NR 283 Pathophysiology Exam 2 | Questions and
Answers + Expert Rationales | 2026 Updated |
100% correct | Chamberlain
1. A patient with severe right-sided heart failure presents with significant dependent edema
in the lower extremities. Which hydrostatic or oncotic pressure change is causing this fluid
shift?
A) Decreased capillary hydrostatic pressure
B) Increased capillary hydrostatic pressure
C) Increased capillary oncotic pressure
D) Increased interstitial hydrostatic pressure
Correct Answer: B. Increased capillary hydrostatic pressure
Expert Rationale: Heart failure causes venous congestion and a backup of blood, which raises
the hydrostatic pressure within the capillaries. This increased pressure forces fluid out into the
interstitial space, leading to dependent edema. The fluid shift is due to the "push" of hydrostatic
pressure exceeding the "pull" of osmotic pressure at the venous end of the capillary. This is a
classic example of how hemodynamic alterations lead to edema formation.
2. A patient with severe malnutrition and liver failure has a dangerously low serum albumin
level. The nurse notes generalized edema. Which mechanism explains this fluid shift?
A) Increased capillary hydrostatic pressure
B) Decreased capillary oncotic pressure
C) Decreased interstitial fluid osmotic pressure
D) Decreased capillary permeability
Correct Answer: B. Decreased capillary oncotic pressure
Expert Rationale: Albumin provides the primary pulling force (oncotic pressure or colloid
osmotic pressure) that keeps fluid inside blood vessels. Low albumin, as seen in malnutrition
and liver failure, decreases capillary oncotic pressure, allowing fluid to leak into tissues and
causing generalized edema. This is the "pull" mechanism failing at the venous level, where
waste is normally eliminated. This is a classic example of how plasma protein deficits cause fluid
shifts .
,3. An arterial blood gas (ABG) analysis shows: pH 7.25, PaCO2 52 mmHg, and HCO3 24 mEq/L.
How should the nurse interpret these findings?
A) Uncompensated metabolic acidosis
B) Uncompensated respiratory acidosis
C) Compensated metabolic acidosis
D) Uncompensated respiratory alkalosis
Correct Answer: B. Uncompensated respiratory acidosis
Expert Rationale: The pH is below 7.35, indicating acidosis. The PaCO2 is elevated above 45
mmHg, indicating a respiratory cause (hypoventilation). The HCO3 is within normal range (22-26
mEq/L), meaning no metabolic compensation has occurred yet. This is uncompensated
respiratory acidosis. Renal compensation (bicarbonate retention) takes hours to days to
develop, so this is an acute respiratory acidosis pattern .
4. A patient with an intestinal obstruction has been undergoing continuous, high-output
gastric suctioning for 48 hours. Which acid-base imbalance is this patient at highest risk for
developing?
A) Respiratory acidosis
B) Respiratory alkalosis
C) Metabolic acidosis
D) Metabolic alkalosis
Correct Answer: D. Metabolic alkalosis
Expert Rationale: Gastric secretions contain high amounts of hydrochloric acid (HCl). Losing
massive amounts of stomach acid via suctioning results in an excess of base in the body, causing
metabolic alkalosis. This is one of the classic causes of metabolic alkalosis, along with prolonged
emesis and antacid overdose. The bicarbonate level rises above 26 mEq/L as the body retains
base to compensate for acid loss .
5. A patient presents with deep, rapid, sighing respirations known as Kussmaul breathing.
Laboratory results reveal severe metabolic acidosis. What is the physiological purpose of this
respiratory pattern?
A) To retain carbon dioxide to lower the pH
B) To blow off carbon dioxide and raise the pH
,C) To increase oxygen delivery to tissues
D) To decrease respiratory rate
Correct Answer: B. To blow off carbon dioxide and raise the pH
Expert Rationale: Kussmaul respirations are deep, rapid, sighing breaths that represent the
body's respiratory compensation for metabolic acidosis. By hyperventilating, the patient blows
off carbon dioxide (CO2), which decreases the acid load and raises the pH toward normal. This is
the body's attempt to compensate for the metabolic acidosis by altering the respiratory
component. Kussmaul breathing is classic in diabetic ketoacidosis (DKA). The respiratory system
acts rapidly (minutes to hours) to compensate for metabolic disturbances.
6. What is the primary clinical manifestation of a stress ulcer?
A) Bowel obstruction
B) Bleeding
C) Pulmonary embolism
D) Hepatomegaly
Correct Answer: B. Bleeding
Expert Rationale: The primary clinical manifestation of stress-related mucosal disease (stress
ulcer) is bleeding, which is uncommon but occurs more readily with the presence of
coagulopathy and more than 48 hours of mechanical ventilation. Stress ulcers are associated
with severe physiological stress, such as burns (Curling ulcers), head trauma (Cushing ulcers), or
critical illness. The bleeding results from mucosal ischemia and acid injury. Bleeding can be life-
threatening and is the primary concern.
7. A 20-year-old recently diagnosed with lactose intolerance eats an ice cream cone and
develops diarrhea. This diarrhea can be classified as which type?
A) Osmotic diarrhea
B) Secretory diarrhea
C) Hypotonic diarrhea
D) Motility diarrhea
Correct Answer: A. Osmotic diarrhea
Expert Rationale: A nonabsorbable substance in the intestine leads to osmotic diarrhea. In
lactose intolerance, the undigested lactose remains in the intestinal lumen, drawing water into
, the bowel by osmosis and causing watery diarrhea. Secretory diarrhea (B) is caused by bacterial
infections that stimulate fluid secretion. Hypotonic diarrhea is not a recognized classification.
Motility diarrhea occurs when food is not mixed properly or motility is increased. The document
notes this distinction clearly .
8. Which type of diarrhea would most likely occur with a bacterial GI infection?
A) Osmotic diarrhea
B) Secretory diarrhea
C) Hypotonic diarrhea
D) Motility diarrhea
Correct Answer: B. Secretory diarrhea
Expert Rationale: Bacterial infections lead to secretory diarrhea, where enterotoxins stimulate
the intestinal epithelial cells to actively secrete fluid and electrolytes into the intestinal lumen.
This is different from osmotic diarrhea (A), where a nonabsorbable substance draws water into
the intestine. Secretory diarrhea continues even when the patient is fasting. Common causes
include Vibrio cholerae, E. coli, and Salmonella infections .
9. A 45-year-old male complains of heartburn after eating and difficulty swallowing. These
symptoms support which diagnosis?
A) Pyloric stenosis
B) Gastric cancer
C) Achalasia
D) Hiatal hernia
Correct Answer: D. Hiatal hernia
Expert Rationale: Regurgitation, dysphagia (difficulty swallowing), and epigastric discomfort
after eating are common in individuals with hiatal hernia. Pyloric stenosis is manifested by
projectile vomiting. Gastric cancer is not typically manifested by heartburn alone. Achalasia is a
form of functional dysphagia caused by loss of esophageal innervation. Hiatal hernia is a
protrusion of the stomach through the diaphragm, and symptoms are related to GERD
secondary to the hernia .
10. Which serious complication can occur with paraesophageal hiatal hernia?
Answers + Expert Rationales | 2026 Updated |
100% correct | Chamberlain
1. A patient with severe right-sided heart failure presents with significant dependent edema
in the lower extremities. Which hydrostatic or oncotic pressure change is causing this fluid
shift?
A) Decreased capillary hydrostatic pressure
B) Increased capillary hydrostatic pressure
C) Increased capillary oncotic pressure
D) Increased interstitial hydrostatic pressure
Correct Answer: B. Increased capillary hydrostatic pressure
Expert Rationale: Heart failure causes venous congestion and a backup of blood, which raises
the hydrostatic pressure within the capillaries. This increased pressure forces fluid out into the
interstitial space, leading to dependent edema. The fluid shift is due to the "push" of hydrostatic
pressure exceeding the "pull" of osmotic pressure at the venous end of the capillary. This is a
classic example of how hemodynamic alterations lead to edema formation.
2. A patient with severe malnutrition and liver failure has a dangerously low serum albumin
level. The nurse notes generalized edema. Which mechanism explains this fluid shift?
A) Increased capillary hydrostatic pressure
B) Decreased capillary oncotic pressure
C) Decreased interstitial fluid osmotic pressure
D) Decreased capillary permeability
Correct Answer: B. Decreased capillary oncotic pressure
Expert Rationale: Albumin provides the primary pulling force (oncotic pressure or colloid
osmotic pressure) that keeps fluid inside blood vessels. Low albumin, as seen in malnutrition
and liver failure, decreases capillary oncotic pressure, allowing fluid to leak into tissues and
causing generalized edema. This is the "pull" mechanism failing at the venous level, where
waste is normally eliminated. This is a classic example of how plasma protein deficits cause fluid
shifts .
,3. An arterial blood gas (ABG) analysis shows: pH 7.25, PaCO2 52 mmHg, and HCO3 24 mEq/L.
How should the nurse interpret these findings?
A) Uncompensated metabolic acidosis
B) Uncompensated respiratory acidosis
C) Compensated metabolic acidosis
D) Uncompensated respiratory alkalosis
Correct Answer: B. Uncompensated respiratory acidosis
Expert Rationale: The pH is below 7.35, indicating acidosis. The PaCO2 is elevated above 45
mmHg, indicating a respiratory cause (hypoventilation). The HCO3 is within normal range (22-26
mEq/L), meaning no metabolic compensation has occurred yet. This is uncompensated
respiratory acidosis. Renal compensation (bicarbonate retention) takes hours to days to
develop, so this is an acute respiratory acidosis pattern .
4. A patient with an intestinal obstruction has been undergoing continuous, high-output
gastric suctioning for 48 hours. Which acid-base imbalance is this patient at highest risk for
developing?
A) Respiratory acidosis
B) Respiratory alkalosis
C) Metabolic acidosis
D) Metabolic alkalosis
Correct Answer: D. Metabolic alkalosis
Expert Rationale: Gastric secretions contain high amounts of hydrochloric acid (HCl). Losing
massive amounts of stomach acid via suctioning results in an excess of base in the body, causing
metabolic alkalosis. This is one of the classic causes of metabolic alkalosis, along with prolonged
emesis and antacid overdose. The bicarbonate level rises above 26 mEq/L as the body retains
base to compensate for acid loss .
5. A patient presents with deep, rapid, sighing respirations known as Kussmaul breathing.
Laboratory results reveal severe metabolic acidosis. What is the physiological purpose of this
respiratory pattern?
A) To retain carbon dioxide to lower the pH
B) To blow off carbon dioxide and raise the pH
,C) To increase oxygen delivery to tissues
D) To decrease respiratory rate
Correct Answer: B. To blow off carbon dioxide and raise the pH
Expert Rationale: Kussmaul respirations are deep, rapid, sighing breaths that represent the
body's respiratory compensation for metabolic acidosis. By hyperventilating, the patient blows
off carbon dioxide (CO2), which decreases the acid load and raises the pH toward normal. This is
the body's attempt to compensate for the metabolic acidosis by altering the respiratory
component. Kussmaul breathing is classic in diabetic ketoacidosis (DKA). The respiratory system
acts rapidly (minutes to hours) to compensate for metabolic disturbances.
6. What is the primary clinical manifestation of a stress ulcer?
A) Bowel obstruction
B) Bleeding
C) Pulmonary embolism
D) Hepatomegaly
Correct Answer: B. Bleeding
Expert Rationale: The primary clinical manifestation of stress-related mucosal disease (stress
ulcer) is bleeding, which is uncommon but occurs more readily with the presence of
coagulopathy and more than 48 hours of mechanical ventilation. Stress ulcers are associated
with severe physiological stress, such as burns (Curling ulcers), head trauma (Cushing ulcers), or
critical illness. The bleeding results from mucosal ischemia and acid injury. Bleeding can be life-
threatening and is the primary concern.
7. A 20-year-old recently diagnosed with lactose intolerance eats an ice cream cone and
develops diarrhea. This diarrhea can be classified as which type?
A) Osmotic diarrhea
B) Secretory diarrhea
C) Hypotonic diarrhea
D) Motility diarrhea
Correct Answer: A. Osmotic diarrhea
Expert Rationale: A nonabsorbable substance in the intestine leads to osmotic diarrhea. In
lactose intolerance, the undigested lactose remains in the intestinal lumen, drawing water into
, the bowel by osmosis and causing watery diarrhea. Secretory diarrhea (B) is caused by bacterial
infections that stimulate fluid secretion. Hypotonic diarrhea is not a recognized classification.
Motility diarrhea occurs when food is not mixed properly or motility is increased. The document
notes this distinction clearly .
8. Which type of diarrhea would most likely occur with a bacterial GI infection?
A) Osmotic diarrhea
B) Secretory diarrhea
C) Hypotonic diarrhea
D) Motility diarrhea
Correct Answer: B. Secretory diarrhea
Expert Rationale: Bacterial infections lead to secretory diarrhea, where enterotoxins stimulate
the intestinal epithelial cells to actively secrete fluid and electrolytes into the intestinal lumen.
This is different from osmotic diarrhea (A), where a nonabsorbable substance draws water into
the intestine. Secretory diarrhea continues even when the patient is fasting. Common causes
include Vibrio cholerae, E. coli, and Salmonella infections .
9. A 45-year-old male complains of heartburn after eating and difficulty swallowing. These
symptoms support which diagnosis?
A) Pyloric stenosis
B) Gastric cancer
C) Achalasia
D) Hiatal hernia
Correct Answer: D. Hiatal hernia
Expert Rationale: Regurgitation, dysphagia (difficulty swallowing), and epigastric discomfort
after eating are common in individuals with hiatal hernia. Pyloric stenosis is manifested by
projectile vomiting. Gastric cancer is not typically manifested by heartburn alone. Achalasia is a
form of functional dysphagia caused by loss of esophageal innervation. Hiatal hernia is a
protrusion of the stomach through the diaphragm, and symptoms are related to GERD
secondary to the hernia .
10. Which serious complication can occur with paraesophageal hiatal hernia?
