ICU Flashcards by Neil Neumann

Interventions which have been shown to reduce the duration of mechanical ventilation in patients with respiratory failure include which one of the following

Routine daily discontinuation of sedative infusions

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Successful use of non-invasive ventilation to prevent intubation will be most likely in a patient with which of the following

COPD with severe hypercarbia

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As ICU director, you are asked to help design a protocol to reduce the excessive rate of catheter-related bloodstream infections. Which of the following is supported by randomized trials showing reduction in the rate of these infections

Sterile gown, cap, mask, gloves, and full drapes during insertion

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All of the following findings are commonly present in a patient with cardiogenic shock from acute myocardial infarction EXCEPT

Bradycardia

Shock from any cause reduces coronary perfusion pressure, and associated pulmonary edema causes hypoxemia. Other physiologic compensatory responses to acute, severe pump failure include renal fluid retention and vasoconstriction. Although complete heart block might complicate a massive MI, the typical response to low output cardiogenic shock is tachycardia.

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Which of the following findings would be more typical of intrinsic renal injury than of pre-renal azotemia:

Fractional excretion of urea > 35%

Pre-renal azotemia from low cardiac output or hypovolemia causes the kidney to intensely retain sodium and water. Urine becomes hyperosmolar, with low fractional excretion of sodium and urea. BUN rises excessively compared to the increase in creatinine. A high fractional excretion of urea is more typical of intrinsic renal injury. The FEUrea remains diagnostic even in patients receiving furosemide which can elevate sodium excretion

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Which of the following interventions has been demonstrated to prevent or reduce the severity of acute kidney injury in ICU patients:

None of the above

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You are caring for an oliguric patient with sepsis from peritonitis. Their mean arterial pressure is 70 mmHg on 3.0 mcg/kg/min of norepinephrine. BUN is 86. pH is 7.15 with serum HCO3 of 12. Sodium is 129 and K is 6.6. The most appropriate mode of renal replacement therapy in this patient is which one of the following:

CVVHD – Continuous venovenous hemodialysis

This patient has several indications for acute dialysis, including hyperkalemia and severe acidosis. Low BP requiring vasopressors is a contraindication to intermittent hemodialysis because it would further lower BP. Peritoneal dialysis has been used in patients in shock but would be contraindicated in peritonitis. Among the continuous renal replacement therapies, hemodialysis would better correct blood chemistry than would hemofiltration

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Proper tracheal placement of an endotracheal tube is most definitively supported by which of the following findings

End-tidal exhaled CO2 of 6%

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In a patient with an unchanging minute ventilation, a decreased PaCO2 could be caused by which one of the following

Decreased pulmonary dead space

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Which of the following is characteristic of the arterial blood gases in severe carbon monoxide poisoning

Normal PaO2

Carbon monoxide binds avidly to hemoglobin and reduces the available sites for oxygen to bind. This reduces the arterial oxygen content, but not the PaO2. The %saturation is calculated from the PaO2. Because arterial content is reduced, after extraction by the tissues, mixed venous oxygen content is reduced as well. Hypercarbia is not seen with carbon monoxide poisoning; lactic acidosis, if present, would stimulate ventilation

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The following arterial blood gas is drawn on a mechanically ventilated patient breathing 30% oxygen: pH = 7.44, PaCO2 = 30, PaO2 = 274 mmHg. This is most suggestive of

Laboratory error

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A patient being mechanically ventilated on 90% oxygen, 12 cmH2O PEEP and volume Assist/Control ventilation has the following ABGs : pH = 7.43, PaCO2 = 20, PaO2 = 55, HCO3 = 15. This ABG indicates which of the following abnormalities:

Combined metabolic acidosis and respiratory alkalosis

The pH is on the alkalotic side of normal. If this were a simple acute respiratory alkalosis, the pH would be higher. It increases about 0.08 units/10 mmHg fall in PCO2. Compensation for a metabolic acidosis would not increase pH to >7.40; it would remain in the low-normal or sub-normal range. Combined metabolic alkalosis and respiratory acidosis could result in this pH, but the PCO2 has changed in the wrong direction. V/Q mismatch would not account for the pH and PCO2 abnormalities, and PaO2 should be much higher on 90% oxygen.

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Assuming they lack contraindications to the medications, all of the following are recommended in the initial treatment of a patient presenting with non-ST segment elevation MI and ongoing chest pain EXCEPT:

ACE-inhibitor

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Which of the following therapies would be most useful useful to improve cardiac output in the ICU management of acute decompensated heart failure:

Dobutamine

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Which of the following illnesses would most typically cause hypercarbic respiratory failure

Myasthenia Gravis

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A patient with a large pulmonary embolism has a blood pressure of 95/70 mmHg, heart rate of 123, and a blood gas on room air of pH 7.30, PaCO2 = 30 mmHg, PaO2 = 40 mmHg. Which of the following therapies should be given first:

Supplemental oxygen

Propranolol would be contraindicated in this situation, as it might precipitate shock in this patient with compensatory tachycardia. NIV would not help since the patient is ventilating just fine. A fluid bolus might help with the tachycardia, but this patient’s blood pressure is not critically low. Heparin and oxygen are both indicated, but oxygen to relieve the severe hypoxemia is the more urgent.

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A paralyzed patient is receiving volume assist/control mechanical ventilation. If they develop a fever, which one of the following changes will occur?

PaCO2 will rise

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Which of the following disorders is most likely to respond to non-invasive ventilation without requiring intubation?

Asthma exacerbation

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A sedated patient is receiving assist/control ventilation through a #6 endotracheal tube placed emergently. To allow bronchoscopy, the tube is exchanged for a larger, #8 tube. Which of the following changes in respiratory mechanics would this cause?

Decreased peak airway pressure

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An anxious patient is receiving assist/control ventilation at a set rate of 24. Their measured respiratory rate is 28. An arterial blood gas shows a pH of 7.55, PaCO2 22, PaO2 133. What effect will decreasing the set rate to 12 have on their arterial blood gases?

No effect

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A heavily sedated child on pressure/control ventilation is receiving a tidal volume of 150 ml with a set pressure of 20 cmH20 and PEEP set at 0 cmH2O. They develop bronchospasm and autoPEEP (intrinsic PEEP) increases from zero to 10 cmH2O. If no changes are made to the ventilator, which one of the following changes to their ventilation will occur?

Minute ventilation (Ve) will fall

Pressure-control ventilation limits the airway pressure to the value you have set above the set PEEP. The development of autoPEEP during bronchospasm indicates the lungs do not have enough time to empty fully during expiration. However, because the maximum airway pressure is fixed by the ventilator, end-inspiratory lung volume will not increase. Tidal volume becomes squeezed between the fixed end-inspiratory value and the rising end-expiratory value. Minute ventilation will fall and PaCO2 will rise. Airway resistance will have increased because of the bronchospasm but will not be altered by the ventilatory pattern.

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In which of the following modes of ventilation will the patient do the MOST work of breathing?

Continuous positive airway pressure

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A patient receiving pressure support ventilation develops peritonitis with a tense abdomen and will need emergency surgery. While awaiting the OR, the best change to make to the ventilator is which one of the following:

Change mode to volume assist control ventilation

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You place a pulmonary artery catheter to assist in the differential diagnosis and management of a patient with a blood pressure of 80/60. Match the following patient description with the appropriate hemodynamic profile in the table below:

A 17 year old girl who is intubated for surgical resection of a Meckel’s diverticulum. She is placed on high levels of PEEP in an attempt to prevent atelectasis.

High levels of PEEP increase pleural pressure and lung volume, especially in a patient such as this with normal lungs. This will increase pulmonary vascular resistance and elevate all of the intrathoracic vascular pressures. The increased right atrial pressure will decrease venous return. This is the profile shown in D

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A An acute massive pulmonary embolism will increase pulmonary vascular resistance. Pulmonary artery pressure will rise, but mean Ppa will not usually exceed about 40 mmHg because the right ventricle is thin-walled and incapable of generating more pressure. Cardiac output will fall. Left-sided pressures such as the wedge pressure remain relatively normal, but can increase somewhat from the mechanism of ventricular interdependence as the RV dilates. This is described by the set of parameters shown in row A.

In which of the following situations should an anti-pseudomonal agent be included in empiric coverage for a septic patient

55 year old woman with suspected ventilator-associated pneumonia, one week into therapy for ARDS

You begin empiric vancomycin and piperacillin/tazobactam on an intubated Medical patient with a central venous line and fever who has been in the MICU for 5 days. The central line will be removed, and prior to antibiotic administration you sent cultures of urine, blood, and sputum. The earliest that it is correct to discontinue vancomycin is when which one of the following conditions have been met:

72 hours later, when all diagnostic studies and cultures are negative but the fever persists Antibiotic "stewardship" describes the responsible use of antibiotics to minimize acquisition of resistance. Vancomycin must often be started empirically to cover for MRSA. However, staph grows rapidly and readily and vancomycin can be discontinued after 48 hours if cultures are negative. Positive blood cultures with an alternative organism is strongly suggestive that vancomycin is unnecessary, but co-infection is possible. Continued fever suggests that the antibiotics are ineffective, the fever is not from infection or an abscess has not been drained

Which one of the following antibiotics require dose adjustment for a patient with renal insufficiency and a serum Cr = 2.5 mg%:

vancomycin

In a patient with a definite, severe allergy to penicillin, which antibiotic is least likely to cause an allergic reaction

aztreonam Although structurally a beta-lactam, aztreonam has the least cross-reactivity to penicillin and can be safely administered to patients with penicillin allergy

Meropenem has activity against all of the following organisms EXCEPT

MRSA

A patient with HIV/AIDS is being treated with Bactrim for PCP pneumonia, is mechanically ventilated on 80% oxygen and 12 cmH2O PEEP, and is being sedated with infusions of fentanyl, lorazepam, and propofol. Mean arterial pressure has been maintained 65-70 mmHg on norepinephrine infusion. They are receiving routine prophylactic therapy for DVT (unfractionated heparin, sc, and oral pantoprazole). They have been slowly improving, until day 7, when their blood gases show a new acidosis (pH 7.25, PaCO2 32, PaO2 69). The nurse noted a heart rate of 45 and sent cardiac enzymes. Creatine kinase is 554 with 1% MB fraction. The medication that should be immediately discontinued because it is the most likely cause of these new findings is:

Propofol

Which of the following statements is correct in regards to the association between ICU delirium and mortality

Delirium during an ICU stay increases the risk of both hospital and 6-month mortality.

In which of the following forms of shock is an INCREASED cardiac output most likely

Distributive

Cardiogenic and hypovolemic shock can be distinguished from each other with knowledge of which of the following patient features

Central venous pressure

What is the approximate mortality rate from cardiogenic shock after acute myocardial infarction for which reperfusion is unsuccessful?

\>50%

You are called to see an elderly male patient when their nurse notes they are confused. When you arrive, you find he is oriented to place only. Blood pressure is 90/40 mmHg, pulse is 120, RR is 35, temperature is 38.3oC. Skin is mottled and his extremities are cool. He has no jugular venous distension, but becomes combative when you attempt a more comprehensive examination. Review of his bedside chart reveals he has had 50 cc urine output over the last shift. Initial laboratory studies should include all of the following EXCEPT

echocardiogram This case scenario describes a patient who is in shock, with low blood pressure accompanied by signs of hypoperfusion and organ dysfunction. Initial studies should be directed toward establishing the most likely diagnoses and determining severity of illness and need for interventions. All of the listed studies would be useful (along with cultures of blood and urine, full CBC and metabolic profile and an ECG). However, an echocardiogram would not be immediately helpful unless you suspected tamponade. This patient's flat neck veins make that unlikely.

(Same case) You are called to see an elderly male patient when their nurse notes they are confused. When you arrive, you find he is oriented to place only. Blood pressure is 90/40 mmHg, pulse is 120, RR is 35, temperature is 38.3oC. Skin is mottled and his extremities are cool. He has no jugular venous distension, but becomes combative when you attempt a more comprehensive examination. Review of his bedside chart reveals he has had 50 cc urine output over the last shift. While awaiting results of diagnostic studies, initial interventions should include all of the following EXCEPT:

Naloxone

Which of the following vasopressors will have the least direct effect on heart rate

Phenylephrine

A 54 year old male was admitted to the ICU with septic shock. Sepsis has resolved 6 days ago, but he has suffered acute renal failure from acute tubular necrosis. Nephrology has been consulted, but he has not started dialysis. Today, the NG tube returns bright red blood. Blood pressure is 100/50, pulse is 126, and respiratory rate is 32. Upper endoscopy is scheduled to occur in the next few hours. Results of laboratory testing includes the following (see below). Hemoglobin 7.3 WBCs 13,500 Platelets 160,000 INR 1.2 aPTT 24 seconds Na 132 K 5.2 HCO3 20 Cl 98 Glucose 192 P 4.5 Mg 2.3 BUN 114 Cr 3.9 In addition to transfusion of RBCs and pantoprazole infusion, which other therapy will help with this patient’s bleeding:

Dialysis Acidosis Electrolyte abnormalities Intoxications Overload of fluids Uremia

Disseminated Intravascular Coagulation is specifically diagnosed by the presence of which of the following single laboratory abnormalities:

None of the above No single blood test reliably diagnoses DIC, which is diagnosed based on a combination of several of the tests listed in the appropriate clinical setting

Treatment of immune-mediated heparin induced thrombocytopenia in a patient with a recent pulmonary embolism includes immediately stopping unfractionated heparin and doing which of the following:

Begin argatroban

A 72 year old patient with chronic atrial fibrillation was stable 8 days following cardiac surgery. Medications include S.C. heparin, ranitidine, amiodarone, and Coumadin. He then developed fever and was begun on Vancomycin and piperacillin/tazobactam. Forty-eight hours later, fever has resolved. On routine morning blood work, platelet count is noted to have decreased to 120,000, from 340,000 two days ago. The most likely cause of this decrease is which of the following

Heparin

When combined with a low pre-test probability, which of the following tests, when normal, can be used to rule out a pulmonary embolism:

d-dimer by ELISA

Metabolic responses to physiologic stress such as sepsis include which of the following

catabolism

In patients with which of the following conditions will the calculation of nitrogen balance base on urine urea nitrogen loss to assess nutrition support be most valid?

Severe sepsis

A 65 year-old male remains intubated and mechanically ventilated 4 days after a partial small bowel resection for Crohns Disease. Weaning has been difficult. He is 5’8” (173 cm) tall and weighs 132 lbs (60 kg). He is febrile to 38.4, with heart rate of 114, BP 144/60, RR of 28 on assist-control ventilation. Arterial blood gases on 30% oxygen and 5 PEEP are pH 7.34, PaCO2 44, PaO2 125. Because of concern of a possible anastomotic leak and persistent ileus, he is receiving total parenteral nutrition. This includes 85 grams of protein and 2800 kcal/day. To confirm that this is meeting his needs, indirect calorimetry with a metabolic cart is performed and his respiratory quotient is measured at 1.3. This suggests which of the following:

Ventilator dependency may be partially due to caloric overfeeding

A 60 year old man with known cirrhosis from hepatitis B and alcohol use is admitted to the ICU with spontaneous bacterial peritonitis. He undergoes a large volume paracentesis, removing 5 liters of ascites with 550 WBCs/mm3. Despite receiving IV albumin during the procedure, mean arterial pressure falls to 50 mmHg. The patient is resuscitated with saline and treated with antibiotics. By the 4th ICU day, he appears stable, but bilirubin has risen from 14 to 23, creatinine has risen from 1.3 to 3.7, and he is oliguric. The finding that would most strongly support the diagnosis of hepatorenal syndrome as the cause of the acute renal failure is which one of the following:

Urine Na 8 mmol/l

Cardiovascular effects of aging include which one of the following:

Increased stiffness of the left ventricle

Which of the following is the most common iatrogenic complication of elderly ICU patients

Adverse drug reaction The elderly are more prone to all complications of hospitalization, but the most common ICU complication in all age groups is an adverse drug reaction.

Tight control of blood glucose, targeting levels of 80-110 mg%, have been shown to decrease hospital mortality in which of the following patient types?

Cardiothoracic surgical patients receiving IV glucose infusion or TPN Tight glucose control was shown to decrease mortality in only a single study, although that study had an out-sized influence. The study was performed in a surgical ICU with mostly cardiac surgical patients, and all patients were given TPN or IV glucose as part of that ICU routine. Attempts to duplicate that study without a carbohydrate load or in other ICU types have failed to find a benefit of such tight control, and found that it causes unacceptable rates of hypoglycemia. Current recommendations suggest more liberal targets of \<180 mg%.

A 60 year old man with lung cancer metastatic to liver and bone is admitted to the hospital medicine service with community acquired pneumonia. Laboratory tests include a bilirubin of 5 mg/dL, creatinine of 1.8 mg/dL, albumin of 2.5 gm/dL and INR of 2.3. Despite antibiotics, his condition worsens, and he requires oxygen by 100% non-rebreather mask to maintain SpO2 \> 90%. He is agitated and confused. His oncologist described the patient as "terminal" in his admission note, but has never discussed advanced directives. You are consulted because the floor team believes he will die without intubation, and when they spoke with the family the wife said “he would have wanted everything.” You also speak to the family and explain the prognosis and likely hospital course. The wife reiterates that “he would have wanted everything.” The nurse calls you urgently to the bedside because the patient has only a thready pulse. What are you ethically and legally obliged to do?

Explain to the family why you will withhold resuscitation and intubation and provide comfort measures. This is a difficult situation that you may well face as a resident. Medical ethical principles require you to respect patient autonomy, but do not require you to provide futile care at the patient's request. Resuscitation of a patient dying of cancer is both futile and cruel; CPR will break bones, anoxic brain injury is likely, and virtually no patient who arrests due to cancer survives to hospital discharge. The patient's request that you "do everything" is too vague and potentially uniformed to guide you; everything has already been done for this patient, and it was ineffective. Maryland law protects you for withholding resuscitation under these circumstances, provided two licensed physicians agree the patient is in an "end stage condition" (note the purposeful ambiguity). Knowing what you should do in a circumstance like this does not mean you will do it when you find yourself there; particularly as a trainee you should err on the side of life. I have often extubated patients like this after a day or two when the dust and panic have settled.

You are caring for a mechanically ventilated patient with severe ischemic cardiomyopathy and hepatic cirrhosis who is slowly developing renal failure from poor cardiac output. The patient has no written advanced directives, and you plan to discuss dialysis with the family. In preparation, you are deliberating whether to offer dialysis at all, or to offer a trial of dialysis, to be withdrawn if there is no improvement in the patient’s condition and prognosis after a few weeks. Which of the following describes the ethical distinction between withholding dialysis and withdrawing dialysis?

There is no ethical distinction between withholding and withdrawing dialysis

A patient one year out from lung transplantation is intubated but recovering from acute respiratory failure from presumed pneumonia. No organism was isolated; they being treated empirically). For the last 3 days, a gradual increase in their liver function tests has been noted. Today's values are as follows: AST 40 IU/L (nl 10-35) ALT 45 IU/L (nl 10-52) Alk Phos 140 IU/L (nl 30-120) Which of the following should be done FIRST

Review +/- discontinuation of hepatotoxic medications

Which of the following is the most common source of infection among all cases of severe sepsis?

Respiratory tract

Hemodynamic derangements in warm septic shock include all of the following EXCEPT

Decreased venous return Warm septic shock refers to a state of unregulated vasodilation. It is usually manifest after a patient has been volume resuscitated. The shock is due to endothelial cell dysfunction which causes dilation of arterioles, the site of most of the peripheral vascular resistance. Local blood flow regulation is lost. Tachycardia is a compensatory response to the low blood pressure. Warm shock is a high-output state, and hence venous return is increased, not decreased.

In a septic patient, a mixed venous oxygen saturation of 58% suggests which of the following conditions?

Under-resuscitation

Sepsis guidelines recommend which of the following endpoints for the early treatment of septic shock?

Appropriate empiric antibiotics within 1 hour.

A patient with septic shock has been resuscitated with 6 liters of saline to a CVP of 8 mmHg, and requires vasopressin and high doses of norepinephrine to maintain mean arterial pressure at 63-66 mmHg. An arterial blood gas reveals pH 7.18, PaCO2 30 mmHg, and PaO2 135 mmHg on 40% oxygen. What hemodynamic effects would you expect from bolusing with one liter of isotonic sodium bicarbonate compared to one liter of isotonic sodium chloride?

No difference in hemodynamic effects

In a comatose patient, which of the following is the MOST urgent indication for a head CT scan?

Unilateral fixed pupil

A mechanism whereby midazolam has a short duration of action after short-term administration and a long duration of action after long-term administration is which of the following:

Accumulation from high lipid solubility

The most common outcome of drug metabolism is which of the following

Increased aqueous solubility of the metabolite

A 64 year old man with diabetes and renal insufficiency presents with aphasia and right hemiplegia that began suddenly 2 hours ago. Blood pressure is 175/110, pulse is 105, RR is 26 and he is afebrile. Exam is normal except for the neurologic findings as noted. Blood laboratory studies are normal except for a glucose of 210 and creatinine of 2.3. Emergency non-contrast CT scan is normal. ECG shows atrial fibrillation. Which of the following should be done next

Administer tPA

What is the expected pharmacokinetic effect when a drug metabolic enzyme reaches saturation?

Linear elimination kinetics become non-linear

The most important intervention in a patient 34 weeks pregnant with BP 170/100, 4+ proteinuria, creatinine of 1.4 mg/dL and dyspnea from mild pulmonary edema is which one of the following:

Delivery

# A 26 year-old man comes to the ED with complaints of 4 days of fever, rigors, productive cough, and dyspnea. His BP is 100/60 with a pulse of 130, respiratory rate of 44 and temperature of 39o. He appears acutely ill, and lung exam shows bronchial breath sounds in the right base. Cardiac and abdominal exam is normal, and neurologic exam is grossly intact. Lab work reveals a WBC count of 18,000 with 15% bands. Arterial blood gas on 60% oxygen is pH 7.32, PaCO2 30 mmHg, PaO2 62 mmHg. He is immediately treated with antibiotics and intravenous fluids via a central venous line. Because of severe dyspnea and hypoxia, he is intubated. Chest X-ray after intubation is shown here:

ARDS

Small tidal volumes during mechanical ventilation

Fatigue and weakness

An obese 70 year old man has returned to the SICU after a complicated exploratory laparotomy and partial small bowel resection for ischemic bowel. He received 6 liters of lactated Ringers pre-operatively and another 5 in the OR. He is hemodynamically stable, mechanically ventilated and sedated. You are called to evaluate him when the nurse notes his blood pressure has fallen to 70/palp and heart rate increased to 135. He has made 15 cc of urine over the past hour. He is afebrile. CVP is 15 cmH2O. Exam shows him to be comfortably sedated, with normal breath and heart sounds and a firm, silent, obese abdomen. You note that the ventilator is alarming and peak airway pressures have increased to 60 cmH2O. You order a blood gas, which shows a metabolic acidosis. A 1 liter normal saline bolus only transiently improves his blood pressure and does not increase his urine output. Which of the following interventions is most likely to reverse his condition:

Opening his surgical incision

All of the following treatments have been shown to improve oxygenation in the first few days of ARDS EXCEPT

Corticosteroids Corticosteroids may have a role to speed resolution of inflammation in the late, fibroproliferative phase in ARDS, beginning after one week. The other therapies have all been shown to improve oxygenation quickly and to be more effective in patients whose lungs are recruitable. This tends to be the case early in ARDS, before fibrosis sets in.

Which of the following has been shown to reduce the acute re-bleeding rate from peptic ulcer disease

72 hour infusion of a proton-pump inhibitor

In a patient in shock, which of the following signs would help identify a tension pneumothorax as the cause, rather than pericardial tamponade:

Increased peak and plateau airway pressures

A patient recovering from hip surgery sustains a massive pulmonary embolism. CXR shows no infiltrates. ABG on 100% O2 is pH 7.38, PaCO2 36, PaO2 112. What would best account for these findings:

Patent foramen ovale This patient has a large physiologic shunt (Aa gradient ~550 mmHg on 100% oxygen). This could be due to alveolar filling from pulmonary edema or hemorrhage, but these would be visible on CXR. Hypoventilation, by definition, would require PaCO2\>45 mmHg. Bronchospasm causes V/Q mismatch, not shunt. However, the acute increase in right atrial pressure following a massive PE can open a patent foramen ovale and cause profound hypoxemia from shunting.

Elements of the “ventilator bundle” of interventions recommended for all intubated, mechanically ventilated patients include all of the following EXCEPT

Holding tube feeding for gastric residuals \> 2 x hourly rate Even fairly large gastric residuals (up to 400 ml in some studies) have not been shown to increase rates of aspiration or pneumonia. Twice the hourly rate would be a residual \<120 ml in most patients. The other choices are recommended for all mechanically ventilated patients.

A 24 year old patient requires intubation in the Emergency Department due to a severe asthma attack that had begun 3 days earlier. She is sedated and paralyzed for intubation and placed on assist/control ventilation. Five minutes later you are called to the bedside because she is pulseless. Among the causes running through your mind, the LEAST likely explanation is which of the following:

Ventricular fibrillation In this setting, breath-stacking (dynamic hyperinflation and intrinsic PEEP) on mechanical ventilation is common. This can cause PEA, or result in tension pneumothorax which does. Patients who have been ill and dyspneic for several days are also typically relatively hypovolemic from poor PO intake, fever, and increased insensible respiratory losses. Even in the absence of dynamic hyperinflation, and certainly in its presence, hypovolemia and positive pressure ventilation can cause shock or PEA. Endotracheal tube malposition should always be considered in a freshly intubated patient who arrests. The only option which does not fit this scenario is ventricular fibrillation.....always possible, but not especially likely in this case.

A patient develops fulminant hepatic failure after a suicide attempt with acetaminophen, vodka, and Amanita phalloides (Death Cap) mushrooms. Over the next several days, the most ominous laboratory sign suggesting they will need liver transplantation is which one of the following

Rising INR

A patient with a history of CHF, hepatic cirrhosis and encephalopathy is admitted with a massive upper GI bleed and is intubated for airway protection. Emergency endoscopy reveals esophageal varices, but bleeding is too brisk to identify a source. Over the past 6 hours, they have been transfused 8 units of RBCs, 8 units of FFP, 2 units of platelets, and given calcium replacement, pantoprazole, and octreotide. Despite correction of INR, nasogastric tube continues to return bright red blood. The best intervention at this time is which of the following:

Sengstaken-Blakemore tube placement A Sengstaken-Blakemore tube will, at least temporarily, stop bleeding from esophageal varices. These are the most likely source of a bleed that is this brisk. H2 blocker infusion and vasopressin have no advantage over pantoprozole and octreotide. Correction of the INR indicates more FFP is not immediately needed. Cryoprecipitate may be helpful to replete fibrinogen, but hemostasis with a Blakemore tube should be attempted first. If it is ineffective, angiography for embolization of a bleeding ulcer should be attempted next.

Which one of the following is the best indication for thrombolytic therapy in acute pulmonary embolism?

Shock despite volume resuscitation

The best position seen on CXR for the tip of a central venous catheter placed via an upper extremity access site is which of the following:

SVC-RA junction

Immediate effects of hemorrhage of 30% of blood volume would include all of the following EXCEPT

Decreased hemaocrit

Which of the following statements is correct regarding the use of colloid versus crystalloid solutions for resuscitation from hypovolemic shock:

After equal volumes of colloid or crystalloid resuscitation fluid, colloid will cause a greater decrease in hematocrit.