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CCRN Exam with Questions and Verified Solutions A patient has had a large anterior myocardial infarction last month and developed a ventricular aneurysm. He now has episodes of ventricular tachycardia that are not prevented or converted with antidysrhythmic agents. An implantable cardioverter-defibrillator (ICD) is implanted. Four days after surgery he develops ventricular tachycardia. The ICD has delivered three shocks but has not converted the rhythm. He is pulseless and apneic. Cardiopulmonary resuscitation is in progress. What is the priority action now? A Administer epinephrine IV. B. Administer amiodarone. Cc. Defibrillate. D. Reset the ICD. ANSWERV ¥ Defibrillate A 28-year-old woman is admitted to the critical care unit from the emergency department with a diagnosis of asthma. Her initial arterial blood gases on a 28% Venturi mask are as follows: pH 7.48 PaCO2 30 mm Hg TICO3 24 mEq/L PaOQ2 64 mm Hg Which of the following repeat arterial blood gases on 40% oxygen indicate that the patient's condition is worsening? A. pH 7.48, PaCO2 30 mm Hg, PaO2 68 mm Hg B. pH 7.46, PaCO2 32 mm Hg, PaO2 61 mm Hg Cc pH 7.40, PaCO? 40 mm Hg, PaO2 62 mm Hg D. pH 7.39, PaCO2 30 mm Hg, PaQ2 60 mm Hg ANSWERV ¥ C. pH 7.40, PaCO2 40 mm Hg, PaO2 62 mm Hg The case study shows stage II asthma. Option c shows stage III asthma. The patient is still breathing at a fast rate, but carbon dioxide is starting to be retained as evidenced by the increase of the PaCO2 into normal range. Options a and b are still stage I. Option d shows a respiratory alkalosis with a metabolic acidosis because you would have expected the pH to be in an alkalotic range with the PaCO2 of 30. B. Hyperkalemia fon Hypercalcemia D. Hypomagnesemia ANSWERV V Hyperkalemia Banked blood is high in potassium because of hemolysis. Look for tall, peaked T waves and widening of the QRS complex. Other considerations with massive transfusion of banked blood are hypocalcemia, hypothermia, and decreased tissue oxygen delivery caused by decreased levels of 2,3-diphosphoglycerate. A 65-year-old woman reports severe dyspnea 2 days after abdominal surgery. She is transferred to the critical care unit. On 5 L of oxygen by nasal cannula, her arterial blood gases are as follows: pH 7.39 PaCQ2 35 mm Hg HCO3 19 mEq/L PaO2 40 mm Hg Arterial oxygen saturation 75% Why does this patient have hypoxemia without hypercapnia? Because carbon dioxide is more diffusible than oxygen B. Because carbon dioxide has more driving pressure Ci Because carbon dioxide is less diffusible than oxygen D. Because carbon dioxide exeretion by the kidney is increased ANSWERV V Because carbon dioxide is more diffusible than oxygen Carbon dioxide is 20 times more diffusible than oxygen. In conditions that affect diffusion but do not affect ventilation, expect the PaO2 to be decreased and the PaCO2 to be normal (or decreased in hyperventilation, as in this patient). If ventilation were affected, such as if this patient were fatiguing, the PaCO2 then would increase. Driving pressure is the fraction of the gas in inspired air multiplied by the barometric pressure. Because carbon dioxide is ~0.5% of inspired air, the driving pressure would be very low. The kidney eliminates bicarbonate and hydrogen ions, but the lungs eliminate carbon dioxide. A 55-year-old patient has headache, nuchal rigidity. photophobia, and positive Kernig's and Brudzinski's signs. These are consistent with which of the following? A Intracranial hemorrhage B. Subarachnoid hemorrhage $3 and S4 are low pitched, so choose options with the bell being used. S3 and S4 are heard at the mitral area (i.e., apex) unless the right ventricular is affected, and then they are heard in the tricuspid area. Low-Pitched is best heard with Bell The charge nurse on the 7 pm to 7 am shift was asked to assist a group of nurses to resolve their conflict so that their two opposing goals are discarded and new goals are adopted. This is an example of which of the following? A. Smoothing of conflict B. Facilitating collaboration Cc. Encouraging compromise D. Democratic approach ANSWERV ¥ Facilitating collaboration This is an cxample of facilitating collaboration. The nurse is, in essence, acting as mediator to assist these two groups in developing common goals. In smoothing, you would try to reduce the emotional stress of the conflict, but the conflict really would not get resolved. In compromising, each group would give up something that it wants. In a democratic approach, majority rules. Which of the following are the most clinically significant intracranial pressure (ICP) waveforms that require immediate intervention? A. A waves B. B waves Cc; C waves D. D waves ANSWERV Vv A waves, or plateau waves, are spontaneous, rapid increases in pressure between 50 and 200 mm Hg that last 5 minutes or more. A waves cause cerebral ischemia and are the most clinically significant ICP waveforms. Immediate intervention is necessary to prevent further brain injury and herniation. A waves are Awful Which of the following diagnostic tests would provide definitive evidence of a pneumothorax? A. Arterial blood gases Body temperature, body pH, PaCO2 levels, and 2,3-DPG levels affect the oxyhemoglobin dissociation curve. Cardiac output does not directly affect the curve. Which of the following is the primary difference between a tracheostomy tube and a laryngectomy tube? A. The laryngectomy tube is longer. B. The laryngectomy tube does not have a cuff. con Only the tracheostomy tube has an inner cannula. D. The tracheostomy tube has a larger lumen. ANSWERV V The laryngectomy tube does not have a cuff. A cuff is not necessary because food and fluid from the mouth can go only to the esophagus and the stomach, and air going into the laryngectomy tube can go only into the lungs. The only way this patient can aspirate is if fistula develops because the anatomy has been surgically altered by removal of the larynx. The mean QRS axis of ventricular tachycardia is most likely to be: normal or left axis deviation. B. right axis deviation or indeterminate axis. right axis deviation or left axis deviation. D. left axis deviation or indeterminate axis. ANSWERY ¥ left axis deviation or indeterminate axis. Ventricular tachycardia is most likely to be left axis deviation of —30 or greater or indeterminate axis, whereas aberrancy is more likely to be normal axis or right axis deviation. A 58-year-old man is admitted to the critical care unit with upper gastrointestinal bleeding. He has a history of chronic renal failure. When one is administering antacids, il is important to remember to avoid: A. magnesium-containing antacids. B. phosphate-binding antacids. iC. calcium-containing antacids. A 30-year-old man is in the surgical intensive care unit after exploratory laparotomy performed after he sustained a gunshot wound to the abdomen. He now has developed a pancreatic fistula. Which acid-base imbalance is this patient at risk for developing? A. Respiratory acidosis B. Metabolic acidosis Cc. Respiratory alkalosis D. Metabolic alkalosis ANSWERV V Metabolic acidosis The stomach is acidic, but the gastrointestinal tract below the stomach is alkaline. Pancreatic secretions are rich in bicarbonate, and these losses would cause metabolic acidosis. A 65-year-old man was admitted 2 hours ago after coronary artery bypass grafting. He has had the following vital sign changes: Admission 2 Hours Later Blood pressure (mm Hg) 110/80 96/76 Heart rate (per minute) 85 100 Right atrial pressure (RAP; mm Hg) 6 2 Pulmonary artery pressure (PAP; mm Hg) 24/12 18/6 Pulmonary artery occlusive pressure (PAOP; mm Ig) 105 Cardiac output (L/min) 6 4 Cardiac index (L/min/m2) 3.5 2.5 Systemic vascular resistance index (SVRI: dynes/sec/em—5) 1920 2590 What is the most likely cause of these changes? A. Stunned myocardium B. Blood loss fon Cardiac tamponade Dz. Intraoperative myocardial infarction ANSWERV ¥ Blood loss Note that all of the volume indicators (RAP, PAP, PAOP) have decreased. The increase in SVRI is compensatory and is caused by sympathetic nervous system stimulation. Stunned myocardium and intraoperative myocardial infarction more likely would cause an increase in PAOP because of heart failure. Cardiac tamponade would cause an increase in RAP, PAP, and PAOP. Provision of adequate nutrition in a malnourished patient may cause severe deficiency of which of the following electrolytes? Cc. Uncontrolled hypertension D. Pain lasting more than 6 hours ANSWER¥V ¥V Uncontrolled hypertension Pain of more than 6 hours duration is no longer a contraindication to the use of fibrinolytic drugs, although we certainly want to give fibrinolytic drugs as early as possible. Consider that pain indicates the presence of lactic acid and anaerobic metabolism. If the myocardial infarction is completed, there is no pain because dead myocardium does not metabolize aerobically or anaerobically. As long as there is pain, there is salvageable myocardium. Hypotension and heart block are not contraindications to fibrinolytic drugs, and they may improve with reperfusion of the myocardium. Uncontrolled hypertension increases the risk of hemorrhagic stroke. A 72-year-old woman arrives at the emergency department after becoming unresponsive while watching television with her husband. The nurse observes paralysis of her right extremities. aphasia, and lethargy. The patient receives fibrinolytic therapy. After the patient is stabilized, a diet is offered. The nurse knows that before the patient eats, it is crucial to check which of the following cranial nerves? IX,X I, VI D. VI, XI ANSWERVV IX, X Cranial nerves IX and X control the gag and swallow response. These must be intact bilaterally to protect the patient's airway. glossopharngeal and vagus A 23-year-old man is admitted via the emergency department after a motorcycle collision. Tlis Glasgow Coma Scale score was 12 in the emergency department, and it is still 12 upon his admission to the neurologic intensive care unit. Both eyes are ecchymotic and swollen shut, and he has multiple abrasions on his facc. Which of the following is the most likely diagnosis? A. Linear skull fracture B. Basal skull fracture Cc. Orbital fracture D. Mandibular fracture ANSWERV ¥ Basal skull fracture B. Evaluator fon Facilitator D. Advocate ANSWERV V Advocate A patient develops carpopedal spasm and neuromuscular irritability manifested by Chvostek's and Trousseau's signs. Which electrolyte imbalance should you suspect? A. Hyperkalemia B. Hypercalcemia Cc. Ilypermagnesemia D. Hyperphosphatemia ANS WER¥V ¥ Hyperphosphatemia The patient's signs/symptoms are associated with hypocalcemia and its reciprocal condition, hyperphosphatemia. The same signs/symptoms also are seen in hypomagnesemia. A patient with which of these conditions would have a normal serum lactate? A. Ventricular fibrillation B. Cardiogenic shock [es Severe anemia D. Renal failure ANSWERY ¥ Renal failure All of these will cause metabolic acidosis, but in renal failure the acidosis is related to accumulation of nonvolatile acids (e.g., urea and uric acid). Ventricular fibrillation, cardiogenic shock, and severe anemia would decrease tissue oxygen delivery, resulting in the conversion of metabolism from aerobic to anaerobic and the buildup of lactic acid. Lactic acidosis is reflected as an increase in serum lactate level. A patient has a diagnosis of pulmonary embolism made by pulmonary arteriography. He now is receiving 100% oxygen via a non-rebreathing mask for 24 hours. The nurse is concerned about the possibility of oxygen toxicity. What is a common, early sign of oxygen toxicity? A. Cyanosis 
