Concepts of Pathophysiology

1. Concepts of Pathophysiology Dr Brenda Johnson

2. Concepts and Components • Models • Definitions

3. Disease and Health Care • 1800’s Infectious disease • 1900’s Public Health • Late 20th century • Age of viruses • Resistant organisms

4. Present Day Problems & Trends • Human genome • Chronic disease • Cardiovascular • Diabetes • Osteoporosis • Alzheimer’s • Cancer • Resurgence of TB/”post-polio syndrome” • Worldwide travel and interspecies infections

5. Definitions • Etiology – Cause of a disease; includes agent as well as intrinsic and extrinsic factors • Genetic • Acquired • Multifactorial • Manifestations – Signs or Symptoms • Sign: an objectively identifiable aberration • Lesion: an identifiable structural change produced during the course of disease • Symptom: subjective feelings in response to a disease process

6. Disease • Etiologic Classification (idiopathic, iatrogenic, metabolic, inherited, neoplastic, immunologic, infectious, etc.) • Pathogenesis – evolution or natural history of a disease • Sequelae – outcome of a disease; usually permanent • Complication – new or separate process secondary to the original disease • Resolution – return to completely normal state without sequelae or complication

7. Concept of Health • “We have become increasingly aware of the importance of preventative measures against noninfectious conditions, especially cancer and coronary heart disease. There is no better way to prevent disease and maintain health than by leading a healthy life, and increasingly, it will be the individual who is responsible for ensuring a healthy passage through life.” • Porth, p. 12 (2005)

8. General Principles of Disease • Trends are more important than isolated, single measurements of a biologic function. • Normal and abnormal processes represent different points on the same continuous spectrum • Disease is dynamic, not static! • The body has a great deal of reserve.

9. Nursing Science • Human responses • Pathophysiologic responses • Experiential responses • Normal physiologic regulatory responses • Behavioral responses

10. Outcomes • How are “best practice models” currently being used in your facility/practice areas? • What types of physiological parameters are used as benchmarks? • What types of symptoms/biophysiological parameters are used as benchmarks?

11. Processes/Symptoms • Pain • Fatigue • Nausea • Dyspnea • Confusion/delirium • Impaired sleep

12. Physiological Processes • Ischemia • Edema • Inflammation • Immune suppression • Muscle atrophy • Stress response • Altered clotting

13. Pain – a human response • Describe the phenomenon of pain from each of the four human response perspectives • Physiologic • Pathophysiologic • Experiential • Behavioral

14. Stress Response Theories • GAS • Neuroendocrine response – catecholamines • Corticotropic response – ACTH and endorphins • Adrenocorticotropic response – cortisol, aldosterone, • Cellular response - cytokines

15. A drop in which two hormones are responsible for anovulation and irregular menstrual cycles in women and decreased testosterone and spermatogenesis in men? (may occur as a result of sepsis or severe trauma?) Explain how emotions (e.g. anxiety or feelings of hopelessness) can be the result of pathological changes in the CNS. CRF (corticotropin releasing factor) and cortisol Immune cells crossing the blood brain barrier in cancer or hormonal changes of menopause can be the cause of hopelessness or mood swings (respectively). Stress/Adaptation & Cause vs. Effect

16. Chaos & Complexity Theory • Complexity and randomness • Simplicity and order • Goldberger (1985) Chaos and health of the CVO system • Fractals • Butterfly effect • “Strange attractors”