This section of our NREMT Study Guide will focus on preparing you for the respiration portion of the exam. Here, we will cover factors affecting respiration, the many different types of respiratory illnesses and diseases, the signs and symptoms of each, and how to treat each respiratory emergency following your EMT training and local protocols.
Once you have gone through this section of the study guide, you can take a quiz consisting of five practice questions to assess your understanding of the material covered.
Factors Affecting Respiration
For adequate respiration to occur, proper oxygenation and ventilation must occur. External factors that affect respiration include atmospheric pressure and the partial pressure of oxygen in the ambient air. The percent of oxygen remains the same at high altitudes; however, the partial pressure of oxygen decreases due to the decrease in atmospheric pressure.
When the partial pressure of oxygen is low, it can be difficult or impossible to oxygenate tissue satisfactorily, resulting in an interruption of internal respiration. Another factor that makes adequate oxygenation and respiration difficult is exposure to carbon monoxide and other poisonous gases. Carbon monoxide has 250 times more of a chance of binding to the hemoglobin in the blood than oxygen, prohibiting oxygen delivery to the tissues. If left untreated, severe hypoxemia and death will occur.
Internal factors that affect respiration include pulmonary edema, pneumonia, COPD, and other infections. When a patient has either of these medical conditions, the surface area for gas exchange is reduced. When the surface area is reduced, the oxygen supply to the body decreases, leading to poor tissue perfusion.
These medical conditions also damage the alveoli, causing fluid to accumulate in the lungs. When the alveoli are not functioning correctly, diffusion of oxygen and carbon dioxide is inhibited.
Respiratory Emergencies
EMS is often called for patients experiencing dyspnea (difficulty breathing) or shortness of breath (SOB). This can be due to a foreign body airway obstruction, respiratory illness or disease, or an injury. When assessing a patient with difficulty breathing, it may be challenging to understand exactly what is happening from a physiological standpoint. However, as an EMT, you are trained to assess and treat the patient according to their signs and symptoms, your training, and local protocols. This section covers the most common respiratory emergencies and how to treat patients with dyspnea.
Foreign Body Airway Obstruction (FBAO)
The most common airway obstruction in unconscious patients is the tongue. As it relaxes into the back of the throat, it partially or completely blocks the airway. Using the head tilt-chin lift or jaw-thrust maneuver generally corrects this problem.
Other foreign body airway obstructions occur when a patient is eating or a child places an object into their mouth. It is essential to recognize if the obstruction is mild or severe. Mild airway obstructions will allow the patient to exchange air with varying degrees of respiratory distress. The goal is to prevent the mild airway obstruction from becoming a severe obstruction.
With a mild airway obstruction, assess the patient to determine if they have good or poor air exchange. When the patient has good air exchange, they may have wheezes and be coughing forcefully. Wheezes indicate a mild lower airway obstruction and are heard during respiration. Encourage the patient to continue coughing forcefully to expel the object on their own. No further interventions are needed by you, but continue closely monitoring the patient in case their airway becomes completely blocked.
When patients have poor air exchange, they will have a weak cough (not forceful), increased dyspnea, stridor, and cyanosis. Stridor is a high-pitched sound heard primarily on inspiration, indicating a mild upper airway obstruction requiring immediate care. Any patient with a mild airway obstruction with poor air exchange needs to be treated as if they have severe airway obstruction.
Patients with a severe airway obstruction cannot cough, breathe, or talk. The patient may clutch or grasp their throat (the universal sign for choking), turn cyanotic, have severe dyspnea, and/or make absent breath sounds. Ask the conscious patient if they are choking and provide immediate treatment if they nod their head “yes.” If the obstruction is not quickly cleared, the patient will become hypoxic and unconscious and can die.
Airway obstruction can also occur that does not include a foreign body, such as swelling and inflammation of the airways from infection, acute allergic reactions, or trauma. These patients require advanced medical care for the obstruction. They need rapid transport to the hospital or ALS assistance, depending on your local protocols.
Common Respiratory Diseases and Illnesses
These are the most common respiratory diseases and illnesses seen in the field, including associated signs and symptoms:
- Asthma–wheezing, severe respiratory distress, mouth breathing, anxiety
- Chronic obstructive pulmonary disease (COPD)–dyspnea, sputum production, chronic cough, long expiration phases, wheezing
- Pneumonia–fever, chills, productive cough, clammy skin, shortness of breath
- Congestive heart failure (CHF)–dyspnea (especially when lying down or upon exertion), wet lung sounds, edema, productive or non-productive cough with pink, frothy sputum
- Croup–fever, labored breathing, wheezing, seal-like barking cough
- Epiglottitis–shortness of breath, noisy breathing, drooling, fever, difficulty swallowing
- Pulmonary embolism (PE)–fast breathing or SOB, dry cough, chest pain
- Anaphylaxis–difficulty breathing, wheezing, hives, anxiety, poor skin signs, shock
- Hyperventilation syndrome–dizziness, anxiety, muscle spasms in hands and feet, rapid and shallow breathing, chest pain
While many of these diseases and illnesses will present the same, the signs and symptoms may vary. Review the signs and symptoms of each respiratory illness/disease, as there are more than what is listed, the vital signs associated with each (including breath sounds), and the treatment based on local protocols.
While you are not taught to “diagnose,” you are taught to form a general impression of the patient. Therefore, you should know the difference between the signs and symptoms of COPD vs. CHF, for example, as that question may be asked on the test.
Treatment
While the treatment for respiratory emergencies varies by protocol, the general treatment that EMTs are taught remains the same. Depending on the patient’s oxygen saturation and level of respiratory distress, you are taught to apply either low or high-flow oxygen by nasal cannula or nonrebreather mask, keep the patient calm, and transport in the position of comfort, which is normally in a seated or upright position. If local protocols allow, you may be able to assist the patient with administering a breathing treatment or metered-dose inhaler (MDI).
Patients diagnosed with respiratory illnesses will often be prescribed a metered-dose inhaler, which is a small spray canister filled with medication that the patient sprays through their mouth and into the lungs.
MDIs are typically prescribed to patients diagnosed with asthma. The most common inhalers are beta-agonists that dilate the breathing passages, such as albuterol (Ventolin, Proventil), metaproterenol (Alupent, Metaprel), and terbutaline (Brethine). This type of medicine is a bronchodilator that opens the airways by relaxing the muscles around them.
The dose given with an MDI is one puff initially. The patient should be encouraged to take a few breaths. If the patient continues to have dyspnea, a second dose can be repeated per local protocol or medical direction.
Small-volume nebulizers are also prescribed to patients with respiratory issues, such as asthma, COPD, anaphylaxis, and bronchiolitis. Like the metered-dose inhaler, the nebulizer delivers medication through the patient’s mouth and into their airways. However, instead of a small canister containing the medication, the medication is added to a hand-held nebulizer and hooked up to oxygen, delivering a fine mist of aerosolized medication. The dose for small-volume nebulizers is continued until all of the medication has been administered or the patient is no longer in respiratory distress.
Small-volume nebulizers work quickly if the patient breathes the medicine correctly. The aerosolized medicine goes directly into the patient’s lungs, whereas the metered-dose inhaler does not travel as deep into the lungs. However, both are effective tools for patients in respiratory distress.
Indications and Contraindications
The indications and contraindications when assisting patients with MDIs and small-volume nebulizers are the same. You want to be sure the medication is indicated by the patient showing signs and symptoms of dyspnea. Patients with asthma will generally have MDIs or nebulizers, while patients with COPD, bronchiolitis, and anaphylaxis will have nebulizers.
These are the contraindications for assisting a patient with their MDI or nebulizer:
- The patient is unable to follow commands to coordinate the inhalation of the medicine
- The nebulizer or MDI is not prescribed to the patient
- The medication is expired
- You did not receive permission from medical control, or it is not permissible by local protocol
- There are other contraindications specific to the medication
- The patient has already administered the maximum dosage before your arrival
Some common side effects you will see after patients use an inhaler or nebulizer include an increased pulse rate, muscle tremors, nervousness, and coughing.
If the patient is unable to breathe effectively on their own after your interventions, you will be required to assist with ventilation, which will be covered in Section 1, Part 3: Ventilation.