D236 PATHO OA EXAM GUIDE
QUESTIONS AND ANSWERS
The body uses the Protein Buffering System, Phosphate Buffering System, and
Carbonic Acid-Bicarbonate System to regulate and maintain homeostatic pH, what is
the consequence of a pH imbalance? - ANSWER -Proteins contain many acidic and
basic group that can be affected by pH changes. Any increase or decrease in blood pH
can alter the structure of the protein (denature), thereby affecting its function as well
Describe the laboratory findings associated with metabolic acidosis, metabolic alkalosis,
respiratory acidosis and respiratory alkalosis. (ie relative pH and CO2 levels). -
ANSWER -Respiratory Acidosis:
Ph <7.35, CO2 >45, HCO3 >26
Respiratory Alkalosis:
Ph >7.35, CO2 <35, HCO3 <22
Metabolic Acidosis:
Ph <7.35, HCO3 <22, CO2 <35
Respiratory Acidosis:
Ph >7.35, HCO3 >26, CO2 >45
Normal ABGs (Arterial Blood Gases) Blood pH: 7.35-7.45 PCO2: 35-45 mm Hg PO2:
90-100 mm Hg HCO3-: 22-26 mEq/L SaO2: 95-100% Respiratory acidosis and
alkalosis are marked by changes in PCO2. Higher = acidosis and lower = alkalosis
Metabolic acidosis and alkalosis are caused by something other than abnormal CO2
levels. This could include toxicity, diabetes, renal failure or excessive GI losses. Here
are the rules to follow to determine if is respiratory or metabolic in nature. -If pH and
PCO2 are moving in opposite directions, then it is the pCO2 levels that are causing the
imbalance and it is respiratory in nature. -If PCO2 is normal or is moving tin the same
direction as the pH, then the imbalance is metabolic in nature.
The anion gap is the difference between measured cations (Na+ and K+) and measured
anions (Cl- and HCO3-), this calculation can be useful in determining the cause of
metabolic acidosis. Why would an increased anion gap be observed in diabetic
ketoacidosis or lactic acidosis? - ANSWER -AG range: 8-16
The anion gap is the calculation of unmeasured anions in the blood. Lactic acid and
ketones both lead to the production of unmeasured anions, which remove HCO3- (a
measured anion) due to buffering of the excess H+ and therefore leads to an increase
in the AG
Why is it important to maintain a homeostatic balance of glucose in the blood (ie
describe the pathogenesis of diabetes)? - ANSWER -Insulin is the hormone responsible
for initiating the uptake of glucose by the cells. Cells use glucose to produce energy
(ATP). In a normal individual, when blood glucose increases, the pancreas is signaled
to produced in insulin, which binds to insulin receptors on a cells surface and initiates
the uptake of glucose. Glucose is a very reactive molecule and if left in the blood, it can
, start to bind to other proteins and lipids, which can lead to loss of function. AGEs are
advanced glycation end products that are a result of glucose reacting with the
endothelial lining, which can lead to damage in the heart and kidneys.
Compare and contrast Type I and Type II Diabetes - ANSWER -Type I diabetes is
caused by lack of insulin. With out insulin signaling, glucose will not be taken into the
cell and leads to high blood glucose (hyperglycemia). Type I is usually treated with
insulin injections. Type II diabetes is caused by a desensitization to insulin signaling.
The insulin receptors are no longer responding to insulin, which also leads to
hyperglycemia. Type II is usually treated with drugs to increase the sensitization to
insulin (metformin), dietary and life-style changes or insulin injections.
Describe some reasons for a patient needing dialysis? - ANSWER -AEIOU-acidosis.
Electrolytes, Intoxication/Ingestion, overload, uremia. Patients with kidney or heart
failure. A build up of phosphates, urea and magnesium are removed from the blood
using a semi-permeable membrane and dialysate. AEIOU: A—acidosis; E—electrolytes
principally hyperkalemia; I—ingestions or overdose of medications/drugs; O—overload
of fluid causing heart failure; U—uremia leading to encephalitis/pericarditis
Compare and contrast hemodialysis and peritoneal dialysis. What are some reasons for
a patient choosing one over the other? - ANSWER -Hemodialysis uses a machine to
pump blood from the body in one tube while dialysate (made of water, electrolytes and
salts) is pumped in the separate tube in the opposite direction. Waste from the blood
diffuses through the semipermeable membrane separating the blood from the dialysate.
Peritoneal Dialysis does not use a machine, but instead injects a solution of water and
glucose into the abdominal cavity. The peritoneum acts as the membrane instead of
dialysis tubing. The waste products diffuse into the abdominal cavity and the waste
solution is then drained from the body. Peritoneal dialysis offers continuous filtration and
is less disruption to the patient's daily routines. However, it does require some training
of the patient and is not recommended for individuals who are overweight or have
severe kidney failure. Hemodialysis provides medical care, but 3 times a week for
several hours sitting at a hospital or clinic. Individuals with acute kidney failure are
recommended to use hemodialysis
How does homeostasis and maintaining optimal physiological health impact your
wellbeing? - ANSWER -Homeostasis acts to create a constant and stable environment
in the body despite internal and external changes. Proteins and other cellular processes
require optimal conditions in order to carry out their functions. Alterations in pH, salt
concentration, temperature, glucose levels, etc. can have negative effects on health, so
it is vital for mechanisms that regulate homeostasis to function properly for maintaining
good health
Differentiate between Innate Immunity and Adaptive Immunity - ANSWER -The innate
immune system encompasses physical barriers and chemical and cellular defenses.
Physical barriers protect the body from invasion. These include things like the skin and
eyelashes. Chemical barriers are defense mechanisms that can destroy harmful agent.
QUESTIONS AND ANSWERS
The body uses the Protein Buffering System, Phosphate Buffering System, and
Carbonic Acid-Bicarbonate System to regulate and maintain homeostatic pH, what is
the consequence of a pH imbalance? - ANSWER -Proteins contain many acidic and
basic group that can be affected by pH changes. Any increase or decrease in blood pH
can alter the structure of the protein (denature), thereby affecting its function as well
Describe the laboratory findings associated with metabolic acidosis, metabolic alkalosis,
respiratory acidosis and respiratory alkalosis. (ie relative pH and CO2 levels). -
ANSWER -Respiratory Acidosis:
Ph <7.35, CO2 >45, HCO3 >26
Respiratory Alkalosis:
Ph >7.35, CO2 <35, HCO3 <22
Metabolic Acidosis:
Ph <7.35, HCO3 <22, CO2 <35
Respiratory Acidosis:
Ph >7.35, HCO3 >26, CO2 >45
Normal ABGs (Arterial Blood Gases) Blood pH: 7.35-7.45 PCO2: 35-45 mm Hg PO2:
90-100 mm Hg HCO3-: 22-26 mEq/L SaO2: 95-100% Respiratory acidosis and
alkalosis are marked by changes in PCO2. Higher = acidosis and lower = alkalosis
Metabolic acidosis and alkalosis are caused by something other than abnormal CO2
levels. This could include toxicity, diabetes, renal failure or excessive GI losses. Here
are the rules to follow to determine if is respiratory or metabolic in nature. -If pH and
PCO2 are moving in opposite directions, then it is the pCO2 levels that are causing the
imbalance and it is respiratory in nature. -If PCO2 is normal or is moving tin the same
direction as the pH, then the imbalance is metabolic in nature.
The anion gap is the difference between measured cations (Na+ and K+) and measured
anions (Cl- and HCO3-), this calculation can be useful in determining the cause of
metabolic acidosis. Why would an increased anion gap be observed in diabetic
ketoacidosis or lactic acidosis? - ANSWER -AG range: 8-16
The anion gap is the calculation of unmeasured anions in the blood. Lactic acid and
ketones both lead to the production of unmeasured anions, which remove HCO3- (a
measured anion) due to buffering of the excess H+ and therefore leads to an increase
in the AG
Why is it important to maintain a homeostatic balance of glucose in the blood (ie
describe the pathogenesis of diabetes)? - ANSWER -Insulin is the hormone responsible
for initiating the uptake of glucose by the cells. Cells use glucose to produce energy
(ATP). In a normal individual, when blood glucose increases, the pancreas is signaled
to produced in insulin, which binds to insulin receptors on a cells surface and initiates
the uptake of glucose. Glucose is a very reactive molecule and if left in the blood, it can
, start to bind to other proteins and lipids, which can lead to loss of function. AGEs are
advanced glycation end products that are a result of glucose reacting with the
endothelial lining, which can lead to damage in the heart and kidneys.
Compare and contrast Type I and Type II Diabetes - ANSWER -Type I diabetes is
caused by lack of insulin. With out insulin signaling, glucose will not be taken into the
cell and leads to high blood glucose (hyperglycemia). Type I is usually treated with
insulin injections. Type II diabetes is caused by a desensitization to insulin signaling.
The insulin receptors are no longer responding to insulin, which also leads to
hyperglycemia. Type II is usually treated with drugs to increase the sensitization to
insulin (metformin), dietary and life-style changes or insulin injections.
Describe some reasons for a patient needing dialysis? - ANSWER -AEIOU-acidosis.
Electrolytes, Intoxication/Ingestion, overload, uremia. Patients with kidney or heart
failure. A build up of phosphates, urea and magnesium are removed from the blood
using a semi-permeable membrane and dialysate. AEIOU: A—acidosis; E—electrolytes
principally hyperkalemia; I—ingestions or overdose of medications/drugs; O—overload
of fluid causing heart failure; U—uremia leading to encephalitis/pericarditis
Compare and contrast hemodialysis and peritoneal dialysis. What are some reasons for
a patient choosing one over the other? - ANSWER -Hemodialysis uses a machine to
pump blood from the body in one tube while dialysate (made of water, electrolytes and
salts) is pumped in the separate tube in the opposite direction. Waste from the blood
diffuses through the semipermeable membrane separating the blood from the dialysate.
Peritoneal Dialysis does not use a machine, but instead injects a solution of water and
glucose into the abdominal cavity. The peritoneum acts as the membrane instead of
dialysis tubing. The waste products diffuse into the abdominal cavity and the waste
solution is then drained from the body. Peritoneal dialysis offers continuous filtration and
is less disruption to the patient's daily routines. However, it does require some training
of the patient and is not recommended for individuals who are overweight or have
severe kidney failure. Hemodialysis provides medical care, but 3 times a week for
several hours sitting at a hospital or clinic. Individuals with acute kidney failure are
recommended to use hemodialysis
How does homeostasis and maintaining optimal physiological health impact your
wellbeing? - ANSWER -Homeostasis acts to create a constant and stable environment
in the body despite internal and external changes. Proteins and other cellular processes
require optimal conditions in order to carry out their functions. Alterations in pH, salt
concentration, temperature, glucose levels, etc. can have negative effects on health, so
it is vital for mechanisms that regulate homeostasis to function properly for maintaining
good health
Differentiate between Innate Immunity and Adaptive Immunity - ANSWER -The innate
immune system encompasses physical barriers and chemical and cellular defenses.
Physical barriers protect the body from invasion. These include things like the skin and
eyelashes. Chemical barriers are defense mechanisms that can destroy harmful agent.
