NUR 631 TOPIC 3 DQ 1 • Online Nursing Essays

Sample Answer for NUR 631 TOPIC 3 DQ 1 Included After Question

Select two of the following discussion questions for your discussion response. Indicate which questions you have chosen using the format displayed in the “Discussion Forum Sample.” 

Explain how acid-base physiology leads to the regulation of fluid balance and extra cellular pH. 

What is the equation for the carbonic acid/bicarbonate buffering system? How do actions at the lungs and kidneys affect this equation and thus compensate for alterations in plasma pH levels? 

How do changes in plasma osmolality affect the physiology of erythrocytes? 

A Sample Answer For the Assignment: NUR 631 TOPIC 3 DQ 1

Title: NUR 631 TOPIC 3 DQ 1

Acid-base homeostasis and pH regulation are critical for both normal physiology and cell metabolism and function. (McCance et al., 2018b). Every organ system of the human body relies on pH balance; however, the renal system and the pulmonary system are the two main modulators (McCance et al., 2018b). The pulmonary system adjusts pH using carbon dioxide; upon expiration, carbon dioxide is projected into the environment (McCance et al., 2018b). Due to carbon dioxide forming carbonic acid in the body when combining with water, the amount of carbon dioxide expired can cause pH to increase or decrease (McCance et al., 2018b). It is well documented that extracelluar fluid  pH remains between 7.35 and 7.45 and thus it is a major requirement of our metabolic systems to ensure that hydrogen ion concentrations are maintained between 0.035 and 0.045 mEq (Bournot et al., 2022). The acid-base balance of the body refers to the ideal pH of body fluids, which is determined by the hydrogen ion (H+) concentration of body fluids. (Bournot et al., 2022). 

The bicarbonate buffer system is an acid-base homeostatic mechanism involving the balance of carbonic acid, bicarbonate ion, and carbon dioxide in order to maintain pH in the blood and duodenum among other tissues, to support proper metabolic function : CO2 + H2O –> <– HCO3(-) + H(+) (Bournot et al., 2022). The kidneys excrete additional hydrogen ions (acid) in the urine and retain bicarbonate (base) (Bournot et al., 2022) . Conversely, when the pH is too high (i.e., during alkalosis), the respiratory rate decreases to retain acid in the form of CO2 (Bournot et al., 2022). The kidneys excrete bicarbonate (base) in the urine and retain hydrogen ions (acid) (Bournot et al., 2022). 

Plasma sodium concentration is normally held within a narrow range (Reinhart et al., 2015). It may, however, vary greatly under pathophysiological conditions (Reinhart et al., 2015). Changes in osmolality lead to either swelling or shrinkage of red blood cells (RBCs) (Reinhart et al., 2015). 

Bournot, A., Lanham-New, S. A., Alghamdi, M., & Jalal, J. (2022). Nutritional aspects of bone. In Elsevier eBooks. https://doi.org/10.1016/b978-0-12-821848-8.00189-x 

McCance, K. L., Huether, S. E., & Rote, N. S. (2018b). Pathophysiology: The Biologic Basis for Disease in Adults and Children. Mosby. 

Reinhart, W. H., Piety, N. Z., Goede, J. S., & Shevkoplyas, S. S. (2015). Effect of osmolality on erythrocyte rheology and perfusion of an artificial microvascular network. Microvascular Research, 98, 102–107. https://doi.org/10.1016/j.mvr.2015.01.010 

1. Explain how acid-base physiology regulates fluid balance and extracellular ph. 

The body uses a variety of physiological adjustments to keep things in homeostatic balance. Maintaining the proper acid-base balance is one of them. The normal pH of the human body is between 7.35 and 7.45, with an average of 7.40. This is the case when no pathogenic conditions are present. The oxygenation of the blood, an essential biological activity, functions best at this pH. ( Hopkins et al., 2022). 

 Cellular metabolism produces acids as waste products. Metabolic acidosis, metabolic alkalosis, respiratory acidosis, and respiratory alkalosis are humans’ four most common acid-based illnesses. Compatibility of homeostatic physiological processes requires regulating fluid balance and extracellular pH, intimately connected to acid-base physiology and can be fatal if not maintained ( Hopkins et al., 2022). The pH and HCO3 values show the acid-base balance regulated by the lungs and the kidneys, respectively. Normal bodily processes require harmony between the two. Short- and long-term shifts in the acid-base balance are primarily controlled by the respiratory and renal systems, which work together to achieve this. The body stores both volatile and nonvolatile acids. Carbon dioxide (CO2) from the lungs is an example of a volatile acid, while the kidneys are responsible for excreting metabolic acids (McCance & Huether, 2019). 

2. How do changes in plasma osmolality affect the physiology of erythrocytes? 

The main factor affecting plasma osmolality is the plasma sodium concentration. It is limited to modest ranges under ordinary physiological conditions. Changes in plasma osmolality can cause compensatory reactions like increased water intake or increased water excretion because hypothalamic receptors in the brain are sensitive to these changes. The brain induces thirst and fluid intake when plasma volume or osmolality changes. Additionally, the kidneys are instructed to expel less water to dilute the plasma by the rise in ADH (McCance & Huether, 2019). When red blood cells are placed in plasma with higher osmolarity, fluid moves from the intracellular to the extracellular compartment and shrinks. When the plasma has a lower osmolarity, the red blood cells tend to gain water and may likely burst (McCance & Huether, 2019). 

References 

Hopkins E, Sanvictores T, Sharma S. (2022). Physiology, Acid-Base Balance. 

Stat Pearls Publishing; Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK507807/  

McCance, K. L., & Huether, S. E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed.). Elsevier.