2009.07.31 Quiz: Near-drowning

Which of the following is incorrect about near-drowning?
A. Sterile water was found to be the most disruptive of pulmonary function.
B. Freshwater acts partly by inactivating surfactant in the alveoli. 
C. Hypertonic seawater may draw additional fluid from the plasma into the alveoli, thereby causing pulmonary edema despite a decreased intravascular volume.
D. Hypertonic seawater does not damage type II pneumocytes.

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2009.07.26 Sun Quiz: Communication with families of critically ill patients

In "Azoulay E, Chevret S, Leleu G, et al. Half the families of intensive care unit patients experience inadequate communication with physicians. Crit Care Med 2000;28:3044–3049", it was found that less than half of the families knew what was wrong with their loved one or their prognosis 48 hours after admission to the ICU. About communication with families of critically ill patients, which of the following is not advised?
A. Meet with families on a regular basis
B. Decrease amount of conflicting information by having the same individuals meet with the family and/or decrease the number of providers who meet with the family
C. Attend to the psychological fact that stress, emotions and fatigue will decrease their understanding, so be more empathetic and develop written or computerized information.
D. For end-of-life communication, use direct and frank language, for example, when treatment is considered futile, tell them that "There Is nothing more to do". Clarify with them by saying "Would you like us to do everything possible?" to let them feel that we are respecting their wish, and to avoid ambiguity and future litigation, we should say "We will stop the breathing machine and the antibiotics and if his heart stops we won't try to resuscitate", or concise language like "we will withdraw our care". 

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2009.07.29 Quiz: Fat Embolism

Which of the following is incorrect about fat embolism?
A. Fat emboli occur after long bone fractures and large joint replacement. The classic fat embolism syndrome consists of progressive respiratory insufficiency, petechial rash, and altered mental status, and is estimated to occur in 0.5% to 2.0% of patients with long bone fractures.
B. The onset is usually immediate after injury.  
C. The petechiae may appear about the head, neck, or axillae; in the conjunctivae; and in mucous membranes. The patient has hypoxemia, a widened P(A-a)O 2, and diffuse bilateral infiltrates on chest radiography.
D. Although corticosteroids have been used, there are no controlled studies to support their use. 

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2009.07.28 Quiz: TCA Poisoning

Which of the following is incorrect about tricyclic antidepressants overdose?
A. GI decontamination for severely ill patients should consist of gastric lavage followed by the administration of activated charcoal, and, preferably, the patient has to pass a charcoal stool. Because some cyclic antidepressants have a small enterohepatic circulation, an additional one to two doses of aqueous charcoal (25 g) can be considered every 4 hours until the patient awakens
B. Hemodialysis and hemoperfusion are not effective in reducing the toxic effects of cyclic antidepressants
C. Alkalinization for abnormal cardiac conduction (QRS complex greater than 100 milliseconds in the limb leads, and ventricular dysrhythmias) also helps to control seizure activity.
D. Diuresis of an alkaline urine is not necessary for the beneficial effect of alkalinization for abnormal cardiac conduction.

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2009.07.27 Quiz: Prasugrel

Which of the following about Prasugrel is incorrect?
A. It is a new antiplatelet agent just approved on July 10, 2009 by the Food and Drug Administration (FDA) for use in patients with unstable angina or myocardial infarction who undergo percutaneous coronary intervention (PCI).
B. The mechanism is inhibition of  the platelet adenosine diphosphate (ADP) receptor.
C. Prasugrel is more effective than ticlopidine and clopidogrel at inhibiting the ADP receptor largely because it is more efficiently metabolized, so more active metabolite is delivered to the platelet.
D. In the TRITON–TIMI 38 trial, prasugrel showed a reduction in the risk of myocardial infarction and stent thrombosis, and there was also less major bleeding events.

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2009.07.25 Quiz: Pathophysiology of generalized reactions

Which of the following in incorrect about the pathophysiology of generalized reactions?
A. Immunoglobulin E-mediated processes: because immunologic sensitization must occur, reactions do not occur with first exposures.
B. Complement system activation: reactions to blood and blood products are presumed to be associated with immune complex formation and subsequent complement activation.
C. Direct mast cell degranulation. commonly related to food and antiotics.
D. Abnormalities of arachidonic acid metabolism: systemic reactions to aspirin and nonsteroidal antiinflammatory drugs (NSAIDs).The reactions usually occur within 180 minutes of ingestion and are often associated with profuse rhinorrhea and flushing.

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2009.07.24 Quiz: Clostridium difficile colitis

Which of the following is incorrect about the diagnosis of Clostrium difficile-related pseudomembranous colitis?
A. The most popular diagnostic test is a tissue culture assay for a cytotoxin that is elaborated by C. difficile.
B. Because nontoxigenic strains of C. difficile can be isolated in the stool of asymptomatic patients, tests that document the presence of C. difficile in stool (i.e., stool culture or latex agglutination test) lack specificity.
C. The cytotoxin assay has high sensitivity, performing serial stool cytotoxin assays is not necessary
D. Direct visualization with proctosigmoidoscopy or colonoscopy of the lower GI mucosa is a valuable but underused diagnostic test for C. difficile colitis.
 

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2009.07.23 Quiz: Magnesium

About magnesium, which of the following is incorrect?
A. Plasma contains only 0.3% of total body magnesium, almost 90% is in bone, muscle and soft tissue. In patients with magnesium deficiency, serum magnesium levels can be normal in face of total body magnesium depletion.
B. Only 55% of the magnesium in plasma is in the ionized (active) form. When the serum magnesium is abnormally low, it is impossible to determine whether the problem is a decrease in the ionized (active) fraction or a decrease in the bound fractions (e.g., hypoproteinemia).
C. The hypocalcemia that accompanies magnesium depletion is due to impaired parathormone release combined with an impaired end-organ response to parathormone. Magnesium deficiency may also act on bone directly to reduce calcium release.
D. If hypophosphatemia is ever found, it is unlikely to be related to magnesium metabolism.

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2009.07.22 Quiz: Sick Euthyroid Syndrome (or Nonthyroidal Illness Syndrome)

Regarding sick euthyroid syndrome (or nonthyroidal illness syndrome) in critically ill patients, which of the following is incorrect?
A. Common to all of the abnormalities in thyroid hormone concentrations seen in critically ill patients is a substantial depression of serum total T 3 levels, which can occur as early as 24 hours after the onset of illness.
B. Serum total T 4 levels may be elevated early in acute illness, as the severity and the duration of the illness increases, serum total T 4 levels decrease into the subnormal range. Decrease in serum TSH levels is also seen.
C. Despite marked decreases in serum total T 4 and T 3 levels in the critically ill patient, the free hormone levels have been reported to be normal or even elevated.
D. Full restoration of thyroid hormone levels to the normal range usually occurs the latest within days of recovery of the illness.

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2009.07.21 Quiz: Poor Prognostic Factors After Hypoxic Brain Injury

Which of the following is not a poor prognostic indicator after hypoxic brain injury?
A. Absence of pupillary or motor response to pain by the third day.
B. The loss of vestibuloocular responses at 12 hours and the presence of decerebrate or decorticate posturing at 24 hours.
C. Electroencephalogram (EEG) patterns: nonreactive EEG; burst suppression; alpha coma.
D. Absent cortical N20 on somatosensory evoked response at 72 hours, or unobtainable short-latency somatosensory evoked cortical potentials 8 hours after cardiorespiratory arrest.
E. Hypothermia at the time of the anoxic event.
F. The presence of either diffuse edema or watershed infarctions on CT scans.
G. Loss of gray-white matter distinction on CT scan and severe abnormalities on diffusion-weighted imaging.

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2009.07.20 Quiz: Common Invasive Molds in Hematologic Cancers

About the clinical and mycologic characteristics of the most common invasive molds in hematologic cancers, which of the following is incorrect?
A. Aspergillus species: blood cultures often not positive, non-culture based methods (tests for galactomannan and 1.3-beta-D-glucan) may facilitate diagnosis
B. Fusarium species: skin lesions characteristically erythematous and nodular, may have a necrotic center
C. Zygomycetes: preferred therapy is high dose liposomal amphotericin B or posaconazole
D. Scedosporium species: associated with near-drowning, resistant to amphotericin B
E. Phaeohyphomycosis: resistant to all anti-fungals

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2009.07.19 Sun Quiz: Negligence

Which of the following is correct about negligence?
A. The three requirements for a successful claim in negligence are: the defendant owed the claimant a duty of care, the defendant broke that duty of care, the defendant's breach of duty caused the damage to the claimant
B. A hospital can rely on a lack of resources as a defence to a claim for negligence
C. Regarding the duty of care, there is a general duty on doctors to provide treatment for people, e.g. a doctor who is watching a film at the cinema has to help someone who faints.
D. A patient is obese and a doctor injects into the arm tissue instead of a vein because of difficulty in finding the vein, and causes an abscess. The doctor is negligent.

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2009.07.18 Quiz: Swine Influenza Transmission To Humans

Which of the following is incorrect?
A. The first recognized case of human disease from a swine influenza triple reassortant influenza A (H1N1) virus occurred in a 17-year-old who had been exposed to pigs at a slaughterhouse in Wisconsin.
B. In April 2009, in the first two cases of S-OIV were identified in the United States, genetic analysis of the strains showed that they were derived from a new reassortment of six gene segments from the known triple reassortant swine virus, and two gene segments (NA and matrix protein) from the Eurasian influenza A (H1N1) swine virus lineage.
C. The 2009 lineage carries three gene segments that share a common (albeit remote) descent from the 1918 virus with the human seasonal virus.
D. It has been found that cytotoxic T lymphocytes that are generated by seasonal influenza viruses against conserved epitopes could not provide heterotypic immune responses that could dampen transmission of the novel H1N1 virus.

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2009.07.17 Quiz: Prospective Cohort, Retrospective Cohort, Case-Control, Nested Case-Control Studies: Which is Which?

To design a study to assess if smoking and lung cancer is related, which of the following is incorrect?
A. Prospective cohort study = To follow a group of smokers and non-smokers and compare them in future for the onset of lung cancer.
B. Retrospective cohort study = To search the the medical records of 20 years ago of smokers and non-smokers and compare their subsequent onset of lung cancer (also called historical control study).
C. Case-control study = To compare a group of lung cancer individuals (case) with a group of non-lung cancer individuals (controls) and assess which group has more smokers (also called retrospective study)
D. Nested case-control study = case-control study with matching done using statistical methods

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2009.07.16 Quiz: Streptococcus pneumoniae

Which of the following is true regarding Penicillin-resistant Streptococcus pneumoniae (PRSP)?
A. The major mechansim is beta-lactamase production.
B. The prevalence in Hong Kong is quoted to be 20% of all strains.
C. When quinolones are to be used for treatment, ciprofloxacin and ofloxacin are the best choices.
D. The current breakpoints that define penicillin activity versus Streptococcus pneumoniae, that is, =/< 0.06 µg/mL (S), 0.12-1 (I), and ≥ 2 (R) are relevant to patients with meningitis as related to the clinical outcome, but they are not predictive of outcome in patients with bronchopulmonary infections in that they over-predict failure.

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2009.07.14 Quiz: Universal and Standard Precautions

Prepared by Dr Lily CHANG, Intensive Care Unit, PYNEH, Hong Hong
Which of the following is incorrect regarding Universal Precautions and Standard Precautions?
A. Universal Precautions refers to blood and certain body fluids of all patients are considered potentially infectious for HIV, HBV and other bloodborne pathogens. Standard Precautions goes beyond Universal Precautions, apply to blood and other body fluids, secretions and excretions, nonintact skin and mucous membranes.
B. Universal Precautions apply to bodily fluids include semen, vaginal secretions, synovial fluid, amniotic fluid, CSF, pleural fluid, peritoneal fluid and pericardial fluid.
C. Standard Precautions apply to all excretions including sweat.
D. Universal Precautions do not apply to faeces, urine, vomitus, sputum, nasal secretions and saliva unless there is visible blood.

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2009.07.15 Quiz: Antiplatelet Agents

Which of the following blocks the ADP receptor on the antiplatelet membrane?
A. Eptifibatide
B. Dipyridamole
C. Clopidogrel
D. Abciximab

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2009.07.13 Quiz: Management of occlusion and thrombosis associated with long-term indwelling central venous catheters

For obstruction of long-term indwelling central venous catheters by fibrin sheath or intraluminal clot, which of the following is not correct?
A. Haire et al showed that a 2 mg dose of alteplase was more effective than urokinase (5000 IU) for the treatment of radiographically proven thrombotic occlusion of a CVC after a dwell time of 120 min.
B. In the COOL trial (Cardiovascular Thrombolytic used to Open Occluded Lines), catheter occlusion was cleared after 120 min in 74% of 69 patients who were given one 2 mg dose of alteplase compared with only 17% of 70 patients given placebo.
C. Current recommendations include delivery of a thrombolytic agent into the catheter lumen with a dwell time of at least 30 min and a repeated dose if needed. If catheter patency is not restored, a low dose of alteplase can be infused over 6—8 h.
D. If treatment with a thrombolytic agent does not clear the catheter, a guide wire should not be inserted through the catheter lumen to dislodge a thrombus at the tip of the CVC.

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2009.07.12 Sun Humanities Quiz: Michel Foucault's The Birth of the Clinic


In Michel Foucault's (米歇爾·福柯) The Birth of the Clinic (1963), it traces the origins of modern medicine in France at the end of the 18th century during the period 1769 - 1825. Which of the following is not discussed in this book?
A. During this time, medical practices based on superstition were replaced by enlightened empirical science. What changed was both how illness and how the doctor was defined and how these terms were related.
B. It also looks at the political, social and institutional changes.
C. For clinical experience to become possible as a form of knowledge, the patient has to be enveloped in a collective homogeneous space, and tthe hospital became necessary, to open up language to a whole new domain, to see and describe, to perform anatomical study, etc - the anatomico-clinical method was developed.
D. Metaphors were used to describe a lot of influential diseases. 

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2009.07.10 What is in place?


Click image to enlarge

What is the red tube through the nostril of this patient?

A. Feeding tube
B. Endobronchial blocker
C. Sengstaken-Blakemore tube
D. Tracheal insufflation tube

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