Endocrine Flashcards
The endocrine section makes up roughly five questions on your CCRN exam, so about 4% of the exam is devoted to this topic. Endocrine is a relatively small area on the CCRN exam, but there are a few key points to learn and master. (21 cards)
A patient diagnosed with a brain tumor was recently admitted to the ICU
due to suspected diabetes insipidus. The previous hour urine output totaled
500 mL. The physician has ordered lactated Ringer’s fluid replacement and
desmopressin. Which of the following lab values would indicate improvement
of the condition?
A. Serum sodium 151 mEq/L
B. Serum osmolality 270 mOsm/kg
C. Serum potassium 4.0 mEq/L
D. Serum osmolality 290 mOsm/kg
Answer: D
Rationale: The normal range for serum osmolality is 275–295 mOsm/kg.
Patients experiencing diabetes insipidus have a hyperosmolar state >295 mOsm/
kg. If the treatment is working, a corrected osmolality is expected on the higher
end of normal. A normal sodium between 135 and 145 mEq/L would indicate
improvement of DI. The potassium of 4.0 mEq/L is a normal number, but this is
not the main concern for DI
Aside from polyuria for the patient in question 1, what other findings would
the nurse recognize as likely diabetes insipidus?
A. Urine specific gravity 1.002
B. Serum osmolality 265 mOsm/kg
C. Serum sodium 121 mEq/L
D. BP 135/70, HR 90
Answer: A
Rationale: Questions like this that ask you to list signs and symptoms of diseases
are relatively common on the CCRN exam. For diabetes insipidus, a diluted
urine is expected; this is shown in a specific gravity of 1.002. Nocturia along with
polyuria and polydipsia are also expected in DI. Serum osmolality and sodium
would be elevated in DI, not reduced. With a patient voiding excessive amounts of
fluid, it can be expected the patient may be hypovolemic with a low blood pressure
and reflex tachycardia
A patient with a history of small cell lung cancer was recently brought to the
ED due to excessive vomiting. Current labs include Na+ 115 mEq/L, urine
output 20 mL/hr, and a serum osmolality of 255 mOsm/kg. Which of the
following would be the most important for the nurse to do first?
A. Administer hypertonic saline 100 mL/hr IV
B. Assess for tremors, seizure activity
C. Administer furosemide 40 mg IV
D. Assess deep tendon reflexes
Answer: B
Rationale: The patient is showing signs and symptoms of SIADH. The excessive
vomiting is especially worrisome, as it is an indication of dilutional hyponatremia.
The biggest risk at this moment is seizure activity that may lead to death if
left unmanaged. The nurse should assess seizure activity first, then move on
to treatments. A hypertonic solution may be used, but 100 mL/hr is excessive.
Remember that the goal of sodium movement is incremental improvements.
Changes that are too quick are dangerous. A diuretic is used at times in SIADH,
but it is not the immediate priority. Deep tendon reflex changes are often seen with
changes in serum magnesium, not sodium levels.
A 78-year-old female with Type 2 diabetes was admitted from a nursing home
due to continued high fingerstick glucose checks with worsening confusion.
The most recent glucose taken was 650 mg/dL. Which of the following would
indicate a diagnosis of HHS instead of DKA?
A. Osmolality 330 mOsm/kg, glucose 650 mg/dL
B. Osmolality 260 mOsm/kg, polyuria
C. Osmolality 275 mOsm/kg, serum pH 7.20
D. Osmolality 330 mOsm/kg, tachypnea
Answer: A
Rationale: A diagnosis of HHS over DKA can be seen first by serum osmolality.
HHS is a hyperosmolar disorder; DKA is not. The elevated osmolality above 320
mOsm/kg displays HHS. Glucose is typically much higher in HHS than DKA as
well, typically above 600 mg/dL. Polyuria can be a symptom of both HHS and
DKA. HHS is not an acidic state like DKA. Deep tachypneic breathing (Kussmaul)
is seen in DKA, not HHS.
The patient in question 4 was started on normal saline and an insulin drip
in the ICU. Current labs show glucose 290 mg/dL, serum osmolality 300
mOsm/kg, BP 110/80 mmHg, HR 95. Which of the following interventions is
appropriate at this time?
A. Assess for glucosuria
B. Stop the insulin drip
C. Decrease normal saline infusion to 25 mL/hr
D. Dextrose IV continuous
Answer: D
Rationale: The treatment for this patient has been working. There has been
improvement in both glucose and serum osmolality. At this time, it is appropriate
to add dextrose to the crystalloid treatment. When the glucose falls below 300 mg/
dL, it is time to add dextrose. The insulin drip will be decreased by protocol but is
not discontinued until the osmolality issues have been resolved and mental status
has improved. The hydration via normal saline will also continue until osmolality
has resolved. Assessing glycosuria is not needed, the diagnosis of HHS already
exists.
A hospitalized patient with diabetes and hypertension has been prescribed
metoprolol by the physician. What would the nurse emphasize in the teaching
to this patient at discharge?
A. Call the physician if bradycardic
B. Understand signs and symptoms of hypoglycemia
C. Increase glycemic food intake
D. Hold metoprolol if hypoglycemic
Answer: B
Rationale: Extra care must be given to diabetic patients prescribed beta blockers
like metoprolol. Tachycardia is an early sign of hypoglycemia; with a beta blocker,
the medication will mask this symptom and the patient may not be aware they
are hypoglycemic. It is important for the patient to understand the full picture
of what hypoglycemia may look like for them. Unless the patient is experiencing
other problems, bradycardia does not warrant calling the physician for this patient.
Increasing foods high in sugar is not a good idea for any diabetic patient. It may
assist this patient from avoiding hypoglycemia, but they will likely experience
hyperglycemia and unregulated diabetes due to the drastic dietary change. Patients
do not choose to hold meds on their own accord; changes to scheduled medications
require a higher scope of practice.
Which of the following symptoms may the patient in question 6 expect if
hypoglycemic?
A. Changes in vision
B. Tachycardia
C. Fever and diaphoresis
D. Oliguria
Answer: A
Rationale: Diabetic patients who take metoprolol should be taught the signs
and symptoms of hypoglycemia they may expect. Later signs of hypoglycemia
are often the first signs these patients experience. Vision changes and other CNS
issues (slurred speech, confusion) may be seen. While diaphoresis is considered an
early sign of hypoglycemia, something this patient may not experience due to the
beta blocker, a fever with diaphoresis is more aligned with HHS. Oliguria is not a
symptom of hypoglycemia.
A patient remains intubated in the ICU post-op day 2 from a complicated
thoracotomy. The patient is currently sedated with tube feedings at 50 mL/hr.
Morning labs showed abnormal sodium at 150 mg/dL. The physician decides to
add-on a serum osmolality to lab work; the result is 320 mOsm/kg. Which of
the following interventions is indicated at this time?
A. Decrease rate on tube feedings
B. Decrease rate on normal saline drip
C. Add free water flushes to tube feedings
D. Begin hypotonic infusion
Answer: C
Rationale: This patient is showing possible signs of dehydration or at the least
hypernatremia with hyperosmolality. Sodium changes should be done slowly. By
adding free water flushes to the tube feeding, the patient will receive more fluid
enterally. This is also considered a less invasive measure than other options like
a hypotonic infusion. Decreasing the tube feeding or a current isotonic infusion
would make the problem worse. This patient needs more fluid, not less.
Serum osmolality is affected by a multitude of factors. In which of the
following would the nurse expect to see increases in the serum osmolality?
A. SIADH
B. Alzheimer’s patient with excessive water intake
C. Decreased BUN (urea)
D. Dehydration in an elderly diabetic patient
Answer: D
Rationale: Dehydration may come about for many reasons: vomiting, diarrhea,
sweating, burns. A decrease in overall body fluid causes an increase in the
concentration of fluids (osmolality). It is especially important for the elderly to
receive enough fluid intake. A dehydrated elderly diabetic patient has an increased risk
of developing HHS if not corrected early enough. SIADH, excessive fluid intake,
and a decreased BUN would cause a decrease in serum osmolality, not an increase.
Remember that the main particles of osmolality include sodium, BUN, and
glucose.
An 18-year-old patient was recently admitted after being witnessed collapsing
outdoors on a hot day. Upon admission, their skin is cold and clammy to
the touch. The patient remains obtunded and unable to answer questions. A
classmate is at the bedside and states she believes the patient to be diabetic. Which of
the following findings would the nurse expect?
A. Glucose 45, HR 50, urine specific gravity 1.010
B. Glucose 600, HR 140, acetone breath
C. Glucose 60, BP 160/80, polyuria
D. Glucose 45, HR 130, BP 90/60
Answer: D
Rationale: The story and symptoms most closely match hypoglycemia with likely
dehydration given the hot day. Hot weather may also precipitate hypoglycemia
due to increased body metabolism. The heart rate will be increased with other
symptoms of dehydration (increased urine specific gravity, increased serum
osmolality, decreased blood pressure). Acetone breath is seen in DKA. Polyuria is
seen in hyperglycemia.
Which of the following interventions is considered to be the fi rst-line treatment in a
patient with a hyperglycemic emergency?
A. Insulin replacement
B. Fluid administration
C. Administer sodium bicarbonate
D. Replace magnesium losses
B
Fluid administration is considered to be the fi rst-line treatment in managing hyperglycemic
emergencies (DKA, HHNS). Fluid is used to correct the signifi cant water depletion
that occurs with severe hyperglycemia and establishes reperfusion of the kidneys.
The administration of fl uid begins to correct the hyperglycemia and can decrease
serum glucose concentrations by up to 50 mg/dL. Insulin replacement should be initiated
after initial fl uid resuscitation is given. Sodium bicarbonate is not usually recommended
in the management of DKA/HHNS. Electrolyte replacement is a component
of treatment but fl uids are still initiated before Mg+ replacement.
A patient presents with an altered LOC and blood glucose level of 650 mg/dL. The following
lab values were obtained on admission:
K+ 3.1
Na+ 126
Mg+ 3.0
PO4
+ 4.0
D
Initiation of insulin should be delayed until potassium is administered, if potassium
levels are less than 3.5 mEq/L initially. Once potassium is above 3.5 mEq/L, IV fl uids
and insulin infusions may be initiated. Administration of insulin, either bolus or continuous
infusion, will drive the potassium back into the cells causing an even greater
decrease of potassium and an increase in arrhythmias.
Based on the above fi ndings, which of the following interventions should be the initial
treatment?
A. Administer bolus dose of insulin
B. Initiate continuous low-dose infusion of insulin
C. Bolus 1/L IV fl uids over 30 minutes
D. Administer potassium IV
A
DI is a neuroendocrine disorder that presents with large amounts of diuresis. It is caused
by a lack of ADH either being produced from the hypothalamus or released from the
pituitary. The diuresis results in hemoconcentration and hypernatremia. SIADH and
CSWS both cause hyponatremia. DM does not necessarily affect sodium levels.
Which of the following disorders can cause hypernatremia?
A. DI
B. SIADH
C. CSWS
D. Diabetes mellitus (DM)
During treatment of stress-induced hyperglycemia, what is the most signifi cant complication
of strict glycemic control of 80 to 110 mg/dL?
A. Cerebral edema
B. Hypoglycemia
C. Hyponatremia
D. Hyperkalemia
What is the clinical fi nding most commonly associated with hypoglycemia in critically
ill patients?
A. Paroxysmal supraventricular tachycardia (SVT)
B. Muscle twitching
C. Fatigue
D. Cognitive impairment
Which of the following statements best explains the lack of ketoacidosis in HHNS?
A. Become sicker faster than DKA patients and will seek medical assistance before
ketones are produced
B. Higher osmolality of HHNS blocks fatty acid oxidation preventing ketone production
C. HHNS patients have the presence of small amounts of insulin, which prevents
ketone production
D. The kidneys retain a greater amount of bicarbonate in HHNS patients to correct the
metabolic acidosis
A 46-year-old male is admitted for a subarachnoid hemorrhage and aneurysm clipping.
Three days after admission, the following labs and vital signs are obtained:
Blood pressure (BP) 124/64
Heart rate (HR) 72
Respiratory rate (RR) 16
Urine output (UO) 75 to 100 cc/hr
Na+ 124 mEq/L
K+ 3.6
Glucose 145 mg/dL
Serum osmolality 280 mEq/L
Urine Na+ 35 mmol/L
Which of the following is the most likely cause for the hyponatremia?
A. DI
B. SIADH
C. CSWS
D. DM
A patient is diagnosed with CSWS following a traumatic brain injury. His current
sodium level is 120 mEq/L. The physician has ordered 3% NaCl to be administered at
a rate of 30 mL/hr and sodium levels checked every 4 hours. Which of the following is
a complication of administering hypertonic normal saline?
A. Cerebral edema
B. Central pontine myelinolysis (CPM)
C. Abdominal compartment syndrome (ACS)
D. Acute respiratory distress syndrome (ARDS)
A patient with traumatic brain injury voided 350 mL/hr in the previous hour. Which of
the following would be the most likely result of the sudden diuresis?
A. Over-use of Lasix
B. Volume overload
C. DM
D. DI
Which of the following laboratory fi ndings would indicate a diuresis following a brain
tumor resection as a result of DI?
A. Low serum osmolality
B. Low urine osmolality
C. Hyponatremia
D. High urine specifi c gravity
