Chapter 2 Respiratory System PDF

Respiratory System  What is Respiration? Respiration occurs when a person inhales (oxygen is taken into the body) and then exhales (carbon dioxide [CO2] is expelled from the body). Respiration involves the — Airway. The airway consists of the nose, mouth, throat, voice box, and windpipe. It is...

Respiratory System  What is Respiration? Respiration occurs when a person inhales (oxygen is taken into the body) and then exhales (carbon dioxide [CO2] is expelled from the body). Respiration involves the — Airway. The airway consists of the nose, mouth, throat, voice box, and windpipe. It is the canal through which air passes to and from the lungs. Respiration involves cont’d 2. Lungs. The lungs are two elastic organs made up of thousands of tiny air spaces and covered by an airtight membrane. The bronchial tree is a part of the lungs. 3. Rib cage. The rib cage is formed by the muscle connected ribs, which join the spine in back, and the breastbone in front. The top part of the rib cage is closed by the structure of the neck, and the bottom part is separated from the abdominal cavity by a large dome-shaped muscle called the diaphragm. Respiration involves cont’d The diaphragm and rib muscles, which are under the control of the respiratory center in the brain, automatically contract and relax. Contraction increases and relaxation decreases the size of the rib cage. When the rib cage increases and then decreases, the air pressure in the lungs is first less and then more than the atmospheric pressure, thus causing the air to rush into and out of the lungs to equalize the pressure. This cycle of inhaling and exhaling is repeated about 12 to 18 times per minute. Air way, Lungs and Rib cage Respiratory Tract 1. Upper Respiratory Tract: o Nasal Cavity: Warms, filters, and humidifies air before it reaches the lungs. The mucus and cilia present in the nasal cavity trap particles to prevent infection. o Pharynx: Passage for both food and air. It divides into the esophagus (for food) and the trachea (for air). o Larynx: Houses the vocal cords and plays a role in breathing, sound production, and protecting the trachea from food aspiration.  Respiratory Tract 2. Lower Respiratory Tract: Trachea: The windpipe that carries air from the larynx to the bronchi. Bronchi and Bronchioles: These tubes carry air into each lung. They branch into smaller bronchioles, which lead to the alveoli. Alveoli: Tiny air sacs where oxygen from inhaled air is exchanged for carbon dioxide, which is exhaled. Alveoli are surrounded by a network of capillaries that facilitate this gas exchange. Respiratory Tract 3. Diaphragm: A large muscle at the base of the lungs that contracts and relaxes to enable breathing. When it contracts, the chest cavity expands, and air is drawn into the lungs (inhalation). When it relaxes, air is expelled (exhalation).  Air Passages The air passages consist of the nose Throat (pharynx) Wind pipe (trachea) Air-tubes (bronchi) Bronchioles Alveoli MECHANISM OF RESPIRATION  Inspiration (Breathing IN) The diaphragm (the muscle separating the chest from the abdominal cavity) flattens and increases the chest capacity from above downwards. The ribs move upwards and forwards increasing the capacity of the chest cavity from front to back by the action of the muscles situated between the ribs. The lungs thus expand and air enters them. This is an active process. Expiration (Breathing OUT) The reverse process takes place the diaphragm comes back to its original state and the ribs fall back thus forcing the air out of the lungs. This is a passive process. Small Blood Vessels (Capillaries) Surround the alveoli. The exchanges of oxygen and carbon dioxide take place through the blood circulating in these capillaries. Oxygen is absorbed by the red blood corpuscles of the blood; water vapor and carbon dioxide are let out from the blood plasma into the alveoli and expelled out. The lungs are also supplied with nerves which are connected to an area in the brain called respiratory center. This center controls the respiration. No Breathing OR Difficult Breathing Asphyxia is a condition in which the lungs do not get sufficient supply of air for breathing. If this continues for some minutes, the breathing and heart action stop and death occurs. A person can only survive a few minutes without breathing and a beating heart. Causes of No Breathing and Common Medical Emergencies in Dentistry  Causes of No Breathing in a Dental Clinic What Can Cause No Breathing in a Dental Setting? Airway Obstruction: Choking on dental instruments, tooth fragments, or materials. Anaphylaxis: Severe allergic reactions to medications or latex. Sedation or Anesthesia Complications: Overdose or reaction leading to respiratory depression. Vasovagal Syncope: Fainting with temporary cessation of breathing. Cardiac Arrest: Underlying heart conditions or stress during a procedure. Acute Asthma Attack: Triggered by stress or exposure to allergens. Hyperventilation: Anxiety-induced over-breathing followed by apnea. Trauma to Airway: Swelling or bleeding due to procedural trauma. How to Recognize No Breathing in Patients Cyanosis (blue lips, face, or nails) Absence of chest movement or air exchange Gasping or choking sounds Unresponsiveness or unconsciousness Struggling to breathe or high-pitched breathing (stridor) 1. Syncope (Fainting) Causes :Typically caused by a drop in blood pressure  Symptoms: Pale skin, dizziness, sweating, loss of consciousness. Lightheadedness, nausea, sweating.  Immediate Action: o Positioning: Lay the patient flat and elevate their legs to improve blood flow to the brain. o Airway: Ensure the airway is clear and monitor vital signs. Administer oxygen if needed. o Recovery: Once consciousness is regained, keep the patient lying down for a few minutes and check for underlying causes. Follow-Up: If fainting is recurrent, refer the patient for further evaluation. 2.Airway Obstruction in Dentistry Causes: Inhalation of dental tools, tooth fragments, or dental materials. Signs: Gagging, choking, cyanosis, inability to speak. First Aid: Encourage coughing if patient is conscious. Perform Heimlich maneuver if choking persists. Call for emergency help if unresolved. Start CPR if patient becomes unresponsive Follow-up: Ensure no foreign objects remain in the airway, X-ray may be needed to rule out aspiration. Heimlich Maneuver 3.Anaphylaxis Causes :A severe allergic reaction that can cause difficulty breathing and other symptoms Symptoms: Rapid onset of hives, swelling of the face or throat, difficulty breathing, abdominal pain, or shock., wheezing, swelling of the face or throat, abdominal pain. Immediate Action: Epinephrine: Administer 0.3–0.5 mg of epinephrine (auto-injector usually intramuscularly in the mid-thigh ) for adults, or 0.01 mg/kg for children, in the mid-thigh. Positioning: Keep the patient lying down with their legs elevated if possible. Oxygen: Provide supplemental oxygen if available. Emergency Services: Call for immediate medical assistance. Follow-Up: Monitor for recurrent symptoms and be ready to administer a second dose of epinephrine if needed. 4.Sedation or Anesthesia Complications Respiratory Depression Due to Sedation or Anesthesia Causes: Overdose or adverse reaction to sedatives or anesthetics. Signs: Slow or absent breathing, cyanosis, unconsciousness. First Aid: Ensure the airway is open. Administer oxygen. Start CPR if necessary. Call emergency services. Follow-up: Evaluate anesthesia dose and review patient history to avoid future complications.  5.Angina and Myocardial Infarction (Heart Attack) Causes: Underlying heart conditions, stress, or reaction to medications. Angina Symptoms: Chest pain or pressure, often relieved by rest; pain may radiate to the arm or jaw. Heart Attack Symptoms: Severe chest pain, shortness of breath, nausea, sweating, or dizziness. Immediate Action: Aspirin: Give 160-325 mg aspirin if not contraindicated and if the patient is conscious. Oxygen: Provide supplemental oxygen if available. Positioning: Seat the patient in a comfortable, upright position. Emergency Services: Call for medical help immediately. Follow-Up: Keep the patient calm, monitor their condition, and prepare for transport to the hospital.  6. Hypoglycemia (Low Blood Sugar) Symptoms: Shakiness, confusion, sweating, dizziness, or loss of consciousness. confusion, rapid heartbeat. Immediate Action: Oral Glucose: Administer a fast-acting glucose source, such as glucose tablets or fruit juice. glucose orally or via intravenous route if available Monitor: Check blood glucose levels if possible and observe patient response. Emergency Services: If the patient does not respond to oral glucose or loses consciousness, seek emergency help. Follow-Up: Ensure a full medical evaluation if hypoglycemia is recurrent.  7. Seizures Symptoms: Involves uncontrolled muscle activity (muscle contractions), loss of consciousness, and possible confusion afterward. Immediate Action: Safety: Move objects away from the patient and place a soft cushion under their head. Positioning: Turn the patient on their side to maintain a clear airway. Timing: Time the seizure. If it lasts longer than 5 minutes or if another seizure follows, seek medical help. Follow-Up: Monitor the patient after the seizure. If it’s their first seizure or if there are complications, refer for medical evaluation.  Protect the patient from injury and ensure their safety until the seizure subsides. 8. Respiratory Distress Difficulty breathing can be caused by various conditions. Symptoms: Difficulty breathing, shortness of breath, cyanosis bluish discoloration of the skin), or wheezing. o Difficulty breathing, shortness of breath, cyanosis. Immediate Action: Oxygen: Administer supplemental oxygen if available. Positioning: Sit the patient up to ease breathing. Monitoring: Continuously monitor vital signs and respiratory effort. Emergency Services: Call for emergency help if the condition worsens or does not improve. Follow-Up: Ensure a thorough medical evaluation to determine the cause of respiratory distress. 9.Asthma Attack Acute Asthma Attack in a Dental Setting Causes: Stress or exposure to allergens. Some common triggers that can cause asthma are: Colds, upper airway infections Pet dander Insect bites, stings Foods Pollen, paint and smoke First aid for a severe asthma attack 1. Perform a scene survey and a primary survey; send for medical help. 2. Place the casualty in the most comfortable position for breathing. This is usually sitting upright with arms resting on a table. 3. Help the casualty take prescribed medication. 4. Give ongoing casualty care. 5. If the unconscious casualty stops breathing, begin CPR. A person with asthma may carry medication in the form of a: Metered-dose inhaler (MDI) Turbuhaler Diskus® Follow-up: Ensure the patient has an up-to-date asthma action plan. Signs and symptoms of a severe asthmatic attack: Shortness of breath with obvious trouble breathing Coughing or wheezing Fast, shallow breathing Casualty sitting upright trying to breathe Bluish color in the face (cyanosis ) Anxiety, tightness in the chest Fast pulse rate, shock Restlessness at first, and then fatigue Usually the person can give themselves this medication without help. If the person needs help, a first aider can assist. An inhaler delivers a pre-measured amount of medication. Always read and follow the manufacturer’s instructions. To assist with a Metered Dose Inhaler The metered dose inhaler (or “puffer”) is the more common method of delivering medication for asthma. 1. Shake the container, then remove the cap. 2. Tell the casualty to breathe out completely, 3.Tell the casualty to breathe in slowly and deeply—as the casualty does, the MDI will be pressed to release the medication. The MDI can be in the mouth, or just in front of the mouth. 4.Tell the casualty to hold their breath for 10 seconds so the medication can spread out in the lungs. Then tell them to breathe normally, so the medication won’t be expelled. If more doses are needed, wait at least 30-60 seconds before repeating these steps. 10.Hyperventilation Hyperventilation and Its Link to Breathing Cessation Causes: Anxiety or panic attacks. Signs: Rapid breathing, dizziness, tingling, fainting. First Aid:Encourage slow, deep breaths. Instruct the patient to breathe into cupped hands. Reassure the patient to calm anxiety. Follow-up: Assess anxiety levels and provide stress management techniques. 11.Trauma to the Airway Trauma-Related Breathing Emergencies Causes: Procedural trauma leading to bleeding or swelling in the airway. Signs: Difficulty breathing, coughing blood, cyanosis. First Aid: Sit patient upright to keep airway open. Administer oxygen. Call emergency services immediately. 12.Pneumothorax (Collapsed Lung) o Cause: Air leaks into the space between the lung and chest wall, often caused by trauma (e.g., a broken rib). o Signs: Sudden chest pain and shortness of breath, reduced breath sounds on one side. o First Aid: Call for emergency help immediately. Keep the patient calm and in a comfortable position (usually sitting upright) to assist breathing. Basic Life Support (BLS) and Airway Management 1. CPR (Cardiopulmonary Resuscitation): o Chest Compressions: For adults, compress the chest at least 2 inches deep at a rate of 100-120 compressions per minute. o Rescue Breaths: Deliver two breaths after every 30 compressions, ensuring the airway is open. o Airway Management: If the airway is blocked (e.g., by the tongue or a foreign object), ensure proper head-tilt, chin-lift techniques to open the airway. 2. Use of an AED: o If the person’s heart has stopped beating (cardiac arrest), an automated external defibrillator (AED) can be used to shock the heart back into a normal rhythm while continuing chest compressions. Automated External Defibrillator (AED) CPR CPR Steps CPR is as easy as (C –A –B) Choking Baby The pregnant or obese victim. Chest thrust may be used as alternative to Heimlich maneuver when the victim is in the: a) Late stages of pregnancy b) Obese 1. Stand behind the victim with your arms directly under the victim’s ambits and encircle the victim’s chest. 2. Place the thumb side of one fist on the middle of the victim’s Sternum, (Taking care to avoid the xiphoid process). 3. Grasp your fist with your other hand and perform backward thrusts until the foreign body is going out, or the victim becomes unresponsive "Recovery Position" Unconscious individuals who are breathing and whose hearts are functioning should be placed in what is called the "Recovery Position". This position ensures that their airways remain open, preventing the tongue from rolling back towards the throat, and keeps the head and neck extended to allow for the airways to widen. This also allows vomit or any fluid in the patient's mouth to exit without obstruction. The patient's limbs also play a crucial role in this position, as they help keep them calm and provide comfort and safety.  When we do the recovery position? It is essential to place the patient in the "Recovery Position" if their breathing becomes heavy, noisy, or does not return to normal despite clearing the airways. The breathing and pulse are good but the patient is not conscious yet  Recovery Position 1. Position the arm closest to you at 90 degrees in front of the casualty, keeping it out of the way when rolling them. 2. Position the arm furthest from you on the casualty’s chest ,Bend the far knee. 3. Reach behind the casualty’s shoulder and roll casualty towards you by pulling on the far knee. 4. Adjust the position of the arms and leg so the casualty is in a stable position. Place the far arm at 90 degrees to the casualty with the palm down. 5. Give ongoing care. "Recovery Position"  Signs of as Asphyxia  Difficulty in breathing and signs of restlessness.  The rate of breathing increases.  The breaths get shorter.  The veins of the neck become swollen.  The face, lips, nails, fingers and toes turn blue: and the pulse gets faster and feebler.  Gas Inhalation Common symptoms of gas inhalation include: Difficulty breathing or shortness of breath Dizziness or confusion Nausea or vomiting Coughing or irritation of the throat and lungs Unconsciousness steps to follow for gas inhalation first aid 1.Ensure your safety first 2. Move the person to fresh air 3.Check for responsiveness 4. Check breathing and airway 5. Loosen tight clothing 6. Provide oxygen (if available) 7. Place in the recovery position (if unconscious but breathing) 8. Monitor symptoms 9. Seek medical attention 10. Be ready to provide CPR Respiratory System Pathologies Relevant to First Aid 1. Chronic Obstructive Pulmonary Disease (COPD): Patients may experience flare-ups, characterized by shortness of breath. First aid focuses on ensuring proper ventilation and helping patients use prescribed medications. 1. Pneumonia: An infection that inflames the air sacs in one or both lungs, potentially requiring oxygen support. Preparedness in the Dental Clinic Preparedness for No Breathing and Other Emergencies Have emergency equipment (oxygen, EpiPen, AED) readily available. Train all staff in Basic Life Support (BLS) and CPR. Perform emergency drills regularly. Assess patient medical history before procedures.