CEN Emergency Nurse practice questions with answers

Answer: B) Hypovolemia

The Hs are hypovolemia, hypoxia, hydrogen ion (acidosis), hypokalemia or hyperkalemia, and hypothermia. The Ts are tension pneumothorax, cardiac tamponade, toxins, and thrombosis (pulmonary or coronary). Hypovolemia is a classic, treatable cause of PEA.

• AIncorrect. High blood glucose is not one of the Hs. The metabolic Hs are hydrogen ion (acidosis) and hypokalemia or hyperkalemia.
• BCorrect. Hypovolemia is one of the Hs. Severe volume loss, such as from bleeding, reduces cardiac filling, so the heart has electrical activity but no pulse. Treatment is rapid volume replacement and stopping the source of the loss.
• CIncorrect. The electrolyte H is hypokalemia or hyperkalemia (potassium), not calcium.
• DIncorrect. A sodium imbalance is not one of the standard Hs and Ts.

Answer: A) Admit to continuous cardiac telemetry monitoring and obtain an echocardiogram to assess wall motion and function

Blunt cardiac injury most often shows up as dysrhythmias, including dangerous ventricular rhythms. A new dysrhythmia or elevated troponin after chest trauma calls for continuous telemetry and an echocardiogram.

• ACorrect. Suspected blunt cardiac injury with a new dysrhythmia and elevated troponin calls for continuous telemetry and echocardiography. Ventricular dysrhythmias are the most feared complication.
• BIncorrect. Elevated troponin here reflects myocardial contusion, not a coronary occlusion. Routine anticoagulation in a trauma patient may also worsen bleeding from other injuries.
• CIncorrect. The patient has none of the signs of tamponade (hypotension, distended neck veins, muffled heart sounds). Pericardiocentesis is not indicated without evidence of tamponade.
• DIncorrect. A normal ECG together with a normal troponin has a high negative predictive value for blunt cardiac injury. This patient has both a new dysrhythmia and an elevated troponin, so he needs monitoring, not discharge.

Answer: A) Spontaneous pneumothorax

• ACorrect. This is common in tall, thin young males.
• BIncorrect. Less likely in this profile.
• CIncorrect. This is a childhood illness.
• DIncorrect. Onset is sudden.

Answer: A) Cover with a 3-sided dressing

• ACorrect. A dressing taped on three sides lets air escape.
• BIncorrect. This is not a nursing action.
• CIncorrect. Cover it.
• DIncorrect. This may cause tension pneumothorax.

Answer: B) Increased intracranial pressure, such as from meningitis

A fontanelle that stays bulging when the infant is calm and upright indicates increased intracranial pressure, and with fever it suggests meningitis or encephalitis that needs emergency care. A sunken fontanelle points to dehydration instead.

• AIncorrect. Dehydration causes a sunken fontanelle, not a bulging one.
• BCorrect. A true bulging fontanelle reflects raised intracranial pressure, from causes such as meningitis, encephalitis, or hydrocephalus. With fever, it needs emergency care.
• CIncorrect. Crying, lying down, or vomiting can make a fontanelle look bulging, but it should return to normal when the infant is calm and head-up. A bulge that persists in that position is a true bulge.
• DIncorrect. Teething does not raise intracranial pressure or cause the fontanelle to bulge.

Answer: A) Compression of the right oculomotor nerve by the herniating temporal lobe

A new fixed, dilated pupil on one side in a patient with an expanding brain lesion signals uncal herniation compressing cranial nerve III. It needs immediate notification and measures to lower ICP.

• ACorrect. In uncal herniation, the medial temporal lobe presses on cranial nerve III on the same side. This cuts off parasympathetic input to the pupil and causes a fixed, dilated pupil on that side. It is an emergency, and the provider must be notified at once.
• BIncorrect. Loss of sympathetic input (Horner syndrome) makes the pupil small, not dilated.
• CIncorrect. With an afferent defect, the affected pupil still constricts when light is shone in the other eye. It does not produce a pupil that is fixed and dilated in all conditions.
• DIncorrect. Opioids make both pupils small. They do not cause a dilated, nonreactive pupil on one side.

Answer: A) Keep the patient NPO and start IV fluids and analgesia as prescribed

Initial ED care for acute cholecystitis includes NPO status, IV fluids, and prescribed analgesia (plus antibiotics as ordered) while imaging and surgical evaluation proceed.

• ACorrect. With suspected acute cholecystitis, the patient is kept NPO to rest the gallbladder and prepare for possible cholecystectomy. IV fluids and prescribed pain medication are started early.
• BIncorrect. Low-fat diet advice applies to outpatient management or recovery. During acute inflammation with possible surgery, the patient stays NPO, and diet is advanced later as tolerated.
• CIncorrect. Walking does not treat gallbladder inflammation. A febrile patient in pain needs fluids, analgesia, monitoring and surgical preparation.
• DIncorrect. Pain medication is given as prescribed. Withholding analgesia to preserve exam findings is outdated practice and leaves the patient in unnecessary pain.

Answer: B) 110 to 160 bpm

• AIncorrect. That's an adult rate.
• BCorrect. Persistent rates outside this range need evaluation.
• CIncorrect. That's too fast.
• DIncorrect. That's too slow.

Answer: A) Suicide risk may be higher during this early phase, so the nurse should screen for suicidal ideation and arrange close monitoring.

Antidepressants carry a boxed warning for more suicidal thoughts and behaviors in patients aged 24 and younger, mainly early in treatment and after dose changes. New restlessness, agitation, or insomnia should prompt suicide screening and close monitoring.

• ACorrect. The FDA boxed warning says antidepressants increase the risk of suicidal thoughts and behaviors in patients aged 24 and younger, mostly in the first few months of treatment and after dose changes. New agitation, restlessness, or insomnia are warning signs that call for suicide screening and close observation.
• BIncorrect. Energy can return before mood improves, which may give a patient the energy to act on suicidal thoughts. More energy does not mean the risk is gone.
• CIncorrect. The boxed warning covers children, adolescents, and young adults through age 24, so this 22-year-old is in the at-risk group. Patients of any age also need monitoring when starting treatment.
• DIncorrect. The risk is greatest early in treatment and after dose changes, not after long-term therapy.

Answer: D) Lorazepam to control the CNS hyperexcitability

Benzodiazepines are first-line treatment for alcohol withdrawal because they reduce symptoms and help prevent seizures and delirium tremens. Haloperidol and beta-blockers are adjuncts at most, and thiamine prevents Wernicke encephalopathy but does not treat withdrawal.

• AIncorrect. Antipsychotics such as haloperidol can lower the seizure threshold and do not prevent withdrawal seizures or delirium tremens. If used at all, they are cautious adjuncts, not primary treatment.
• BIncorrect. Beta-blockers can reduce heart rate and blood pressure, but they do not prevent seizures or delirium and give only modest symptom relief. They are adjuncts at most and can hide worsening withdrawal.
• CIncorrect. Thiamine is given to prevent or treat Wernicke encephalopathy. It does not treat the CNS hyperexcitability of withdrawal or prevent seizures and delirium tremens.
• DCorrect. Benzodiazepines such as lorazepam or diazepam enhance GABA activity. They are the drug class of choice for alcohol withdrawal because they relieve symptoms and help prevent withdrawal seizures and delirium tremens.

Answer: D) Cerebral edema

• AIncorrect. These are warning signs.
• BIncorrect. These are warning signs.
• CIncorrect. Cerebral edema must be considered.
• DCorrect. It's a dangerous complication.

Answer: A) The narrow, sharp teeth push oral bacteria such as Pasteurella multocida deep into tissue, so infection is common

Cat bites usually cause deep puncture wounds that carry oral bacteria, especially Pasteurella multocida, into deep tissue, so infection rates are high. Oral amoxicillin-clavulanate is the first-line antibiotic, and rabies and tetanus status are also assessed.

• ACorrect. Cat bites usually cause deep puncture wounds. Pasteurella species are cultured from about 75% of cat bite wounds, and infection often appears within 24 hours. Hand bites can reach joints and bone. Oral amoxicillin-clavulanate is the first-line choice for prophylaxis and treatment.
• BIncorrect. Cat saliva has no neurotoxin. The danger comes from bacteria pushed deep into tissue, and rabies risk is assessed separately.
• CIncorrect. Crush injuries are more typical of large-dog bites. Cat bites cause small, deep puncture wounds where infection is the main concern.
• DIncorrect. Tetanus status should be updated after any bite, but cat bites are not a leading cause of tetanus. The high-risk feature is deep bacterial infection, often with Pasteurella.

Answer: B) Advocate for prompt provider evaluation and audiometry, because corticosteroid therapy is most effective when it is started early

Sudden one-sided hearing loss with a normal ear exam suggests sudden sensorineural hearing loss and needs prompt evaluation, including a hearing test. Corticosteroids are most effective when started early, and delays of more than 2–4 weeks reduce the chance of recovery.

• AIncorrect. Some patients do recover on their own, but delaying diagnosis and treatment makes treatment less effective. Treatment delayed more than 2–4 weeks is less likely to restore hearing.
• BCorrect. Sudden unexplained one-sided hearing loss with a normal ear exam suggests sudden sensorineural hearing loss. This is treated as urgent. Corticosteroids are the most common treatment and work best when started as soon as possible.
• CIncorrect. The canal is clear, so cerumen impaction is not the cause. Irrigating would delay evaluation for a sensorineural cause.
• DIncorrect. There is no pain, drainage, or canal inflammation to suggest otitis externa. Antibiotic drops do not treat sensorineural hearing loss.

Answer: B) Airborne infection isolation room; staff wear a fit-tested N95 or higher-level respirator on entry

Suspected measles calls for Airborne Precautions right away: an AIIR and an N95-or-better respirator for all staff, whatever their immunity status. Precautions usually continue for 4 days after rash onset, or for the whole illness if the patient is immunocompromised.

• AIncorrect. This describes Droplet Precautions. Measles spreads through the air, so a surgical mask and an ordinary private room do not protect staff or other patients.
• BCorrect. CDC says to place a patient with known or suspected measles in an AIIR right away. Staff should wear a respirator at least as protective as a fit-tested N95 when entering, even if they have presumptive evidence of immunity.
• CIncorrect. Measles is not mainly a contact-spread disease. CDC recommends that staff wear a respirator whether or not they have evidence of immunity.
• DIncorrect. A curtained bay does not contain airborne virus. Putting a mask on the patient does not replace an AIIR, and precautions are timed from rash onset, not from when the rash fades.

Answer: A) Provide the greatest good for the greatest number of patients

When resources are overwhelmed in a mass casualty event, triage shifts from what's best for each individual patient to the greatest good for the greatest number. As a result, patients who are expected to die may not be treated first.

• ACorrect. Mass casualty triage aims to give the greatest good to the greatest number of people when healthcare resources are limited or strained.
• BIncorrect. In a mass casualty event, patients whose injuries are incompatible with life are tagged expectant (black). Scarce resources go first to patients who are likely to benefit, not simply to those who are most injured.
• CIncorrect. Routine triage focuses on comprehensive care for each patient. Mass casualty triage limits treatment during the first assessment and focuses on rapid sorting for the benefit of the whole group.
• DIncorrect. Treating patients in arrival order doesn't account for how urgent their needs are or whether they are likely to survive. Mass casualty triage relies on rapid sorting, not first-come, first-served care.