Oxygenation

Oxygenation Notes: Simplified for Beginners
How We Breathe: A Look Inside

  • Airway Parts: These are the tubes and spaces air travels through:

    • Frontal sinus (air-filled space in forehead)

    • Sphenoidal sinus (air-filled space behind the nose)

    • Nasal cavity (inside your nose)

    • Pharynx (throat)

    • Larynx and vocal cords (voice box)

    • Esophagus (food pipe, behind the windpipe)

    • Trachea (windpipe)

    • Alveolar duct (small tubes leading to air sacs)

    • Alveoli (tiny air sacs in the lungs where gas exchange happens)

    • From pulmonary artery to pulmonary vein (blood vessels around the lungs)

    • Right lung and right bronchus (main air tube to the right lung)

    • Left lung and its components (left lung and its main air tube)

    • Mediastinum (space between the lungs, containing heart, etc.)

    • Thoracic vertebrae (backbones in the chest area)

    • Diaphragm (main breathing muscle below the lungs)

    • Wall of thorax (rib cage and chest muscles)

    • Pleura (thin layers covering the lungs and chest wall):

      • Parietal pleura (outer layer, lining the chest wall)

      • Visceral pleura (inner layer, covering the lungs)

      • Pleural space (small space between the two pleural layers)

    • Capillaries (tiny blood vessels around the air sacs)

Important Breathing Structures

  • Key Elements:

    • Cilia: Tiny, hair-like structures in your airways that sweep out mucus and dirt.

    • Alveoli: The tiny air sacs in your lungs where oxygen enters the blood and carbon dioxide leaves it.

    • Surfactant: A special liquid in the alveoli that prevents them from collapsing.

What Breathing Does

  • Defining Key Actions:

    • Pulmonary Ventilation: Simply moving air into and out of your lungs (breathing in and out).

    • Respiration: This is the exchange of gases. It’s when oxygen from the air sacs (alveoli) goes into your blood, and carbon dioxide from your blood goes back into the air sacs to be breathed out.

    • Perfusion: The process where oxygen-rich blood from the capillaries (tiny blood vessels) is delivered to all the body's tissues.

    • Inspiration (Breathing In): An active process where muscles (like the diaphragm) contract to pull air into the lungs.

    • Expiration (Breathing Out): A mostly relaxed, passive process where the lungs' natural elasticity pushes air out.

How Gases Swap Places

  • The Swap Mechanism:

    • Gases move between the tiny air sacs (alveoli) and blood vessels (capillaries).

    • Gases want to move from an area where there's a lot of them to an area where there's less. This is called partial pressure.

      • Exhaled air (what you breathe out):

        • Carbon dioxide (PCO2) = 46 mm Hg (more CO2)

        • Oxygen (PO2) = 40 mm Hg (less O2)

      • Alveolus (air in your lungs):

        • Carbon dioxide (PCO2) = 40 mm Hg (less CO2, so it moves out)

        • Oxygen (PO2) = 100 mm Hg (more O2, so it moves in)

How Breathing is Controlled

  • The Brain's Role (Medulla):

    • Your brainstem, specifically the medulla, controls your breathing rate and depth automatically.

    • Chemoreceptors: Special sensors in major arteries (aortic arch and carotid arteries) detect changes in oxygen and carbon dioxide levels in your blood and tell the medulla to adjust your breathing.

Things That Affect Gas Exchange

  • Factors influencing how well gases move:

    • Change in surface area: If less lung area is available (e.g., collapsed lung), less gas exchange occurs.

    • Atelectasis: This is when parts of your lung, or even a whole lung, collapse. This greatly reduces the surface area for gas exchange.

    • Thickening of the alveolar-capillary membrane: If the thin barrier between air sacs and blood vessels gets thicker (due to disease), gases have a harder time crossing.

    • Disease states: Conditions like pneumonia or emphysema can damage the lungs and reduce gas exchange.

    • Partial pressure variances: If the difference in gas amounts between the air and blood isn't big enough, gases won't move as effectively.

How Oxygen Travels in the Body

  • Oxygen's Journey:

    • Oxygen is carried in your blood, partly dissolved in the plasma (liquid part of blood) and mostly by red blood cells.

    • Oxyhemoglobin: Oxygen attaches to hemoglobin (a protein in red blood cells), forming oxyhemoglobin, which gives blood its red color.

    • Carboxyhemoglobin: If carbon monoxide is inhaled, it can attach to hemoglobin instead of oxygen, forming carboxyhemoglobin, which is very dangerous.

    • Internal respiration: This is when oxygen leaves the blood and enters your body's tissues, and carbon dioxide leaves the tissues and enters the blood.

What Can Affect Oxygenation

  • Factors impacting how well your body gets oxygen:

    • Health Status: Certain health conditions can make breathing difficult.

    • Environmental Factors: Air pollution, high altitudes, or very cold air can affect breathing.

    • Lifestyle Choices: Smoking, lack of exercise, or poor diet can harm lung function.

    • Effects of Medications (like opioids): Some drugs can slow down your breathing, making it harder to get enough oxygen.

    • Growth and Development Stage: Babies, children, and older adults have different respiratory needs and risks.

    • Conditions like Kyphosis: A severe curve in the upper spine can restrict lung expansion.

Who is at Higher Risk for Breathing Problems

  • Groups with higher risk:

    • Very young and very old individuals: Their respiratory systems may be less developed or weaker.

    • Administration of narcotics (e.g., demerol, morphine, dilaudid): These pain medications can significantly slow breathing.

    • Lifestyle factors: Smoking (damages lungs), lack of exercise (weakens breathing muscles).

    • Environmental pollutants: Exposure to harmful substances like those from coal mining or asbestos can cause lung disease.

    • Psychological factors: Severe anxiety or panic attacks can lead to rapid, shallow breathing.

    • Physical issues: Muscle weakness, curved spine (scoliosis, kyphosis), or obesity can make breathing harder.

    • Blood conditions: Anemia (not enough healthy red blood cells) means less oxygen can be carried.

    • Myocardial infarction (MI) history: A past heart attack can affect the heart's ability to pump blood, impacting oxygen delivery.

Nursing Role: Checking Oxygenation

  1. Assessing Oxygenation:

    • Gathering health history: Asking about past breathing problems, surgeries, or family history.

    • Key questions: Asking about cough, shortness of breath, chest pain, and what makes symptoms better or worse.

Doing a Physical Check

  • Ways to check breathing:

    • Inspection (Looking):

      • Looking for signs of trouble breathing (shortness of breath, difficulty breathing, cough, mucus production, tiredness, fever).

      • Checking chest shape and skin color (pale, bluish).

      • Seeing if accessory muscles (neck and shoulder muscles) are being used for breathing (which means working harder).

      • Counting how fast (rate) and how regular (rhythm) someone is breathing.

      • Measuring pulse oximetry (Pulse O2 level): A non-invasive way to check the oxygen level in the blood using a finger clip; a healthy reading is usually above 94\%.

  • Palpation (Feeling) and Auscultation (Listening):

    • Tactile fremitus assessment: Feeling vibrations on the chest when the patient speaks.

    • Auscultate for adventitious lung sounds: Listening with a stethoscope for unusual or abnormal lung sounds.

Signs of Oxygen Problems

  • Symptoms to watch for:

    • Hypoxia: Not enough oxygen reaching the body's tissues.

      • Early signs: Restlessness, anxiety, fast heart rate, fast breathing.

      • Late signs: Bluish skin (cyanosis), very slow heart rate, confusion.

    • Chronic hypoxia: Long-term low oxygen, often leads to fatigue, clubbing of fingers (enlarged fingertips).

    • Hypoventilation (Bradypnea): Breathing too slowly or shallowly, leading to too much carbon dioxide in the blood (hypercapnia/hypercarbia).

    • Hyperventilation (Tachypnea): Breathing too fast, leading to too little carbon dioxide in the blood.

    • Dyspnea: Difficulty breathing or shortness of breath.

    • Airway obstruction: Something blocking the airway.

    • Cyanosis: Bluish discoloration of skin, lips, or nail beds due to lack of oxygen (a late sign of hypoxia).

    • Hemoptysis: Coughing up blood.

    • Orthopnea: Difficulty breathing when lying flat, needing to sit up to breathe.

    • Pulmonary friction rub: A creaking or grating sound heard when the layers of the pleura rub together, usually due to inflammation.

Normal Sounds When You Breathe

  • Healthy Breath Sounds:

    • Vesicular: Soft, low-pitched sounds heard over most lung areas during expiration.

    • Bronchial: Loud, high-pitched sounds heard primarily over the trachea (windpipe).

    • Bronchovesicular: Medium-pitched sounds heard over the upper chest and between the ribs.

Abnormal Sounds When You Breathe

  • Unusual Breath Sounds:

    • Crackles (Rales): Brief, crackling, popping sounds, like hair rubbing together, often indicating fluid in the airways. Can be fine, medium, or coarse.

    • Wheezes: High-pitched, whistling or squeaking sounds, usually heard during expiration, caused by narrowed airways. Can be sibilant (musical) or sonorous (snoring-like).

    • Pulmonary Friction Rub: A rough, grating, or creaking sound, like leather rubbing together, caused by inflamed pleural layers rubbing against each other.

    • Stridor: A harsh, high-pitched, crowing sound, usually heard on inspiration. It's a sign of a severe blockage in the upper airway and is a medical emergency.

Tests to Check Lungs

  • Tests for Oxygenation:

    • Pulmonary Function Studies (PFT): Tests to measure how well your lungs are working.

      • Spirometry: Measures how much air you can breathe in and out, and how quickly.

      • Peak Expiratory Flow Rate: Measures the fastest rate you can exhale air.

      • Pulse Oximetry: (As mentioned before) A quick check of oxygen levels in your blood.

    • Sputum Samples: Testing mucus you cough up.

      • Cytology: Looking for abnormal cells.

      • Culture and Sensitivity (C & S): Identifying bacteria and finding out which antibiotics will work best.

      • Acid Fast Bacillus (AFB): To check for tuberculosis.

      • Throat cultures: Swabbing the throat to test for infections.

    • Visualization Procedures: Looking inside the body.

      • Bronchoscopy: A thin tube with a camera is inserted into the airways to look directly at the bronchi and take samples.

      • Imaging tests: Pictures of your lungs like Chest X-rays, CT scans (more detailed X-ray), spiral CT (for blood clots), and MRI (uses magnets to create images).

    • Lung Scan: Uses a small amount of radioactive material to check blood flow (perfusion) and air distribution (ventilation) in the lungs. Known as V-Scan, Q-Scan, or VQ Scan.

    • Thoracentesis Procedure: Removing fluid from the pleural space (between the lung and chest wall) using a needle and syringe.

    • Arterial Blood Gases (ABG): A blood sample taken from an artery (usually in the wrist) to measure oxygen, carbon dioxide, and pH levels in the blood, giving a precise look at gas exchange.

Nursing Problem Statements (Diagnoses)

  • Common Nursing Diagnoses for breathing issues:

    • Ineffective airway clearance (trouble clearing mucus from airways).

    • Ineffective breathing pattern (abnormal way of breathing).

    • Impaired gas exchange (trouble swapping oxygen and carbon dioxide).

    • Impaired spontaneous ventilation (trouble breathing on their own).

What Nurses Aim For (Patient Goals)

  • Examples of goals for patients:

    • Patient will show better gas exchange, with no bluish discoloration (cyanosis).

    • Patient's oxygen saturation (pulse oximetry) will stay above 94\%.

    • Patient will use three actions that help them breathe easier.

How Nurses Can Help Breathing

  • Nursing Actions:

    • Positioning: Placing the patient in positions that allow for the best lung expansion (e.g., sitting upright) and changing positions often to prevent fluid buildup.

    • Pursed lip breathing: A technique where patients breathe in through the nose and slowly exhale through pursed lips, helping to keep airways open longer.

    • Incentive Spirometry (IS): A device that encourages patients to take deep breaths, helping to expand the lungs and prevent complications like atelectasis.

    • Humidification and Nebulization treatments: Adding moisture to inhaled air or delivering medication as a fine mist to loosen mucus and open airways.

    • TCDB (Turn, Cough, Deep Breath) methods: Encouraging patients to move, cough deeply, and take deep breaths to clear airways and prevent lung collapse.

    • Vaccines: Encouraging flu and pneumonia vaccines to prevent respiratory infections.

Medicines for Breathing Problems

  • General Approach: First, give oxygen if needed. Then, follow doctor's orders for specific medicines. Remember to measure the patient's oxygen level using pulse oximetry.

  • Types of Medications:

    • Expectorants: Help thin mucus so it's easier to cough up (e.g., Guaifenesin/Mucinex).

    • Cough suppressants: Reduce coughing (used for dry, irritating coughs).

    • Lozenges: Soothe sore throats and coughs.

    • Device Use:

      • DPI (Dry Powder Inhaler): Delivers medication as a dry powder when you inhale.

      • MDI (Metered Dose Inhaler): Delivers a specific puff of medication as a mist.

    • Specific Medications for Airways:

      • Beta-agonists/bronchodilators: Relax muscles around the airways to open them up, relieving wheezing and shortness of breath.

        • Short-acting: Albuterol, Proventil (for quick relief).

        • Long-acting: Serevent (for longer-lasting control).

      • Inhaled corticosteroids: Reduce swelling (inflammation) in the airways (e.g., Flovent, Pulmicort).

      • Leukotriene antagonists: Block substances in the body that cause airway swelling and constriction (e.g., Singulair).

      • Anticholinergics: Help relax and open airways by blocking certain nerve signals (e.g., Spiriva).

    • Caution: Opioid pain medications (e.g., Percocet, Morphine, Fentanyl) can dangerously slow down breathing. Use with care, especially if a patient already has breathing issues.

Giving Oxygen Therapy

  • How Oxygen is Given:

    • Oxygen is ordered by a doctor with specific flow rates (how much oxygen per minute, e.g., 1 to 6 L/min) and FIO2 (the percentage of oxygen the patient is breathing, compared to room air which is 21%).

    • **Oxygen delivery methods:

      • Nasal Cannula: A small tube placed just inside the nostrils. Good for low flow rates (1 to 6 L/min), providing 24\% to 44\% oxygen.

      • Face Masks: Cover the nose and mouth.

        • Simple face mask

        • Partial rebreather mask

        • Non-rebreather mask (delivers high concentrations of oxygen)

        • Venturi mask (delivers very precise amounts of oxygen).

      • Aerosol masks and face tents: Used for patients who need humidified oxygen or cannot tolerate other masks.

    • Special Considerations for COPD Patients:

      • Oxygen is combustible (can feed fire), so avoid open flames.

      • For people with COPD (Chronic Obstructive Pulmonary Disease), giving too much oxygen can actually reduce their drive to breathe, as some COPD patients use a low oxygen level as their signal to breathe. Higher levels of oxygen can be dangerous for them.

      • Be aware of oxygen toxicity (harmful effects from too much oxygen) and hypoventilation risks (breathing too slowly).

Breathing Machines: CPAP and BiPAP

  • CPAP (Continuous Positive Airway Pressure): Delivers a steady stream of air pressure to keep the upper airway open, often used for sleep apnea to prevent airway collapse during sleep.

  • BiPAP (Bi-level Positive Airway Pressure): Delivers two levels of air pressure (higher for breathing in, lower for breathing out), helping to increase the amount of air in the lungs and make breathing easier.

Chest Tube Care

  • Why Chest Tubes are Needed:

    • To drain fluid (pleural effusion), blood (hemothorax), or air (pneumothorax) from the space around the lungs (pleural space), which can prevent the lung from expanding.

  • Nurse's Role for Chest Tubes:

    • Monitoring: Check the chest tube drainage system regularly to ensure it's working correctly and that the water seal (a safety mechanism) is maintained.

    • Maintenance: Make sure the tubes are not kinked or blocked.

    • Dressing care: Change the dressing around the insertion site every two days, keeping it clean and dry.

Clearing Mucus from Airways

  • Ways to Remove Mucus:

    • Adequate hydration: Drinking enough water helps thin mucus.

    • Purposeful coughing: Teaching patients how to cough effectively to clear secretions.

    • Chest physiotherapy or positioning: Specific techniques to loosen and move mucus.

    • Suctioning: If other methods don't work, a tube is inserted into the airway to suction out mucus.

    • Humidification: Adding moisture to the air to keep airways from drying out and to thin mucus.

Chest Physiotherapy (CPT)

  • CPT Techniques: Special physical techniques used to help loosen and remove mucus from the lungs, improving breathing and coughing.

  • How to do CPT:

    • Percussion: Cupping your hand and gently clapping on the chest or back over the lung areas to create vibrations that shake mucus loose.

    • Vibration: Placing hands flat on the chest wall during exhalation and gently vibrating to help move mucus.

    • Postural Drainage: Positioning the patient in different ways (e.g., lying on side, head down) to use gravity to help mucus drain from different parts of the lungs. Often most effective in the morning.

Artificial Airways

  • Types of Airways When Natural Breathing is Hard:

    • Oropharyngeal airway: A curved device inserted into the mouth to keep the tongue from blocking the airway in unconscious patients.

    • Nasopharyngeal airway: A soft tube inserted through the nose into the back of the throat to keep the airway open. Nurses can often insert these.

    • Endotracheal Tubes: A tube inserted through the mouth or nose directly into the trachea (windpipe) to connect a patient to a ventilator or bypass an airway obstruction. Only trained professionals insert these.

    • Tracheostomy: A surgical opening made directly into the trachea in the neck, with a tube inserted. This is done for long-term breathing support or when the upper airway is blocked. It requires careful care, keeping the area clean, and managing mucus.

Checking on Tracheostomy Patients

  • What to Assess:

    • Breath sounds: Listening to the lungs.

    • Respiratory rates: How fast they are breathing.

    • Oxygen saturation: Oxygen levels in the blood.

    • Coughing secretions: Amount and type of mucus being coughed up.

    • Suctioning needs: Determining if mucus needs to be removed.

    • Skin integrity: Checking the skin around the tracheostomy site for irritation or infection.

Taking Care of a Tracheostomy

  • Tracheostomy Care:

    • Suctioning Precautions: Always use sterile technique (clean gloves, sterile equipment) when suctioning. Before suctioning, give the patient extra oxygen (pre-oxygenate). Suction only for short periods and intermittently (on and off) to avoid harming the airway.

    • Emergency Procedures: If the tracheostomy tube accidentally comes out (decannulation), especially within the first 72 hours after placement, it's a medical emergency! Quickly ensure that manual ventilation (bagging the patient) is available and call for help immediately.

Conclusion: These notes cover the basics of oxygenation, from how our body breathes to common problems, tests, medications, and nursing care, all explained in a way that should be easier to understand for someone new to the topic.