Mary Kramer aged 47, goes to the doctor with complaints of not feeling well. She claims to have a lot of anxiety and is not able to concentrate. Her husband claims that she is no longer keeping up with the house work. She responds that she doesn’t feel ambitious because she just can’t focus anymore and she feels so weak. She also complains of heart palpitations. She said she has also had a lot of sugar cravings and always seems hungry. Last week, after eating dinner, she felt shaky and started to sweat. She then passed out.
Upon examination, Ms. blood pressure is 90/64 mm Hg. Her pulse was a grade of +1 and her heart rate was 70 beats per minute. Her muscle strength was assessed at a grade 3.
Fasting blood tests are ordered with the following results:
Serum glucose- Low
Serum calcium- 9.0 mg/dl
Serum potassium- 3.2 mEq/L
Serum sodium- 153 mEq./L
pH = 7.51
pCO2 = 51 mm Hg
HCO3– = 29 mEq/L
An electrocardiogram was also ordered with the following result:
Slightly prolonged PR interval, ST depression, a flattened T wave and a U wave.
The doctor notes the high insulin and low blood glucose levels and decides to order a CT scan of the pancreas. The scan shows a .75 cm insulinoma. An insulinoma is a tumor that secretes excess insulin.
1. The patient had a pulse that was given a grade of +1. What does this mean? (.5 pt.)
2. The patient muscle strength was a grade 3. What does this mean? (.5 pt.)
a. Based upon what you see in her blood tests, what are two causes for the grade 3 muscle
strength? (1 pt.)
3. Based upon her blood tests, what electrolyte imbalances is she experiencing? (1 pt.)
4. Why is high insulin causing the high or low levels of each of the serum electrolytes you
mentioned in question 3? (2 pts)
5. What is causing the electrocardiogram abnormalities? (1 pt.)
6. Based upon the case study, Ms Marty is experiencing anxiety. Anxiety and low blood
glucose levels can cause the release of epinephrine. Epinephrine and norepinephrine are
often referred to as ________________________________. (.5 pt.)
a. What type of receptor do epinephrine and norepinephrine bind to? (.5 pt.)
b. Explain how activation of more of these receptors causes hypokalemia? (1 pt.)
7. What diagnosis would you make based upon the arterial blood gas values? Make sure to
include if there is compensation and if the compensation is full or partial compensation.
a. What is causing the pH disturbance? (I will not accept hydrogen levels are too low) (1 pt.)