can damage the lungs and other organs.
• High oxygen levels increase free radicals, leading to lung injuries like tracheobronchitis or alveolar damage.
• Those at particular risk for oxygen toxicity include hyperbaric oxygen therapy patients, patients exposed to prolonged high levels of oxygen, premature infants, and underwater divers.
• Symptoms include coughing and shortness of breath.
• To avoid these effects, oxygen should be given at the lowest effective dose to maintain target saturation levels.

Nasal Cannula

• Administers a flow rate between 1/4 - 6 L/min of oxygen.
• Tubing goes behind the ears from the front and does NOT encircle the neck!

Simple Face Mask

• Covers the mouth and nose.
• Administers between 5- 10L/min.
• Important not to administer a flow rate lower than 5L/min, as this could lead to rebreathing carbon dioxide.

Non-Rebreather Mask

• Delivers the highest FiO2, 60-100% at flows of 10-15 L/min by means of a one-way valve on the mask.
• This valve prevents the room air and client’s exhaled air from entering the bag so that only the oxygen is the bag is inspired.
• Decreases the risk of rebreathing.

Oxygen Humidification

• Used to add moisture to oxygen to reduce the drying effects of oxygen on the respiratory tract.
• Helps relieve congestion, reduce feelings of breathlessness, and reduce the risk of infection.
• The humidification bottle is typically attached to the bottom of the flow meter.
• Sterile water is used to create the humidification.

Prior to Administering Oxygen Therapy

• Check the prescriber’s orders, including flow rate, whether continuous or PRN, delivery method, and any associated lab or diagnostic tests.
• Check to see if the client has COPD or if oxygen level must be otherwise regulated down in flow.
• Check oxygen saturation with a pulse oximeter and respiration rate and pattern.
• Know the client’s normal vital signs and usual behavior, orientation, and responsiveness.
• Understand more by checking blood tests, such as hemoglobin level, ABG, and any diagnostic tests, such as X-ray and bronchoscopy reports.

Administering Oxygen Therapy

• Check for any changes/updated orders.
• Assemble appropriate supplies.
• Explain procedure to the patient and perform hand hygiene.
• Assemble the device and connect it to the flow meter; if water (humidification) is used, these must be changed every 48 hours.
• Adjust the flow rate to match oxygen order.
• Place on the patient’s face snugly but not tightly, ensuring comfort and tolerance.
• If using a non-rebreather system, adjust the flow to the level which just maintains an inflated reservoir bag during inspiration but no greater (excess flow rate may increase work of breathing).
• Document initiation of oxygen therapy, client effect and tolerance.

Oxygen Safety Considerations

• Check oxygen dose, skin and equipment at least q 8 hours or as per agency policy. Oxygen delivery devices (Nasal Cannulas, Face Masks) are common causes of pressure sores.
• Oxygen is a medication and requires an order and the 10 rights of medication administration.
• Oxygen is highly flammable and the delivery system must be kept away from any open flame. Keep away from other flammable materials as well, including petroleum jelly (Vaseline), and oils.

Other Respiratory Interventions

• Incentive spirometry, positioning, sputum C+S, and oropharyngeal suctioning.

Incentive Spirometry

• An incentive spirometer is a handheld device used to help clients practice taking slow, deep breaths, which is particularly beneficial after surgery or when dealing with lung illnesses like pneumonia.
• Helps prevent complications by keeping the lungs inflated and clear of fluid build-up by encouraging proper lung expansion through deep breathing exercises.
• How to use:
  1. Sit up straight.
  2. Exhale normally.
  3. Place the mouthpiece in your mouth and close your lips around it.
  4. Breathe in slowly and deeply through the mouthpiece.
  5. Hold your breath for a few seconds.
  6. Remove the mouthpiece and breathe out normally.
  7. Repeat as instructed by the physician.

Positioning

• A client’s position can have a large effect on their breathing patterns.
• If your client is demonstrating signs and symptoms of respiratory distress, ensure they are positioned in a position that allows for maximal lung expansion.

Sputum C+S

• A Sputum Culture and Sensitivity (C+S) is a test that collects a client's sputum to identify any bacteria (culture) that may be causing a lung infection.
• Assesses which antibiotics would be effective in treating the bacteria (sensitivity).
• Collection:
  1. Early morning sputum samples are preferable, but samples collected at other times of the day are also acceptable. Sputum is material brought up from as far down in the lungs as possible after a deep cough. It is not saliva.
  2. Use container provided by physician for collection.
  3. Complete the information requested on the container label. Including the clients name, the ordering physician, and the date and time of collection.
  4. Remove the container cap.
  5. After a big cough, collect the sputum into the provided empty container.
  6. Replace the cap and tighten firmly.
  7. Keep the sputum sample refrigerated until it is taken to the laboratory. Take the specimen to the laboratory as soon as possible.

Oropharyngeal Suctioning

• A medical procedure where a suction catheter is inserted into the mouth to remove mucus or saliva from the back of the throat (oropharynx) of a patient who is unable to clear their secretions themselves.

  • Typically due to being unconscious, sedated, or having impaired swallowing ability.

• Involves using suction to clear the airway in the throat area by accessing it through the mouth.

• Why provide oropharyngeal suction?

  • To clear secretions from the oral pharynx
  • To maintain a patent airway and avoid aspiration of food material

• When should we provide oropharyngeal suctioning?

  • When a patient is known to be an aspiration risk and there are visible secretions needing to be removed
  • When a patient indicates distress and signs of choking or difficulty managing airway, breathing while eating and can’t manage clearing/coughing on their own with support

Performing Oropharyngeal Suctioning

• Get a fresh (packaged) Yankauer catheter and attach tubing to suction (wall or machine)
• Get a cup of clean water or normal saline to lubricate catheter and clean tip during procedure
• Turn on the machine an set the suction to: (adult) 80-120 mmHg or Facility policy (children are never above 100 mmHg)
• Use disposable non-sterile gloves
• Dip the catheter tip in the clean water or NS to check suction of Yaunker
• Begin suctioning quickly, gently, BRIEFLY
• If a second person is available, they should monitor respiratory condition, including pulse oximeter readings. Remember, you are suctioning oxygen from a person – keep your suctioning time BRIEF!
• After suctioning, encourage client to breathe deeply and reoxygenate as necessary before moving
• Clean area, disposing of catheter per agency policy

Oropharyngeal Suctioning Safety Considerations

• Suctioning can lead to decrease oxygenation, leading the client to de-sat… keep suctioning time SHORT! And reapply oxygen as needed. Check oxygen saturation throughout.
• Avoid oral suctioning on patients with recent head and neck surgeries.
• Use clean technique and keep suction tip clean and lubricated with water.
• Always perform a PRE and POST suction respiratory assessment.