Navigation » List of Schools, Subjects, and Courses » Physiology 001 – Introduction to Human Physiology » Discussions » Discussion Topic #4: Respiratory & Renal » Discussion Topic #4: Respiratory & Renal Sample Answers
Discussion Topic #4: Respiratory & Renal
Acid-Base Homeostasis: Type 1 Diabetes Patient Case Study
Part 1: Oregon State University Anatomy & Physiology Course – 26.4: Acid-Base Balance (Links to an external site.)
The link above is required reading using Oregon State University’s open source textbook for their Anatomy & Physiology course. This is a supplement to the acid-base regulation lecture discussions in Chapters 13 & 14 of our course.
The key here is that you have two systems, respiratory and renal, working together to address situations where acid/base homeostasis is disturbed.
Part 2: Clinical Case Study – Diabetic ketoacidosis
Read the case summary below and then answer the questions that follow.
Case: During your shift in the ER, a 21-year old noncompliant male with a history of type I (insulin-dependent) diabetes mellitus was found in a coma. Your triage assessment and the lab testing revealed the following:
- Hyperglycemia: High blood glucose.
- High urine glucose.
- High urine ketones and serum ketones.
- Low serum bicarbonate <12 mEq/L.
- Exaggerated respiration.
- Breath has acetone odor.
- Hypotensive: blood pressure was 90/60 mm Hg.
- Tachycardia: Pulse weak and rapid (120 bpm).
Based on your understanding of both the respiratory and renal regulation of blood pH, answer the following:
- Is this patient experiencing respiratory or metabolic acidosis? Why?
- How does the following formula represent the respiratory & renal systems’ regulation of acid-base balance (remember that the enzyme carbonic anhydrase catalyzes the forward reaction between carbon dioxide and water):
CO2 + H2O ↔ H2CO3 ↔ H+ + HCO3–
Discussion Topic #4: Respiratory & Renal Answer
- Metabolic acidosis. Because he is suffering from diabetes type 1 and has severe hyperglycemia that is associated with metabolic acidosis. He also has developed ketone bodies that are acidic in nature and that consequently depleted the bicarbonate level in the body. Ketone bodies are formed when the body burns fat for fuel instead of glucose or sugar.