Introduction Asthma is chronic inflammatory disease of the airways in the lungs which cause recurrent bronchial obstruction. Its symptoms demonstrate as shortness of breath, wheezing, cough, chest tightness as well as cyanosis. It is the most common chronic disease among children. This case is on a five-year-old girl called Jessica who was in emergency department for an asthma attack and was diagnosed with moderately severe asthma. The following essay will focus on Jessica’s case and explain the pathophysiology and pharmacology of asthma as well as her symptoms.
Pathophysiology Asthma develops from the interaction between genetic and environment factors and its triggers can be various from person to person. It is characterized by reversible airway obstruction which causes by airway inflammation. This inflammation brings about the functional changes of airways as bronchospasm, mucosal edema as well as mucus plugs narrowing the airways and blocking the oxygen supplies of a patient. Bronchoconstriction In respiratory system, molecules of oxygen get into the lungs by going through bronchi and bronchioles and later entering the alveoli where oxygen and carbon dioxide exchanging achieves.
These structures deliver fresh air to the air sacs and enable the oxygen passes through these air sacs and travels into the bloodstream. Red blood cells then transport the oxygen around the entire body to support its functioning. At the same time, carbon dioxide transfers from the bloodstream into the air sacs and gets breathed out of the body. During normal breathing, the smooth muscle bands surround the airway are relaxed. For patients with asthma, the smooth muscle is contracted which can spasms and squeezes the airway tighter causing bronchoconstriction.
Their respiratory system is affected as the bronchoconstriction resists the airflow and makes it harder to expel air. This constriction makes it impossible for the air in the alveoli to be discharged and the lungs become hyperinflation. In order to get rid of the blocked air, patients may try to cough to maintain breathing as Jessica had occasional coughing at night and developed into coughing continuously. Inflammation The pathophysiology of asthma is due to an inflammatory process with the participation of many cells and cellular including mast cell, eosinophil, lymphocytes and etc.
The inflammatory response in the airway of asthma patients is an abnormal immune response attributing to the interplay of genes and environment. In normal people’s airways without asthma, there is no mucus or swelling inside. In contrary, in the airway of the patient with asthma, there are excess mucus and thickened airway wall due to inflammation. Excess mucus, thickened airway wall together with bronchoconstriction contribute to the narrowing of airway of the lungs and cause respiratory failure.
This inflammatory response can lead to different extents of airway changes in asthma from acute, chronic to persistent inflammatory reactions. For acute asthma, the inflammation is usually reversible as the case of Jessica. Risk factors There are usually multiple triggers that contribute to the asthma attack for different people. In Jessica’s case, there are several risk factors. First of all, she was born at 33 weeks gestation. Premature birth is an affecting factor for children developing asthma. (1)Secondly, tobacco smoke increases the risk for asthma by inducing inflammation. 2)Second hand smoke can also trigger asthma. In Jessica’s family, she is exposed to her father and brother’s problematic alcohol and drug use and they may probably be smokers. Thirdly, as Jessica’s family keep two long-haired dogs and a short-hair cat, they may become the animal allergens for causing asthma. Fourthly, childhood asthma is also associated with emotional and physiological factor according to the research of Mary. (3)There are changings in Jessica’s family as her family has moved and her home life is unsettled. She started school in a new environment and she had learning difficulties.
Besides her grandmother’s health has been deteriorating. And there is violence within the family by her father and brother. These underlying stresses all play a role in developing asthma even though she may not notice at all. In addition, environmental factors as changing of temperature, humidity could also result in asthma. As Jessica has recent moved to a new place, the weather change may become one of the triggers. Last but not least, Jessica has the past medical history of eczema, study shows that children with eczema or ermatitis are more likely to develop asthma as they are more sensitive to common allergens. All these factors may work together and interact to trigger Jessica’s asthma attack. Symptoms and signs of Jessica Jessica showed the symptoms of a low grade fever and coughing at night in last two days and later developed into increasing shortness of breath and continuous coughing. On auscultation in emergency department, she had audible wheezing. Besides, her respiratory rate and pulse rate were both high and her Sa02 was low as 90%. Wheezing Wheezing is a whistling sound usually occurs during exhalation.
It is one of the most common symptoms of asthma. During Jessica’s asthma attack, her airways are narrowed because of bronchoconstriction, mucosal edema and mucus plugs. Air passes through narrowed and constricted part of the airways and the alternation of the airway between nearly closed and open causes oscillations of the airway wall and produces a continuous sound. Wheezing happens more often during exhalation because the airways normally narrow during this period of respiration. Coughing Jessica had an apparent symptoms of coughing.
Because of the bronchoconstriction and mucus. More and more air is trapped in the lungs and unable to be exhausted. Coughing is the body’s natural defense for Jessica to force the trapped air and out of the lungs. Besides coughing is usually accompanied by wheezing as coughing can be considered as a harsh way of exhalation. Other symptoms and linkage In addition to wheezing and coughing, Jessica also presented shortness of breath for the obstruction of the airway makes it difficult to breathe in and out and result in alveolar hypoventilation.
Less oxygen is passed into the blood makes the hemoglobin saturate with lower levels of oxygen. Thus her SaO2 is lower than normal. As a result, her heart pumped more quickly in an effort to get more oxygen which needed by the entire body. This lead to a rapid pulse. Cyanosis may also occurs for the lack of oxygen in hemoglobin which makes the skin turns a blue or purple color. Apart from the symptoms that Jessica had during the asthma attack, another symptoms for patients with asthma like chest tightness and cyanosis.
As there is a decreased pressure within the lungs for filling with blocked air, the patient feel it hard to inhale and exhale. The muscles around the lungs pressed against it which contributes to the feeling of chest tightness. Pharmacology The ED consultant prescribes inhaled Salbutamol, inhaled Ipratropium as well as PO Prednisolone to Jessica. As the symptoms of asthma result from a combination of inflammation and bronchoconstriction, the pharmacological treatment focuses on anti-inflammation by using glucocorticoids and bronchodilation by using ? 2 agonists.
Salbutamol Salbutamol helps to open up the airways and so relieves the symptoms of bronchospasm. Salbutamol is a short acting B2 adrenergic agonists. It takes effect by stimulating B2 adrenergic receptors associated with bronchioles. As a result the calcium levels within cells of smooth muscles are lowered. The smooth muscle then becomes relaxed and bronchodilation is thus achieved. It is given by an inhaler, so that the medication is delivered directly into the airways and lungs and its effect is apparent within minutes. It is absorbed from bronchi, metabolized in liver and excreted by kidneys.
What needs to be aware of is that Salbutamol can, however, causes tremor and palpitations by stimulating B2 receptors in heart so that the dose requires to be well controlled. Ipratropium Ipratropium is a muscarinic antagonist. It improves lung function by blocking muscarinic cholinergic receptors in the bronchi, thereby promotes bronchodilation. (p. 968) Ipratropium is a quaternary ammonium compound and the medication is not readily absorbed from the lungs. Hence, it is less effective than the B2 agonists in rapid relief and is only indicated for long-term maintenance.
At the same time, its adverse effects are minimal except for dry mouth and irritation of the pharynx. Since ipratropium and the B2 adrenergic agonists produce bronchodilation by different mechanisms, their beneficial effects are additive. Prednisolone Prednisolone belongs to synthetic glucocorticoid which can decrease edema in the airways. It acts to reduce the inflammatory response by preventing release of inflammatory mediators from mast cells. Prednisolone is taken orally so that the absorption is rapid and nearly complete.
It is distributed by bounding to plasma proteins metabolized in liver and excreted by kidney. The common adverse effects of Prednisolone include infections, hypertension, hypokalemia, hyperglycemia and diabetes, osteoporosis as well as growth retardation. It should be noticed that the medication needs to be ordered in decreasing dose before it is completely stopped and patients on this medication requires random check of blood sugar level. Conclusion Asthma is attributed to airway inflammation and triggered by interaction of genetic and environmental factors.
By analyzing Jessica’s case, it can be found out that in her asthma attack, the triggers are probably associated with complex family dynamics and domestic violence. She demonstrated symptoms of shortness of breath, coughing, wheezing which result from a combination of inflammation and bronchoconstriction. Her medications include Salbutamol, Ipratropium for bronchodilation and Prednisolone for suppressing inflammation. Having a clear comprehension on the pathophysiology, pharmacology of asthma as well as their linkage in Jessica’s symptoms benefits in the therapy of disease and nursing the patient.
