Category: SARS

Introduction

Acute Respiratory Distress Syndrome (ADRS) is a chronic reaction to acute infections or injuries of the lungs. ADRS is not a disease but rather a syndrome triggered by diverse direct and indirect factors. The parenchyma of the lung becomes inflamed, causing impairment in the process of gas exchange. Concomitant release of mediators that are responsible for inflammation takes place systematically leading to hypoxemia, and severe organ failure (Aboab et al. 2000). The condition is often acute and chronic necessitating the patient to be admitted in an intensive care unit and be put under mechanical ventilation (Sundaresan et al 2011, p.1). The lung of a person suffering from ADRS is referred to as a baby lung because it is smaller and stiffer.

Dead space ventilation involves use of gas that does not interact with pulmonary blood at any one time. The clinical importance of Deadspace Ventilation is the lack of physiologic benefit of the energy utilized to move the gas.Inefficient and inadequate flow of pulmonary blood results to an increase in dead space ventilation due to inadequate flow of blood in the lungs to exchange with the ventilation gas.

Dead space ventilation ratio is increased when the patient is undergoing mechanical ventilation and a ratio of 0.50 is considered normal. A ratio below 0.60 does not warrant any reason to obstruct natural respiration while a ratio of 0.60-0.80 portends chronic disease and indicates that the patient cannot handle prolonged natural respiration. This paper is an analysis of the relationship between ARDs and Deadspace ventilation.

ARDs deplete the capacity of lungs for ventilation. The patients are therefore admitted into the intensive care unit where they require mechanical ventilation (Sundaresan et al 2011, p.1). Through artificial management of ventilation, the mortality of patients suffering from ARDs has been increased. This has been achieved through strictly limiting the tidal volume and the maintenance of plateau pressure (Pplat) below 30cmH₂O. A bronchorial collapse partially or totally excludes certain compartments of the lung from ventilation. ARDS does not respond to administration of high concentration of inspiratory oxygen (Niklason, 2008). Dead space ventilation helps in delivering information about the relationship between body tissue and gas in terms of quantity.

Definition of Terms Relevant to Topic

Dead space ventilation is a form of mechanical ventilation. It is recommended for patients requiring support in elimination of carbon dioxide and in maintenance of oxygen. Ventilated patients usually suffer from abnormalities in the lung structure, obstructions in the airways, and damaged tissues of the lung (Forel et al. 2012).Mechanical ventilation is anchored on the concept that the behavior of air is similar to that of fluid since both air and fluid follow the path that has least resistance as they enter a surface.

The maximal pressure in the airways during respiration is known as Peak Inspiratory Pressure (PIP). PIP is used to measure the pressure in the major air paths in the lungs. Acute or Rapid changes in PIP normally indicate severe complications such as bronchospasm or plugging of mucus. Plateau Pressure (P_plat) on the other hand measures the pressure of airways at the last stages of inspiration and normally indicates the pressure in the alveoli.P_plat determines complications that are brought about by the ventilator such as volutrauma and must always be kept between 30-35 cm H₂O pressure.

The volume of air that is inhaled and exhaled during a respiratory cycle is referred to as tidal volume (Vt). Minute ventilation determines (MV) the levels of carbon dioxide in the blood. It can be calculated by multiplying the tidal volume with the respiratory rate (Charron et al., 2011, p.2). Increasing Minute Ventilation decreases the level of carbon dioxide in the blood by increasing the rate at which elimination of carbon dioxide from the blood takes place. Decreasing the M.V increases the level of pulmonary carbon dioxide by reducing the rate at which carbon dioxide is eliminated from the blood. The non-perfused areas in the natural respiratory tract are referred to as Dead Space (V_DS). Dead space describes the parts and components of the respiratory system that do not indulge in elimination of carbon dioxide.

The mean Distribution time (MDT) defines the time available for alveolar diffusion and distribution of tidal gas (Aboab et al., p.1). The ratio of the dead space versus that of the tidal volume determines the lungs capability to transport carbon dioxide. This process is affected by pathology as well as by settings of the ventilator. When blood perfusion and air ventilation do not match, there is an abnormal deadspace, which manifests itself in the form of disorders such as pulmonary embolism (Bhadade et al. 2011). The condition is characterized by ventilation of the alveolar while blood perfusion is not taking place. An increased VDS/VT ratio causes abnormal oxygenation and irregular ventilation.

The Fraction of Inspired Oxygen (FiO₂) connotes the percentage of oxygen in the air that the ADRS patient inhales. The FiO₂ of room air is 21%. Increase of The Fraction of Inspired Oxygen to levels beyond 60% is attributed to increase in production of free radical oxygen, which could harm the cells due to the toxicity of oxygen. Arterial carbon dioxide (PACO₂₎ decreases because of reduction in ventilation (Charron et al., 2011, p.2). Patients suffering from ARDS have poor respiratory systems and require The Fraction of Inspired Oxygen levels to be above 60% (Forel et al., 2012). High levels of Fraction of Inspired Oxygen are recommended for them even when they are in danger of oxygen toxicity. Mechanical ventilators are used in order to reduce The Fraction of Inspired Oxygen to safe levels.

Dead space ventilation allows the alveoli that do not take part in the ventilation process to expand and increase the surface are available for oxygenation and ventilation. The method is referred to as alveolar recruitment and it is achieved through maximizing the capillaries of the alveolar (Niklason et al., 2008). This way the deadspace alveoli are capable of remaining open and function effectively.

Associated Disease

ADRS is associated with ALI (Acute Lung Injury). This disease is characterized by injury of the lungs due to hypoxemic related disorders (Bhadade et al., 2011). It occurs when sepsis triggers systematic inflammation of the lung. Sepsis is a negative response by the body to a disease or an infection. It is caused by invasion and quick spread of bacteria in the bloodstream. The normal response of the bodys immune system is to fight diseases but on occurrence of sepsis, the immune system becomes agitated and overwhelmed. Primary ALI occurs when the liver is injured directly. For instance, it occurs when a person suffers from an infection of pneumonia. Secondary ALI is normally caused by indirect injury on another organ of the body such as an infection of the pancreas. It is severe but is not as fatal as ADRS.

Clinical/Physiological Effects

It is estimated that one-third of the people who suffer from ARDS end up dying from the disease. The survivors are able to recover the normal functioning of their lungs though most of them contract mild permanent damage of the lungs. During the time that the lungs are not functioning properly, the brain does not receive sufficient oxygen as a consequence brain damage occurs (Forel et al., 2012). ARDS patients therefore suffer from memory loss and a host of other psychological problems.

Current Therapy

Dead space ventilation can take various forms. In Controlled Mechanical Ventilation, the ventilator takes up the complete role of breathing. A rate and volume is set for the ventilator. The patient cannot breathe naturally in this mode because he is completely sedated and almost paralyzed. This mode is not comfortable for the patient and is highly discouraged.

In intermittent mechanical ventilation, the mechanical ventilator is set in such a way that it conveys a certain number of breaths each minute with a regulated tidal volume. The patient has the freedom to breathe in and out without depending on assistance from the ventilator. Pressure is added to the breaths generated by The Intermittent Mandatory Ventilation so that the extra pressure supports the patient when taking own breaths because a lot of energy is expended in inhalation. By increasing the pressure, the workload of breathing is reduced and the patient is able to generate high spontaneous tidal pressure (Bhadade et al., 2011).

The Intermittent Mechanical Ventilator method was traditionally used to wean the patient but modern physicians have stopped its use as it causes tremendous muscle fatigue on a respiratory system that has not fully recovered.

Pressure control ventilation modes are recommended over volume control ventilation modes because they pose less risk of injuring the alveolar. This is because they decrease the level of stretching that the alveolar undergo in weak lungs such as those of people suffering from ARDS (Niklason et al., 2008).The tidal volume is not set but it is achieved through changes in the pressure. Patients are encouraged to breathe spontaneously when pressure is at the highest level.

High-frequency ventilation employs a technique similar to the Airways Pressure Ventilation but small breaths are rapidly delivered to the patient (Aboab et al., 2012). The rapid frequency of delivering breath keeps the alveoli open allowing oxygen to be delivered easily and carbon dioxide to be eliminated without complications. This method requires the patient to be sedated and paralyzed. In the pressure support method, the ventilator is set to deliver a regulated amount of pressure when the patient initiates natural breath (Sundaresan et al., 2011).

Positive End Expiratory pressure (PEEP) has been hailed as one of the most important mechanisms in management of ADRS patients. It promotes alveolar recruitment at the termination of expiration by maintaining the unstable units of the lung in an open state (Sundaresan et al., 2011, p.2)

Effects of Therapy

Dead space ventilation mechanisms usually create complications such as volutrauma, hypotension, and in some cases Ventilator Associated Pneumonia. Volutrauma increases the risk of death and multiple organ failure and is associated with high chances of death in the intensive care unit (Forel et al., 2011, p.8). Volutrauma can be avoided by keeping plateau pressures as low as possible. Hypotension is caused by reduced pleural pressure resulting from introduction of positive pressure. It can be reversed by administering fluids and adjusting the ventilator. Ventilator associated pneumonia is a fatal complication that arises from deadspace ventilation. It increases the patients mortality, morbidity, and the time-span during which the patient is supported by the ventilator.

Ventilator associated pneumonia is usually treated by use of antibiotics that act on the pathogens that are under suspicion and employment of bronchoscopy mechanisms. The condition can be prevented by shortening the periods during which the patient undergoes mechanical ventilation (Niklason et al., 2008). The patient should also be places in a semi recumbent position as opposed to a supine position.Patients also suffer from deep vein thromboses, decline in nutritional condition and pressure ulcers. Non-invasive ventilation procedures are being called for and they will soon phase out mechanical ventilation procedures. The methods use nose and mouth masks in place of tubes.

Role of the Respiratory Therapist

The respiratory therapist should be actively involved in provision of the appropriate nutrients to patients who have undergone deadspace ventilation. The therapist should design regimens of nutrition that are patient-specific (Bhadade et al., 2011). In addition, they should always ensure that adequate oxygenation is provided, ensure that the hemodynamic function is supported and that the airway is maintained. Perfusion of the ARDS patient must be maximized in the blood capillary system and this can only be done by increasing fluids to ensure that oxygen is readily transported between the pulmonary capillaries and the alveoli. The therapist needs to constantly evaluate the patients blood pressure, pulse pressure of the arteries, cardiac index, and the level of the oxygen saturation.

Positioning of the patient is also integral to recovery. The Prone Position (PP) has been advocated for as the most efficient one in critical care. This is because it permits the slow compartments of the lungs that had been excluded from respiration by ADRS to be recruited (Charron et al., 2011, p.2). The therapist should implement kinetic therapy, and the lateral rotational therapy. The therapist should also keep monitoring and evaluating the patient for changes in the respiratory cycle and status such as reduced oxygenation, decreased saturation, increase in the rate of respiration and quick breath sounds (Niklason et al., 2008).

The therapist should also provide dexterous skin care of the patient to avoid pressure ulcers, utilize devices that relieve pressure such as air mattresses, and continuously monitor the patients nutrition condition.

Summary

Physicians and respiratory therapists working with ARDS patients undergoing deadspace ventilation should have extensive knowledge of the entire ventilation process so that they are in a position to provide the best medical care. The medication taken by the patient is affected by the mode of deadspace mechanical ventilation that the patient has undergone.

Pharmacologic and ventilation technologies and therapies are evolving rapidly and physicians must be on the lookout for the new regimens and their advantages over traditional approaches. Respiration therapists must always keep in mind that the mode of mechanical ventilation used affects delivery of medication, analgesia, and sedation to the patient. Weaning is very important in shortening the time that the patient spends in the intensive care unit. Non-invasive ventilation involving the use of masks rather than tubes contributes to optimum critical care of an ARDS patient, thus it is highly recommended.

Reference List

Aboab, J. et al. (2012). Dead space and CO2 elimination related to pattern of inspiratory gas delivery in ARDS patients. Critical Care, 16 (R39), 1-8. Web.

Charron, C. et al. (2011). PaCO2 and alveolar dead space are more relevant than PaO2/FiO2 ratio in monitoring the respiratory response to prone position in ARDS patients: a physiological study. Critical Care, 15 (R175), 1-10. Web.

Forel, J. et al. (2012). Ventilator-associated pneumonia and ICU mortality in severe ARDS patients ventilated according to a lung-protective strategy. Critical Care, 16(R65), 1-10. Web.

Sundaresan, A. et al. (2011). Model-based optimal PEEP in mechanically ventilated ARDS patients in the Intensive Care Unit. Biomedical Engineering OnLine, 10(64), 1-18. Web.

Bhadade, R. et al. (2011). Clinical Characteristics and Outcomes of Patients with acute lung Injury and ARDS. Journal of Post Graduate Medicine, 574 (286).

Niklason, J. et al. (2008). The Influence of Venous Admixture on alveolar dead space and carbon dioxide exchange in acute respiratory distress syndrome; Computer modeling. Critical Care, 12 (R53), 1-7. Web.

Since the illness was first reported in Asian in 2003, the severe acute respiratory syndrome (SARS) has been studied in depth, especially at the microscopic level. Within a short period, the disease spread over all the continents except Africa, but was successfully contained. Nevertheless, it is still one of the major threats to the world health because it has a rapid rate of infection, spreading and a very high mortality rate (Peiris, Lai, Poon, et al 2003).

SARS is a viral disease caused by the SARS-associated coronavirus (SARS-CoV) of the viral order Nidovirales, Family Coronaviridae, Subfamily Coronaviridae, Genus Bectacornavirus and Species SARS Coronavirus. The virus belongs to the Group IV ((+)ssRNA), meaning that is it a positive single stranded RNA virus (Thiel 2012). The SARS Coronavirus is a large virus, with about 29kb long genome. So far, 13 genes and 14 proteins have been identified by molecular studies conducted since 2003. In addition, studies have shown that the genomes 5UTR and 3UTR have about 265 and 342 nucleotides respectively (Snijder et al. 2003). Like other members of the coronavirus family, the SARS virus expression begins with a single translation of 1a and 1b polyproteins from two large ORFs (Rota et al. 2003).

According to McBride and Fielding (2012), most of the protein functions of the genome products of the virus have been elucidated and are well known. For instance, the two large ORFs, 1a and 1b encode an enzyme replicas, as well as the codes for the proteins that end up making the structure of the virus. Although major studies have been conducted to examine these sections, the functions of the 8 proteins are not well understood.

Like other members of the family, the SARS virus expresses the ORF1a polyprotein (pp1a) and the pp1b polyprotein joined together (Rota et al 2003). The large proteins are then cleaved into 16 smaller functional subunits by proteins PLpro and 3CLpro (Thiel 2012). After this, the normal replication process of positive single stranded RNA viruses takes place, producing a large number of viruses that are highly infectious.

The disease resulting from an infection with the SARS virus is simply known as SARS. The initial symptoms are fever, headache and muscular pain. After about 2 days to 2 weeks of the first symptoms, the patients show a number of other conditions associated with respiratory system, which include pneumonia, cough and dyspnea (Thiel 2012). Hematologically, the patients experience a rapid reduction in the volume of lymphocytes within their circulatory systems.

The highest recorded mortality rate due to the condition was recorded in 2003 and was about 50% among the people aged 50 and above (Thiel 2012). In younger generations, the mortality rate was often low, mostly less than 45% in various nations in Asia (Thiel 2012).

In conclusion, SARS is a viral disease with a high rate of spreading and a high mortality rate. Alongside Ebola and H1N1, the virus poses a major threat to the population in the modern world.

References

McBride, R & Fielding, BC 2012, The role of severe syndrome (SARS)-coronavirus accessory proteins in virus pathogenesis, Viruses vol. 4, no. 11, pp. 290223. Web.

Peiris, JS, Lai, ST, Poon, LL, et al. 2003, Coronavirus as a possible cause of severe acute respiratory syndrome, Lancet, vol. 361, no. 9366, pp. 131925. Web.

Rota PA, Oberste MS, Monroe SS, Nix, WA, Campagnoli, R, Icenogle, JP & Bellini, W, 2003, Characterization of a novel coronavirus associated with severe acute respiratory syndrome, Science, vol. 300, no. 5624, pp. 1394-1399. Web.

Rota, PA, Oberste, MS, Monroe, SS, et al., 2003, Characterization of a Novel Coronavirus Associated with Severe Acute Respiratory Syndrome, Science, vol. 300, no. 5624, pp. 13949. Web.

Snijder, EJ, Bredenbeek, PJ, Dobbe, JC, Thiel, V, Ziebuhr, J, Poon, L, & Gorbalenya 2003, Unique and conserved features of genome and proteome of SARS-coronavirus, an early split-off from the coronavirus group 2 lineage, Journal of molecular biology, vol. 331, no. 5, pp. 991-1004. Web.

Thiel, V 2012, Coronaviruses: Molecular and Cellular Biology, Caister Academic Press, London. Web.

A histological analysis of SARS will be developed to clarify the main signs and symptoms of the disease, its epidemiology and etiology, the histological changes, and the existing treatments. SARS stands for severe acute respiratory syndrome. It is a viral respiratory disease that is usually caused by the presence of a coronavirus, known as an SARS-associated coronavirus, in a human organism (Centers for Disease Control and Prevention, 2013). Its fatality rate is approximately 10% (Van den Brand, Haagmans, van Riel, Osterhaus, & Kuiken, 2014).

Clinical Signs and Symptoms

Many people are not able to recognize SARS in its first stages because of its flu-like symptoms and signs. People may suffer from chills, pain in muscles, and possible diarrhea. Diarrhea is explained by the active viral replication that occurs in entrecote and disrupts the intestinal architecture (Van den Brand et al., 2014). Such symptoms as a fever up to 38⁰C, dry cough, and even shortness of breath are observed. In some cases, people with the SARS-associated coronavirus in their systems may have malaise, vomiting, and headache (Hui, Memish, & Zumla, 2014). All these signs could be observed among patients with different diseases.

Certain laboratory tests and radiological features have to be taken into consideration. Besides, people have to be careful with such risk factors as recent travels to the exotic or Asian countries, diabetes, smoking, heart diseases, and even hypertension (Doherty, 2013). Clinical and laboratory data on SARS is limited, and people continue developing the methods to recognize the disease under analysis. Therefore, SARS patients and their families are still under a threat of being maltreated or mistakenly diagnosed even in the hospitals with a good reputation.

Epidemiology

Adults are usually under a greater threat of having SARS in comparison to children (Hui et al., 2014). As for the gender factor, 57% of females and 43% of males are recorded as those who have SARS. Most cases of SARS were observed in young adults. Taking into consideration these criteria and risk factors, it is possible to say that smoking females between 25 and 35 years introduce a group of people that could be highly affected by the SARS-associated coronavirus and even die because of the development of this disease in their organisms.

According to the information given by the World Health Organization, the citizens of China and Hong Kong should be worried about the outcomes of the SARS epidemic (Van den Brand et al., 2014). In November 2002, the first recognized SARS epidemic was observed in the Guangdong Province with more than 1000 patients delivered to the hospital with several pneumonia signs. The laboratory results identified the presence of the SARS-CoV despite a number of positive antibodies to that virus. 55 people died during the first epidemic of SARS. The second outbreak of the epidemic was observed in Hong Kong. During that epidemic, 30 people died because of SARS. In several years, in Canada, 10 people died in the SARS epidemic.

The first steps which representatives of the infection control organizations had to take were the necessity to remove communication and any other form of contact between the diseased and healthy people. People-to-people transmission of the virus was a serious discovery that could not be neglected.

Etiology

The spreading of the disease among different countries in a short period of time tells about the necessity to investigate the etiology and the causes of SARS. The main cause of the SARS epidemic in any country is the already identified SARS-associated coronavirus also spelled as SARS-CoV. It is an RNA-type virus with certain peripheral corona-like outgrowth (Van den Brand et al., 2014). Unfortunately, the nature of the transmission of the virus between people was not completely understood. Still, it is believed that, in most cases, the virus could be delivered through water droplets which occur during coughing or sneezing. Therefore, if people want to reduce the possibility level of getting SARS, they have to keep their distance from the affected groups of people. Hand hygiene, masks, and even eye protection means could be defined as good contributors to the protection against SARS.

People could take molecular tests and serological tests to identify the presence or prove the absence of the SARS-CoV in an organism. The determination of cytokines in plasma is one of the first stages of lab analyses (Van den Brand et al., 2014). Blood tests and the analysis of cell culture should also help in identifying the virus and the development of the disease that could lead to death.

Affected Systems

Despite too general signs and frequent causes of the disease, it may have a crucial impact on the work of different systems in the human body. The SARS-CoV may influence the immune system because of the necessity of immune and inflammatory cells to work hard and deal with the lesions caused by the SARS infection (Van den Brand et al., 2014). The central nervous system is under threat as well because of the pathology and possible degeneration of neurons in the human brain. The SARS-CoV may cause kidney problems. Therefore, the urinary tract infection cannot be neglected. Such sign as diarrhea is the reason to worry about the work of the gastrointestinal tract. Centrilobular necrosis influences the work of livers as well. Finally, necrosis of skeletal muscle and the changes in tissue should be taken into consideration.

Again, it is necessary to underline that not all aspects of the SARS epidemic have been identified and investigated. It could happen that other systems may be affected by the presence of the virus. The genomic sequences of the SARS-CoV cannot be detected using the cases available. Besides, the responses of the systems could depend on the age of a patient.

Histological Appearance Changes

Regarding the histology of a normal lung, all sections of lung tissue may be compared with a fine lace because of thin-walled alveoli as the main composition of a human lung. Bronchioles and alveoli are the main lung components through which the exchange of air occurs. There is a single layer of squamous epithelium in alveoli. In Figure A, it is also possible to observe a thin layer of connective tissue between the alveoli. Besides, there are many capillaries. In Figure A, there are several bronchioles, which are characterized by different size. In comparison to capillaries which are lined with the squamous epithelium, bronchioles are lined with other types of epithelium, known as columnar and cuboidal.

Histopathologically, the changes in the respiratory tract are usually characterized by diffuse alveolar damage (DAD) as a form of pulmonary injury that is inherent to many SARS patients because of the existing immunopathogenetic factors (Gu & Korteweg, 2007). In Figure B, it is possible to observe severe damaged caused by lung tissue. These changes lead to the formation of a hyaline membrane, edema, and fibrin exudation (Gu & Korteweg, 2007). In Figure C, the changes in lungs and the creation of the multinucleated cells (marked by arrows) are introduced. Figure D demonstrates the development of viral genomic sequence and the combination in situ hybridization with antibodies. The first arrow in Figure D represents an infected cell known as pneumocytes. The second arrow in the same figure represents an inflammatory cell with SARS virus (Gu & Korteweg, 2007). The third arrow shows a cell without a virus. Figure E demonstrates different sequences of SARS-CoV in cells. The first arrow is the infection of T lymphocytes, the second arrow is an uninfected CD3-positive cell, the third arrow is an ISH-positive cell, the fourth arrow is a pneumocyte with a positive ISH, and the fifth arrow is an ISH-positive vascular endothelial cell. Figure F shows how spleen tissue changes lymphocytes. Finally, Figure G shows how ISH signals define patients brain tissue (Gu & Korteweg, 2007).

Current Treatments

The incubation period for patients with SARS can last from 2 up to 10 days. The isolation of patients should occur in a short period of time. It is suggested to use negative pressure rooms so that even nurses may avoid direct contact with patients. Radiography helps to find out the measurements of the respiratory phase when the patients may or may not be dangerous for other people around. Current chiropractic treatment for SARS patients that is characterized by the absence of any surgeries for improving work of the system includes antibiotics such as amoxicillin or clarithromycin and glucocorticoid, which help to control cytokine responses, which are caused by SARS-CoV. The promotion of intensive care treatment in the form of aerodynamic ventilation is also required (Van den Brand et al., 2014). Finally, antiviral therapy should be offered as a general method of treatment for people, whose changes in the organism are caused by the presence of a virus.

Interest in the Topic

There are several reasons for why the SARS epidemic is chosen for the analysis. People know about the existence of this disease and learn how dangerous it could be for people regarding their gender and age factors. Besides, the location of people may contribute the development of the disease. In case one person gets SARS-CoV, there is a threat that more people, who are or were in close contact with a patient, could get the same health problem. Still, not many investigations could be found on the chosen topic. Even the experts could fail to diagnose the disease in time. People die horribly because of SARS, and researchers could say a little about the case (Doherty, 2013). As a chiropractor, I am interested in SARS because this disease may cause myopathic and neuropathic complications which are hard to detect and treat in a chiropractic clinic. New methods of treatment have to be investigated soon to be ready to help people with different phases of SARS. At this time, the only way that could be used to support infected patients is the provision of an incubation place for treatment and the experiences with an anti-viral therapy based on well-known antibiotics.

Conclusion

In general, the analysis of the SARS epidemic developed in this paper helps to clarify the weaknesses of research done on the topic and underline the major facts people have to be aware of. It is easy to get the virus, and it is hard to get rid of it without certain losses.

References

Centers for Disease Control and Prevention. (2013). About severe acute respiratory syndrome (SARS). Web.

Doherty, P.C. (2013). Pandemics: What everyone needs to know. New York, NY: OUP USA.

Gu, J., & Korteweg, C. (2007). Pathology and pathogenesis of severe acute respiratory syndrome. The American Journal of Pathology, 170(4), 1136-1147.

Hui, D. S., Memish, Z. A., & Zumla, A. (2014). Severe acute respiratory syndrome vs. the Middle East respiratory syndrome. Current Opinion in Pulmonary Medicine, 20(3), 233-241.

Van den Brand, J. M. A., Haagmans, B. L., van Riel, D., Osterhaus, A. D. M. E., & Kuiken, T. (2014). The pathology and pathogenesis of experimental severe acute respiratory syndrome and influenza in animal models. Journal of Comparative Pathology, 151(1), 83-112.

Introduction

Severe Acute Respiratory Syndrome (SARS) first appeared in February 2002 in china’s Guangdong province before emerging in neighboring Hong Kong in late February. The epidemic had an impact on tourism all over the world, particularly in South East Asia. Pine R (2004).

SARS cost the Hong Kong tourism industry HK $3.8 billion in 2002.

The death fall had risen to 270 and infections were totaling 1730. Tough penalties for spitting and uttering were raised from HK $600 to HK $1500 and prosecutions on offenders were intensified. Hong Kong’s economy had already grown weak due to the impact of SARS on the tourism industry. The healthcare system had to be reviewed to manage the crisis. Tourists dropped by 65% to 490,000. The hotel occupancy rate was below 20% and not the previous 81% and 79% from February to March. In April, the loss on GDP per month due to a fall in the hotel business, airline, and travel agents was HK$ 2 billion. May cost was HK$1.8 were issued World Health Organization travel alerts against Hong Kong. Launch of events and inducement programs to encourage courts is to the city of Hong Kong. The travel alerts were a source of worry to the tourists because they tried to avoid Hong Kong and targeted other tourist destinations.

Description of the disease

SARS is a communicable disease and with the spitting of and dirt environment, no foreigner wanted to be in Hong Kong. The launch of inducement programs was costly to the tourism industry and this affected profits because it was an unexpected cost on the profit and loss account. Research and development costs were incurred to determine the real cause of the Respiratory system. This also had an impact on the Balance sheet because profits appear on the balance sheet of every entity. Cash flow in the industry was reduced due to the increased spending. At times negative cash flow could be reported and the government had to increase its budget for the tourism industry. This was a reduction of the government funds due to the supplementary budget allocation. The launching of events to attract tourists had a negative implication on the profits and cash flow of the tourism industry because this was both for domestic and international tourism. Events could be at no cost because it was meant to entice tourists. Any expenditure without unmatched revenue is a loss to an entity and this can be noted in the reduced Gross Domestic Product. The Health Travel alerts were on the airline, hotel accommodation, and even on travel agents. These are sources of revenue to the government and any cost incurred by the three is a reduction of government revenue and a reduced government funding for the tourism industry, which also needed grants from other nations.

The review of the health care system

The review of the health care system has been facing difficulties. These range from lack of funds, lack of the required personnel, and corruption. This has reduced the most by the tourists reducing their number every year. This low standard of healthcare leads to the spread of SARS and loss in tourism revenue. The lack of inspection of the industry’s facilities by the government health officials can be associated with the death toll of 270 and 1730 cases of infection. This is a negative public image in the international scene and international tourists were not ready to be part of a foreign country’s health crisis and would better be in other tourism destinations around the world regardless of the Goodwill and relations that they had created before 2002, cases of lack of funds and misuse of the available funds, corruption can also be associated with the crisis in 2002 to the effects being felt at present.

Penalties

Tough penalties for spitting and littering were not a preventive measure enough. Curley M (2004). The 65% drop in tourists experienced in 202 has to lead to a decrease in Gross Domestic product annually after that time. Funding of the tourist industry by the government has been low. The industry doesn’t have enough for its research and development. The industry cant deal with other dimensions of growth and development and this has to lead to a stagnation of the industry due to old styles of operation. Computerization at all departments of the industry has been low and this has greatly delayed the progress in terms of effectiveness and efficiency of services offered. Hong Kong’s tourism industry is now below other parts of the world, which did not experience the same crisis and did not have to focus on such. Tourists are not interested in what happened in 2002 but are interested in where they can have fun at the moment and destinations that have not had cases of SARS.

The government has been trying to reserve the position but all in vain because statistics already show that b April 2002, the death toll for SARS in Hong Kong was 270, and infections at that time were 1730. Tourists are always looking for weak points in any tourist destination and their form a good ground for them to change the route. The goodwill that they have already created with other destinations cant be reversed and these new tourists destinations will continue enjoying the fruits of their tourism industry thanks to the impact of SARS in the Hong Kong tourism industry.

The inducement events and programs by Hong Kong to the tourist don’t add much value because SARS is something that already happened and can reoccur. Tourists consider their health more than the fun that they can have as tourists in Hong Kong. So their planes in Hong Kong have to remain suspended.

The increase in penalties from HK$600 to 1500 was not good enough. Offenders were not worried much about this and this did not stop them because they could do it at their own cost regarding less of the health implications. This is a habit that before had been used before the outbreak of SARS. Tourists did not care much about the penalty but were interested in the tourism industry dealing more with the cause of SARS, not the ways of spreading penalties could not reduce the spread of SARS and the tourists kept on watching the crisis from a distance but not in Hong Kong.

The tourism industry had to finance the clearing of streets, housing blocks, and the environment. Dirty streets residential areas and the environments were areas where the Acute Severe Respiratory Syndrome was being bred and this lead to a serious transmission of the disease to those working in airports, airlines, and travel agents. These were people in close contact with the tourists and acquisition of the syndrome was easy. These cleaning efforts were costing the concentration of tourism officials and management in the normal operations of the industry itself and there was a reduction in the quality and quantity of services. This was a weak point for Hong Kong tourism competitors because their services remained standard and tourists diverted to these destinations at the cost of Hong Kong. This meant that they could host the tourists for enforceable future because once bitten twice shy.

Waste disposal systems

Sewage pipes had to be worked on. At that time waste disposal systems were reported to be in a mess and might have been the cause for the outbreak. These were to be treated and repaired to avoid any future outbreaks. The SARS is communicable and there was a first-rate transmission in the business, travel agents, or even at airlines. Those working there could also get the same from ordinary citizens and hence transmission to the tourists was first. Sewage pipes in Hong Kong are widely connected and this covered the tourist points. Henderson JC (2004).

The HK$3.8 billion losses for the tourism industry occurring in April and May 2002 have never been recovered to date. Stakeholders in the industry for that financial year were paid out of Reserves. Debit on the Reserves account determines the balancing in the Trial balance account and the stability of the entity is therefore affected. The deficit in the Reserves due to the effect of losses out of SARS was to clear through funds from other accounts. This affects greatly affected the cash flow statement for 2002 and the opening balance of cash flow in 2003, 2004 to date.

Among the 230 deaths were officials in the tourism industry. They are people who had been trained and experienced enough to deal with tourists due to their experience for many years, these officials have never been replaced or those new officials are either not qualified or lack the experience required. Services have therefore been low and tourists have chosen other destinations hence giving tourism in Hong Kong a big challenge. Extra costs have been incurred in the restoration of its market leader position in the world and this has not been easy for the tourism industry’s management

The effect on the environment

The environment had to be improved because most tourist destinations are on the field and this could have resulted in more transmissions. The rough penalties for spitting and uttering offenses were meant to prevent more political of the environment. World Health Organization also was concerned because this was a serious health risk to the left of the world. This lead to the serious attention of Hong Kong at the international level and this negative publicity was working towards the coming down of the tourism industry. Interested tourists had to think twice before carrying on the Hong Kong soil and this further decreased the industry’s forecast of profits and variations profits did not impress the stakeholder of the industry and this reduced the finances to the industry and hence negative cash flows. SARS can be said to have hurt all the cash flows of the industry, which include the profit and loss account, the balance sheet, and the cash flow statement.

Recommendations after the SARS case in Hong Kong

Maintaining high standards of health and hygiene for the environment. A committee is necessary for the management and control of SARS all around the year and health guidelines in restaurants and public places.

Center for Disease Control and Prevention (2005)

Maintaining high standards for health and hygiene: SARS is a communicable disease and breeds most in unclean areas and the environment. Tourists are interested in only those areas in a country that they come into contact with. This includes airlines, hotels, and travel agents. If they notice something not hygienic and is against the standards of a healthy living trust me they will not visit Hong Kong anymore. The tourism industry is a major contributor to the exchequer of any country. The government allocates some budget for the industry from its revenue industries contributing a lot to the government revenue are allocated more funds for their development and growth. The tourism industry should therefore think of increasing its profits so that revenue to the government through taxes is improved.

Kercher B MC (2004)

The health ministry should therefore ensure that both health and hygiene standards are high because the focus should not only be on tourists but also the other citizens. Surveys by health officials should be regular to ensure that the airlines the hotel and travel agents maintain the same standards. The environment should be considered to ensure that every possible cause of SARS is avoided. Officials in the tourism industry should also have health certificates. The government of Hong Kong should issue the certificates after someone has gone through a thorough checkup for SARS and all other communicable diseases. This will deal with all causes of threat to the tourists because health is wealth to any elite.

Conclusion

In conclusion, the impact of SARS in the Hong Kong tourism industry was enormous and it leads to a decline in standards of the tourism services at that particular time. Same international tourists who changed their destinations at that particular time, 2002 have never returned and income to the industry has been greatly reduced. Future cases of communicable Respiratory syndromes should be avoided to keep off such crises. This can only be through observing high standards of hygiene at the airlines from and to Hong Kong routes, hotels business and in the travel agents. These are the point where the tourist can notice something funny, something that is an indication of a future outbreak of SARS and this may lead to moving effects on the industry as a whole. Chien (2003).

References

Chien, G. Cl. (2003). International journal of Hospitality Management. Volume 22, Number 3. Elsevier Publishers.

Chien G.CL. (2003). Impact of the Severe Acute respiratory Syndrome.

Curley N Thomas. (2004). Australian Journal of International Affairs Human Security and Public health in South East Asia.

Department of Health and Human Services; Center for Disease Control and Prevention (2005).

Henderson JC (2004). Managing a health related crisis; SARS in Singapore.

Kercher B Mc (2004). The overreaction to SARS and the collapse of the Asian tourism.

Lee JW. (2003). Health management. Brookings Institution.

Pine Ray. (2004). International journal of contemporary Hospitality. The impact of SARS on Hong Kong’s tourism.

Biotechnology has been one of the recent advancements from pure science. The right definition of biotechnology raises a number of correlated responses. This is because biotechnology is a new branch of pure science that is gaining fast recognition. Some of those outstanding responses that attempt to define biotechnology include the application of integration of biology and technology, a promising field that deals with using organisms, and a field of science that uses biological knowledge and strives to elucidate biology. In addition to these, other distinctive responses include artificial methods that involve the taking and application of technology and relevant tools that aid in the study of biology. In this regard, it is obvious that comments made out of attempts to appropriately define biotechnology are a result of five reasons. These include the facts that:

1. Biotechnology is new,
2. It is a tool,
3. It has a purpose to advance,
4. It is an artificial method,
5. It uses biology and technology.

This reflects that those with the proper level of education have come to appreciate the fact that biotechnology is an integration of biology and technology. Its purpose, therefore, is the achievement of some form of improvement from scientific facts to everyday applications. Although these facts are all valid as regards the definition and role of biotechnology in nature, it means much more than just these.

As has been demonstrated in recent decades, biotechnology has the capacity to increase the production, efficiency, and quality of crops. Economic forces always act to increase efficiency and production for better supply of our needs and for the provision of more and high-quality foods. They remain the most dominant forces in the supply of goods. To respond to the needs, these economic forces always enhance the promotion of the levels of production and quality of farm produce. For these reasons, it is true that economic forces have the ability to increase efficiency and production.

Towards this regard, our needs for the demand for an increase in quantity and quality foods can then be effectively solved. Furthermore, the American president clearly put it “As technology and information are…in almost every job …America is becoming more productive, and workers need…“. It is open evidence from our surroundings that our world is indeed changing by the adoption and integration of science and technology. This in turn increases the levels of productivity of foods and other social needs. In addition to the growing need for plenty and higher quality foods, the trend of increasing applications of biotechnology in both crops for direct consumption and other uses indicates additional evidence that integration of technology is playing a very important part in the satisfaction of our needs. Thus, I remain convinced, by facts advanced by this long discussion, to think that biotechnology use is increasing because of our need for more acceptable quality foods.

In addition to the above, an increase in the trend of biotechnology use in food production is evident. This is demonstrated by the fact that over 60% of soybean crops that are mostly used as livestock feeds are genetically modified (GMO) and this trend is expected to not only rise but also to continue. In contrast, GMOs only account for 24% and 20% of maize and canola, respectively. These two crops are mainly used for human consumption. It is therefore surprising that, GMOs account for almost double the production of non-food product cotton, with a production average at about 46% in comparison to that of maize and canola. These statistics reflect that we tend to tolerate biological modifications in natural crops and non-consumed products while widely reducing and limiting modifications in consumed products for the interest of safety. This eventually indicates our tendency to abandon benefits that come along with the adoption of science and technology due to our preference for a safe approach to biotechnology use. Thus, it is convincing to deduce that the extent and degree of biotechnology use not only depends on but is also limited by our preferences for its use.

The role of biotechnology cannot be underestimated. Diseases such as SARS are capable of causing a tremendous fatality and mortality rates and have the capacity to spread widely in today’s world. This realization raises the need to accurately anticipate the outcomes of tragic events such as a SARS outbreak. In the case of SARS, biotechnology was appropriately used in direct response to this need. Analysis conducted with computer applications, mathematics, biology, and technology mainstreams that made use of biotechnology-based on past events predicted that fatality and mortality rates would have been relatively large. It informed biomedical communities of associated costs of SARS as wells as the critical needs and importance of responding effectively and rapidly. The case of SARS was a reflection that we are successfully using this new field to meet our critical needs and remain protected from natural harm.

In response to SARS, biotechnology was used by government agencies and think tanks all around the world to progressively research useful facts that include antibodies and genetic sequences that were central in the production of diagnostic tools, drugs for treatment, and vaccines. These formed the foundation of our ability to implement workable solutions capable of confronting and combating SARS. It, therefore, demonstrates that there is a need to seek this new applied science to confront the challenges in biomedical crisis and problems. Both early anticipation and our earnest attempts to combat SARS with biotechnology convinced me that biotechnology can be extensively used to meet the critical needs for our protection from natural harm.

However, biotechnology revealed its limitations when it failed to provide us with solutions before the conventional method of quarantine effectively brought an end to the SARS crisis. It is therefore sadly evident that with its large number of advantages, biotechnology is widely limited in its ability to solve problems, at least within a limited timeframe. As organisms, we evolve and survive on this planet by mere fate because nature cannot grant us food nor protect us from its harms in the form of diseases and illnesses. In light of this reality, food and protection (from natural harm) form our critical needs. Consequently, in response to these needs, there is a need to integrate biology and technology (biotechnology) and apply this gift to take care of these needs. One basic challenge that still remains in the adoption of biotechnology is that our application is limited by our preferences on “how to use it” and naturae limitations in biotechnology.

Introduction

Severe Acute Respiratory Syndrome is one of the many viral respiratory diseases that emanate from the SARs coronavirus (Hui, Memish, & Zumla 2014). The disease originated in Southern China between late 2002 and mid-2003 (Hui, Memish, & Zumla 2014). At the onset of the disease outbreak, the immediate number of death cases amounted to 774. The disease affected 8,096 people including the number of deaths reported especially in Hong Kong (Hui, Memish, & Zumla 2014). Several other countries were also affected in the region.

Spreading the virus

Earlier on, coronavirus did not have such harmful effects on humans. The SARs strain has however changed this fact since its outbreak in 2002. The most notable spread of the disease is through the air (Yu, Qiu, Tse & Wong 2014). Therefore, the disease is faster spread through coughing, sneezing, and also breathing near an infected individual (Yu et at. 2014). Spreading the virus through personal contact with an infected person can be done through hugging, kissing, sharing utensils, and drinking from the same cup, direct touch, and proximity about 3 feet away from an infected person (Wildeman, Schnittker & Turney 2012).

Signs and symptoms

The disease is not contagious in its incubation period which lasts for about 2-7days (Yu et at. 2014). After the incubation period, in cases, the victim begins to experience a high fever. Alongside the fever, he or she experiences high temperatures and in most cases, it exceeds 38 degrees Celsius. In addition, the disease also has similar symptoms to those of the common flu. These symptoms include aches, chills as well as diarrhea (Yu et at. 2014). The victim may also experience very dry coughing and short breaths (Yu et at. 2014). Although at this point the symptoms are very mild, they further develop into more severe complications within a week. Such advanced complications include respiratory failure, heart failure as well as liver failure (Yu et at. 2014).

Test and diagnosis

There has not been a universal test that can specifically detect SARs. In fact, it is difficult to treat a patient who has been infected by SARs since there is no fast enough method to diagnose the treatment early enough. Normally, an infected person must have come into contact with a previously infected individual. Pneumonia is also a possible sign to diagnose a patient who is infected by SARs. (Cressoni et al. 2014). However, a patient is assumed to have SARs if he/she displays abnormal pneumonia.

Treatment and prevention

The treatment of SARs is similar to the treatment given for pneumonia especially the community-acquired atypical pneumonia (Franken, Ansems & Damink 2014). To prevent infections of the virus one should avoid physical contact with an infected person as well as avoiding sharing or contact of body fluids such as saliva and sweat. Basic personal hygiene is recommended in preventing the infection of SARs. This included washing your hands frequently, avoiding touching your mouth, and covering your mouth while coughing.

References

Cressoni, M., Cadringher, P., Chiurazzi, C., Amini, M., Gallazzi, E., Marino, A., & Gattinoni, L 2014, ‘Lung in homogeneity in patients with acute respiratory distress syndrome’, American journal of respiratory and critical care medicine vol. 189, no. 2, pp. 149-158.

Franken, M., Ansems, J., & Damink, B 2014, ‘Quality of medical technology for flexible endoscopes and disinfectsors’, Physica Medica: European Journal of Medical Physics vol. 30, no. 1, pp. 119-120.

Hui, D. S., Memish, Z. A., & Zumla, A 2014, ‘Severe acute respiratory syndrome vs. the Middle East respiratory syndrome’, Current opinion in pulmonary medicine, vol. 20, no. 3, pp. 233-241.

Wildeman, C., Schnittker, J., & Turney, K 2012, ‘Despair by association? The mental health of mothers with children by recently incarcerated fathers. American Sociological Review’, vol. 77, no. 2, pp. 216-243.

Yu, I. T. S., Qiu, H., Tse, L. A., & Wong, T. W 2014, ‘Severe Acute Respiratory Syndrome Beyond Amoy Gardens: Completing the Incomplete Legacy’, Clinical infectious diseases, vol. 58, no. 5, pp. 683-686.

Introduction

Severe acute respiratory syndrome (SARS) is a communicable disease that is caused by the virus SARS corona virus (SARS-CoV) (Coronavirus Research and SARS, 2004) The disease started in South China in early 2002. During the outbreak, mortality was highly dependent on age. Older people succumbed to the disease more than younger people did. The disease has not yet been eliminated from the human population. Scientists claim that it exists in natural reservoirs and may return to the human population any time.

Pathogen involved

SARS is caused by a virus in the coronavirus family known as SARS corona virus (SARS-CoV) (Coronavirus Research and SARS, 2004).

The defense-host disease

Both adaptive and innate immune responses are involved in SARS infections. However, adaptive responses are more involved because replication of the virus outpaces innate immune responses (Overview of the SARS, 2004). Both responses are involved because their interaction is very important.

Adaptive responses cannot be elicited without innate responses. After infection, the immune system uses nonspecific immune defenses to contain the spread of the virus in the body. In addition, it uses antigen specific immune responses to fight the virus. The main aim of these immune responses is to eradicate both host cells and virus particles involved.

Infection and transmission

SARS is transmitted through person-to person contact (Overview of the SARS, 2004). Transmission involves exposure of individuals to infectious droplets from infected people. In addition, it is transmitted through direct physical contact with body fluids of infected individuals (‘Overview of the SARS Epidemic’, 2004). Infectious agents are transmitted when the mucous membrane of the nose, eyes or mouth comes into direct contact with infected respiratory droplets or fomites.

Particles of the virus contained in transmitted respiratory droplets are the main cause of the disease. The particles attack epithelial cells and the lining of the mucosal membrane (‘The public health response to SARS’ 2004). With the aid of the synthetic mechanisms of host cells, the virus cells replicate and release new virus particles that attack other cells.

Clinical manifestations

The disease manifests itself through symptoms and signs that are typical to flu-like infections. These symptoms include chills, muscle and body aches, fever, and in some cases, diarrhea (The public health response to SARS 2004). After a week of infection, symptoms include dry cough, fever of 38 degree Celsius, and shortness of breath. If the disease is not diagnosed and treated early enough, it may progress to pneumonia or respiratory failure. In severe cases, it progresses to death.

Diagnosis and control

Diagnosis of SARS involves different types of tests. These tests include blood clotting tests, complete blood count (CBC), chest X-ray or chest CT scan, and blood chemistry tests (Denison, 2004). These tests take time to give results. However, health professionals use other tests that give quick results.

These tests include antibody tests, direct isolation of the virus, and rapid polymerase chain reaction (PCR) for the virus (Coronavirus Research and SARS, 2004). These tests have limitations because they cannot identify the virus during the first week of infection when the disease is most critical.

Control of SARS involves avoiding contact with infected people, avoiding travel to areas with outbreaks, and cleaning hands with alcohol-based disinfectants (Denison, 2004). In addition, avoiding sharing things such as utensils and food, wearing masks and goggles are also effective control methods (‘The public health response to SARS’ 2004). It is also advisable to close one’s mouth and nose when sneezing to avoid transmitting the virus to others in case one is infected.

References

‘Coronavirus Research and SARS‘ 2004, in S Knobler, A Mahmoud, S Lemon, A Mack, L Sivitz, and K Oberholtzer (eds.), Learning from SARS: Preparing for the Next Disease Outbreak, National Academies Press, Washington, pp. 19-22. Web.

Denison, M 2004, ‘Coronavirus Research: Keys to Diagnosis, Treatment, and Prevention of SARS‘, in S Knobler, A Mahmoud, S Lemon, A Mack, L Sivitz, and K Oberholtzer (eds.), Learning from SARS: Preparing for the Next Disease Outbreak, National Academies Press, Washington, pp. 149 – 157. Web.

‘Overview of the SARS Epidemic‘, 2004, in S Knobler, A Mahmoud, S Lemon, A Mack, L Sivitz, and K Oberholtzer (eds.), Learning from SARS: Preparing for the Next Disease Outbreak, National Academies Press, Washington, pp. 2-13. Web.

‘The public health response to SARS‘ 2004, in S Knobler, A Mahmoud, S Lemon, A Mack, L Sivitz, and K Oberholtzer (eds.), Learning from SARS: Preparing for the Next Disease Outbreak, National Academies Press, Washington, pp. 13-19. Web.

The article selected for the analysis describes an experimental study aimed to determine whether early physical therapy interventions in intensive care units are capable of improving health outcomes of patients suffering from acute respiratory failure as compared with a standard-of-care PT program. The experiment involved two groups of patients who required mechanical ventilation: the first group received PT in the standard-of-care manner (6.1 ± 3.8 sessions for 86 ± 63 minutes) whereas the second group participated in an intensive early mobilization program (12.4 ± 6.5 sessions for a total of 408 ± 261 minutes) (Moss et al., 2016). The experimental character of the study can be proven by the following arguments (Campbell & Stanley, 2015):

• it involves an intervention (as compared to the observation of naturally occurring events);
• the impact of the intervention is the main focus of the study;
• the research is prospective;
• it tests a hypothesis (not just describes the events);
• it seeks ways of improving real patients’ condition.

Thus, the appropriate representative will be: R (random sampling) O (data collection) X (intervention) O (data collection) for both groups as they both received PT but differently. Non-probability sampling was used as only those who received mechanical ventilation for at least 4 days were eligible to participate. The major advantage of this type of sampling is that it is purposive, which allows researchers to concentrate on a particular group of patients. One of the key disadvantages is that the results do not apply to other patients who do not correspond to the specified parameters.

The study involved a randomized trial as any patient meeting the requirements could become a member of the intervention group. This strengthens the study design by eliminating pre-judgment and reducing bias and spurious causality.

References

Campbell, D. T., & Stanley, J. C. (2015). Experimental and quasi-experimental designs for research. Memphis, TN: Ravenio Books.

Moss, M., Nordon-Craft, A., Malone, D., Van Pelt, D., Frankel, S. K., Warner, M. L.,… Schenkman, M. (2016). A randomized trial of an intensive physical therapy program for patients with acute respiratory failure. American Journal of Respiratory and Critical Care Medicine, 193(10), 1101-1110. Web.

Introduction

Acute Respiratory Distress Syndrome (ADRS) is a chronic reaction to acute infections or injuries of the lungs. ADRS is not a disease but rather a syndrome triggered by diverse direct and indirect factors. The parenchyma of the lung becomes inflamed, causing impairment in the process of gas exchange. Concomitant release of mediators that are responsible for inflammation takes place systematically leading to hypoxemia, and severe organ failure (Aboab et al. 2000). “The condition is often acute and chronic necessitating the patient to be admitted in an intensive care unit and be put under mechanical ventilation” (Sundaresan et al 2011, p.1). The lung of a person suffering from ADRS is referred to as a “baby lung” because it is smaller and stiffer.

Dead space ventilation involves use of gas that does not interact with pulmonary blood at any one time. The clinical importance of Deadspace Ventilation is the lack of physiologic benefit of the energy utilized to move the gas.Inefficient and inadequate flow of pulmonary blood results to an increase in dead space ventilation due to inadequate flow of blood in the lungs to exchange with the ventilation gas.

Dead space ventilation ratio is increased when the patient is undergoing mechanical ventilation and a ratio of 0.50 is considered normal. A ratio below 0.60 does not warrant any reason to obstruct natural respiration while a ratio of 0.60-0.80 portends chronic disease and indicates that the patient cannot handle prolonged natural respiration. This paper is an analysis of the relationship between ARDs and Deadspace ventilation.

ARDs deplete the capacity of lungs for ventilation. The patients are therefore admitted into the intensive care unit where they require mechanical ventilation (Sundaresan et al 2011, p.1). Through artificial management of ventilation, the mortality of patients suffering from ARDs has been increased. This has been achieved through strictly limiting the tidal volume and the maintenance of plateau pressure (Pplat) below 30cmH₂O. A bronchorial collapse partially or totally excludes certain compartments of the lung from ventilation. ARDS does not respond to administration of high concentration of inspiratory oxygen (Niklason, 2008). Dead space ventilation helps in delivering information about the relationship between body tissue and gas in terms of quantity.

Definition of Terms Relevant to Topic

Dead space ventilation is a form of mechanical ventilation. It is recommended for patients requiring support in elimination of carbon dioxide and in maintenance of oxygen. Ventilated patients usually suffer from abnormalities in the lung structure, obstructions in the airways, and damaged tissues of the lung (Forel et al. 2012).Mechanical ventilation is anchored on the concept that the behavior of air is similar to that of fluid since both air and fluid follow the path that has least resistance as they enter a surface.

The maximal pressure in the airways during respiration is known as Peak Inspiratory Pressure (PIP). PIP is used to measure the pressure in the major air paths in the lungs. Acute or Rapid changes in PIP normally indicate severe complications such as bronchospasm or plugging of mucus. Plateau Pressure (P_plat) on the other hand measures the pressure of airways at the last stages of inspiration and normally indicates the pressure in the alveoli.P_plat determines complications that are brought about by the ventilator such as volutrauma and must always be kept between 30-35 cm H₂O pressure.

The volume of air that is inhaled and exhaled during a respiratory cycle is referred to as tidal volume (Vt). Minute ventilation determines (MV) the levels of carbon dioxide in the blood. “It can be calculated by multiplying the tidal volume with the respiratory rate” (Charron et al., 2011, p.2). Increasing Minute Ventilation decreases the level of carbon dioxide in the blood by increasing the rate at which elimination of carbon dioxide from the blood takes place. Decreasing the M.V increases the level of pulmonary carbon dioxide by reducing the rate at which carbon dioxide is eliminated from the blood. The non-perfused areas in the natural respiratory tract are referred to as Dead Space (V_DS). Dead space describes the parts and components of the respiratory system that do not indulge in elimination of carbon dioxide.

The mean Distribution time (MDT) defines the time available for alveolar diffusion and distribution of tidal gas (Aboab et al., p.1). The ratio of the dead space versus that of the tidal volume determines the lung’s capability to transport carbon dioxide. This process is affected by pathology as well as by settings of the ventilator. When blood perfusion and air ventilation do not match, there is an abnormal deadspace, which manifests itself in the form of disorders such as pulmonary embolism (Bhadade et al. 2011). The condition is characterized by ventilation of the alveolar while blood perfusion is not taking place. An increased VDS/VT ratio causes abnormal oxygenation and irregular ventilation.

The Fraction of Inspired Oxygen (FiO₂) connotes the percentage of oxygen in the air that the ADRS patient inhales. The FiO₂ of room air is 21%. Increase of The Fraction of Inspired Oxygen to levels beyond 60% is attributed to increase in production of free radical oxygen, which could harm the cells due to the toxicity of oxygen. Arterial carbon dioxide (PACO₂₎ decreases because of reduction in ventilation (Charron et al., 2011, p.2). Patients suffering from ARDS have poor respiratory systems and require The Fraction of Inspired Oxygen levels to be above 60% (Forel et al., 2012). High levels of Fraction of Inspired Oxygen are recommended for them even when they are in danger of oxygen toxicity. Mechanical ventilators are used in order to reduce The Fraction of Inspired Oxygen to safe levels.

Dead space ventilation allows the alveoli that do not take part in the ventilation process to expand and increase the surface are available for oxygenation and ventilation. The method is referred to as alveolar recruitment and it is achieved through maximizing the capillaries of the alveolar (Niklason et al., 2008). This way the deadspace alveoli are capable of remaining open and function effectively.

Associated Disease

ADRS is associated with ALI (Acute Lung Injury). This disease is characterized by injury of the lungs due to hypoxemic related disorders (Bhadade et al., 2011). It occurs when sepsis triggers systematic inflammation of the lung. Sepsis is a negative response by the body to a disease or an infection. It is caused by invasion and quick spread of bacteria in the bloodstream. The normal response of the body’s immune system is to fight diseases but on occurrence of sepsis, the immune system becomes agitated and overwhelmed. Primary ALI occurs when the liver is injured directly. For instance, it occurs when a person suffers from an infection of pneumonia. Secondary ALI is normally caused by indirect injury on another organ of the body such as an infection of the pancreas. It is severe but is not as fatal as ADRS.

Clinical/Physiological Effects

It is estimated that one-third of the people who suffer from ARDS end up dying from the disease. The survivors are able to recover the normal functioning of their lungs though most of them contract mild permanent damage of the lungs. During the time that the lungs are not functioning properly, the brain does not receive sufficient oxygen as a consequence brain damage occurs (Forel et al., 2012). ARDS patients therefore suffer from memory loss and a host of other psychological problems.

Current Therapy

Dead space ventilation can take various forms. In Controlled Mechanical Ventilation, the ventilator takes up the complete role of breathing. A rate and volume is set for the ventilator. The patient cannot breathe naturally in this mode because he is completely sedated and almost paralyzed. This mode is not comfortable for the patient and is highly discouraged.

In intermittent mechanical ventilation, the mechanical ventilator is set in such a way that it conveys a certain number of breaths each minute with a regulated tidal volume. The patient has the freedom to breathe in and out without depending on assistance from the ventilator. Pressure is added to the breaths generated by The Intermittent Mandatory Ventilation so that the extra pressure supports the patient when taking own breaths because a lot of energy is expended in inhalation. By increasing the pressure, the workload of breathing is reduced and the patient is able to generate high spontaneous tidal pressure (Bhadade et al., 2011).

The Intermittent Mechanical Ventilator method was traditionally used to wean the patient but modern physicians have stopped its use as it causes tremendous muscle fatigue on a respiratory system that has not fully recovered.

Pressure control ventilation modes are recommended over volume control ventilation modes because they pose less risk of injuring the alveolar. This is because they decrease the level of stretching that the alveolar undergo in weak lungs such as those of people suffering from ARDS (Niklason et al., 2008).The tidal volume is not set but it is achieved through changes in the pressure. Patients are encouraged to breathe spontaneously when pressure is at the highest level.

High-frequency ventilation employs a technique similar to the Airways Pressure Ventilation but small breaths are rapidly delivered to the patient (Aboab et al., 2012). The rapid frequency of delivering breath keeps the alveoli open allowing oxygen to be delivered easily and carbon dioxide to be eliminated without complications. This method requires the patient to be sedated and paralyzed. “In the pressure support method, the ventilator is set to deliver a regulated amount of pressure when the patient initiates natural breath” (Sundaresan et al., 2011).

Positive End Expiratory pressure (PEEP) has been hailed as one of the most important mechanisms in management of ADRS patients. It promotes alveolar recruitment at the termination of expiration by maintaining the unstable units of the lung in an open state (Sundaresan et al., 2011, p.2)

Effects of Therapy

Dead space ventilation mechanisms usually create complications such as volutrauma, hypotension, and in some cases Ventilator Associated Pneumonia. Volutrauma increases the risk of death and multiple organ failure and is associated with high chances of death in the intensive care unit (Forel et al., 2011, p.8). Volutrauma can be avoided by keeping plateau pressures as low as possible. Hypotension is caused by reduced pleural pressure resulting from introduction of positive pressure. It can be reversed by administering fluids and adjusting the ventilator. Ventilator associated pneumonia is a fatal complication that arises from deadspace ventilation. It increases the patient’s mortality, morbidity, and the time-span during which the patient is supported by the ventilator.

Ventilator associated pneumonia is usually treated by use of antibiotics that act on the pathogens that are under suspicion and employment of bronchoscopy mechanisms. The condition can be prevented by shortening the periods during which the patient undergoes mechanical ventilation (Niklason et al., 2008). The patient should also be places in a semi recumbent position as opposed to a supine position.Patients also suffer from deep vein thromboses, decline in nutritional condition and pressure ulcers. Non-invasive ventilation procedures are being called for and they will soon phase out mechanical ventilation procedures. The methods use nose and mouth masks in place of tubes.

Role of the Respiratory Therapist

The respiratory therapist should be actively involved in provision of the appropriate nutrients to patients who have undergone deadspace ventilation. The therapist should design regimens of nutrition that are patient-specific (Bhadade et al., 2011). In addition, they should always ensure that adequate oxygenation is provided, ensure that the hemodynamic function is supported and that the airway is maintained. Perfusion of the ARDS patient must be maximized in the blood capillary system and this can only be done by increasing fluids to ensure that oxygen is readily transported between the pulmonary capillaries and the alveoli. The therapist needs to constantly evaluate the patient’s blood pressure, pulse pressure of the arteries, cardiac index, and the level of the oxygen saturation.

Positioning of the patient is also integral to recovery. The Prone Position (PP) has been advocated for as the most efficient one in critical care. This is because it permits the slow compartments of the lungs that had been excluded from respiration by ADRS to be recruited (Charron et al., 2011, p.2). The therapist should implement kinetic therapy, and the lateral rotational therapy. The therapist should also keep monitoring and evaluating the patient for changes in the respiratory cycle and status such as reduced oxygenation, decreased saturation, increase in the rate of respiration and quick breath sounds (Niklason et al., 2008).

The therapist should also provide dexterous skin care of the patient to avoid pressure ulcers, utilize devices that relieve pressure such as air mattresses, and continuously monitor the patient’s nutrition condition.

Summary

Physicians and respiratory therapists working with ARDS patients undergoing deadspace ventilation should have extensive knowledge of the entire ventilation process so that they are in a position to provide the best medical care. The medication taken by the patient is affected by the mode of deadspace mechanical ventilation that the patient has undergone.

Pharmacologic and ventilation technologies and therapies are evolving rapidly and physicians must be on the lookout for the new regimens and their advantages over traditional approaches. Respiration therapists must always keep in mind that the mode of mechanical ventilation used affects delivery of medication, analgesia, and sedation to the patient. Weaning is very important in shortening the time that the patient spends in the intensive care unit. Non-invasive ventilation involving the use of masks rather than tubes contributes to optimum critical care of an ARDS patient, thus it is highly recommended.

Reference List

Aboab, J. et al. (2012). Dead space and CO2 elimination related to pattern of inspiratory gas delivery in ARDS patients. Critical Care, 16 (R39), 1-8. Web.

Charron, C. et al. (2011). PaCO2 and alveolar dead space are more relevant than PaO2/FiO2 ratio in monitoring the respiratory response to prone position in ARDS patients: a physiological study. Critical Care, 15 (R175), 1-10. Web.

Forel, J. et al. (2012). Ventilator-associated pneumonia and ICU mortality in severe ARDS patients ventilated according to a lung-protective strategy. Critical Care, 16(R65), 1-10. Web.

Sundaresan, A. et al. (2011). Model-based optimal PEEP in mechanically ventilated ARDS patients in the Intensive Care Unit. Biomedical Engineering OnLine, 10(64), 1-18. Web.

Bhadade, R. et al. (2011). Clinical Characteristics and Outcomes of Patients with acute lung Injury and ARDS. Journal of Post Graduate Medicine, 574 (286).

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Introduction

During this millennium, SARS has been identified as the first novel infectious disease. The disease came from Southern China in the late 2002. It is worth noting that the disease has an exceptionally high morbidity and mortality rate.

After originating, the disease affected close to eight thousand people within a period of six months. Approximately eight hundred people died. This emphasizes the need for immediate, relevant, and effective curative and preventive measures.

As a result, there is an imminent threat as far as respiratory medicine is concerned, as well as a challenge regarding the administration and development of antiviral drugs.

The disease is caused by SARS- CoV, a novel SARS- linked coronavirus (Ignatius et al, 2004: 1734). Carlo Urbani reported the first cases of the disease in Vietnam. Later, SARS was reported in China, Germany, USA, and Canada.

Incubation and Infection Period

The approximate incubation period of the disease is 2- 10 d. A 1 d incubation period was reported in three cases in Singapore, and four cases in China. It is not yet established whether the transmission route determines the incubation period.

Until today, there have been no cases of viral transmission before the onset of symptoms. There are no transmissions after the tenth day of fever.

Transmission is more common from critically ill patients, as well as those undergoing through extreme clinical weakening. This happens during the 2^nd week of sickness (Groneberg_, Hilgenfeld & Zabel, 2005: 8).

Efficiency and Route of Transmission

Basically, SARS is not precisely transmissible; approximately four secondary cases arise from primary ones. The infection is rarely transmitted by children. The infectious disease is basically transmitted via respiratory droplets.

This occurs when there is a close contact with a critically ill patient in household and hospital settings. It is worth noting that aerosol generating processes increase transmission of SARS in hospital settings. So far, there have been no reports on transmissions through water, food, vertical, and blood.

The oral- fecal route should not be underestimated, since there are several coronaviruses transmitted via this route (Grinblat et al, 2003: 804).

Signs and Symptoms

The clinical progression of the disease adheres to a typical pattern. The initial stage starts two to seven days subsequent to the incubation, and is similar to a flulike prodrome. It lasts for three to seven days, and has the following features; severe fever, anorexia, malaise, myalgias, chills, headache, and fatigue.

In a number of cases, other characteristics include coryza, sore throat, production of sputum, vomiting, nausea, diarrhoea, and dizziness. The second stage involves characteristics linked to the lower respiratory tract.

These include dyspnea, dry cough, progressive hypoxemia, and respiratory failure, which necessitate mechanical ventilation (Joseph et al, 2003: 2438).

Diagnosis

If an individual is suspected of SARS, initial tests include blood cultures, pulse oximetry, and sputum gram tests (Rentz, 2003: 110).

Treatment, Vaccines and Management

Majority of the patients with SARS develop immunity for the virus, which enables them undergo through the infection. This proves that the hope of developing a secure and effective vaccines.

The options for developing the vaccine are whole killed, live- attenuated, recombinant subunit, recombinant vectored, and epitope- based vaccines (Skowronski et al, 2005: 370).

According to the Centre for Disease Control, proven and suspected SARS patients should be given similar treatments as grave, community- acquired pneumonia.

Moreover, the patient should be isolated and offered serious treatment. Mechanical ventilation should be provided if necessary. Extensive communication with relevant stakeholders should be initiated.

References

Grinblat, L, Shulman, H, Glickman, A, Matukas, L & Narinder, P 2003, “Severe Acute Respiratory Syndrome: Radiographic Review of 40 Probable Cases in Toronto, Canada”, Radiographic Review of SARS, vol. 228 no. 3, pp. 802- 808.

Groneberg_, DA, Hilgenfeld_, R & Zabel, P 2005, “Molecular mechanisms of severe acute respiratory syndrome (SARS)”, Respiratory Research, vol. 6 no. 2, pp. 8.

Ignatius, TS, Yuguo, L, Tze, WW, Wilson, T, Andy, TC, Joseph, HW, Dennis, YC & Tommy, H 2004, “Evidence of Airborne Transmission of the Severe Acute Respiratory Syndrome Virus”, New England Journal of Medicine, vol. 350 no. 3, pp. 1731-1739.

Joseph SM, Kwok, YY, Albert, DM & Klaus, S 2003, “The Severe Acute Respiratory Syndrome”, The New England Journal of Medicine, vol. 349 no. 1, pp. 2431-2441.

Rentz, EJ 2003, “Viral Pathogens and Severe Acute Respiratory Syndrome: Oligodynamic Ag for Direct Immune Intervention”, Journal of Nutritional and Environmental Medicine, vol. 13 no. 2, pp. 109- 118.

Skowronski, DM, Astell, C, Brunham, RC, Low, DE, Petric, M, Roper, RL, Talbot, PJ, Tam, T & Babiuk, SL 2005, “Severe Acute Respiratory Syndrome(SARS): A Year in Review”, Annu. Rev. Med., vol. 56 no. 3, pp. 357–381.