Certified Emergency Nurse (CEN) Exam | Expert
Verified Questions and Answers | Most Recent
2026 Update
• hypovolemic shock . CORRECT ANSWER: decreased cellular perfusion due to lack
of circulating volume
• cardiogenic shock . CORRECT ANSWER: decreased cellular perfusion secondary to
failure of the central pump
• distributive shock . CORRECT ANSWER: decreased cellular perfusion secondary to
maldistribution of the oxygen to the periphery
• obstructive shock . CORRECT ANSWER: decreased cellular perfusion secondary to
obstruction of blood into or out of the ventricles (pulmonary embolism, pericardial
tamponade, tension pneumothorax)
• sympathetic nervous system . CORRECT ANSWER: fight or flight
adrenergic system
s/s: vasoconstriction, glycogenolysis, diaphoresis, increased HR, increased RR,
increased water and sodium reabsorption, bronchodilation
• parasympathetic nervous system . CORRECT ANSWER: rest and digest
cholinergic system
s/s: vasodilation, glucogenesis, dry skin, decreased HR, decreased respiratory rate,
bronchoconstriction
• beta one receptors . CORRECT ANSWER: -one heart, beta one affects the heart
(contractility, automaticity, heart rate)
• beta two receptors . CORRECT ANSWER: -two lungs, beta two mainly affects the
lungs (bronchodilation, respiratory rate)
• agonist . CORRECT ANSWER: stimulates a system
• antagonist . CORRECT ANSWER: diminishes system response
• hyponatremia . CORRECT ANSWER: (over hydration)
-s/s: symptoms of water retention, swelling, confusion, apathy, sense of impending
doom, muscle cramps
,-treatment: water restriction, oral sodium replacement, slow replacement with hypertonic
saline (3-5% saline solution)
-correcting too rapidly can cause central pontine myelinolysis (flaccid paralysis,
dysarthria, dysphagia, hypotension)
• hypernatremia . CORRECT ANSWER: (dehydration)
-s/s: altered mental status, fatigue, lethargy, confusion, coma, weakness, diarrhea
-treatment: correct hypovolemia, treat underlying cause (fever, vomiting, diabetes
insipidus, lower serum sodium levels (slowly replace total body water deficit)
-sodium and chloride tend to elevate and decrease together
• hyperkalemia . CORRECT ANSWER: -s/s:
early: muscular excitability, irritability, nausea, vomiting, diarrhea
late: muscular weakness, fatigue, generalized weakness, distal limb paresthesia, tetany,
respiratory depression, ascending paralysis
cardiovascular: peaked t wave, elongated PR interval, absent p wave, enlarging QRS
complex
treatment:
-stabilize cardiac membrane: calcium chloride or calcium gluconate
-shift potassium into the cells: albuterol, insulin, dextrose
-remove potassium from the cells: hemodialysis, NS and furosemide, ion exchange
resin (kayexalate)
-common causes: rental failure, cellular death (rhabdomyelosis, tumor lysis syndrome,
crush injury, burns), acidosis
• hypokalemia . CORRECT ANSWER: s/s: frequently asymptomatic, weakness,
hyporeflexia, tetany, paralysis to lower extremities, respiratory failure, prominent U wave
on EKG causing a camel hump appearance to the t wave, st depression
treatment: oral or IV potassium
-hypokalemia and hypomagnesemia often co-exist so correct magnesium with
potassium
, • hypermagnesemia . CORRECT ANSWER: s/s: neuromuscular depression, decreased
deep tendon reflex, constipation, anorexia, nausea, vomiting, fatigue, diffuse body
aches, bradycardia, hypotension, tall t waves, depressed ST segments
-treatment: reduce serum magnesium (fluids, loop diuretics) reduce ingestion of
magnesium, dialysis
• what foods contain magnesium . CORRECT ANSWER: dark leafy greens, nuts,
seeds, fish, beans, whole grains, avocados, yogurt, bananas, dried fruit, dark chocolate
• hypomagnesemia . CORRECT ANSWER: s/s: mild to moderate elevations
(asymptomatic)
-severe elevations cause neuromuscular excitability (muscular cramping, tetanic
contractions, hyperreflexia, perioral or finger paresthesia, positive chovsteks sign,
positive trousseau's sign, seizures, prolonged PR interval, widened QRS complex
-treatment: mild: oral magnesium supplements
severe: IV magnesium
• chvosteks sign . CORRECT ANSWER: twitch in the facial muscles that occurs when
tapping an individuals cheek in front of the ear by the facial nerve
-hypocalcemia
-hypomagnesemia
• trousseau's sign . CORRECT ANSWER: carpal spasm when BP cuff is inflated 20
mm Hg above systolic blood pressure for 3 minutes
-hypocalcemia
-hypomagnesemia
• hypocalcemia/hyperphosphatemia . CORRECT ANSWER: s/s: neuromuscular
excitability (muscle cramping, tetanic contractions, hyperreflexia, perioral or finger
paresthesia, positive chvosteks sign, positive trousseu's sign, seizures, shortened ST
segment and widened t wave
treatment: hypocalcemia: 1-2 ampules of 10% calcium gluconate mixed with D5W over
10 minutes
treatment: hyperphosphatemia: limit phosphate intake, oral phosphate binding agents
such as aluminum hydroxide, increased excretion (IV fluids, diuretics)
• hypercalcemia/hypophosphatemia . CORRECT ANSWER: s/s: neuromuscular
depression (decreased deep tendon reflexes, constipation, anorexia, nausea/vomiting,
Verified Questions and Answers | Most Recent
2026 Update
• hypovolemic shock . CORRECT ANSWER: decreased cellular perfusion due to lack
of circulating volume
• cardiogenic shock . CORRECT ANSWER: decreased cellular perfusion secondary to
failure of the central pump
• distributive shock . CORRECT ANSWER: decreased cellular perfusion secondary to
maldistribution of the oxygen to the periphery
• obstructive shock . CORRECT ANSWER: decreased cellular perfusion secondary to
obstruction of blood into or out of the ventricles (pulmonary embolism, pericardial
tamponade, tension pneumothorax)
• sympathetic nervous system . CORRECT ANSWER: fight or flight
adrenergic system
s/s: vasoconstriction, glycogenolysis, diaphoresis, increased HR, increased RR,
increased water and sodium reabsorption, bronchodilation
• parasympathetic nervous system . CORRECT ANSWER: rest and digest
cholinergic system
s/s: vasodilation, glucogenesis, dry skin, decreased HR, decreased respiratory rate,
bronchoconstriction
• beta one receptors . CORRECT ANSWER: -one heart, beta one affects the heart
(contractility, automaticity, heart rate)
• beta two receptors . CORRECT ANSWER: -two lungs, beta two mainly affects the
lungs (bronchodilation, respiratory rate)
• agonist . CORRECT ANSWER: stimulates a system
• antagonist . CORRECT ANSWER: diminishes system response
• hyponatremia . CORRECT ANSWER: (over hydration)
-s/s: symptoms of water retention, swelling, confusion, apathy, sense of impending
doom, muscle cramps
,-treatment: water restriction, oral sodium replacement, slow replacement with hypertonic
saline (3-5% saline solution)
-correcting too rapidly can cause central pontine myelinolysis (flaccid paralysis,
dysarthria, dysphagia, hypotension)
• hypernatremia . CORRECT ANSWER: (dehydration)
-s/s: altered mental status, fatigue, lethargy, confusion, coma, weakness, diarrhea
-treatment: correct hypovolemia, treat underlying cause (fever, vomiting, diabetes
insipidus, lower serum sodium levels (slowly replace total body water deficit)
-sodium and chloride tend to elevate and decrease together
• hyperkalemia . CORRECT ANSWER: -s/s:
early: muscular excitability, irritability, nausea, vomiting, diarrhea
late: muscular weakness, fatigue, generalized weakness, distal limb paresthesia, tetany,
respiratory depression, ascending paralysis
cardiovascular: peaked t wave, elongated PR interval, absent p wave, enlarging QRS
complex
treatment:
-stabilize cardiac membrane: calcium chloride or calcium gluconate
-shift potassium into the cells: albuterol, insulin, dextrose
-remove potassium from the cells: hemodialysis, NS and furosemide, ion exchange
resin (kayexalate)
-common causes: rental failure, cellular death (rhabdomyelosis, tumor lysis syndrome,
crush injury, burns), acidosis
• hypokalemia . CORRECT ANSWER: s/s: frequently asymptomatic, weakness,
hyporeflexia, tetany, paralysis to lower extremities, respiratory failure, prominent U wave
on EKG causing a camel hump appearance to the t wave, st depression
treatment: oral or IV potassium
-hypokalemia and hypomagnesemia often co-exist so correct magnesium with
potassium
, • hypermagnesemia . CORRECT ANSWER: s/s: neuromuscular depression, decreased
deep tendon reflex, constipation, anorexia, nausea, vomiting, fatigue, diffuse body
aches, bradycardia, hypotension, tall t waves, depressed ST segments
-treatment: reduce serum magnesium (fluids, loop diuretics) reduce ingestion of
magnesium, dialysis
• what foods contain magnesium . CORRECT ANSWER: dark leafy greens, nuts,
seeds, fish, beans, whole grains, avocados, yogurt, bananas, dried fruit, dark chocolate
• hypomagnesemia . CORRECT ANSWER: s/s: mild to moderate elevations
(asymptomatic)
-severe elevations cause neuromuscular excitability (muscular cramping, tetanic
contractions, hyperreflexia, perioral or finger paresthesia, positive chovsteks sign,
positive trousseau's sign, seizures, prolonged PR interval, widened QRS complex
-treatment: mild: oral magnesium supplements
severe: IV magnesium
• chvosteks sign . CORRECT ANSWER: twitch in the facial muscles that occurs when
tapping an individuals cheek in front of the ear by the facial nerve
-hypocalcemia
-hypomagnesemia
• trousseau's sign . CORRECT ANSWER: carpal spasm when BP cuff is inflated 20
mm Hg above systolic blood pressure for 3 minutes
-hypocalcemia
-hypomagnesemia
• hypocalcemia/hyperphosphatemia . CORRECT ANSWER: s/s: neuromuscular
excitability (muscle cramping, tetanic contractions, hyperreflexia, perioral or finger
paresthesia, positive chvosteks sign, positive trousseu's sign, seizures, shortened ST
segment and widened t wave
treatment: hypocalcemia: 1-2 ampules of 10% calcium gluconate mixed with D5W over
10 minutes
treatment: hyperphosphatemia: limit phosphate intake, oral phosphate binding agents
such as aluminum hydroxide, increased excretion (IV fluids, diuretics)
• hypercalcemia/hypophosphatemia . CORRECT ANSWER: s/s: neuromuscular
depression (decreased deep tendon reflexes, constipation, anorexia, nausea/vomiting,
