Respiratory System: Mechanics of Breathing

Respiratory Anatomy and Physiology

• To move air, the respiratory system alters pressure in the chest cavity.
• Air moves in with negative pressure and out with positive pressure.
• The respiratory system muscles contract and relax, generating changes in pressure.
• Inspiration is an active process, requiring muscle contraction to increase the chest cavity size.
• During inspiration, intercostal muscles and the diaphragm contract which lowers the diaphragm and moves the ribs upward and outward.
• During inspiration, air is pulled into the lungs.
• Expiration is a passive process where the rib muscles and diaphragm relax, reducing the chest cavity size and forcing the air out of the lungs.

Adequate Breathing

• Adequate breathing is sufficient to support life.
• Signs of adequate breathing include normal metal status with moving air when breathing, ability to speak relatively normally without having to catch their breath, and normal color and oxygen saturation typically in normal range
• For adults adequate breathing is 12 to 20 breaths/minute, school-age children 18 to 30 breaths/minute, and infants 30 to 60 breaths/minute
• Rhythm is usually regular and breath sounds are normally present and equal.

Inadequate Breathing

• Inadequate breathing is not sufficient to support life.
• Signs include a rate out of the normal range which can be too face or slowing and irregular
• Inability to speak and/or a silent chest can denote breathing difficulty.
• Low oxygen saturation despite supplemental oxygen can denote breathing difficulty.
• Agonal respirations and irregular rhythm can denote breathing difficulty
• Diminished or absent lung sounds and/or poor tidal volume can indicate breathing difficulty.

Pediatric Note

• The structure of the infant's and child's airway differs from that of an adult.
• Smaller airways are easily obstructed.
• Infants have proportionally larger tongues and a smaller, softer, more flexible trachea than adults.
• Infants have a less developed and less rigid cricoid cartilage
• Pediatric airways have heavy dependence on the diaphragm for respiration
• Signs of inadequate breathing in infants and children include nasal flaring, grunting, seesaw breathing, and retractions.

Patient Care for Inadequate Breathing

• Assisted ventilation with supplemental oxygen should be initiated.
• Pocket face mask with supplemental oxygen can be used.
• Two-rescuer bag-valve mask with supplemental oxygen can be used, as well as a One-rescuer bag-valve mask with supplemental oxygen can be used

Adequate Artificial Ventilation

• Chest rise and fall should be visible with each breath.
• Adequate artificial ventilation rates for adults is 10 to 12 breaths per minute.
• Adequate artificial ventilation rates for infants and children is 12 to 20 breaths per minute.
• Increasing pulse rates can indicate inadequate artificial ventilation in adults.
• Decreasing pulse rates can indicate inadequate artificial ventilation in pediatric patients.

Breathing Difficulty

• Patient's perception of breathing difficulty can depend on their subjective experience.
• It is a feeling of labored or difficult breathing
• The amount of distress felt may or may not reflect the actual severity of the persons condition.
• Key questions to ask a patient with breathing difficulties are: When did this start? What were you doing when this came on? Do you have a cough and are bring anything up with it? Do you have pain anywhere else in your body? Rate your breathing on a scale between 1 and 10. How long have you had this feeling?
• Things to observe are: altered mental status, unusual anatomy like barrel chest. the patients position such as tripod or sitting with feet dangling, any work of breathing
• Work of breaking observations include: Retractions, use of accessory muscles, Flared nostrils, Pursed lips, the amount of words a patient can say before needing to stop
• Skin condition: Pale, cyanotic (blueish), or flushed skin.
• Pedal and sacral edema should be noted
• Noisy breathing is important to observe; is there audible wheezing, gurgling, snoring, stridor or coughing?
• Stridor, or coughing, is a noisy breathing sound.
• Auscultate for: Lung sounds, wheezes, high-pitched sound in narrowed airway passages, crackles which are fine crackling or bubbling sounds on inspiration from fluid in alveoli, rhonchi which are lower pitch from secretions, evaluate changes in vital sings such as increased/decreased pulse rate, breathing rate, breathing rhythm, hypertension, hypotension
• When caring for a patient with breathing difficulties, assure adequate ventilation, provide artificial ventilation if inadequate, give non-rebreather mask of 15L/min or nasal canula of 6L/min. Place patient in comfortable position

CPAP - Continuous Positive Airway Pressure

• CPAP is form of noninvasive positive pressure ventilation through mask that blows oxygen to prevent alveoli from collapsing
• CPAP common uses include pulmonaty edema, drowning, asthma & COPD, respiratory failure
• CPAP contraindications include altered mental status, lack of spontaneous breathing, inability to sit up, hypotension, nausea, chest trauma, shock, GI bleeding, preventing good mask seal
• CPAP side effects include hypotension, pneumothorax, increased risk of aspiration and drying corneas
• Explain the procedure to patient. Start with flow level CPAP. Reassess mental status, level of dyspnea often, increase CPAP level after a few minutes. If patient deteriorates; use bag mask.

COPD - Chronic Obstructive Pulmonary Disease

• COPD is a broad classification of chronic lung disease that includes emphysema, chronic bronchitis and many respiratory illnesses.
• Chronic Bronchitis: Bronchiole linings are inflamed and excess mucus is produced.
• Cells in the bronchioles are normally clear away mucus accumulations are unable to do so.
• The over whelming majority of cases are caused by cigarette smoking.
• Emphysema: Alveoli walls break down causing reduced surface area and lungs lose elasticity
• Emphysema results in air laden with carbon dioxide being trapped in lungs causing ineffective breathing.

Asthma

• Asthma consists of chronic disease with episodic exacerbations.
• During an attack small bronchioles narrow caused by bronchoconstriction mucus is overproduced.
• Small airflow closing restricts air glow.
• Airflow mainly restricted in one direction.
• When asthma is triggered. the expanding pull of the lungs allows airflow into lungs. During exhalation air becomes trapped in lungs

Pulmonary Edema

• Pulmonary edema is the abnormal accumulation of fluid in alveoli, commonly affecting patients with CHF
• Pressure builds in pulmonary capillaries. Fluid crosses thin barriers and accumulates in alveoli.
• Fluid Occupying lower airways makes it difficult for oxygen to reach blood resulting in Dyspnea.
• Signs and Symptoms include: Dyspnea, anxiety, Pale/sweaty skin, tachycardia, hypertension, rapid labored respirations and low O2 Stats
• Severe causes gurgling without stethoscope. Crackles and wheezes may be audible. May cough up frothy sputum or pink tinged white sputum.
• Assess for and treat inadequate breathing, with high concentration O2, keep patients leg in dependent position and CPAP for capillaries.

Pneumonia

• Pneumonia is the infection of one or both lungs caused by bacteria, viruses, or fungi.
• Pneumonia results from Inhalation of certain microbes that grow in lungs and cause inflammation.
• Signs and symptoms include Shortness of breath, coughing, fever/severe chill, chest pain, headache, pale sweaty skin, fatigue, confusion.
• Treatment consist of supportive care. Assess and treat any breathing. hypoxia administer supplemental O2 and consider CPAP. Can require artificial respirations.

Spontaneous Pneumothorax

• Spontaneous Pneumothorax is when the lung collapses without an injury
• Risks include COPD, smoking or is tall and thin person Signs and symptoms of spontaneous Pneumothorax include chest pain, chest pains, shortness of breath, tiring easily, low O2 saturation and cyanosis, tachycardia
• Fast breathing, could hear decreased or absent lung sounds on injured lung, worsening, JVD and hypotension
• Treatment required contact ALS if pneumothorax is suspected, administer O2 with CPAP contraindicated for transport only. patient may require small catheter/larger chest Tube for care.

Pulmonary Embolism

• Pulmonary embolism is the Blockage in blood supply to lungs from deep vein thrombosis (DVT).
• Common reasons for DVT, laying or sitting in the same position for an extended period, active cancer or with and limb, immobilized in a cast
• Signs and symptoms include: Sharp pleuritic chest pain. SOB, anxiety, coughing, Tachycardia, tachypnea, lightheadedness, pain and swelling in only legs, hypotension and cardiac arrest
• Treatment consist of administer O2 and treat the shot and treat like any other patient with shortness of breath and transport

Epiglottitis

• Epiglottitis infection causing the swelling around and above the epiglottis
• Severe causes swell and can cause airway obstruction
• Signs and symptoms of Epiglottitis includes: Sore throat painful or difficult swallowing, tripod position sick appearance, mufffled voice, Fever, drooling and stridor
• Treatment consist of keeping patient calm and comfortable do not inspect throat. If possible and with high concentration of O2 without transporting.

Croup

• Croup viral illness, information of the larynx trachea and bronchi
• Tissues in the airway are swollen restricting passage of air
• Signs and symptoms of Croup includes: Loud barking cough, hoarse voice, Associated breathing difficulty typically results when moved in upright position, inadequate breathing, indicated by hypoxia and mental status includes signs of significant breathing such with stridor
• Treatment Involves if any signs adequate breathing in with initiate, artificial respirations, and transport immediately If patient is not in respiratory distress but is adequate. initiate gentle transport and called for and support. if the patient remains in a position of comfort and is high hypoxia offer supplemental O2.

Bronchiolitis

• Bronchiolitis, commonly associated with RSV, consists of swelling of small airways resulting from infection,
• Signs and symptoms of Bronchiolitis include other cold like symptoms, such runny nose, fever, illness symptoms, typically, progress over days and worsening and Common for multiple children in the house to be sick. can calls respiratory distress in breathing.
• Treatments involve if necessary providing artificial ventilation. with supplemental consider suctioning the nose if obstructed. Cleaning the noise for infants can help

Cystic Fibrosis

• Cystic Fibrosis consists of genetic disease, typically appearing in childhood
• Causing thick sticky mucus accumulating in the lines of digestive system
• Mucus can cause in serious and digestion -Problems
• Signs and symptoms of -Cystic Fibrosis includes coughing with large amounts of mucus, frequently or pneumonia in abdomen pain coughing, blood, nausea and weight loss patient a resource assessment of patient. and often to guide treatment

Viral Respiratory Infections

• Viral Respiratory Infections include Infection of the respiratory tract
• Viral Respiratory Infections are Common in more than 17 billion people each year.
• Signs and symptoms Viral Respiratory Infections consists start with sore or throat with sneezing. -Fever and chills. Infection in the lungs, causing shortness. produce.
• Treat viral infection. oxygen and bronchodilators.

Explore the mechanics of breathing, including inspiration and expiration. Learn about the roles of the diaphragm, intercostal muscles, and pressure gradients in moving air into and out of the lungs. Understand how observations like nasal flaring and intercostal retractions indicate respiratory distress.