Case Study Answers and Summary
1. What initial management is indicated for this child?
• 100% supplemental oxygen (via pediatric nonrebreathing mask)
- Though clearly experiencing respiratory distress, this patient’s respiratory effort is producing adequate air movement. Therefore, positive-pressure ventilation support is not needed at this time.
You must carefully monitor the child with respiratory distress and be prepared to provide positive-pressure ventilations if signs of respiratory failure develop. Signs of respiratory failure include, among others, reduced tidal volume and poor air movement, decreased level of consciousness, a low (> 90%) or rapidly falling oxygen saturation, and signs of physical exhaustion.
Failure of the respiratory system is the most common cause of cardiac arrest in the pediatric population. However, with frequent respiratory system assessments and prompt management, this potential catastrophe can often be prevented.
2. What is your field impression of this child?
You should suspect that this child is experiencing an acute asthma attack. In addition to the complaint of difficulty breathing, the following pertinent findings support this field impression:
• Expiratory wheezing, which is a hallmark sign of a mild to moderate asthma attack. Expiratory wheezing indicates impaired airflow during expiration and is indicative of bronchospasm.
- By no means is wheezing exclusive to asthma. Other conditions, such as pneumonia and toxic inhalations, cause wheezing as well. However, the clinical scenario involving this patient does not indicate a toxic exposure and the fact that she is afebrile (97.8°F) is not consistent with pneumonia or other infectious causes of respiratory distress.
• Cold air exposure, which is a common precipitant to an asthma attack. Like any other smooth muscle, the smooth muscle surrounding the bronchiole constricts when exposed to cold air.
• Prescribed medications, which indicate the presence of an episodic disease that requires periodic treatment. Other respiratory illnesses, such as croup, bronchitis, and pneumonia, are typically treated with a trial of medications, and usually resolve without the need for ongoing treatment.
• The nature of onset, which, in this patient, was coughing. As the bronchioles become irritated, the patient often begins to cough, sometimes violently. Then, as bronchospasm progresses, respiratory distress develops.
Asthma is the most common chronic childhood disease, affecting approximately 5 million American children over 1 year of age. Nearly half of all pediatric asthma deaths occur in the prehospital setting.
Asthma is a chronic but reversible condition, characterized by bronchospasm, mucous plugging, and edema in the lower airways. Asthma is commonly referred to as reactive airway disease (RAD) — a nonspecific condition in which intrinsic or extrinsic factors cause bronchospasm — at least initially, until a physician determines that the patient has met all of the diagnostic criteria for asthma.
An acute asthma attack is commonly precipitated by factors such as an allergen exposure, stress, exercise, recent upper respiratory infections, and exposure to cold air or passive cigarette smoke. In response to the precipitating event, a series of reactions occur in the lower airway. First, the smooth muscle surrounding the bronchiole begins to spasm, resulting in bronchoconstriction. Secondly, mucous glands and cells that line the lower airway secrete excessive mucous, which accumulates in the bronchioles, creating a plug. Finally, fluid shifts into the walls of the lower airway, resulting in edema that further decreases the diameter of the bronchiole. The net result is a narrowing of the small airways with increased resistance to airflow.
These three factors — bronchospasm, mucous plugging, and airway edema — result in a ventilation-perfusion mismatch. In other words, the pathophysiologic changes associated with asthma cause some alveoli to become hyperinflated due to air trapping, while other alveoli collapse (atelectasis). Hypoxemia develops because the collapsed alveoli are still being perfused, but are unable to participate in gas exchange. Therefore, the blood flowing through the capillaries adjacent to the collapsed alveoli returns to the left side of the heart, still unoxygenated. This condition is referred to as intrapulmonary shunting.
In between attacks, the child with asthma is typically asymptomatic. However, during an acute attack, varying degrees of difficulty breathing, tachypnea, tachycardia, and wheezing are present.
As a baseline, an acute asthma attack presents with some degree of respiratory distress. The presence of wheezing often characterizes the severity of the attack, and thus, the degree of bronchoconstriction. In a mild to moderate asthma attack, wheezing is typically audible at the end of expiration, indicating increased resistance to expiratory airflow. Oxygen saturation levels may be normal or slightly low.
During a more severe asthma attack, wheezing may be audible during inspiration and expiration. Oxygen saturation levels typically reflect mild hypoxemia, with readings that usually range from 91% to 94%.
Status asthmaticus, the most severe exacerbation of asthma, is a life-threatening condition that often requires multiple modalities of frequent or continuous treatment to improve. The child with status asthmaticus presents with air hunger (struggling to breathe). However, because of the profound bronchoconstriction and minimal airflow through the bronchioles, wheezing is either faint or completely absent. Oxygen saturation levels often reflect severe hypoxia, with readings well below 90%. As hypoxemia worsens, hypercarbia (increased arterial CO2 levels) develops and the child may become unresponsive.
3. Are the child’s vital signs and SAMPLE history consistent with your field impression?
According to the following formula, this child’s blood pressure of 96/56 mm Hg is consistent with her age:
• Age [in years] 3 2 1 70 5 systolic blood pressure
Her heart rate and respiratory rate, however, indicate respiratory distress. Additionally, her oxygen saturation of 93% indicates mild hypoxemia.
Although she cannot remember the name of her medication, the fact that she has prescribed medications is an indicator of an episodic disease that requires periodic treatment, such as asthma. Additionally, she has confirmed that her doctor told her that she has a “breathing problem.”
As previously discussed, her episode of coughing prior to developing respiratory distress is a fairly common finding in patients with asthma.
Back to Pediatric Case Study for Paramedics: 7-Year-Old Female with Difficulty Breathing
