Chapter 16: Ready for Review
• Respiratory disease is one of the most common pathologic conditions, and, as a result,
respiratory distress is one of the most common reasons for EMS dispatches.
• Impaired ventilation may be caused by upper airway obstruction, lower airway obstructive
disease, chest wall impairment, or neuromuscular impairment.
• Respiratory failure, or hypoventilation, can occur from a multitude of pathologic conditions,
from injuries to the lungs, heart, and neurologic system to overdoses. Care includes
providing supplemental oxygen.
• In hyperventilation syndrome, ventilation is excessive. If it continues, the patient may
experience chest pain, carpopedal spasm, and alkalosis.
• The nasal hairs in the nares (nostrils) filter particulates from the air, which flows through
the nose and is warmed, humidified, and additionally filtered by the turbinates.
• The mouth and oropharynx are highly vascular structures covered by a mucous membrane.
The hypopharynx is the junction of the oropharynx and nasopharynx.
• The larynx and glottis are typically considered the dividing line between the upper airway
and the lower airway. The thyroid cartilage is the most obvious external landmark of the
larynx. The glottis and vocal cords are found in the middle of the thyroid cartilage.
• The cricoid cartilage can be palpated just below the thyroid cartilage in the neck. It forms a
complete ring and maintains the trachea in an open position. Applying cricoid pressure,
known as the Sellick maneuver, is no longer recommended.
• The small space between the thyroid and cricoid cartilages is the cricothyroid membrane.
Because it contains few blood vessels and is covered only by skin and minimal
subcutaneous tissue, it is a preferred area for inserting a large IV catheter or a small
breathing tube.
• The primary components of the respiratory system are like an inverted tree, with the trachea
representing the trunk and the alveoli resembling the leaves.
• The trachea bifurcates into the left and right mainstem bronchi of the lungs at a ridgelike
projection of tracheal cartilage called the carina.
• Cilia line the larger airways and help move foreign material out of the tracheobronchial tree.
If a patient is dehydrated or has taken medications that dry secretions (such as
antihistamines), the cilia will not be able to effectively move secretions. The same is true if
the patient is overhydrated.
• Pulmonary circulation begins at the right ventricle, where the pulmonary artery branches
into increasingly smaller vessels until it reaches the pulmonary capillary bed, which
surrounds the alveoli and terminal bronchioles. Gas exchange occurs at the interface of the
alveoli and the pulmonary capillaries.
• The interstitial space can fill with blood, pus, or air, causing pain, stiff lungs, and lung
collapse.
• The primary functions of the respiratory system are ventilation, perfusion, and diffusion.
• Mechanisms of respiratory control are neurologic, cardiovascular, muscular, and renal.
• Patients who have traumatic brain injuries may exhibit abnormal respiratory patterns,
including agonal gasps; apneustic and ataxic patterns; Biot, Cheyne-Stokes, and Kussmaul
respirations; and central neurogenic hyperventilation, bradypnea, hyperpnea, hypopnea, and
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
tachypnea.
The brain is sensitive to reduced levels of oxygen. It requires a regular supply of oxygen
and glucose to function but can store neither. An altered level of consciousness could
represent respiratory compromise.
Respiratory disease can cause impairment in ventilation, diffusion, perfusion, or
combination of the three.
Certain respiratory diseases have classic presentations that might help with the primary
assessment.
It is critical to evaluate how hard a patient is working to breathe. Patients in respiratory
distress may be able to compensate at first, but will eventually become sleepy, have a
decreased respiratory rate and depth, and then experience decompensation.
Assessing a patient’s position of comfort and level of difficulty speaking may help in
determining the patient’s degree of distress. A patient sitting in a Fowler’s position and
speaking only in two- or three-word statements, for example, is probably in considerable
distress.
Patients in respiratory distress tend to seek the tripod position. The condition of a patient in
respiratory distress who is willing to lie flat may be quickly deteriorating. Head bobbing is
also an ominous sign.
Other signs of life-threatening respiratory distress include bony retractions, soft tissue
retractions, nasal flaring, tracheal tugging, paradoxical respiratory movement, pulsus
paradoxus, pursed-lip breathing, and grunting.
Note any audible abnormal respiratory noises. Noisy breathing is obstructed breathing.
Snoring indicates partial obstruction of the upper airway by the tongue. Stridor indicates
narrowing of the upper airway, usually as a result of swelling (laryngeal edema).
Auscultate the lungs whenever possible. Adventitious breath sounds are the extra noises
audible during auscultation; they include wheezing and crackles.
Crackles are any discontinuous noises heard during auscultation of the lungs. They are
caused by the popping open of air spaces and are usually associated with increased fluid in
the lungs.
Wheezes are high-pitched, whistling sounds made by air being forced through narrowed
airways, which makes them vibrate. Wheezing may be diffuse in conditions such as asthma
and congestive heart failure or localized when caused by a foreign body obstructing a
bronchus.
Silence means danger! If breath sounds are inaudible with a stethoscope, the patient is not
moving enough air to ventilate the lungs.
The respiratory system delivers oxygen to the body and removes the primary waste product
of metabolism, carbon dioxide. If the lungs are not functioning properly, both of these vital
functions may be impaired. Hypoxia, cell death, and acidosis can then occur.
Patients with dyspnea are usually transported to the nearest facility.
Patients who have chronic respiratory disease are often knowledgeable about their disease
and may have tried several treatment options already. Ask them about these efforts and
what results, if any, they produced.
Onset and duration of distress are important considerations in determining the underlying
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
cause. Find out if the problem happened suddenly or gradually worsened over time.
Find out if the patient’s condition is a recurrence of a past condition. If so, compare the
current situation with other episodes.
A patient who has respiratory disease may not be able to talk because he or she is having
difficulty breathing. The history may have to be obtained from a family member or from
only a few clues.
Assess the patient’s mucous membranes for cyanosis (a bluish or dusky color), pallor, and
moisture.
Assessing the level of consciousness is extremely important in dyspneic patients.
Look for jugular venous distention in the neck, with the patient in a semisitting position.
Distended neck veins may be caused by cardiac failure.
Feel the chest for vibrations as the patient breathes. Check for edema of the ankles and
lower back. Check for peripheral cyanosis. Check the pulse, and note the patient’s skin
temperature. Apply any available monitors.
A pulse oximeter indicates the percentage of the patient’s hemoglobin that has oxygen
attached. An oxygen saturation level greater than 95% is considered normal.
Exhaled carbon dioxide can be monitored with colorimetric end-tidal carbon dioxide
devices or with wave capnography.
The peak flow is the maximum flow rate at which the patient can expel air from the lungs.
Normal peak flow ranges from about 350 to 700 L/min. A peak flow of less than 150 L/min
is insufficient and signals that the patient is in significant respiratory distress.
Metered-dose inhalers deliver bronchodilators and corticosteroids as an aerosol treatment.
Dry powder inhalers deliver a measured dose of medication in the form of a fine powder.
Little or no medication may reach the lungs if improper technique is used.
Aerosol nebulizers deliver liquid medications in the form of a fine mist to the respiratory
tract. Weigh the potential benefits of aerosol therapy against the lower fraction of inspired
oxygen delivered during the treatment.
Emergency medical care for patients with dyspnea may include securing the airway;
decreasing the work of breathing; administering supplemental oxygen, bronchodilators,
leukotriene modifiers, methylxanthines, electrolytes, inhaled corticosteroids, vasodilators,
or diuretics; supporting or assisting ventilation; intubating the patient; injecting a betaadrenergic receptor agonist subcutaneously; and/or instilling medication directly through an
endotracheal tube.
In managing the condition of a patient who is in respiratory distress, begin by ensuring that
there is an open and maintainable airway. Suction if necessary, and keep the airway
optimally positioned. Remove constricting clothing. Reduce the patient’s effort to breathe.
Drug administration methods that require the patient to inhale the medication may become
unreliable or ineffective when the patient’s airways are severely compromised. Some cases
may warrant administering medications subcutaneously.
Medications can be instilled directly into the tracheobronchial tree when patients are
intubated or have a tracheostomy. Stop CPR compressions for a moment while instilling the
medication.
Continuous positive airway pressure (CPAP) is used as therapy for respiratory failure.
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Within several minutes of application, the patient’s oxygen saturation should increase, and
the respiratory rate should decrease.
Bilevel positive airway pressure (BiPAP) is CPAP that delivers one pressure during
inspiration and a different pressure during exhalation. It is more like normal breathing and
is often more comfortable for patients.
Automated transport ventilators are essentially flow-restricted oxygen-powered breathing
devices with timers. They are particularly good choices for filling the role of the bag-mask
ventilator when the patient is in cardiac or respiratory arrest but are not intended to ventilate
patients without direct observation and attention from a skilled practitioner.
Patients in respiratory failure may ultimately need to be intubated. There are major
drawbacks and risks to intubating in the field, but it can also be lifesaving. Weigh these
issues along with protocols, medical direction, and the patient’s wishes.
Anatomic or foreign body obstructions of the upper airway, including aspiration of stomach
contents, can cause seizures and death. Avoid causing gastric distention when administering
bag-mask ventilation, and monitor the patient’s ability to protect his or her airway. If the
patient cannot protect his or her airway, the patient must be intubated.
Infections can cause swelling in the upper airway. Croup is one of the most common
conditions causing airway swelling, although it usually occurs only in small children.
Common obstructive airway diseases include emphysema, chronic bronchitis, and asthma.
Emphysema and chronic bronchitis are collectively classified as COPD.
Asthma is caused by allergens or irritants and is characterized by widespread, reversible
narrowing of the airways (bronchospasm), edema of the airways, and increased mucus
production. It can cause significant airway obstruction.
Primary treatment of bronchospasm is bronchodilator medication. Primary treatment of
bronchial edema is corticosteroids, which may or may not be administered in the field
setting.
Status asthmaticus is a severe, prolonged asthmatic attack that cannot be stopped with
conventional treatment. It is a dire medical emergency. Any person with asthma who feels
sick enough to call an ambulance is in status asthmaticus until proved otherwise.
When a patient has recurring asthma attacks, his or her inhaler could be empty or the
medication could no longer be effective. Try administering a new bronchodilator.
Noncompliance with the prescribed medication regimen could trigger an asthma attack. Ask
what the patient was doing when the asthma attack began. Ask if the patient took his or her
medications today. Ask if movement worsens the dyspnea.
Emphysema is a chronic weakening and destruction of the walls of the terminal bronchioles
and alveoli. A patient with emphysema classically has a barrel chest, muscle wasting, and
pursed-lip breathing. Tachypnea is often present.
Chronic bronchitis is characterized by excessive mucus production in the bronchial tree,
nearly always accompanied by a chronic or recurrent productive cough. A patient with
chronic bronchitis tends to be sedentary and obese, sleep in an upright position, use many
tissues, have copious secretions, and be cyanotic.
In assessing patients who have COPD, search for the cause of a worsened condition that
prompted the call for help. Look for signs of infection, peripheral edema, jugular venous
•
•
•
•
•
•
•
•
•
•
•
•
•
distention with hepatojugular reflux, and crackles. Find out if the onset of dyspnea was
sudden or gradual.
Hypoxic drive is a phenomenon in which high levels of oxygen decrease the patient’s
respiratory drive. Nevertheless, supplemental oxygen should not be withheld.
Not every patient should be ventilated the same way. Allow the patient to exhale
completely before the next breath is delivered. If the patient is not allowed to do so,
pressure in the thorax will rise, eventually causing pneumothorax or cardiac arrest. This
phenomenon is called auto-PEEP. If auto-PEEP is a risk, ventilation should be at a rate of 4
to 6 breaths/min. The standard ventilation rate for adults without COPD is 8 to 10
breaths/min.
Pneumonia may be caused by a variety of bacterial, viral, and fungal agents. A patient with
pneumonia usually reports weakness, productive cough, fever, and sometimes chest pain
that worsens with coughing. Supportive care includes oxygenation, suctioning, and
transport to an appropriate facility.
Atelectasis is alveolar collapse as a result of proximal airway obstruction, pneumothorax,
hemothorax, toxic inhalation, or other causes. Incentive spirometry can help prevent
atelectasis in postsurgical patients and others.
Lung cancer is often characterized by hemoptysis and is increasing among women.
Damage caused by inhalation of a toxic gas depends on the water solubility of the gas.
Pulmonary edema occurs when fluid migrates into the lungs. A patient expectorating foamy
pink secretions probably has severe pulmonary edema.
Acute respiratory distress syndrome is caused by diffuse alveolar damage as a result of
aspiration, pulmonary edema, or some other alveolar insult.
When a patient has a pneumothorax, air collects between the visceral pleura and the parietal
pleura. Administer supplemental oxygen, and monitor the patient’s respiratory status
closely.
Pleural effusion will cause dyspnea. Supportive care, including proper positioning and
aggressive oxygen administration, should be given.
A pulmonary embolism occurs when a blood clot breaks off in the circulation and travels to
the lungs, blocking blood flow and nutrient exchange. Bedridden patients and people with
thrombophlebitis are at risk of pulmonary embolism. The hallmark of a pulmonary embolus
is cyanosis that does not resolve with oxygen therapy.
Infants are less able than older children to compensate for respiratory insults.
Infants and children with respiratory problems may be in respiratory distress (difficulty
breathing), respiratory failure (a condition that invariably leads to decompensation), or
respiratory arrest. It is important to resuscitate a child before cardiac arrest occurs.