The purpose of this assignment is to review pneumonia with reference to clinical and pharmacology concepts related to a patient situation. Thus, it demonstrates how knowledge and evidence are applied in clinical decision-making to deliver quality care to patients.
Pneumonia is the eighth major cause of death in the Unified States with a rate of case casualty approximated between 4% and 10% (Rothberg et al., 2014). The disease can be classified by the conditions under which it is acquired:
- community-acquired pneumonia (CAP),
- hospital-acquired pneumonia (HAP),
- ventilator-associated pneumonia (VAP).
However, the fourth classification was introduced in 2005 by the American Thoracic Society and the Infectious Diseases Society of America (ATS/IDSA) to account for a specific group of patients with latest exposure to the healthcare services systems who are at enhanced danger of harboring multidrug-resistant organisms (MDROs) (Rothberg et al., 2014). Hence, healthcare-associated pneumonia (HCAP) was introduced to account for a poorly explored category of pneumonia, but responsible for a higher mortality rate.
Based on the available evidence, patients recently in contact with the healthcare system have been identified as having increased risk of infection with MDR pathogens (Russo, Falcone, Giuliano, Guastalegname, & Venditti, 2014). However, previous studies and antimicrobial treatment recommended in guidelines for CAP did not account for HCAP. Additionally, majorities of doctors are also not aware of the risk factors associated with the HCAP and the clinical importance of identifying it from CAP.
The most recent data from the Centers for Disease Control and Prevention (CDC) show that pneumonia is the most common healthcare-associated infection (HAI) in the US and significantly affects patient outcomes.
Pathophysiology of Pneumonia and the Implications of the Age Continuum
Pneumonia occurs following the invasion and abundance of pathogenic microbes in the parenchyma of the lung parenchyma, which overpowers the defense system of the host and releases intra-alveolar exudates (Singh, 2012). The advancement and seriousness of pneumonia is a function of various pathogen variables, including virulence and inoculum size, and the host factors.
The presumable microbial responsible for CAP vary, as indicated by various variables, such as differences in the local epidemiology; the clinical setting, such as outpatients, hospitalized, or ICU; seriousness of the conditions; and patient qualities, including sex, age, and comorbidities. Pathogens that are found in the upper airways may gain access to the lower airway systems through microaspiration. In any case, the defense systems of the lungs, both natural and acquired, are responsible for keeping the system sterile and safe.
The progression of pneumonia demonstrates an imperfection in the host’s defense system, exposure to microbes, or an extensive inoculum size. Additionally, weaker immune response, particularly in patients with HIV infection or older patients, or failure in the defense mechanism, for example, caused by active or passive smoking, COPD, or aspiration, usually results in increased weaknesses to respiratory infections in patients.
It has been determined that pathogens responsible for pneumonia, in this case, community-acquired pneumonia can reach the lower respiratory system through four ways. First, pathophysiology of pneumonia involves inhalation, which is the main means through which viral and atypical pneumonia often infect majorities of young healthy patients. It happens through inhalation of infectious aerosol into the airways of vulnerable individuals to start infections. Second, the mechanism involving aspiration oropharyngeal secretions, which are directed to the trachea, the main course for pathogens to the lower airways, is also responsible for CAP. Third, the mechanism also includes hematogenous spread from local infected areas, such as the right-sided endocarditis (Singh, 2012). Finally, the pathophysiology is also noted through direct means via nearby infected foci, for instance, tuberculosis can advance from the lymph nodes to the lung or pericardium, but not always.
Based on the age continuum, high-risk age groups for pneumonia have been identified as children below five years because of low immunity systems, specifically children aged two years or younger, and adults older than 55 to 65 years. In fact, epidemiologic research also shows that increases in inflammation may facilitate the susceptibility to infection among older adults. For example, prolonged inflammation is a risk factor for hospitalization with pneumonia in otherwise healthy older adults (Kale & Yende, 2011).
The Genomic Issues inherent in Pneumonia Process
I t now widely acknowledged that genetic factors and associated changes in DNA are responsible for some cases of pneumonia. In a study assessing restrictive pulmonary disorders, and interstitial lung diseases (ILDs), which are a group of pathologic conditions of the lung, genetic factors have been associated with diverse processes and patterns involving “interstitial inflammation, interstitial fibrosis, and alveolar filling” (Pouladi, Bime, Garcia, & Lussier, 2016, p. 29).
Nonetheless, it is imperative to recognize that when no clear cause is apparent, idiopathic interstitial. ILDs are physiologically seen as restrictive ventilatory and a gas transfer defect (Pouladi et al., 2016). Genetic factors have been suspected to alter the constituents of microbiome found in upper and lower respiratory tracts, and results demonstrate disease advancement in patients with altered upper and lower airways microbiota where possible interactions between a bacterial signature, from within the
Staphylococcus and Streptococcus genera (Pouladi et al., 2016). While progress has been made, more work is expected to advance the understanding concerning the genetic determinants of pneumonia and chromatin modification patterns.
A Review of the Literature on the basics of Pneumonia and its Treatment
Pneumonia is described as an intense lower respiratory tract infection. All individuals can get pneumonia, but children and elderly individuals are more prone to this infection. Diagnosis of pneumonia is based on the clinical manifestations of symptoms, such as fever, pleuritic chest pain, focal chest signs, shortness of breath, cough, secretion of sputum, night sweats and rigors, and elevated rate of respiration. These aspects of physical examination are the basic approaches to determining the presence of pneumonia.
For cases of viral pneumonia, if otherwise not serious, patients are advised to rest. However, a diagnosis that reveals bacterial pneumonia results in the administration of antibiotics within four hours following admission to a care facility. Severe cases require bilevel positive airway pressure (BiPAP), continuous positive airway pressure (CPAP), or be intubated. Additionally, patients may also be given fluid to facilitate secretions. Other treatment approaches include rest, avoidance of cough medicine and aspirin in the case of children, fever management. Flu shot is the known option for prevention of pneumonia, especially among individuals who are high risks.
Numerous laboratory diagnosis types have been developed to diagnose pneumonia, and it is observed that microbiological diagnosis of the condition is an essential key element for a good clinical outcome, it is imperative to follow national and international guidelines (Cilloniz, Martin-Loeches, Garcia-Vidal, Jose, & Torres, 2016). Tests, such as serology tests, have been applied when pathogens are alleged based on the epidemiological data. In addition, serology for intracellular pathogens and flu test during the flu season are also used.
Based on the CAP guidelines, a discretionary microbiological diagnostic test in low to mild instances of CAP is preferred, and in exceptional circumstances, it ought to be chosen. For of a serious CAP condition, it is necessary to use blood cultures, sputum staining, sputum culture, and the urinary antigen test for Legionella and pneumococcus (Cilloniz et al., 2016). Notably, microbiological diagnosis of CAP is generally being driven by respiratory samples or blood culture (Cilloniz et al., 2016). The principle issues with these traditional strategies are the low yield and long turnaround time noted in the range of 48 hours to 72 hours, and the way that past antibiotic utilize influences microbiological results.
Diagnostic testing for pneumonia is also available. The most known microbiological diagnosis of blood and pleural culture is still applicable. In this case, it involves conducting blood cultures in patients prior to a past antimicrobial treatment, which has a high specificity yet a low positivity (under 20% of the cases). Pneumococcus is the primary causative agent in blood cultures of patients diagnosed with CAP.
Favorable outcomes of blood cultures in patients with HAP range from 8% to 20%. It is also necessary to point that the role of blood cultures in the diagnosis of VAP is restricted in light of the fact that the spread of the contamination to the blood happens in less than ten percent of the cases.
In roughly 40% of CAP cases, pleural effusion is available (Cilloniz et al., 2016). Thoracentesis is required in such conditions because empyema is viewed as a risk factor for poor results. Further, pneumococcal antigen availability, or even molecular availability are preferred in pleural fluid specimens.
Some findings demonstrate the need to evaluate six variables. These factors include liver disease, pleuritic pain, tachycardia, tachypnea, systolic hypotension, and absence of prior antibiotic treatment in order to predict bacteremia in CAP patients (Cilloniz et al., 2016). Hence, it is important to consider all the six factors during diagnosis.
The diagnosis also involves sputum stain and culture. The sputum test is conducted prior to patients start an antimicrobial treatment. For enhanced microbiological diagnostic precision, a satisfactory sample and transport of the specimen is suggested, and a great quality sample is necessary when the sputum specimen has fewer than 10 epithelial cells and over 25 lymphocyte cells (Cilloniz et al., 2016). Further, a plausible analysis may be applied when a pathogen is not a part of the sputum culture, particular in children under 2 years of age and patients with chronic pulmonary infections oftentimes where oropharynx colonization by pneumococci is always present.
Endotracheal suction is what might as well be seen as sputum test in VAP patients and both specimens have similar approaches to quality evaluations. To recognize colonization from the disease, a limit of more than 105 colony creating units/mL is recommended in VAP patients (Cilloniz et al., 2016).
According to Noguchi et al. (2015), the causative pathogens of HCAP are still controversial, and the application of normal samples of sputum cultivation is sometimes not suitable because of the possible contamination with oral bacteria. It is likewise at times hard to decide if methicillin-resistant Staphylococcus aureus (MRSA) is an actual causative pathogen of HCAP (Noguchi et al., 2015).
From the findings of Noguchi et al. (2015), it was determined that HCAP patients had heterogeneous bacteria and high incidence of streptococci relative to that observed using cultivation techniques. Moreover, the findings of the study showed a lower rate of MRSA than already expected in HCAP patients.
Some findings suggest that HCAP is a false concept derived from low-quality evidence (Chalmers, Rother, Salih, & Ewig, 2014). Chalmers et al. (2014) conducted a systematic review and meta-analysis and determined that the healthcare-associated pneumonia classification depended on low-quality evidence reinforced by bias and did not precisely indicate antibiotic-resistant pathogens. The concept of HCAP was initially proposed in the 2005 in the guidelines (Rothberg et al., 2014; Chalmers et al., 2014).
It was presented as pneumonia noted in nursing home areas, patients hospitalized for at least 2 days in the past three months, patients getting home infusion interventions or wound care, and patients visiting a hemodialysis care facility in the past 30 days (Chalmers et al., 2014). The categorization of HCAP depended on the thinking that patients with successive healthcare contacts would at first need a wide range of anti-microbial treatments since they would be at higher risk for resistant pathogens (and thus higher death rates) relative to patients with no such contacts.
In any case, HCAP has been uncertain, with a few specialists scrutinizing the quality of the findings while others have noted that the HCAP concept fluctuates based on the location. Subsequently, in light of these controversies, Chalmers et al. (2014) tried to demonstrate how precisely HCAP classifies patients with resistant pathogens, to assess the nature of the HCAP research findings and their potential for bias, and to approve or invalidate the HCAP categorization.
Databases for Literature
Literature for the review was obtained from different databases using specific keywords: pneumonia, pathophysiology, age continuum, clinical manifestation, genomic issues, diagnosis, treatment, and follow-up. Databases utilized for data collection included PubMed, BMJ, CDC, and IDSA/ATS. Notably, only literature less than seven years were chosen. All studies used in this study were peer reviewed. For this study, no electronic clinical tools were utilized.
Published Clinical Guidelines related to the Pneumonia Process
The latest clinical guidelines published by recognized organizations were considered for the pneumonia process. The guideline for CAP was published in 2004. These guidelines included “Infectious Diseases Society of America/American Thoracic Society Consensus Guidelines on the Management of Community-Acquired Pneumonia in Adults” and “Health Care—Associated Pneumonia (HCAP): A Critical Appraisal to Improve Identification, Management, and Outcomes—Proceedings of the HCAP Summit”.
The Approach to the Treatment of Pneumonia
The selected treatment is empirical antimicrobial therapy. Treatment approaches are based on a class of antibiotics instead of a distinct drug. A single drug is only preferred when evidence provides strong support. Otherwise, many classes of antibiotics have demonstrated better overall efficacy, particularly when antibiotics that are more potent are administered because they curtain opportunities for drug resistance. These antibiotics include amoxicillin, clarithromycin, and doxycycline. Majorities of clinical regions will have specific local treatment plans for antibiotic treatment, and these adopted to assist in lessening the risk of resistance from pathogens. This approach is especially critical in patients with hospital-acquired pneumonia.
It is imperative to recognize that antibiotic recommendations differ for the four classifications of pneumonia, as well as the site of care deliver. For instance, CAP interventions must consider whether the place of care is intensive care unit (ICU) or non-ICU to determine the most appropriate therapies. Majorities of hospitalized CAP patients are at first treated with an intravenous regimen, but the treatment may changes especially for patients without risk factors for extreme pneumonia.
Such patients may receive oral treatment, particularly with highly bioavailable agents. Still, patients with CAP are at first treated with empiric antibiotic treatment when hospitalized. Once the etiology of CAP has been determined based on sufficient microbiologic techniques and no laboratory or epidemiologic evidence suggests coinfection, then it is appropriate to target the specific causative pathogen.
Other treatment approaches generally depend on other patient-specific factors. For instance, CAP patients with sustained septic shock require drotrecogin alfa administered within 24 hours following admission while patients with hypotensive require occult adrenal insufficiency screening.
Oxygen treatment is a primary part of treatment therapies for all patients with pneumonia, including children and adults (Wu et al., 2017). The objective of this therapy is to keep up saturation over 93%. Oxygen treatment could differ from low concentration to high concentration stream delivered through a trauma or non-rebreather mask.
Although pulse oximetry has a part to play in checking patients with pneumonia, it can give inaccurate and arterial vessel gas investigation ought to be performed to guarantee adequate oxygenation is delivered to patients (Langley & Cunningham, 2017). For patients who consistently experience hypoxic in spite of receiving high stream oxygen, the utilization of continuous positive airway pressure (CPAP) is supported as a practical treatment choice. As such, some patients may require a transfer to a high-dependency unit, and local processes must be followed.
Any indications of dehydration and hypotension ought to be treated as appropriately as possible. Patients should have intravenous (IV) and the IV liquids ought to be administered to rehydrate patients because great hydration makes it simpler for patients to expectorate any discharges.
Patients’ nutrition intervention should also be considered. Numerous patients with serious pneumonia will suffer nausea, leading to a loss of appetite. Nonetheless, their calorific requirement is elevated due to the presence of infection. Prior recommendation from the dietetics department should be available to ensure that patient the patient’s calorie intake is sufficient to support the body to manage the disease.
Pain management (analgesia) is a vital part of intervention for pneumonia (McNamara, Best, & Heather, 2012). In most instances, patients may suffer pleuritic-related chest pain and if this is not controlled effectively, it might restrain optimal lung activities during inspiration and subsequently worsen condition of patients. It is recommended that patients who have experienced respiratory failure should have ventilatory support.
Non- invasive ventilation could offer adequate support to patients whose conditions are not sufficiently serious to want admission to ICU. Once more, treatment efforts should also focus on the engagement of anesthetic staff to encourage a seamless transfer of patients to ICU when optimal ventilation is necessary. Hospitals should have clear guidelines to ensure referrals are done well, for example, using the emergency department to facilitate referrals.
Immunization is also recommended for patients with CAP to prevent potential for flu and pneumococcal infections. Screening for flu vaccination status is justified, particularly during a flu season in all patients. Additionally, screening for pneumococcal immunization status is justified in patients aged 65 or more or patients who may have other requirements for vaccination. Smoking cessation is also mandatory for hospitalized pneumonia patients, particular in CAP patients.
Although treatments are based on the ATS/IDSA guidelines, some results show that therapies may not be effective. The case of HCAP is different because of conflict results. According to Rothberg et al. (2014), HCAP patients had results that were more serious than results obtained for CAP patients, even after controlling for comorbidities and demonstrating seriousness of condition, in spite of the fact that the variation looked less as other findings have shown. Further, recent findings have failed to show enhanced results when guideline-concordant (GC) antibiotics are given to patients with HCAP (Attridge et al., 2016).
The study by Attridge et al. (2016) was intended to assess the relation between patient outcomes and GC treatment in patients admitted to an intensive care unit (ICU) with HCAP. The study focus was 30-day patient mortality, and risk factors for the major result were evaluated and the findings did not show enhanced outcomes in ICU patients with HCAP who received GC-HCAP treatment (Attridge et al., 2016).
HCAP was based on the 2005 ATS/IDSA guidelines, which recommended an extended-spectrum antibiotic treatment for patients meeting HCAP criteria (Webb, Dascomb, Stenehjem, & Dean, 2015). In any case, the prescient value of the HCAP model is constrained, and evidence shows that outcomes are not enhanced following the use of HCAP guideline-concordant treatment and, thus, improved techniques to anticipate risk of CAP are required (Webb et al., 2015). Further improvement and validation of prediction scores derived from risk factors that are more thorough for CAP are required. Once a precise, satisfactorily certified prediction score is provided, its clinical importance will be assessed.
Additionally, it is also important to recognize that care providers may not always adhere to the requirements of the guidelines. For instance, the IDSA guidelines recommend treating patients with CAP for five days and patients with HCAP for eight days in less complicated cases, but Madaras-Kelly et al. (2016) show that majorities of pneumonia patients still get improperly prolonged therapies. Although the guidelines allow for some forms of antibiotic treatment extensions for the duration of pneumonia (additional of three days), some care providers extend treatments with as many as eight days for less severe CAP and 11 days for less severe HCAP even for pneumonia patients who have attained a clinical stability status.
This practice is done outside the optimal recommendations. Notably, oral therapies recommended after the discharge of patients are also responsible for extend unwarranted use of antibiotics. Thus, managing care transition is vital for care providers to follow guideline-concordant pneumonia care to eliminate unnecessary use of antibiotics. It implies that care provided still lag behind the requirements of the guidelines.
Defense of the Choice of the Treatment Option
Empirical antimicrobial therapy is the preferred choice for pneumonia treatment because it is based on the guideline-concordant pneumonia care. Many initial treatment regimens for pneumonia-hospitalized patients are empiric, particularly in the case of CAP and HCAP (Russo et al., 2014). A small number of pathogens are in responsible for the greater part of pneumonia infections, and the most commonly identified microbe is Streptococcus pneumonia, as well as other types, including Haemophilus influenzae, the atypical microscopic organisms, such as Mycoplasma pneumoniae, Chlamydia pneumoniae, and Legionella spp), oropharyngeal aerobes and anaerobes.
It is imperative to initiate antibiotic treatments immediately once the types of pathogen s have been identified and pneumonia classified into the right category, such as CAP, HCAP, HAP, or VAP. Irrespective of the use application of empiric treatment in clinical or epidemiologic settings, testing for a microbial analysis is essential in clinical or epidemiologic settings, recommending a potential infection with microbes that need interventions not the same as regular empiric regimens. These microbes may include Legionella species, flu, avian flu, Middle East respiratory syndrome coronavirus, and community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) among others.
It is also important to recognize the rising cases of drug resistant S. pneumoniae (DRSP), methicillin-resistant S. aureus, methicillin-resistant Staphylococcus aureus (MRSA), or P. aeruginosa (Shorr & Zilberberg, 2015), which render the use of empiric therapy almost irrelevant. Intervention failures have been shown with utilization of macrolides for macrolide-resistant microbes.
Pneumonia patients who do not need ICU admission should consider a combination of therapy pathogens. Patients may also consider monotherapy if they are unable to use macrolide. It is imperative of care providers to define the scope of medications involving microbes, such as MRSA or Pseudomonas to understand their risk levels. In such instances, alternative medications should be provided.
Risk factors for the increment of pneumonia and the rise of pneumonia from medication-resistant microbes, mainly methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, are not similar among the category of patients with HCAP or CAP. For instance, dialysis patients face different risks compared to nursing home patients (Shorr & Zilberberg, 2015). Besides, there is relevance heterogeneity of risk factors for pneumonia within the HCAP subgroups, for example, because of differences in local factors, for example, local microbiology and strategies for providing care and differences in individual risk components, for example, status or earlier antibiotic contacts.
Additionally, it is imperative to evaluate evidence for other causes of pneumonia, such as potential risk factors for cases of pneumonia drug resistance. Thus, the therapy should always focus on patients at greater risk for HCAP. Still, within the scope of pneumonia infections, care providers should always ensure that they account for different types of pneumonia based on types of risk, including MRSA and possible resistance to drugs.
Researchers have developed different risk scoring devices to categorize patients based on the probability that their infection has emanated from pathogen, for example, methicillin-resistant S. aureus or P. aeruginosa (Shorr & Zilberberg, 2015). Results from the scoring tools give accurate means to isolate patients on the premise of the possible recuperation from resistant microbes than does the HCAP infection.
A Plan for Follow-up and Referral
Follow-up is done after 48 hours following treatment to determine responses to antibiotics. Physicians should ensure that patients comprehend their conditions, treatment, and follow-up. Any referrals to physicians should be based on the results of the laboratory tests and X-ray results. Patients are also referred to physicians within 48 hours if they fail to respond to therapies. Referrals also should focus on unresolved pneumonia and other underlying problems beyond the scope of nurse practitioners.
Regular follow-up is not necessary for patients with chest radiographs for who are responding clinically well within the initial week of treatment. Nonetheless, it is imperative to conduct further chest radiographs between 7 to 12 weeks following interventions for patients aged 50 years and over to determine the resolution of the condition and eliminate any underlying infections. A follow-up is particularly imperative for male pneumonia patients who are also smokers within this age group.
The most widely recognized reason for treatment failure is the absence of a response by the host regardless of a proper antibiotic therapy. In this case, it is imperative to explore other possible risk factors for therapy fairly, such as aspiration pneumonia, neurologic illness, multilobar pneumonia, MRSA infections, Legionella, or gram-negative bacilli, risk factor score index, antibiotic resistant microbe, and any other existing conditions (Liantonio, Salzman, & Snyderman, 2014; Corrao et al., 2014).
Conclusion
Pneumonia is the leading killer among healthcare-associated infections. It also contributes significantly to the burden of care, particularly in senior citizens and children. As such, some organizations have developed guidelines to help clinicians to deliver the most appropriate therapies and realistic clinical course and outcomes. However, HCAP has been controversial with regard to classification and guidelines’ antibiotic therapy recommendations. Nonetheless, treatments for all to categories of pneumonia should rely on the guidelines, and clinicians are encouraged to follow recommendations. Meanwhile, it is also imperative to improve the quality of care based on emerging evidence, particularly for MRSA and other underlying symptoms.
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