Health alt. concept, scope, common terms of pathophysiology PDF

Preview

Summary

health alterations concept, scope, common terms of pathophysiology ...

Description

Concept, Scope, and Common Terms of Pathophysiology Understanding health and disease is integral to providing quality and effective health care for patients. A deeper look and analysis into the causative factors for disease allows health care professionals to answer questions about why patients get sick, and how their diseases or disorders can be treated and managed. Focusing on the body, the study of pathophysiology uncovers many questions related to how certain diseases form, the ways in which they manifest, and the reasons they affect us physically. This journey into the study of pathophysiology begins with understanding the terms and concepts that apply to disease states, the progression of diseases, and the occurrence of diseases.

What Is Pathophysiology? Pathophysiology is the study of the physiological, or functional, changes in the body that result from a disease. The term pathophysiology combines two important disciplines used in health and medicine: pathology, which is the medical discipline that focuses on the diagnosis of disease, and physiology, which is the discipline concerned with how the body functions. Pathophysiology begins with understanding the terms and concepts that apply to disease states, the progression of diseases, and the occurrence of diseases. A strong background in anatomy and physiology, especially normal function and terminology, is essential because diseases affect multiple organs and systems. The significance of these effects on organs and body systems can be better understood with a firm foundation of normal physiology, so that knowledge can be applied to the altered physiological functions. Diseases and abnormal conditions cause changes at microscopic and cellular levels. Pathophysiology focuses on diseases and abnormal conditions that usually involve changes at the organ or system level. It is essential to understand cellular changes, because it helps build a stronger foundation in understanding the full, systemic effects of a disease state.

State of Health and Homeostasis Studying pathophysiology requires an understanding of states of health and homeostasis.

State of Health The World Health Organization (WHO) includes physical, mental, and social well-being in its definition of health. However, quantifying and defining a state of health is based on so many factors, that it is difficult to do. People have many genetic differences, as well as different life experiences and environmental influences, which create a variable base. Defining a state of health also depends on the context in which health is measured: A person who is blind can be in good general health. A person who is injured may experience a temporary impairment to a specific body part, but the individual’s overall health is not altered.  A person who has diabetes and is experiencing economic difficulty may be in poor health, physically and socially.  

Homeostasis Homeostasis is the maintenance of a stable environment within the body that is not affected by external changes or factors. Disease develops when significant changes occur inside the body. These changes lead to a state where homeostasis can no longer be maintained without intervention. In normal conditions, the body knows how to reset itself to achieve homeostasis, or a balance. As frequent minor changes occur in the body, the compensation mechanisms respond. This allows homeostasis to be quickly restored. Usually the individual is not aware of these changes or the compensation taking place.

Normal Limits for Health Indicators Normal limits help health care professionals better understand the ranges of health, while deviations identify the onset of diseases. Normal limits can be used to help establish states of health or illness pertaining to blood pressure, pulse, and temperature. When defining “normal” limits for health indicators, the values used usually represent an average or a small range. These values represent what is expected in a typical individual, but are not an absolute criterion. It is also important to note that normal limits can change for healthy individuals depending on things like age, gender, environment, and activity level. For example, well-trained athletes have a slower resting heart rate than other healthy individuals, so their normal limits are adapted to take their activity level and individual health status into consideration. Also, the body experiences small daily fluctuations in blood pressure as the body responds to minor changes in activity, body position, and stress. Due to the many variables and fluctuations, it is essential to consider the total assessment of the individual to gain a better understanding of that person’s state of health.

Disease and the Disease Process A disease is defined as a deviation from the normal limits, structure, or function of any part of the body. Diseases develop when significant changes occur in the body and homeostasis is interrupted and cannot be restored without intervention. Diseases can advance or spread as part of a disease process, affecting more body systems or organs as the disease advances. Therefore, diagnosing diseases early on can lead to more favorable outcomes.

Diseases need to be diagnosed. Diagnosis is the identification and classification of a specific disease. There are many ways to diagnose diseases.  Health professionals arrive at diagnoses by evaluating or observing a patient, conducting laboratory tests, or conducting other types of diagnostic tests, such as x-rays or MRIs. Verifying a diagnosis usually involves more than one factor. For instance, a diagnosis of cancer could not be confirmed by a blood test with high white blood cell count alone. The patient would likely be sent for imaging tests to see whether there is the presence of any tumors followed by a biopsy. Therefore, a combination of tests is often used for diagnosing diseases.  Pathology laboratory studies are also useful in establishing the cause or diagnosis of a disease. Pathologists examine tissue specimens from biopsy procedures (excision of very small amounts of living tissue), surgical specimens, or examination after death (autopsy) to help diagnose diseases. Analysis of body fluids is another essential diagnostic tool in a pathology laboratory.

Scope of Pathophysiology and Evidence-Based Practice Pathophysiology examines the changes in normal structure and function of the body. Many disorders that affect a particular organ or body system will display a set of clinical manifestations, known as signs and symptoms. It is important to note that many diseases can look like each other, or manifest in similar ways. For instance, inflammation in the kidney causes pain because of the swelling of the tissue, but an infection of the kidneys results in pain, as well. Diseases cannot be diagnosed on clinical manifestations alone. Therefore, a firm understanding of disease processes, and the cause and effect

relationship of pathophysiology, is necessary for identifying and diagnosing diseases. Diseases are complex and not always easy to detect or diagnose. Studying pathophysiology requires an awareness of the difficulties involved in diagnosing and treating diseases. Thanks to technological advances, sophisticated and expensive diagnostic tests are now available to help health care professionals better identify diseases when they appear, as well as take a deeper look into the body for more precise treatment. However, not all individuals have access to these comprehensive tests. The availability of these tests depends on the geographic location and access to large, wellequipped medical facilities. Additionally, a long waiting period may be necessary before testing and treatment can be available in resource-poor areas. Pathophysiology depends on the use of evidence-based practice (EBP). Evidence-based practice is the act of using the most current and best evidence, data, or information for making decisions about patient care. EBP is founded in research, trials, clinical guidelines, medical publications, and other credible resources that are meant to help health care professionals around the world apply high quality standards and findings to their practice. When making decisions about patient treatment and care, health care professionals call on EBP to complement their other array of diagnostic procedures. This helps ensure patients are getting a comprehensive analysis and scope of care for disease management.

Why Study Pathophysiology? The study of pathophysiology is important because:  Pathophysiology focuses on major diseases, but other, lesser known disorders can be included in pathophysiology, too. This helps provide more exposure to a broader range of diseases. The information and principles that are obtained by studying the major diseases can then be applied to other conditions or disorders that are encountered in practice.

 People become ill with new diseases every day, in all parts of the world. Studying pathophysiology is important for helping to manage or prevent diseases, and understand why diseases are caused. Some diseases have unknown causes; other diseases are being spread rapidly among people and geographic locations. Studying pathophysiology allows for better understanding of these diseases, their causes, and treatment potential. From this information, new drugs and vaccines can be formulated, new medical equipment can be developed to help target and combat specific diseases, and health organizations can keep the public informed to help prevent diseases.  Extensive research projects are performed to try and prevent, control, or cure many disorders. For example, through pathophysiological research, it was learned that most cases of cervical cancer resulted from human papillomavirus (HPV) infection. Once this information was detected, a vaccine was developed to protect men and women against the most common strains of HPV. Clinical trials showed that the vaccine helped reduce the number of women who developed cervical cancer. Now, this vaccine is available to young women to prevent cervical cancer in later years. Although it does not provide 100% guaranteed protection, the vaccine is known to help reduce the likelihood of cervical cancer. This is just one example of the importance of studying pathophysiology.

Research and Development in the Field of Pathophysiology It is important for students and health care professionals to have the most current and reliable information to apply for better patient care. Studying pathophysiology involves continually checking new information; using reliable and accurate resources, such as professional organization websites, and scholarly and peer-reviewed journals; and attending seminars, conferences, and continuing education series.

New medical information is being constantly discovered, and changes in health care trends, technology, vaccinations, and drug formulations can help manage or prevent diseases. For example, wearable technology is being developed to help patients detect heart attacks or seizures before they begin; wearable technology or implantable technology is being created to help measure and monitor blood glucose levels in patients who have diabetes, which can then trigger the release of insulin to meet the patient’s needs. Organizations like the World Health Organization (WHO), United States Public Health Service, the Centers for Disease Control and Prevention (CDC), and state and local authorities, as well as agencies in countries around the world, gather reports and data that are organized and published for health care professionals to access and apply in practice. Such data often leads to new research efforts, allows for tracking new or fatal diseases, or provides warnings about current treatments that should be ceased due to adverse reactions. Those who work in health care are responsible for staying aware of the deviations from the expected outcomes, and must keep up with the new discoveries. Although it may sometimes feel like information overload, this is a critical part of professional practice.

Describing Etiology Etiology is the study or science of the causative factors of diseases. Diseases can have a single causative factor, or several causative factors. Etiology examines the many variables and reasons for why diseases occur. Within the study of etiology are etiologic agents. Etiologic agents are divided into the following categories:        

Congenital defects Inherited or genetic disorders Microorganisms, such as bacteria or viruses Immunologic dysfunction Metabolic derangements Degenerative changes Malignancy Burns and other trauma

 Environmental factors  Nutritional deficiencies There are different ways to describe the causes of diseases.  Idiopathic is a term used when the cause of a disease is unknown.  Iatrogenic is a term used to describe when a treatment, procedure, or medical error causes a disease. An example of this is of a patient going through chemotherapy to treat cancer but experiencing secondary complications, such as infections or weakened immune system, caused by the chemotherapy.

Predisposing Factors and Other Causes of Disease The study of etiology requires an analysis of predisposing factors and other causes of disease. Predisposing factors indicate whether or not a person is at risk for contracting a disease. They are not guarantees that a disease will develop, but they can provide more information about the likelihood of a person getting a disease or disorder. Examples of predisposing factors are described in the table. Predisposing factors

Examples

Age

Older individuals are more susceptible to developing dementia. Women have a higher risk of getting osteoporosis than men. If a parent has cardiovascular disease, this predisposes the child to cardiovascular disease, too. Exposure to asbestos in the work environment can increase the risk of cancer.

Gender Inherited factors Occupational exposure Dietary and behavioral practices

An insufficient intake of calcium predisposes an individual to the development of osteoporosis. Smoking and sedentary lifestyle are factors that can

Predisposing factors

Examples

increase the risk of heart attack.

Some predisposing factors, such as age, gender, and inherited factors, cannot be changed (non-modifiable). However, other predisposing factors can be reduced by modifying behaviors (modifiable). Understanding predisposing factors allow health care professionals to educate patients on limiting modifiable predisposing (risk) factors.

Prevention and Prophylaxis When health care professionals understand more about the etiology of diseases, they can promote prevention and prophylaxis with their patients.

Prevention of diseases Prevention involves taking steps to actively mitigate or lessen the risk of disease, or exposure to predisposing factors. Examples of prevention methods include: Vaccinations against certain disease strains Modifying diet and nutrition Exercising and leading a more active (and less sedentary) lifestyle Removing harmful materials in home, work, and community environments  Stopping harmful habits, such as substance use and smoking    

Patient assessments can often tell nurses and other health professionals whether or not a patient has predisposing factors that can be prevented. It is important to teach patients how to make better, healthier decisions about their health.

Prophylaxis measures for diseases Prophylactic measures are created to help individuals preserve their health and stop the spread of diseases. In a way, this is similar to prevention, but prophylaxis also focuses on maintaining good health. For example, taking a baby aspirin daily is a prophylactic treatment for patients who are at a high risk of having myocardial infarctions.

Terms Related to Progression of Disease There are many terms used in the health industry that describe the progression of a disease. It is important to have a firm understanding of these terms to provide optimal care to patients. Term

Definition

Pathogenesis The development of the disease or the sequence of events involved in the tissue changes related to the specific disease process Onset The way in which a disease forms Ways to classify the onset of a disease:  Sudden/Acute  Insidious – a gradual progression with mild or vague signs and symptoms Acute

Chronic Subclinical

A short-term illness that develops quickly with obvious signs and symptoms, such as appendicitis and its associated right lower quadrant pain A condition that develops gradually and persists for a long time, such as rheumatoid arthritis A state in which pathologic changes occur, but the patient does not exhibit any obvious manifestations, such as kidney damage, which can progress to an advanced stage of renal failure before the patient shows any symptoms

Term

Definition

Latent A stage of a disease in which no clinical signs are presenting (also called the silent stage or the incubation period) Can last for a day or several weeks Is a dangerous period because certain diseases can still be communicable during this stage, even though no symptoms or signs are evident Prodromal The early development of a disease when the patient notices a change in the body, but the signs or symptoms are nonspecific, such as:  Fatigue  Headache  Loss of appetite Results in negative lab tests, so it is difficult to confirm a diagnosis during the prodromal period

Terms Related to Manifestation and Treatment The manifestation of a disease is a critical point in a patient’s life; one that nurses and health professionals must pay attention to and understand to treat the patient appropriately and effectively. How a disease manifests is critical to the course and treatment of the disease. Manifestations of Diseases Manifestations are the clinical evidence or effects of the disease. These are also called the signs and symptoms.  Distinguishing between signs and symptoms: It is important to distinguish between signs and symptoms. Signs are objective indicators of 

disease. These are measurable or quantifiable, and they are obvious to others either by observation or lab analysis. Examples of signs of disease include fever, rash, or limping. Symptoms are subjective feelings that the patient experiences. Symptoms cannot be measured or observed from the outside or from lab results. Examples of symptoms include pain or nausea.  Manifestations can be local or systemic. Local means the manifestation is found at the site of the problem. An example of a local manifestation is redness and swelling on the skin. Systemic means the manifestations are general indicators of illness. A fever is an example of a systemic manifestation. A lesion is a local change in tissue. An example of a lesion is a blister or a pimple on the skin or lung lesion found in lung cancer. Lesions are manifestations of diseases.  A syndrome is a collection of signs and symptoms that affects more than one organ. These signs and symptoms usually occur together in response to a certain condition. Course and Treatment of Disease 

 

 

The progress of a disease can be marked by remissions (the signs and symptoms of a disease subside) and exacerbations (the signs and symptoms of a disease increase). Disease progression can also be marked by a precipitating factor, which is a condition that triggers an acute episode related to the disease. For example, if a patient has asthma, the precipitating factor would be a particular allergen. Complications are additional problems that arise after the onset of the disease. These are secondary to the disease. An example of a complication is when a patient develops congestive heart failure after a heart attack. Therapy or therapeutic interventions are treatment measures. They are used to promote recovery or slow the progression of a disease. Examples of therapy include surgery, ...