The Essay Explores The Respiratory System, Cardiovascular System, And Asthma.

Alex is a twenty-year-old young man who has had asthma since early childhood. He is maintained on Symbicort 160/4.5 micrograms two puffs, twice daily and salbutamol inhaler as needed. He smokes hand rolled cigarettes and marijuana. He is allergic to birch pollen and rye grass.

He is admitted through accident and emergency with a life-threatening exacerbation of his asthma. He has an IVI in situ and is receiving high flow oxygen through a mask.

On arrival he is confused, agitated and unable to communicate any information. His girl friend is with him and when asked states that the attack came on very suddenly and he became ‘delirious’. She was also concerned because his mood had been low recently

On examination
His breathing was noisy laboured and rapid with a rate of 33 breathes per minute. He was unable to speak because of the dyspnoea. It was noted that he was using all his accessory muscles but all respiratory movements were symmetrical
There was wheezing on both inspiration and expiration but more marked on expiration

It was not possible to measure his peak expiratory flow rate because of his respiratory difficulties
He was centrally cyanosed

His pulse rate was 135 beats per minute and regular with a BP of 130/75 mmHg
O2 Saturation was 85% on the high flow oxygen via a mask, Arterial blood gas analysis showed that his PaO2 was 7.4 kPa his Pa CO2 was 7.5 kPa
A neurological assessment was carried out that indicated that he was confused as to time and place.
Treatment

Oxygen given at 60%
Hydrocortisone 100mg IVI
Magnesium sulphate 1.2g IV over 20 minutes
5mg salbutamol nebuliser back-to-back

With reference to altered physiology discuss the relevance of the observations and test results. Discuss the care he will require during the first 4 hours giving reasons.
 

Physiology of the respiratory system

The respiratory system is responsible for the exchange of respiratory gases between the lungs, blood and the tissues. The movement of the diaphragm assists process of inhalation and exhalation, and air enters and exits the lungs via the trachea and network of bronchi (Broussard, Hall and Levitzky 2014).The oxygen rich air enters the alveoli of the lungs via the bronchi and bronchioles, and gaseous exchange occurs with the blood flowing through the capillaries lining the alveoli. Oxygen in the lungs is picked up by the haemoglobin in the red blood cells due to its higher partial pressure in lungs, while carbon dioxide from the RBC enters the lungs due to its higher concentration in the blood. Similarly, in the tissues, the oxygen concentration is lower, and that of carbon dioxide is higher compared to the blood flowing through capillaries around them, which facilitates the transfer of oxygen into the tissues and carbon dioxide out of it to the blood stream, which finally is carried to the lungs (Dugar, Latifi and Mireles-Cabodevila 2018).

The cardiovascular system is responsible for the circulation of blood in the body, with the heart actively distributing the body, and pushing the blood through a network of arteries, capillaries and veins (Bhf.org.uk 2017). The arteries carries the oxygenated blood to the body (except pulmonary artery) and the vein carries the deoxygenated blood back to the heart (except pulmonary artery), thereby forming the systemic circuit (Scanlon and Sanders 2014).

At normal conditions, the vital signs of the body are, Body Temperature between 36.5 to 37.5^oC ; Blood Pressure less than 135/85units, A pulse rate of 60-80 heart beats per minute, Respiratory Rate 12 to 20 breaths per minute (NICE.org.uk 2018).The normal level of arterial oxygen is between the ranges of 95 to 100 mm Hg, with values under 80 indicating the requirement of supplementary oxygen, (NICE.org.uk 2018). 

Asthma is a chronic condition, in which epithelial and mucous lining of the bronchi or the air passage to the lungs becomes inflamed and obstructed, and may be accompanied by stiffening or tightening of the muscles around them. This can cause shortness of breath, tightness in the chest, difficulty breathing and sometimes a wheezing sound during breathing.The obstruction of the airways and associated rigidity of the respiratory muscles can be due to inflammatory reactions and bronchial hyperactive responsiveness that can cause broncheospasm and increased secretion of mucus by the bronchial lining, thereby obstructing the airway (Tanizaki et al. 1984). The inflammatory reaction can be due to an allergic response of the body.Murdoch and Lloyd (2010) pointed that allergic asthma can cause airway inflammation, decline in respiratory activity and remodelling of tissues, and can be due to a complex interaction between genetic predisposition (allergy to certain substances) and environmental conditions (like dose and time of exposure to allergen, and co-exposure to infections).The allergens in turn can induce an inflammatory response in the air passage and atopy (predisposition to develop allergic disease) (Kuby 1994).  The allergens have been seen to produce hypersensitivities within the patient by activating the synthesis of histamines and cytokines. The cytokines have been seen to initiate complimentary immune reaction resulting in the development of conditions known as hay fever.

Physiology of the cardiovascular system

Figure 1: Genetic and Environmental Interaction in Asthma; source: (Murdoch and Lloyd 2010).

This difficulty in breathing, also results in a decreased oxygenation and respiratory distress, leading to physiological (lack of oxygen) and psychological (panic attack) stress, of which both causes and elevation in the heart rate or pulse rate (Asthmasymptoms.org. 2017). Hypertension is a condition where blood pressure rises in response to acute changes and returns to its normal state after a significant amount of time. Some of the underlying the conditions for the same could be high cholesterol in the blood.Whilea continued deprivation of sufficient amounts of oxygen to the body can cause reduction in oxygen saturation in arterial blood.The change in the partial pressures of these respiratory gases further affects the exchange of the gases, causing further deprivation as was seen with the patient. The difficulty in breathing and an insufficient respiratory function also has a significant effect on the nervous system, like stress, anxiety, (Hatfield 2017).The reduction of oxygen supply to the brain also can cause delirium (confusion), disorientation and panic (nhs.uk. 2017). This explains the state of confusion exhibited by the patient.

The laboured breathing and wheezing sound is possibly due to bronco-constriction and bronco-spasm that blocks the air passage, and makes the adjoining muscles to stiffen. The muscles contract under the influence of the parasympathetic nervous system (Shimoda et al., 2016).This causes a difficulty in inhalation and exhalation, as the air passes narrows down, and more energy is spent to move the respiratory muscles.The skin of the patient also showed cyanosis or discoloration (near the thorax, lips, and tongue) that can be due to an increased concentration of deoxyhemoglobin (or carbon dioxide in the blood) in the skin and mucous membrane, and is a symptom of central cyanosis.

The blockage and inflammation is due to the allergic reaction or hypersensitivity to certain allergic substances. The patient has a history of asthma, and allergy to birch pollen and rye grass. This can explain the sudden onset of the allergic reaction (due to the entry of the allergen in the respiratory tract). The allergen can therefore trigger the immune system to initiate an inflammatory response, causing inflammation of the epithelial lining of the bronchi, and an increased mucosal secretion, causing blockage of the air passage. This ultimately can cause poor ventilation or respiratory output, lower the oxygen saturation in the blood, and cause oxygen deprivation in the brain. The nervous system responds to the oxygen deficiency by triggering a panic attack, and hyperventilation response. Lower oxygen level to the brain also causes confusion and delirium because of its effect on the neuron function. The hyperventilation causes an immediate elevation in the rate of breathing and the heartbeat, in order to increase oxygen supply to the body. The rapid beating of the heart also increases the blood pressure, while the continued low levels of oxygen absorbed by the lungs causes a rise in carbon dioxide levels, and a decrease in the partial pressure and saturation of oxygen.

Normal vital signs and physiological parameters

Murdoch and Lloyd (2010) pointed that inflammatory reaction is mediated by T Helper Cells (T-h), in response to airborne allergen. The allergic reaction can be because of a genetic predisposition that facilitates the rapid release of Immunoglobulin E on the target tissues of the respiratory system, like the musoca. Scanlon and Sanders (2014) also stated that the asthmatic reaction could be linked to atopy. Proinflammatory mediators like histamine, eicosanoids, and reactive oxygen species (ROS) causes constriction of the smooth muscles, secretion of mucous and vasodilatation. The inflammatory mediators additionally inducemicro vascular leakage, thereby leaking plasma into the air passage, causing a thickening of wall of the airway, and edema. Presence of plasma in the air passage can also reduce mucous clearance and luminal plugs that obstruct the airway (Bouscet et al. 2000). The thickening of the walls of the bronchi can also an increase in the smooth muscle mass, occupying up to 20% of the thickness of the wall of bronchi and peripheral airways. This can be the result of the inflammatory cytokines, growth factors and histamine released at these target sites. These structural changes can build up over time, and can reduce the amount of oxygen reaching the lungs.

Studies by Thomas et al. (2001) also show that hyperventilation is a common symptom related to asthma. Studies by Mahler et al. (1991) Shows that an aggravated respiratory response to physical activity occurs during airway obstruction and life threatening scenarios (Meuret and Ritz 2010).Papiris et al. (2002) pointed out thathypoxima, hypocapnia and respiratory alkalosis is a common symptom of asthma, and requires supplemental oxygen administration. These can be caused due to the use of high dose of beta-adrenergic antagonists, increased rate of breathing causing anaerobic metabolism in the ventillary muscles and an associated tissue hypoxia triggered by the overproduction of lactic acid, which is inadequately cleared by the liver due to hypo perfusion.The authors also adds that dynamic hyperinflation of lungs occurs due to the airflow obstruction, high ventilation demand of the body, short expiration time, increased activity of post-inspiratory muscles all of which disrupts the static equilibrium volume at the end of expiration  and also causes an increased mechanical load and elastic work during breathing. The hyperinflation causes a fluctuation in the venous return, and further cause left ventricular diastolic dysfunction and incomplete filling. This leads to an increased right and left ventricular after load, and cause changes in the blood pressure (Papiris et al. 2002). This can be used to explain the rapid breathing shown by the patient (as his body is not getting enough oxygen), and a rapid pulse rate (as the heart is trying to work overtime to supply enough blood to his lungs and tissues to maintain the required rate of gaseous exchange. Such is evidenced by a decreased oxygen saturation of his blood, and a decreased partial pressure of oxygen compared to carbon dioxide. 

Pathophysiology of asthma

It has to be mentioned asthma is progressive condition which has a severe detrimental impact on the functionality of the respiratory system. When triggered by allergen or pollutants, the exacerbation of the dyspnea often leads to severe conditions which can be fatal for the patient if external oxygen therapy if provided on an urgent basis. Additional to the asthma event, due to the presence of elevated level of carbon dioxide in blood further causedfatigue to his respiratory muscles facilitated the process of exacerbation that the patient had been suffering from. The patient also seemed to be confused, indicating that the lack of proper oxygenation is effecting his nervous system, and causing the panic and delirium. As the patient had been centrally cyanosed, due to the excessive level of de-oxygenation in the body and resultant enhanced concentration of deoxyheamoglobin, the patient was exhibiting bluish colouration of the skin and mucous membrane; this also suggests severe hypoxia or oxygen deprivation demanding immediate oxygen therapy.The patient was immediately administered oxygen through mask (at 60%) and intravenous drips for administering medicines (Hydrocortisone 100mg, Magnesium Sulphate 1.2g over 20min). Hydrocortisone was given to reduce the inflammation and swelling due to asthma exacerbation, Magnesium SulphateIV was given to prevent convulsions, and assist in broncho-dialation and anti-inflammatory action working as an adjuvant therapy (Short,WilliamsonandLipworth 2012). The patient was also given salbutabol nebulizer 5mg, back to back to maximize broncho-dialationand elevate the respiratory rate to normal level.

The immediate medical management that the patient would include pharmacologic therapy. The pharmacologic therapy can include short-acting beta 2 adrenergic antagonists to relieve the acute symptoms, Anticholinergics to inhibit muscarinic cholinergic receptors and improve the vagal tone of air passage, Corticosteroids to reduce the inflammatory symptom, improving airway function and administering Leukotriene modifiers for bronchoco-dialation, and immuno-modulators for suppressing the immune system that causes or aggravates inflammatory response (Nice.org.uk 2018).

There are different fundamental standards utilized as a part of assessing patients with Asthma. This includes ABCDE approach airway, breathing, circulation, disability and exposure (Yeung et al., 2014). All the above assessment elements should be carried out immediately and frequently in order to have the capacity to deal with any perilous issues or complexity that may emerge (Yeung et al., 2014).This will at present empower the nursing professional to understand when there is a requirement for additional assistance so as to have the capacity to call for help sufficiently early avoiding the risk of fatality or exacerbation of the patient (Yeung et al., 2014). Nursing management protocols that the patient requires are nursing assessment, nursing diagnosis, nursing care planning and goals, nursing interventions, evaluation and discharge and home care guidelines.

Triggers, symptoms, and complications of asthma

 During the nursing assessment, the respiratory status, adventitious breathing sounds, oxygen saturation, and vital signs are recorded. The nursing diagnosis is aimed to investigate improper airway clearance, improper exchange of respiratory gases, and anxiety.The nursing care plan and goals includes airway clearance, expectorating secretions or exudations, improving air exchange, reducing adventitious breathing sounds, reducing or removing congestions, identifying complications or challenges during treatment and plan for appropriate precautionary of preventative measure. The Nursing Interventions would include assessment of patient history, respiratory status, medication given, pharmacologic therapy and fluid therapy. Evaluation helps in the determination of effectiveness of treatment plan.The discharge and home care guidelines includes collaborating between patient and provider, providing health education, ensure compliance to therapy protocols, and perform home visits. 

While assessing Alex, the assistant nurse is needed to thoroughly assess the patient for the presence of any general indication of pain which incorporates cyanosis, perspiring, nasal flaring and breathing utilizing accessory muscles (Resuscitation Council, 2018). The nurse will be required to document the vital signs including the respiratory rate and oxygen saturation of the patient, the respiratory rate of the patient was 33 breath/min which demonstrates distress as the standard rate is 12-20 breath/min (Boccanfuso and O'Kane 2012). The next phase will require the breathing sounds of the patient to be assessed o check for the presence of adventitious breathing sounds (Resuscitation Council, 2018).Auscultating the chest is needed in the next step to check if there is presence of diminished bronchial breathing which may indicate at pneumothorax or the presence of pleural liquid that can cause a total impediment (Resuscitation Council, 2018). The oxygen saturation level of the patient was 85% on high flow oxygen via mask which indicates improvement in respiratory function upon external oxygen therapy.

In most of the medical and surgical emergencies, hypovolaemia is the most reason for shock except if demonstrated something else (Punekar, Shukla and Muellerova, 2014). The Capillary Refill Time(CRT) Alex had been recorded as 4 seconds, the ordinary volume is 2 seconds, hence, it can be mentioned that the CRT of the patient had been prolonged (British Resuscitation Council 2015). CRT demonstrates poor perfusion and somewhat tachycardia pulse of 135 beats/minute, blood pressure of 1130/75mm/Hg, which indicates that he is in compensated shock.

Regular reasons for unconsciousness are hypoxia, cerebral hypoperfusion, hypercapnia or utilization of sedatives (Resuscitation Council 2015). The basic preliminary assessment data for Alex incorporates checking the patient readiness and level of consciousness. Glasgow coma scale (GCS) score can likewise be utilized to evaluate the level of awareness, in this case the patient had been alert and responsive.The next assessment step was to take a blood glucose level test of the patient to avoid the chances of the patient going for a hypoglycaemic attack (Resuscitation Council, 2018). As the blood glucose levels of the patient had been 5.8mmol, it can be considered that the patient had not been under immediate risk of hypoglycaemic attack (Diabetes UK 2018).

In this respect, a number of vital signs can be taken into consideration which are blood pressure (BP),  respiratory rate (RR) and heart rate (HR). Hypoxia or hypocapnia can cause an increase in BP, RR and HR and to assess respiratory distress. Changes in the vital signs, depth and rhythm of breath can be an indicator of respiratory distress.

A neurological assessment could be undertaken to identify anxiety, confusion or delirium, as a sign of the brain being deprived of sufficient oxygen. Delirium and anxiety can further increase heart rate and blood pressure. Thepatient maybe seen to execute forced breathing which could be related with the condition of hypoxia within the patient.

An assessment could be undertaken for the diagnosis of any  abnormal or unusual sounds  (like a wheezing sound) as a sign of Broncheospasm, pneumonia or respiratory failure. In general, sounds during breathing can point towards airway obstruction and stiffening of the smooth muscles. Wheezing sounds are generally caused by broncheo-spasm can result in respiratory distress (Bardowell and Mahoney 2015; Baughman and Loudon 1984; Shimoda et al. 2016).

An abnormal breathing pattern can point towards an improper movement of air in and out of the lungs (Berman et al. 1981).An inspiration and expiration ratio could be analysed for the  identification of the breathing abnormalities. It could be calculated with the help of devices  such as wright respirometer.

Assessment for Dyspnea and fatigue- To identify respiratory distress. During distress, additional stress occurs on the respiratory muscles and associated smooth muscles trying to compensate for the reduced oxygen saturation in blood. The   condition could be prolonged for the   development of severe conditions such as cardiovasculardiseases, which results in development of an extensive pressure on the heart muscles as they are unable to get sufficient oxygen (Hobbs et al. 2016). This can lead to fatigue of the muscles, and a reduced ability of the liver to remove the lactates from blood.

Assessment of decrease in systolic pressure- To identify the effect of airway obstruction on the cardiovascular system. A drop in the systolic pressure to more than 12mm Hg is an indicator of severely obstructed airway. This could be measured with the help of a sphygmomanometer. The device helps in the measurement of the orthostatic changes  which are are reflective of the anomaly  in the blood  pressure.

Monitoring blood oxygen saturation level- To identify the amount of oxygen carried by the haemoglobin. A saturation level below 90% is an indicator of hypoxima. Low oxygen saturation means that the blood is unable to supply sufficient oxygen into the tissues and therefore causing  a  deficit  in oxygen (Teng 2006).

Assessment of arterial blood gases- To identify presence of respiratory alkaloids due to distress and respiratory acidosis indicating respiratory failure. Respiratory alkaloids or acidosis is caused due to the elevated levels of carbon dioxide accumulated in the body, therefore causing a lowering of pH levels due to an increase in the acidity of blood (formation of carbonic acid). In worst cases the  patient could develop  conditions such  as excessive  saturation of carbon  monoxide within the blood which could  lead to asphyxiation  within the patient.

Elevating the level of head and bed- To assist maximum elasticity to lungs. Elevating the head also assist the flow of residual air out of the lungs, and facilitate the inflow of fresh air (with more oxygen). It is one of theevidence basedpractices whichcould be implemented by the nurse over here.

Helping patient to breathe using pursed lip- To improve breathing and driving out old air out of lungs. Improving breathing efficiency can also improve oxygen saturation in lungs. The implementation of  some of the evidence based practices  is dependent upon  the level  of expertise and knowledge professed by the nurses.

Short acting beta 2 adrenergic agonists like Albuterol, Levalbuterol or Terbutaline- For Broncho-dialation relaxing the smooth muscles associated with the air passage and treating acute exacerbation. 

Administering inhaled corticosteroids like Budesonide, Fluticasone, Beclomethasone or Mometasone.- To reduce the inflammation of the air passage and mucous secretion a  number of  corticosteroids  need to be provided to the patient.

General anaesthesia- general anaesthesia have been seen to result in  a number of complications such  as produce supraventricular arrhythmia,  which could  become worse with asthmatic complications. Therefore, adequate  ventilation  support need to be provided  to the patient.

Magnesium Sulphate- To assist Broncho-dialatory and Anti-inflammatory treatments.

Heliox (mixture of helium and oxygen)- Using Helium can decrease airway resistance, thus reducing distress. This is because helium is lighter than oxygen, and therefore will face lesser resistance in the narrow air passage.  However, a number of factors  need  to be consideration  such as  presence of allergies  within the  patient towards gases such as helium  which  could  enhance  bronchospasms.

Studies strongly suggest that the physical well being is integrally related to the mental wellbeing of people. Mental health problems such as depression or anxiety can increase the risks of several diseases such as cardiovascular disease, hypertension and stroke. A negative state of mind can also affect the daily activities and reduce social interactions, further increasing the rists of other mental health condition and reduce levels of self care. This eventually leads to an overall decrease in the physical well being of the individual. Such aspects are well observed in patients suffering from chronic depression and anxiety. On the other hand, a good mental state and emotional resilience can protect individual from mental health conditions caused due to exposure to stressful or adverse conditions. A positive or a good mental health also helps in the development of coping mechanism, helps in better emotional regulation, supports sustenance of healthy behaviour and thus promote both physical and mental well being. This connection between the mind and body thus has the potential to either promote or compromise the overall health status of people. 

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