Master the CCTC NATCO Exam:
Practice Questions with Answers &
Detailed Rationales
SECTION 1: ORGAN DONATION & DONOR MANAGEMENT (Questions
1–25)
1. What is the primary physiological trigger for the "autonomic storm"
following severe brain injury?
A) Hypoxia
B) Loss of cortical inhibition of the hypothalamus
C) Systemic hypotension
D) Hyperthermia
Answer: B
Rationale: Increased intracranial pressure causes brainstem herniation,
leading to loss of cortical inhibition and a massive sympathetic surge
(autonomic storm), causing hypertension, tachycardia, and vasoconstriction.
,2. Which of the following is an absolute contraindication to the apnea
test?
A) Core temperature < 36°C (96.8°F)
B) Systolic BP < 90 mmHg
C) PaCO2 < 35 mmHg
D) All of the above
Answer: D
Rationale: The apnea test requires core temp ≥ 36°C, SBP ≥ 90 mmHg,
euvolemia, and a baseline PaCO2 of 35-45 mmHg to be valid and safe.
3. A positive apnea test is defined as:
A) PaCO2 ≥ 60 mmHg or a 20 mmHg increase from baseline with no
respiratory effort
B) PaO2 < 60 mmHg
C) SpO2 < 88%
D) Heart rate drop > 20%
Answer: A
Rationale: A positive apnea test confirms brain death by demonstrating
hypercapnia (the primary respiratory drive stimulus) without any respiratory
effort.
4. Which ancillary test is most commonly used when clinical exam or
apnea test cannot be safely completed?
, A) EEG
B) Transcranial Doppler
C) Four-vessel cerebral angiography
D) Nuclear medicine cerebral blood flow scan
Answer: D
Rationale: The radionuclide cerebral blood flow scan (nuclear scan)
showing intracranial absence of blood flow ("hollow skull sign") is the most
widely accepted and utilized ancillary test.
5. Which hormonal replacement is typically initiated to treat diabetes
insipidus in the brain-dead donor?
A) Hydrocortisone
B) Levothyroxine
C) Desmopressin (DDAVP)
D) Insulin
Answer: C
Rationale: Brain death causes posterior pituitary failure, leading to DI.
DDAVP (vasopressin analog) is the treatment of choice to concentrate urine
and prevent severe hypernatremia.
6. The target urine output for a brain-dead organ donor is:
A) 0.5 – 1 mL/kg/hr
B) 1 – 3 mL/kg/hr
, C) 3 – 5 mL/kg/hr
D) > 5 mL/kg/hr
Answer: B
Rationale: Maintaining urine output of 1–3 mL/kg/hr ensures adequate
perfusion and helps preserve organ function for transplantation.
7. A brain-dead donor develops severe hypernatremia (Na > 160
mEq/L). The most likely cause is:
A) SIADH
B) Diabetes insipidus
C) Acute kidney injury
D) Excessive fluid resuscitation
Answer: B
Rationale: Diabetes insipidus from posterior pituitary dysfunction leads to
large volumes of dilute urine, resulting in hypernatremia if free water losses
are not replaced.
8. Which hemodynamic goal is most important in managing a brain-
dead donor?
A) Heart rate < 60 bpm
B) Mean arterial pressure (MAP) ≥ 65 mmHg
C) Central venous pressure (CVP) < 4 mmHg
D) Pulmonary artery wedge pressure > 20 mmHg
Practice Questions with Answers &
Detailed Rationales
SECTION 1: ORGAN DONATION & DONOR MANAGEMENT (Questions
1–25)
1. What is the primary physiological trigger for the "autonomic storm"
following severe brain injury?
A) Hypoxia
B) Loss of cortical inhibition of the hypothalamus
C) Systemic hypotension
D) Hyperthermia
Answer: B
Rationale: Increased intracranial pressure causes brainstem herniation,
leading to loss of cortical inhibition and a massive sympathetic surge
(autonomic storm), causing hypertension, tachycardia, and vasoconstriction.
,2. Which of the following is an absolute contraindication to the apnea
test?
A) Core temperature < 36°C (96.8°F)
B) Systolic BP < 90 mmHg
C) PaCO2 < 35 mmHg
D) All of the above
Answer: D
Rationale: The apnea test requires core temp ≥ 36°C, SBP ≥ 90 mmHg,
euvolemia, and a baseline PaCO2 of 35-45 mmHg to be valid and safe.
3. A positive apnea test is defined as:
A) PaCO2 ≥ 60 mmHg or a 20 mmHg increase from baseline with no
respiratory effort
B) PaO2 < 60 mmHg
C) SpO2 < 88%
D) Heart rate drop > 20%
Answer: A
Rationale: A positive apnea test confirms brain death by demonstrating
hypercapnia (the primary respiratory drive stimulus) without any respiratory
effort.
4. Which ancillary test is most commonly used when clinical exam or
apnea test cannot be safely completed?
, A) EEG
B) Transcranial Doppler
C) Four-vessel cerebral angiography
D) Nuclear medicine cerebral blood flow scan
Answer: D
Rationale: The radionuclide cerebral blood flow scan (nuclear scan)
showing intracranial absence of blood flow ("hollow skull sign") is the most
widely accepted and utilized ancillary test.
5. Which hormonal replacement is typically initiated to treat diabetes
insipidus in the brain-dead donor?
A) Hydrocortisone
B) Levothyroxine
C) Desmopressin (DDAVP)
D) Insulin
Answer: C
Rationale: Brain death causes posterior pituitary failure, leading to DI.
DDAVP (vasopressin analog) is the treatment of choice to concentrate urine
and prevent severe hypernatremia.
6. The target urine output for a brain-dead organ donor is:
A) 0.5 – 1 mL/kg/hr
B) 1 – 3 mL/kg/hr
, C) 3 – 5 mL/kg/hr
D) > 5 mL/kg/hr
Answer: B
Rationale: Maintaining urine output of 1–3 mL/kg/hr ensures adequate
perfusion and helps preserve organ function for transplantation.
7. A brain-dead donor develops severe hypernatremia (Na > 160
mEq/L). The most likely cause is:
A) SIADH
B) Diabetes insipidus
C) Acute kidney injury
D) Excessive fluid resuscitation
Answer: B
Rationale: Diabetes insipidus from posterior pituitary dysfunction leads to
large volumes of dilute urine, resulting in hypernatremia if free water losses
are not replaced.
8. Which hemodynamic goal is most important in managing a brain-
dead donor?
A) Heart rate < 60 bpm
B) Mean arterial pressure (MAP) ≥ 65 mmHg
C) Central venous pressure (CVP) < 4 mmHg
D) Pulmonary artery wedge pressure > 20 mmHg
