Nurs 3366 - Alteration in Cell Functions

What is Hypoxia?

decrease in O₂ at the cellular level

What are the Sequalae of Hypoxia?

cellular metabolism has to “recycle” through glycolysis rather than continue down the usual aerobic pathway - Anaerobic glycolysis

What are the positives for anaerobic glycolysis?

• it can give 2 molecules of ATP per molecule of glucose to give energy to the cell.

• thus, it is a temporary stop-gap measure

What are the negatives for anaerobic glycolysis?

• 2 molecule of ATP is not enough to keep going for a long time.

• also, every time the metabolic process must “recycle” through
  glycolysis, multiple molecules of pyruvate (pyruvic acid) accumulate,
  resulting in acidosis
  

What is glycogenesis?

process of converting glucose into glycogen for storage in the body

What are the counterregulatory hormones released during hypoglycemia(low blood sugar)?

1. epinephrine from the adrenal medulla

2. cortisol from the adrenal cortex

3. growth hormone (GH) from the pituitary

4. glucagon from the pancreas

(1,2,3 are stress hormones)

What are the roles of the counterregulatory hormones of hypoglycemia?

• “alarms”—sensations of hunger, shakiness, sweating, irritability—these are telling you to “EAT!”

• counterregulatory hormone glucagon stimulates the conversion of glycogen to glucose

What is glycogenolysis?

the process of breaking down glycogen into glucose, which provides energy for the body

What is gluconeogenesis?

the use of any other substance besides carbohydrates for cellular energy; this means breaking down fats and proteins for energy.

What is a product of the breakdown of fats and proteins?

ketones

What are the good characteristics of ketones?

offer the body some energy—usually enough to be a “stop gap” till glucose is available.

What are the bad characteristics of ketones?

• they are acids-- over time there is a danger of acidosis

• they can’t be used by brain cells—brain cells MUST have glucose for energy

What are glycogen storage diseases?

abnormalities in glycogenesis or glycogenolysis

What is an example of a glycogen storage disease?

McArdle’s disease

What is McArdle’s disease?

an autosomal recessive disease in which normal ability to breakdown muscle glycogen (glycogenolysis) is diminished

What are the S&S of McArdle’s disease?

muscle weakness & cramps during exercise because of no energy reserves

What is Type I diabetes?

gluconeogenesis taken to extreme: protein and fats for energy

• people with Type I diabetes mellitus do not make insulin→without insulin, blood glucose levels increase →without insulin, glucose is not able to get into cells and the body turns to sustained gluconeogenesis

resulting in hyperketonemia

What is Hyperketonemia?

high levels of ketones in the blood

How is Hyperketonemia manifested?

• blood test showing high serum ketones.

• blood test showing LOW blood pH—this would be called ketoacidosis

• urine test which shows ketonuria (ketones spill into urine);

• S&S such as acetone breath (excretion via lungs).

What type of patient would be at risk for vitamin deficiencies?

alcoholics

• from poor diets; low in iron and B vitamins such as thiamine

What is a Thiamine(Vit B1) deficiency called?

beriberi & sequelae include neuro-problems

What are examples of neurologic issues associated with thiamine deficiency?

• Wernicke-Korsakoff syndrome

• Paresthesia

What is Wernicke-Korsakoff syndrome?

classically associated with alcoholism and manifested as memory loss and ataxia (staggering, uncoordinated gait)

What is Paresthesia?

numbness & tingling or other unusual sensations, usually in legs

What does cyanide inhibit?

inhibits cytochrome oxidase

What is caused by a Vitamin B12 deficiency?

macrocytic anemia, paresthesia, glossitis. This can be due to alcohol overuse/poor nutrition