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Question 1Cardiovascular Emergencies

A 12-lead ECG obtained during crushing chest pain shows ST-segment elevation in leads V2 and V3. These findings most directly indicate injury to which area of the heart?

  1. Posterior wall
  2. Lateral wall
  3. Inferior wall
  4. Anterior wall Correct answer.

Explanation

Leads V1 through V4 view the anterior wall, so ST elevation in V2 and V3 localizes injury to the anterior/anteroseptal region. Inferior injury appears in II, III, and aVF, while lateral injury appears in I, aVL, V5, and V6. Posterior injury is suggested by reciprocal ST depression in V1 through V3.

Question 2Cardiovascular Emergencies

A patient with suspected acute coronary syndrome has no allergies and has not taken any medications today. Which intervention should be given first?

  1. IV morphine sulfate
  2. Oral metoprolol
  3. Chewed aspirin 162 to 325 mg Correct answer.
  4. Sublingual nitroglycerin

Explanation

Chewed non-enteric-coated aspirin is the earliest pharmacologic priority in suspected ACS because it rapidly inhibits platelet aggregation and reduces mortality. Nitrates, opioids, and beta-blockers relieve symptoms or reduce demand but do not carry the same early mortality benefit. Aspirin should be given unless a true allergy or active bleeding exists.

Question 3Cardiovascular Emergencies

Which finding is an absolute contraindication to sublingual nitroglycerin?

  1. PDE5 inhibitor use within 24 hours Correct answer.
  2. Blood pressure of 150/90 mm Hg at rest
  3. Heart rate of 110/min
  4. Age greater than 65 years

Explanation

Phosphodiesterase-5 inhibitors markedly potentiate nitrate-induced vasodilation, so combining them can cause refractory hypotension. Nitrates are withheld within 24 hours of sildenafil or vardenafil and within 48 hours of tadalafil. Tachycardia, mild hypertension, and advanced age are not contraindications by themselves.

Question 4Cardiovascular Emergencies

Which set of findings best describes cardiogenic shock?

  1. Warm skin, bounding pulses, and a low systemic vascular resistance
  2. Hypertension with bradycardia and a widened pulse pressure
  3. Normal blood pressure with isolated elevation of the heart rate
  4. Hypotension with cool, clammy skin and poor end-organ perfusion Correct answer.

Explanation

Cardiogenic shock results from pump failure, producing low cardiac output with compensatory vasoconstriction. Patients are hypotensive with cool, mottled skin, delayed capillary refill, altered mentation, and oliguria. Warm flushed skin with low vascular resistance describes distributive shock instead.

Question 5Cardiovascular Emergencies

An adult in cardiac arrest is in ventricular fibrillation, CPR is in progress, and the monitor is attached. What is the next intervention?

  1. Perform synchronized cardioversion
  2. Give amiodarone 300 mg IV
  3. Defibrillate with a single shock Correct answer.
  4. Give epinephrine 1 mg IV

Explanation

Ventricular fibrillation is a shockable rhythm, and defibrillation is the definitive treatment that should be delivered as soon as it is available. Epinephrine and amiodarone are given after the first shock during the CPR cycle. Synchronized cardioversion is used only for organized rhythms with a pulse.

Question 6Cardiovascular Emergencies

A patient is confused and hypotensive with a heart rate of 38/min, and no IV access has been obtained. Which intervention is indicated?

  1. Synchronized cardioversion at 100 J
  2. Defibrillation at 200 J
  3. Transcutaneous pacing Correct answer.
  4. Adenosine 6 mg rapid IV push

Explanation

Symptomatic bradycardia with hypotension and altered mental status requires pacing when atropine is ineffective or access is unavailable. Transcutaneous pacing can be started immediately through the monitor pads while IV access is being established. Cardioversion and defibrillation treat tachyarrhythmias, not bradycardia.

Question 7Cardiovascular Emergencies

Which intervention most directly improves oxygenation and reduces preload in a patient with acute cardiogenic pulmonary edema?

  1. High-flow oxygen by nasal cannula alone
  2. Placing the patient in Trendelenburg position
  3. An IV fluid bolus of 500 mL
  4. Continuous positive airway pressure Correct answer.

Explanation

Continuous positive airway pressure stents open flooded alveoli, improves oxygenation, and increases intrathoracic pressure to reduce venous return and preload. It may also decrease the work of breathing and avoid intubation. Supplemental oxygen alone does not address the fluid-filled alveoli or the elevated preload.

Question 8Cardiovascular Emergencies

Which rhythm is treated with high-quality CPR and epinephrine and is never defibrillated?

  1. Sinus tachycardia with a pulse
  2. Asystole Correct answer.
  3. Pulseless ventricular tachycardia
  4. Ventricular fibrillation

Explanation

Asystole is a non-shockable arrest rhythm managed with continuous CPR, epinephrine, and a search for reversible causes. Shockable arrest rhythms are ventricular fibrillation and pulseless ventricular tachycardia. Attempting to defibrillate asystole provides no benefit and interrupts compressions.

Question 9Cardiovascular Emergencies

A 45-year-old has palpitations, a regular narrow-complex tachycardia at 190/min, and a blood pressure of 118/72 mm Hg. Vagal maneuvers have failed. Which intervention is most appropriate next?

  1. Amiodarone 150 mg IV over 10 minutes
  2. Synchronized cardioversion at 50 J
  3. Adenosine 6 mg rapid IV push with a saline flush Correct answer.
  4. Diltiazem 20 mg IV push over two minutes

Explanation

A stable patient with a regular narrow-complex tachycardia that persists after vagal maneuvers is treated with adenosine, which briefly blocks the AV node and can terminate AV nodal reentrant tachycardias. It must be given as a rapid push followed immediately by a saline flush because of its very short half-life. Cardioversion is reserved for unstable patients.

Question 10Cardiovascular Emergencies

A patient has a wide-complex tachycardia at 220/min, a blood pressure of 78/40 mm Hg, and altered mental status, with a palpable pulse. Which intervention is most appropriate?

  1. Synchronized cardioversion Correct answer.
  2. Adenosine 6 mg rapid IV push
  3. Amiodarone 150 mg IV bolus
  4. Vagal maneuvers

Explanation

An unstable tachycardia with a pulse is treated with immediate synchronized cardioversion to restore an organized rhythm and perfusion. Adenosine, antiarrhythmics, and vagal maneuvers are considered only for stable patients. Sedation should be given if the patient's condition permits.

Question 11Cardiovascular Emergencies

A patient reports sudden tearing chest pain radiating to the back, with a blood pressure of 180/100 mm Hg in the right arm and 140/80 mm Hg in the left arm. Which condition best fits these findings?

  1. Acute pericarditis
  2. Inferior wall STEMI
  3. Aortic dissection Correct answer.
  4. Pulmonary embolism

Explanation

Tearing pain radiating to the back with an interarm blood pressure difference and unequal pulses is the classic presentation of aortic dissection. The dissection flap can compromise branch vessels, producing pulse deficits and neurologic or renal findings. Immediate blood pressure control and surgical or endovascular consultation are priorities.

Question 12Cardiovascular Emergencies

A trauma patient has hypotension, distended neck veins, and muffled heart sounds. Which additional finding best supports cardiac tamponade?

  1. Absent breath sounds over one hemithorax
  2. Pulsus paradoxus greater than 10 mm Hg Correct answer.
  3. Bradycardia with severe hypertension
  4. Tracheal deviation away from the injured side

Explanation

Beck triad (hypotension, jugular venous distention, and muffled heart sounds) suggests tamponade, and pulsus paradoxus supports the diagnosis by showing exaggerated inspiratory decline in systolic pressure. Pericardial fluid restricts filling, so stroke volume falls with inspiration. Treatment is fluid administration and emergency pericardiocentesis.

Question 13Cardiovascular Emergencies

Which feature most strongly suggests acute pericarditis rather than acute myocardial infarction?

  1. ST elevation limited to two contiguous leads with reciprocal changes
  2. New left bundle branch block with a normal troponin
  3. Pain that is pleuritic and eased by leaning forward Correct answer.
  4. Pain that is relieved by rest and sublingual nitroglycerin

Explanation

Pericardial pain is typically pleuritic and improves when the patient sits up and leans forward because the inflamed surfaces separate. Infarction pain is pressure-like, related to exertion, and relieved by rest or nitrates. Pericarditis also tends to produce diffuse ST elevation with PR depression rather than focal changes.

Question 14Cardiovascular Emergencies

Which presentation most suggests a massive pulmonary embolism?

  1. Sharp chest pain that worsens with inspiration and eases when upright
  2. Sudden dyspnea, hypotension, and distended neck veins Correct answer.
  3. Bilateral basilar crackles with pink, frothy sputum
  4. Unilateral leg swelling with a normal oxygen saturation

Explanation

A large embolus obstructs right ventricular outflow, causing acute right heart failure with hypotension, jugular venous distention, and hypoxemia. These patients are at high risk for pulseless electrical activity arrest. Anticoagulation plus consideration of thrombolysis or embolectomy is indicated for hemodynamic instability.

Question 15Cardiovascular Emergencies

A patient has a blood pressure of 210/120 mm Hg with chest pain and ST depression on the ECG. Which management approach is correct?

  1. Gradual IV reduction of MAP by no more than 25% in the first hour Correct answer.
  2. No treatment unless the blood pressure exceeds 220/120 mm Hg
  3. Oral captopril followed by reassessment in one hour
  4. Rapid reduction of the blood pressure to normal within 15 minutes

Explanation

Hypertensive emergency with target-organ damage requires controlled IV blood pressure lowering, generally limiting the mean arterial pressure reduction to about 25% in the first hour. Rapid normalization can cause cerebral, coronary, or renal hypoperfusion. Oral agents are too unpredictable for an emergency presentation.

Question 16Cardiovascular Emergencies

Which cluster of findings is most characteristic of digoxin toxicity?

  1. Yellow-green visual halos with nausea and bradycardia Correct answer.
  2. Peaked P waves with a shortened PR interval
  3. Prolonged QT interval with polymorphic ventricular tachycardia
  4. Widened QRS complexes with peaked T waves

Explanation

Digoxin toxicity classically causes gastrointestinal upset, visual disturbances such as yellow-green halos, and bradyarrhythmias or heart block. Hyperkalemia often accompanies acute toxicity and predicts severity. Treatment includes correcting electrolytes, holding the drug, and using digoxin-specific antibody fragments for life-threatening cases.

Question 17Cardiovascular Emergencies

A patient with atrial fibrillation has a heart rate of 148/min and a blood pressure of 132/80 mm Hg, with no chest pain, dyspnea, or altered mentation. What is the most appropriate initial management?

  1. Adenosine 6 mg rapid IV push
  2. Rate control with an IV beta-blocker or diltiazem Correct answer.
  3. Defibrillation at 200 J
  4. Immediate synchronized cardioversion at 100 J

Explanation

A stable patient with atrial fibrillation and rapid ventricular response is managed initially with rate control using a beta-blocker or a nondihydropyridine calcium channel blocker. Electrical cardioversion is reserved for unstable patients or for those with a contraindication to pharmacologic rate control. Adenosine does not slow the ventricular rate in atrial fibrillation.

Question 18Cardiovascular Emergencies

An ECG shows regular P waves at 90/min and a wide-complex ventricular rhythm at 32/min, with no consistent relationship between the P waves and the QRS complexes. How should this be interpreted?

  1. Atrial fibrillation with a slow ventricular response
  2. Second-degree AV block, type I
  3. Sinus bradycardia with premature ventricular complexes
  4. Third-degree (complete) AV block Correct answer.

Explanation

Complete AV block produces atrioventricular dissociation, with atrial and ventricular rates that are independent of each other. The ventricular escape rhythm is slow and often wide, and the patient may need transcutaneous pacing. Type I second-degree block shows progressive PR prolongation with dropped beats rather than complete dissociation.

Question 19Cardiovascular Emergencies

A 72-year-old has sudden severe abdominal and back pain, a blood pressure of 88/60 mm Hg, and a pulsatile abdominal mass. What is the priority action?

  1. Notify the surgeon and prepare for emergent repair Correct answer.
  2. Apply a compression binder and obtain a portable abdominal x-ray
  3. Administer a 1-L normal saline bolus and observe for two hours
  4. Give nitroglycerin for pain control and reassess in 30 minutes

Explanation

A pulsatile abdominal mass with hypotension and severe back pain indicates a ruptured abdominal aortic aneurysm, which is a surgical emergency. The patient needs large-bore IV access, blood product availability, and immediate operative or endovascular repair. Diagnostic delays increase mortality substantially.

Question 20Cardiovascular Emergencies

After return of spontaneous circulation, a comatose patient has ST elevation on the ECG. Which management approach is correct?

  1. Delay PCI until the patient is awake and following commands
  2. Maintain a mean arterial pressure below 50 mm Hg to reduce bleeding
  3. Target an SpO2 of 100% and hyperventilate to lower the PaCO2
  4. Keep SpO2 at 92% to 98% and arrange emergent coronary angiography Correct answer.

Explanation

Post-arrest care avoids both hypoxemia and hyperoxia, so oxygen is titrated to an SpO2 of roughly 92% to 98%, and ventilation targets a normal PaCO2. Comatose survivors with ST elevation should undergo emergent coronary angiography because reperfusion improves outcomes. Hypotension and hyperventilation both worsen cerebral perfusion.

Question 21Cardiovascular Emergencies

Three days after an inferior myocardial infarction, a patient develops sudden dyspnea, hypotension, and a new loud holosystolic murmur at the apex radiating to the axilla. What is the most likely cause?

  1. Ventricular septal rupture producing a left-to-right shunt
  2. Recurrent myocardial ischemia without mechanical complication
  3. Free wall rupture causing cardiac tamponade
  4. Papillary muscle rupture causing acute mitral regurgitation Correct answer.

Explanation

Inferior infarction can infarct the posteromedial papillary muscle, producing acute mitral regurgitation with a new apical holosystolic murmur radiating to the axilla and rapid pulmonary edema. This is a mechanical complication requiring urgent surgical repair. Septal rupture also causes a holosystolic murmur but it is loudest at the left sternal border and produces a shunt rather than severe regurgitation.

Question 22Cardiovascular Emergencies

A patient with a prolonged QT interval who takes multiple QT-prolonging medications develops polymorphic ventricular tachycardia and still has a palpable pulse. Which is the first-line drug treatment?

  1. Amiodarone 150 mg IV over 10 minutes
  2. Synchronized cardioversion at 50 J
  3. Procainamide infusion at 20 mg/min
  4. IV magnesium sulfate Correct answer.

Explanation

Torsades de pointes is treated with IV magnesium, which stabilizes the myocardium even when the serum magnesium level is normal. Offending QT-prolonging drugs should be stopped and electrolytes corrected. Antiarrhythmics such as amiodarone and procainamide prolong the QT further and can worsen the rhythm.

Question 23Cardiovascular Emergencies

Which presentation is most consistent with severe beta-blocker overdose?

  1. Wide QRS complexes that respond to sodium bicarbonate
  2. Bradycardia, hypotension, and hypoglycemia Correct answer.
  3. Hypertension, tachycardia, and dilated pupils
  4. Hyperthermia with severe muscle rigidity

Explanation

Beta-blocker toxicity produces bradycardia, hypotension, and hypoglycemia because beta-adrenergic stimulation of the heart and of glycogenolysis is blocked. Treatment includes fluids, glucagon, high-dose insulin with dextrose, and vasopressors. Sodium bicarbonate is used for sodium channel blockade from tricyclic antidepressants.

Question 24Cardiovascular Emergencies

A patient with a left ventricular assist device is unresponsive with no palpable pulse. What should be done first?

  1. Defibrillate at 200 J before assessing the device
  2. Withhold all resuscitative efforts because the device is running
  3. Begin chest compressions immediately at 100/min
  4. Check the controller, listen for the pump hum, and review alarms Correct answer.

Explanation

Continuous-flow devices often produce no palpable pulse, so assessment must include listening for the pump hum, checking the controller and driveline, and reviewing alarms before concluding the patient is pulseless. Compressions can dislodge the inflow cannula, so they are started only when the device is not functioning and the patient has no perfusion. Defibrillation is still used for shockable rhythms when indicated.

Question 25Cardiovascular Emergencies

A patient with an inferior STEMI becomes markedly hypotensive after receiving sublingual nitroglycerin. What is the most likely explanation?

  1. A new ventricular septal defect with left-to-right shunting
  2. Acute mitral regurgitation from papillary muscle rupture
  3. Right ventricular infarction with preload dependence Correct answer.
  4. An anaphylactic reaction to nitroglycerin

Explanation

Inferior infarction often involves the right ventricle, which becomes dependent on venous return to maintain output. Nitrates cause venodilation and drop preload, producing severe hypotension in these patients. Management includes fluids and avoiding nitrates, and a right-sided ECG can confirm right ventricular involvement.

Question 26Cardiovascular Emergencies

ST-segment elevation in leads II, III, and aVF most directly indicates infarction of which region of the heart?

  1. Inferior wall, most often from right coronary artery occlusion Correct answer.
  2. Posterior wall, most often from left anterior descending artery occlusion
  3. Anterior wall, most often from left anterior descending artery occlusion
  4. Lateral wall, most often from left circumflex artery occlusion

Explanation

Leads II, III, and aVF look at the inferior surface of the left ventricle, so ST elevation in this grouping defines an inferior injury pattern. The right coronary artery supplies the inferior wall in most people, which is why these patients are also screened for right ventricular involvement and bradyarrhythmias. Anterior injury appears in the precordial leads V1 through V4, and lateral injury appears in I, aVL, V5, and V6.

Question 27Cardiovascular Emergencies

A 62-year-old reports 40 minutes of substernal pressure. The 12-lead ECG shows no ST elevation, and the patient has no medication allergies. Which early intervention most reduces mortality in suspected acute coronary syndrome?

  1. Chewed non-enteric-coated aspirin 162 to 325 mg Correct answer.
  2. High-flow oxygen by nonrebreather for every patient with chest pain
  3. Sublingual nitroglycerin repeated every 5 minutes until the pain is gone
  4. IV morphine sulfate titrated for pain control

Explanation

Chewed aspirin produces rapid platelet inhibition and is the single early drug that consistently lowers mortality across the spectrum of acute coronary syndrome, so it is given unless a true allergy or active bleeding exists. Nitrates, opioids, and oxygen relieve symptoms or treat specific complications but do not carry the same mortality benefit. Oxygen is reserved for hypoxemia rather than given routinely.

Question 28Cardiovascular Emergencies

A 58-year-old with 2 hours of chest pressure is diaphoretic with a blood pressure of 118/70 mm Hg. The ECG shows ST depression in leads V1 through V3 with tall R waves and upright T waves in those same leads. What do these findings most likely represent?

  1. Left ventricular hypertrophy with a repolarization abnormality
  2. Anterior subendocardial ischemia that should be managed as unstable angina
  3. A normal variant pattern that requires no further cardiac workup
  4. Posterior myocardial infarction that warrants reperfusion therapy Correct answer.

Explanation

ST depression with tall R waves and upright T waves in V1 through V3 is the mirror image of posterior injury, produced when leads placed on the anterior chest look at the infarct from the opposite side. This pattern is treated as a STEMI equivalent, so reperfusion therapy and cardiology consultation should proceed promptly. Reciprocal ST depression is a common reason posterior infarction is missed when it is read simply as anterior ischemia.

Question 29Respiratory Emergencies

A patient in acute asthma exacerbation has diffuse wheezing and moderate distress. Which medication should be given first?

  1. Inhaled albuterol Correct answer.
  2. IV methylprednisolone
  3. Inhaled ipratropium
  4. IM epinephrine

Explanation

Short-acting beta-2 agonists such as albuterol relax bronchial smooth muscle within minutes and are the first-line therapy for acute bronchospasm. Ipratropium and corticosteroids are added for severe or persistent symptoms but do not produce the initial rapid bronchodilation. IM epinephrine is reserved for impending respiratory arrest or anaphylaxis.

Question 30Respiratory Emergencies

A patient with chronic obstructive pulmonary disease has an SpO2 of 86% on room air and is in mild distress. What oxygen saturation range should be targeted?

  1. 98% to 100%
  2. 84% to 86%
  3. 94% to 98%
  4. 88% to 92% Correct answer.

Explanation

In COPD, oxygen is titrated to an SpO2 of 88% to 92% because over-oxygenation can worsen hypercapnia through loss of hypoxic vasoconstriction and the Haldane effect. This range corrects hypoxemia while avoiding carbon dioxide retention. Higher targets are used for most other conditions.

Question 31Respiratory Emergencies

Which set of findings identifies a tension pneumothorax rather than a simple pneumothorax?

  1. Pleuritic chest pain with a dry cough
  2. Hyperresonance to percussion
  3. Absent breath sounds on the affected side
  4. Hypotension with tracheal deviation Correct answer.

Explanation

Tension pneumothorax causes obstructive shock, so hypotension, distended neck veins, and tracheal deviation away from the affected side are the distinguishing features. Simple pneumothorax produces absent breath sounds and hyperresonance without hemodynamic collapse. Hypotension with tracheal shift requires immediate decompression.

Question 32Respiratory Emergencies

A patient with acute decompensated heart failure has crackles to the apices, orthopnea, and copious pink, frothy sputum. Which process does the sputum indicate?

  1. Bacterial pneumonia
  2. Upper gastrointestinal bleeding
  3. Acute pulmonary edema Correct answer.
  4. Pulmonary embolism

Explanation

Pink, frothy sputum results from fluid transudation into the alveoli that is agitated by air movement, marking severe pulmonary edema. It correlates with hypoxemia and requires aggressive oxygenation and ventilatory support. Blood from other sources is not frothy.

Question 33Respiratory Emergencies

A 44-year-old who had knee replacement surgery three days ago reports sudden dyspnea and pleuritic chest pain. Vital signs are HR 118, BP 108/70, RR 30, SpO2 89% on room air. Which condition is most likely?

  1. Pulmonary embolism Correct answer.
  2. Spontaneous pneumothorax
  3. Bacterial pneumonia
  4. Acute pericarditis

Explanation

Recent major orthopedic surgery, sudden dyspnea, pleuritic pain, tachycardia, and hypoxemia form the classic presentation of pulmonary embolism. Immobility promotes deep vein thrombosis that embolizes to the pulmonary vasculature. Pneumonia usually develops fever and productive cough over days rather than sudden onset.

Question 34Respiratory Emergencies

Which oxygen delivery device provides the highest fraction of inspired oxygen?

  1. Venturi mask at 40 percent
  2. Nasal cannula at 6 L/min
  3. Nonrebreather mask at 15 L/min Correct answer.
  4. Simple face mask at 10 L per minute

Explanation

A nonrebreather mask with a reservoir bag and one-way valves delivers approximately 90% to 100% oxygen at 10 to 15 L/min. Simple masks and nasal cannulas deliver far lower concentrations, and Venturi masks deliver a fixed low-to-moderate concentration.

Question 35Respiratory Emergencies

A patient with blunt chest trauma has several fractured ribs on the left. Which finding indicates flail chest?

  1. Paradoxical inward movement of the flail segment Correct answer.
  2. Tracheal deviation toward the injured side
  3. Asymmetric chest rise from splinting on the injured side
  4. Subcutaneous emphysema at the fracture site

Explanation

Flail chest occurs when two or more adjacent ribs fracture in two or more places, creating a free segment that moves inward during inspiration and outward during expiration. This paradoxical motion impairs ventilation and often accompanies pulmonary contusion. Splinting alone does not define a flail segment.

Question 36Respiratory Emergencies

A patient in status asthmaticus who was wheezing loudly now has minimal breath sounds and a quiet chest. What does this change indicate?

  1. Retained secretions have cleared the airways
  2. A pneumothorax has developed
  3. The patient is improving and the wheeze has resolved
  4. Airflow is too low to produce a wheeze Correct answer.

Explanation

A silent chest means air movement is so severely reduced that wheezing cannot be generated, which signals impending respiratory failure. It is an ominous finding, not improvement, and requires immediate aggressive therapy and preparation for intubation.

Question 37Respiratory Emergencies

A patient with a COPD exacerbation is alert and cooperative. ABG shows pH 7.28, PaCO2 68 mm Hg, and PaO2 58 mm Hg. Which intervention is most appropriate?

  1. Give intravenous sodium bicarbonate bolus
  2. Intubate the trachea without a trial of NIV
  3. Apply a nonrebreather mask at 15 L/min
  4. Noninvasive positive-pressure ventilation Correct answer.

Explanation

Noninvasive positive-pressure ventilation reduces work of breathing and improves gas exchange in COPD exacerbations with hypercapnic acidosis, and it lowers mortality and intubation rates when the patient is alert and cooperative. Endotracheal intubation is reserved for failure of NIV or inability to protect the airway. High-concentration oxygen may worsen hypercapnia.

Question 38Respiratory Emergencies

A chest tube is placed for a hemothorax. Which finding should be reported to the provider immediately?

  1. Sudden return of 1500 mL of blood Correct answer.
  2. Dark red drainage that appears in the tubing
  3. Serous drainage of 100 mL during the first shift
  4. Continuous bubbling in the water-seal chamber

Explanation

Sudden drainage of more than 1000 to 1500 mL of blood, or ongoing bleeding greater than 200 mL per hour, suggests active intrathoracic hemorrhage and possible need for thoracotomy. Large-volume return also warrants volume resuscitation and urgent surgical evaluation.

Question 39Respiratory Emergencies

A patient with a stab wound has absent breath sounds on the right, distended neck veins, BP 74/40, and tracheal deviation to the left. Which action should the nurse anticipate?

  1. Immediate needle decompression Correct answer.
  2. Arrange a CT scan before chest tube placement
  3. Obtain a chest radiograph before treatment
  4. Prepare for pericardiocentesis

Explanation

These findings indicate tension pneumothorax with obstructive shock, which is a clinical diagnosis requiring immediate needle decompression followed by tube thoracostomy. Waiting for imaging delays treatment and increases the risk of cardiac arrest. Pericardiocentesis is considered when pericardial tamponade is suspected instead.

Question 40Respiratory Emergencies

Which finding is characteristic of acute respiratory distress syndrome?

  1. Increased wedge pressure with cardiomegaly
  2. Refractory hypoxemia with bilateral infiltrates Correct answer.
  3. Unilateral hyperresonance with absent breath sounds
  4. Wheezing that clears with albuterol

Explanation

ARDS causes noncardiogenic pulmonary edema with bilateral infiltrates and severe hypoxemia that responds poorly to supplemental oxygen because of intrapulmonary shunting. Cardiac filling pressures are normal, distinguishing it from cardiogenic pulmonary edema.

Question 41Respiratory Emergencies

Immediately after endotracheal intubation, the capnography tracing is flat and the end-tidal CO2 is 0 mm Hg. What is the most likely cause?

  1. Hyperventilation
  2. Mucus in the endotracheal tube
  3. Severe bronchospasm
  4. Esophageal intubation Correct answer.

Explanation

Absent end-tidal CO2 after intubation most often means the tube is in the esophagus, because no carbon dioxide is exchanged in the esophagus. The tube should be removed and the airway re-established with bag-mask ventilation before another attempt. Bronchospasm and mucus produce abnormal but present waveforms.

Question 42Respiratory Emergencies

What is the maximum recommended duration for each suction pass through an endotracheal tube?

  1. 5 seconds
  2. 10 to 15 seconds Correct answer.
  3. 45 seconds
  4. 20 to 30 seconds

Explanation

Suction passes should be limited to 10 to 15 seconds because suctioning removes both secretions and oxygen, and prolonged passes cause hypoxemia, bradycardia, and atelectasis. Preoxygenation with 100% oxygen before and after the pass reduces these risks.

Question 43Respiratory Emergencies

A patient with smoke inhalation has an SpO2 of 99% but is confused and has cherry-red skin. What best explains the pulse oximetry reading?

  1. Carboxyhemoglobin is read as oxyhemoglobin Correct answer.
  2. Methemoglobin is being measured
  3. The value reflects severe anemia
  4. Adequate perfusion confirms normal oxygenation

Explanation

Standard pulse oximeters cannot distinguish carboxyhemoglobin from oxyhemoglobin, so readings appear falsely normal or high in carbon monoxide poisoning. Oxygen content is actually severely reduced, and treatment requires high-concentration oxygen or hyperbaric therapy. Clinical signs and co-oximetry are needed for diagnosis.

Question 44Respiratory Emergencies

An older adult with three rib fractures is splinting and taking shallow breaths. Which intervention best prevents atelectasis?

  1. Restrict oral fluids to reduce work
  2. Apply a tight binder around the chest
  3. Analgesia plus incentive spirometry Correct answer.
  4. Maintain strict bed rest for 48 hours

Explanation

Adequate pain control allows deep breathing and coughing, and incentive spirometry plus early mobilization are the mainstays of preventing atelectasis and pneumonia after rib fractures. Chest binders and bed rest reduce lung expansion and increase complications.

Question 45Respiratory Emergencies

Which presentation is most typical of pneumonia in an 82-year-old patient?

  1. Sudden hemoptysis with pleuritic pain
  2. Acute confusion with low-grade fever Correct answer.
  3. High fever with shaking chills and rigors
  4. Bradycardia with hypertension

Explanation

Older adults often mount a blunted immune response, so pneumonia presents with confusion, malaise, and minimal or absent fever rather than classic chills and high fever. New confusion in an older adult should prompt evaluation for infection.

Question 46Respiratory Emergencies

A patient with a tracheostomy is in respiratory distress with no air movement through the tube. Which action is correct?

  1. Increase humidification and reassess in 10 minutes
  2. Deflate the cuff and ventilate with a bag-valve mask over the mouth
  3. Instill 10 mL of normal saline and suction the airway
  4. Remove the inner cannula and suction the stoma Correct answer.

Explanation

When a tracheostomy is obstructed, the inner cannula should be removed and the stoma suctioned, and the tube replaced with a same-size tube if obstruction persists. Deflating the cuff does not relieve an obstructed tube, and occluding the stoma during bag-mask ventilation may be necessary if the tube cannot be cleared.

Question 47Respiratory Emergencies

An ABG shows pH 7.30, PaCO2 55 mm Hg, and HCO3 26 mEq/L. How should this be interpreted?

  1. Respiratory alkalosis
  2. Metabolic alkalosis
  3. Metabolic acidosis with compensation
  4. Acute respiratory acidosis Correct answer.

Explanation

An elevated PaCO2 with a low pH indicates respiratory acidosis, and a normal bicarbonate level shows that renal compensation has not yet occurred, making it acute. Compensation would raise the bicarbonate over days.

Question 48Respiratory Emergencies

A patient receiving positive-pressure ventilation suddenly develops rising peak airway pressures, hypotension, and absent breath sounds on the left. Which action is the priority?

  1. Increase the PEEP setting
  2. Obtain a portable chest radiograph first
  3. Suction the endotracheal tube
  4. Needle decompression of the chest Correct answer.

Explanation

Positive-pressure ventilation can convert a simple pneumothorax into a tension pneumothorax, producing sudden rising airway pressures, hypotension, and unilateral absent breath sounds. This is a clinical emergency requiring immediate needle decompression followed by tube thoracostomy. Imaging and ventilator changes delay definitive treatment.

Question 49Respiratory Emergencies

Which ventilator strategy is recommended for a patient with ARDS?

  1. High tidal volumes with zero PEEP
  2. FiO2 of 1.0 maintained indefinitely
  3. 6 mL/kg predicted body weight tidal volumes Correct answer.
  4. 12 mL/kg tidal volumes with peak pressures to 50 cm H2O

Explanation

Lung-protective ventilation uses low tidal volumes of about 6 mL/kg of predicted body weight with plateau pressures kept at or below 30 cm H2O to prevent volutrauma and barotrauma. PEEP is titrated to maintain recruitment and oxygenation. High tidal volumes and sustained 100% oxygen worsen lung injury.

Question 50Respiratory Emergencies

A patient with status asthmaticus has just been intubated. Which ventilation strategy reduces the risk of air trapping?

  1. High respiratory rate with a shortened expiratory time
  2. Zero PEEP with 100% oxygen
  3. Low respiratory rate with a prolonged expiratory time Correct answer.
  4. Large tidal volumes to overcome resistance

Explanation

Severe bronchospasm prolongs expiration, so a low respiratory rate with a long expiratory time allows complete exhalation and prevents dynamic hyperinflation and barotrauma. Permissive hypercapnia is accepted to protect the lungs. High rates and large tidal volumes worsen gas trapping.