Understanding Asthma Pathophysiology And Nursing Interventions Is Crucial For Effective Care.

Jackson Smith, a 18 year-old male, was admitted to the Emergency Department at 9pm with severe breathless-ness. His family informed you that the patient has a history of Asthma that had been diagnosed when he was two years old. On admission to the Emergency Department the clinical manifestations were: 

1. Explain the pathogenesis causing the clinical manifestations with which Jackson Smith presented with. 
2. Discuss two high priority nursing strategies to manage Jackson and provide evidence-based rationales for these strate-gies. 
3. Three of the drugs that were given to Jackson were continuous nebulised Salbutamol and nebulised Ipratropium bromide (4/24) and IV Hydrocortisone 100mg (6/24).

a. Discuss the mechanism of action of these drugs, and relate to the underlying pathogenesis of an Acute Severe Asthma. And,

b. Describe the nursing implications (monitoring for and responding to adverse effects, and evaluating therapeutic effect) when administering these drugs to a patient with an Acute Severe Asthma. 

CD4+ T-lymphocytes and Th2 cells in inflammation and airway obstruction

1. Asthma is a chronic lung disease which has no cure but can be effectively controlled (National Asthma Council Australia, 2017). According to Christensen, Craft, Wirihana and Gordon (2015), the main pathophysiology underlying asthma include inflammation in the airway causing hyper-responsiveness and mucus hyper secretion which results in the obstruction in the airflow. This obstruction in the airflow is the reason underlying the dyspnoea as experienced by Jason Smith who was suffering from acute severe asthma.  Other symptoms of blockage in the airway occurring include cough, tightness in chest and wheeze. These additional symptoms also coincide with the clinical manifestations of Jackson Smith at the time of Emergency Department: diminished sound of breath and widespread wheeze. It is due to tightness in chest that Jackson Smith was experiencing severe breathlessness along with high respiratory rate (32 beats per minute with normal rate of 20 beats per minute).

Asthma is associated with other immunological processed like increase in the concentration of CD4+ T lymphocytes along with increase in the secretion of the type 2 t helper (Th) cells along with cytokine mediators like IL4, IL5 and IL13. All these cytokine mediators are type hypersensitivity mediators, which causes inflammation and obstruction in the airway (Graziottin & Serafini, 2016). The activation of the type 1 hypersensitivity reactions leads to degranulation of the mast cells along with the release of the type 1 hypersensitivity mediators like histamine, interleukins, leukotriene, prostaglandins and nitric oxide. All these type 1 hypersensitivity mediators have vasoactive effects, which causes vasodilation along with increase in the capillary permeability. Increase in capillary permeability increases the blood flow in the lings along with increase in the infiltration of the inflammatory cells and chemotactic factors along with neutrophils, eosinophil and lymphocytes. This increase in the flow of the blood is the reason underlying the increase in the blood pressure (150/85 mmHg) and pulse rate (130 beats per minute) for 18-year old Jackson Smith (Graziottin & Serafini, 2016).

In addition to there is alteration of the normal autonomic control of the bronchial smooth muscle cells due to the production of neuropeptides (small protein-like substances which are released from the neurons in order to communicate with other neurons). The release of the neuropeptides causes increase in the release of the neurotransmitter, acetylcholine. The release of acetylcholine causes bronchospasm. Bronchospasm causes long-term damage in the airway. It is due to bronchospasm that Jackson Smith is experiencing laboured breathing or shortness in breath (Graziottin & Serafini, 2016).

Vasoactive effects of type 1 hypersensitivity mediators

Ostrom et al. (2013) highlighted that permanent damage cause by bronchospasm leads to recurrent asthmatic attack as in case of Jackson who is suffering from asthma from a tender age, 2 years. Increase in bronchospasm leads to bronchoconstriction. The increase in the inflammatory mediators like IgE further increases the severity of bronchoconstriction and leads to obstruction in the airways leads to wheezing sound of breath at the time of airflow. Bronchoconstriction can also be defined as additional reason behind the increase in the chest tightness of Jackson Smith. Ostrom et al. (2013) stated that wheezing is a type of musical sound that is generated because of limited flow of the air into the lungs or the pulmonary cavity.

The permanent change in the pulmonary airways caused through bronchoconstriction is defined as airway remodelling. This leads to progressive loss of the smooth muscle function in the lungs which is irreversible. Moreover, the oxygen saturation of Jackson Smith was found to be marginally low, 90 SpO2 on room air (normal 95 to 98 SpO2). This low oxygen saturation level leads to the generation asthmatic attack. Low level of oxygen saturation is defined as a process of low amount of oxygen dissolved in blood. This low amount of dissolved oxygen causes acute dyspnoea as per the condition of Jackson Smith and causes asthmatic manifestation (Darlow et al., 2014). The intensity of dyspnoea however varies with severity of asthma depending of several factors like bronchoconstriction, respiratory drive, dynamic hyperinflation and other associated physiological factors. Hyperinflation is the reason underlying the hyper-inflated lungs in the chest x-ray of Jackson Smith (Darlow et al., 2014).

As per the case study, the X-ray report of Jackson has highlighted hyper-inflated lungs. It is important to clear his hyper-inflated lungs in order ensure normal respiratory rate. Nursing interventions in order to clear airways of Jackson can be done through cough enhancement. This is because, coughing is considered as natural means of mucus or sputum clearance from the airways and throat. Proper arrangement of the sitting position with head slightly flexed along with shoulder relaxation and knee flexed with promotes coughing (Peytremann Bridevaux et al., 2015).

According to Fekr, Janidarmian, Radecka and Zilic (2015), the rational against this, lying flat causes the organs of the abdomen to move towards the diaphragm and making it difficult to breathe and thus promoting coughing. Clearance of mucus lungs will help to reduce the inflation of the lungs. This will also help to clear his airways and thus helping to decrease the wheezing breath and respiratory rate (Fekr, Janidarmian, Radecka & Zilic, 2015).

Permanent changes in pulmonary airways caused through bronchoconstriction

In case of Jackson, the level of oxygen saturation is SpO2 90%, thus it is at the margin.  Thus application of oxygen therapy might not be helpful. According to de Araujo et al. (2015) effective oxygen therapy is helpful in improving oxygen saturation which is less than SpO2 90%. The best suited therapy for Jackson is assessment of the exacerbation by monitoring the peak expiratory flow rates and forced respiratory volume under the assistance of respiratory therapist. Helping Jackson to perform pursed lip breathing will help to increase oxygen saturation. Increase in the level of oxygen saturation in the body will help Jackson to recover from shortness in breath. Increase in the level of oxygen saturation will also reduce the high blood pressure and high pulse rate. If the oxygen saturation falls below SpO2 90% then supply of external oxygen can be done with the help of Venturi mask or Hudson mask (de Araujo et al., 2015). According to Maggiore et al. (2014), the minimal flow of the oxygen requirement should be measured from entrained room air added with the fresh oxygen flow and this is equal to four to three times per minute of ventilation. This negligible flow of oxygen is required to satisfy patient’s peal inspiratory flow demands.

3a. Nebulised Salbutanol: Goodacre et al. (2013) stated that it works on beta 2 adrenergic receptors located in the smooth muscle cells of the bronchiole and this increase the secretion of cyclic-CAMP. Secretion of cyclic-AMP activated intracellular biochemical cascaded, which increase the influx of calcium inions and thus preventing contraction of smooth muscles and helping to relieve shortness of breath.

Nebulised Ipratropium: It is an anticholinergic agent which blocks muscarinic receptors of acetylcholine in the vagus nerves. This inhibits the cholinergic nerves and thus inhibiting smooth muscle contraction in the lungs (Koninckx, Buysse & de Hoog, 2013).

Hydrocortisone: Shan et al. (2013) stated that this medication inhibits the release of primary mediators of hypersensitivity by the phagocytic cell, macrophage. This is restricts the secretion of mucus in the airways and thereby preventing inflation of lungs and delaying the chemo-taxis of the inflammatory mediators.

3b. Careful surveillance of arterial blood gases and assessment of the vital signs is important during and after the administration of salbutamol. Proper monitoring of the cardiac dysrhythmias and tachycardia should be done along with the proper assessment of the past history of hypersensitivity (Lumb, 2016).

During the administration of ipratropium, it is important to adjust the dosage as per the body mass index of the patient. Proper assessment of the signs and the symptoms of tremors, dizziness and shaking must be done before and after the application of medicine (Koninckx, Buysse & de Hoog, 2013).

Various medications used to treat asthma

At the time of administration of hydrocortisone, it is important for a nursing professional to monitor the vital sign of the patients. Effective monitoring of vital signs will promote the dosage and the duration of the medication. Proper dosage management is important as long-term side-effects of hydrocortisone can cause peptic ulcer and hypertension (Shan et al., 2013).

References:

Christensen, M., Craft, J. A., Wirihana, L., & Gordon, C. J. (2015). Pathophysiology team teaching: bioscientist contribution to knowledge integration in a nursing subject. Journal of clinical nursing, 24(23-24), 3739-3741. https://doi.org/10.1111/jocn.12959

Darlow, B. A., Marschner, S. L., Donoghoe, M., Battin, M. R., Broadbent, R. S., Elder, M. J., ... & McNeill, N. J. (2014). Randomized controlled trial of oxygen saturation targets in very preterm infants: two year outcomes. The Journal of pediatrics, 165(1), 30-35. https://doi.org/10.1016/j.jpeds.2014.01.017

de Araujo, C. L. P., Karloh, M., Reis, C. M. D., Palú, M., & Mayer, A. F. (2015). Pursed-lips breathing reduces dynamic hyperinflation induced by activities of daily living test in patients with chronic obstructive pulmonary disease: A randomized cross-over study. Journal of rehabilitation medicine, 47(10), 957-962. DOI: https://doi.org/10.2340/16501977-2008

Fekr, A. R., Janidarmian, M., Radecka, K., & Zilic, Z. (2015). Movement analysis of the chest compartments and a real-time quality feedback during breathing therapy. Network Modeling Analysis in Health Informatics and Bioinformatics, 4(1), 21. Retrieved from: https://link.springer.com/article/10.1007/s13721-015-0093-2

Goodacre, S., Cohen, J., Bradburn, M., Gray, A., Benger, J., Coats, T., & 3Mg Research Team. (2013). Intravenous or nebulised magnesium sulphate versus standard therapy for severe acute asthma (3Mg trial): a double-blind, randomised controlled trial. The Lancet Respiratory Medicine, 1(4), 293-300. https://doi.org/10.1016/S2213-2600(13)70070-5

Graziottin, A., & Serafini, A. (2016). Perimenstrual asthma: from pathophysiology to treatment strategies. Multidisciplinary respiratory medicine, 11(1), 30. https://doi.org/10.1186/s40248-016-0065-0

Koninckx, M., Buysse, C., & de Hoog, M. (2013). Management of status asthmaticus in children. Paediatric respiratory reviews, 14(2), 78-85. https://doi.org/10.1016/j.prrv.2013.03.003

Lumb, A. B. (2016). Nunn's applied respiratory physiology eBook. Elsevier Health Sciences.

Maggiore, S. M., Idone, F. A., Vaschetto, R., Festa, R., Cataldo, A., Antonicelli, F., ... & Antonelli, M. (2014). Nasal high-flow versus Venturi mask oxygen therapy after extubation. Effects on oxygenation, comfort, and clinical outcome. American journal of respiratory and critical care medicine, 190(3), 282-288.
https://doi.org/10.1164/rccm.201402-0364OC    

National Asthma Council Australia. (2017). Australian Asthma Handbook. Access date: 15^th October. Retrieved from: https://www.nationalasthma.org.au/health-professionals/australian-asthma-handbook

Ostrom, N. K., Parsons, J. P., Eid, N. S., Craig, T. J., Stoloff, S., Hayden, M. L., & Colice, G. L. (2013, July). Exercise-induced bronchospasm, asthma control, and obesity. In Allergy Asthma Proc (Vol. 34, No. 4, pp. 342-8). Retrieved from: https://s3.amazonaws.com/academia.edu.documents/45451625/Exercise-induced_bronchospasm_asthma_con20160508-12306-1mov5v5.pdf?AWSAccessKeyId=AKIAIWOWYYGZ2Y53UL3A&Expires=1539588793&Signature=8c3N6pAlV3gYnErHREV0P2YHKRg%3D&response-content-disposition=inline%3B%20filename%3DExercise-induced_bronchospasm_asthma_con.pdf

Peytremann?Bridevaux, I., Arditi, C., Gex, G., Bridevaux, P. O., & Burnand, B. (2015). Chronic disease management programmes for adults with asthma. Cochrane Database of Systematic Reviews, (5). https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD007988.pub2/abstract

Shan, Z., Rong, Y., Yang, W., Wang, D., Yao, P., Xie, J., & Liu, L. (2013). Intravenous and nebulized magnesium sulfate for treating acute asthma in adults and children: a systematic review and meta-analysis. Respiratory medicine, 107(3), 321-330. https://doi.org/10.1016/j.rmed.2012.12.001