Sunday, April 30, 2017

Q; How long does the antiseptic effect of Chlorhexidine last after it is applied during procedure prep?


Answer: About 6 hours

In comparison to other antiseptic preps during procedures, Chlorhexidine provides added advantage of its prolonged residual antiseptic effect.

Saturday, April 29, 2017

Question: Psychiatry service asked your help in management of a patient, who is transferred to ICU for Electroconvulsive Therapy (ECT). Which of the following drug may require reversal before initiating (ECT)? 

 A) lithium 
B) any antidepressant
C) any antipsychotic
D) any antihypertensive
E)  benzodiazepine


Answer: E

Most of the patient's prior drugs are safe during administration of ECT therapy, though lithium dose has been advocated to be decreased or on lower edge of therapeutic level 1.  

Benzodiazepines are usually discontinued before ECT therapy, but in those patients who still require them on board, should be transiently reversed just 2-3 minutes prior of ECT therapy with flumazenil. Benzodiazepines may decrease the intensity of the therapeutic ECT seizure.


References:

1.  Dolenc TJ, Rasmussen KG. The safety of electroconvulsive therapy and lithium in combination: a case series and review of the literature. J ECT 2005; 21:165. 


2. Greenberg RM, Pettinati HM. Benzodiazepines and Electroconvulsive Therapy. Convuls Ther 1993; 9:262. 


3. Krystal AD, Watts BV, Weiner RD, et al. The use of flumazenil in the anxious and benzodiazepine-dependent ECT patient. J ECT 1998; 14:5.

Friday, April 28, 2017

Q: How mitral valve orifice area can be guessed depending on clinical symptoms?

Answer: 

  • The normal mitral valve orifice has a cross-sectional area of about 4.0 cm2.
  • Usually patients are asymptomatic till orifice area is reduced to 2 cm2. 
  • Mild symptoms may be present between 2 cm2 and 1.5 cm2.
  • Most patients become symptomatic when mitral valve area is decreased to 1.5 cm2 (moderate/on exertion)
  • If a patient symptoms are apparent, it can be easily guessed that mitral orifice area is at 1.0 cm2 or less. (even with mild exertion)
Combining with heart sounds auscultation, astute physician can predict valve area just on examination.



Thursday, April 27, 2017

Q: 64 year old female admitted in ICU is going for PET scan. Service requested you to keep patient NPO four hours prior to procedure and low carbohydrate diet 24 hours prior to procedure if feasible?


Answer: Hyperglycemia can interfere with PET scan. High serum glucose level competes with the fluorodeoxyglucose (FDG) for the same cell surface receptor and decreases intracellular FDG.


References:


Torizuka T, Clavo AC, Wahl RL. Effect of hyperglycemia on in vitro tumor uptake of tritiated FDG, thymidine, L-methionine and L-leucine. J Nucl Med 1997; 38:382.

Wednesday, April 26, 2017

Q: Once adequate response is obtained from intravenous antibiotic, the choice of oral antibiotic in septic bursitis is? 


 Answer: In Septic bursitis, usual IV antibiotic is either Vancomycin or Cefazolin. Oral conversion to Clindamycin is most appropriate to cover MRSA ( methicillin-resistant S. aureus). Other oral antibiotics which may be used are dicloxacillin, doxycycline, or trimethoprim-sulfamethoxazole.

Tuesday, April 25, 2017

Q: After how many failed attempts of intubations, chances of complications and death rise exponentially?


Answers: 2

In contrast to previously accepted 3 attempts, recently published data showed that after two failed attempts to insert End-Tracheal Tube (ETT), risk of complications and death go high.



Reference: 

 Buis ML, Maissan IM, Hoeks SE, et al. Defining the learning curve for endotracheal intubation using direct laryngoscopy: A systematic review. Resuscitation 2016; 99:63.

Monday, April 24, 2017

Q: What is the dose of lipid emulsion in lidocaine toxicity?


 Answer: Lipid emulsion is suggested for lidocaine or local anesthetic toxicity particularly with cardiac arrhythmia or asystole.  It is a 1.5-mL/kg bolus of 20% lipid emulsion solution, followed by a 0.25-mL/kg per minute infusion for 30 to 60 minutes. The bolus can be repeated 1 to 2 times for continued symptoms.

Modus operandi is via "lipid sink". As lidocaine is lipid-soluble, it may reduce the overall plasma concentration. Another mechanism suggested is fostering of cardiac metabolism by augmenting the fatty acid supply, promoting aerobic metabolism and reducing acidosis,


References: 

1. Mazoit JX, Le Guen R, Beloeil H, Benhamou D. Binding of long-lasting local anesthetics to lipid emulsions. Anesthesiology. 2009;110(2): 380-386. 


2. Weinberg GL. Lipid infusion therapy: translation to clinical practice. Anesth Analg. 2008 May. 106(5):1340-2

Sunday, April 23, 2017

Question: What is Anton's syndrome? 


Answer:  

It's full nomenclature is Anton–Babinski syndrome. It is also called visual anosognosia. It is actually a type of stroke but may confuse staff as a delirium. Anatomically damage is in the occipital lobe, and patients are "cortically blind". Interestingly, patients affirm, that they are capable of seeing, despite clear examination proving blindness. They employ confabulation to fill in the missing sensory input. It is considered as one of the most complexed and poorly understood disease and probably due the fact that damage to the visual cortex results in the inability to communicate with the speech-language areas of the brain. Visual imagery is received but cannot be interpreted; the speech centers of the brain confabulate a response!!!

It is described after CVA, head injury and patients with JC virus.


References:


1. Riddoch G. Dissociation of visual perceptions due to occipital injuries, with especial reference to appreciation of movement. Brain. 1917;40:15–57


2. Misra M, Rath S, Mohanty AB. Anton syndrome and cortical blindness due to bilateral occipital infarction. Indian J Ophthalmol. 1989;37:196.

3. McDaniel KD, McDaniel LD. Anton's syndrome in a patient with posttraumatic optic neuropathy and bifrontal contusions. Arch Neurol. 1991;48:101–105

Saturday, April 22, 2017

Q; Antimicrobial irrigation of the urinary bladder is an effective way of suppressing Urinary Tract Infections (UTI) in chronically catheterized bed bound patients, getting frequent ICU admissions for Urosepsis?

A) True
B) False


Answer: B

Antimicrobial irrigation of the bladder does not treat, prevent or supress urinary tract infection. On the contrary, it has shown to increase the risk of urosepsis as well as increase the antibiotic resistance. This practice should be abandoned, if in use. 



Reference:

Schneeberger PM, Vreede RW, Bogdanowicz JF, van Dijk WC. A randomized study on the effect of bladder irrigation with povidone-iodine before removal of an indwelling catheter. J Hosp Infect 1992; 21:223.

Friday, April 21, 2017

Q: Can steroids be used as an added medicine during 'code' (ACLS) ?  (select one)

A) Yes
B) No

Answer:   A

Actually, some of the studies have been showing role of steroids particularly for In-Hospital-Cardiac-Arrest (IHCA) patients. Though vasopressin is no more a part of ACLS, it has been suggested to give as a "Epi-Vasopressin-Steroid" combo!



References:

1. Mentzelopoulos S, Zakynthinos S, Tzoufi M, et al. Vasopressin, epinephrine, and corticosteroids for in-hospital cardiac arrest. Arch Intern Med. 2009;169:15-24. PMID: 19139319. 

2. Mentzelopoulos S, Malachias S, Chamos C, et al. Vasopressin, steroids, and epinephrine and neurologically favorable survival after in-hospital cardiac arrest: a randomized clinical trial. JAMA. 2013;310(3):270-9. 

3. Varvarousi G, Stefaniotou A, Varavaroussis D, et al. Glucocorticoids as an emergency pharmacologic agent for cardiopulmonary resuscitation. Cardiovasc Drugs Ther. 2014;28:477-88. PMCID: PMC4163188..

Thursday, April 20, 2017

Q: Enhanced external counterpulsation (EECP) is performed during which cycle of the heart? (Select one)

A) Diastole
B) systole


Answer:

EECP relies on the concept of diastolic augmentation i.e. retrograde aortic blood flow during the diastole. It is done by applying cuffs, wrapped around the patient’s legs and providing sequential pressure at about 300 mm Hg from calf  to the lower and upper thighs. It may be used as an adjuvant or  salvage or rescue therapy in angina or congestive heart failure.


Reference:

Feldman AM, Silver MA, Francis GS, et al. Enhanced external counterpulsation improves exercise tolerance in patients with chronic heart failure. J Am Coll Cardiol 2006; 48:1198.

Wednesday, April 19, 2017

Q: What is Warburg effect?

Answer: Warburg effect is the basis of positron emission tomography (PET) scan, and physicians are expected to know it. In normal cells, there is a low rate of glycolysis followed by oxidation of pyruvate in mitochondria. But in tumor cells there is a high rate of glycolysis followed by lactic acid fermentation in the cytosol, producing energy. This continue to happen despite there is no dearth of oxygen in cytosol. This phenomenon leads to enhanced intracellular trapping of the 18-fluoro-2-deoxyglucose (FDG) within tumor cells, that can be seen on the PET scan.



References: 

1. Warburg O (February 1956). "On the origin of cancer cells". Science. 123 (3191): 309–14.

2. Gatenby RA, Gillies RJ (November 2004). "Why do cancers have high aerobic glycolysis?". Nature Reviews. Cancer. 4 (11): 891–9.

3. Kim JW, Dang CV (September 2006). "Cancer's molecular sweet tooth and the Warburg effect". Cancer Research. 66 (18): 8927–30. 

Tuesday, April 18, 2017

Q: 22 year old asian male is admitted to ICU with right flank pain and hematuria. One of the resident raised differential diagnosis of 'Nutcracker Syndrome'. Which one aspect of the history goes against the diagnosis of it?


Answer: Pain on the right side

The nutcracker syndrome (also called the left renal entrapment syndrome) is always on the left side. It may present as either painless hematuria or with left flank pain. It is mostly find in Asian population. It is due to compression of the left renal vein between the aorta and proximal superior mesenteric artery. Treatment includes left renal vein stent, transposition of the superior mesenteric artery or left renal vein, and autotransplantation of the left kidney.


References: 

1.  Zhang H, Li M, Jin W, et al. The left renal entrapment syndrome: diagnosis and treatment. Ann Vasc Surg 2007; 21:198. 

2.  Russo D, Minutolo R, Iaccarino V, et al. Gross hematuria of uncommon origin: the nutcracker syndrome. Am J Kidney Dis 1998; 32:E3. 

3. Shokeir AA, el-Diasty TA, Ghoneim MA. The nutcracker syndrome: new methods of diagnosis and treatment. Br J Urol 1994; 74:139.

Monday, April 17, 2017

Q; Which of the following is the limitation factor in institution of prone positioning in ARDS?

A) Long list of contra-indications
B) patient already on ARDSnet protocol for low tidal volume
C) Patient still in early acute ARDS phase
D) No major trials or evidence based benefit in this area
E) No reduction in ICU days


Answer: A

Except for Choice A, all others do nor exclude institution of prone positioning in ARDS patients. Actually, prone position should be implemented in early ARDS phase (choice C). Prior to implementing prone position, it should be important to apply all know maneuvers with known benefits including low tidal volume as well as low plateau pressure strategies (choice A), and should be continued while patient is proned. Though prone position does not decrease ICU length of stay, it may decrease total ventilators day, if successful (Choice E). There is a major trial called PROVESA, was published in 2013, showing its benefit on patients who become eligible for it (Choice D).



 Reference: 

 Guérin C, Reignier J, Richard JC, et al. Prone positioning in severe acute respiratory distress syndrome. N Engl J Med 2013; 368:2159.

Sunday, April 16, 2017

Q; Looking trend of which electrolyte may provide good survival and prognastic value in cirrhosis patients?


Answer: Sodium

 Hyponatremia is slow but progressive in patients with cirrhosis, and correlates with severity of disease and mortality. It is due to water retention and that's why usually read/graded and correlates with the severity of Ascites. Hyponatremia has been found to be a very powerful predictor of death in patients with cirrhosis and ascites who are on the liver transplant waiting list. Sodium is now officially incorporated in MELD score.


References:

1. Angeli P, Wong F, Watson H, et al. Hyponatremia in cirrhosis: Results of a patient population survey. Hepatology 2006; 44:1535. 

2. Heuman DM, Abou-Assi SG, Habib A, et al. Persistent ascites and low serum sodium identify patients with cirrhosis and low MELD scores who are at high risk for early death. Hepatology 2004; 40:802. 

3. Biggins SW, Rodriguez HJ, Bacchetti P, et al. Serum sodium predicts mortality in patients listed for liver transplantation. Hepatology 2005; 41:32. 

4.Kim WR, Biggins SW, Kremers WK, et al. Hyponatremia and mortality among patients on the liver-transplant waiting list. N Engl J Med 2008; 359:1018.

Saturday, April 15, 2017

Q: Why methanol and ethylene glycol are designated as "primary  alcohols" but isopropyl alcohol  is not?


Answer:  Methanol get oxidized to formic acid. Ethylene glycol get oxidized to glycolic, glyoxylic, and oxalic acids. These acid metabolites cause direct injury and thats why methanol and ethylene glycol are considered primary alcohols.

Isopropyl alcohol metabolized to ketones and cannot be converted to carboxylic acid (formic,  glycolic, glyoxylic, and oxalic acids). Ketones does not cause high an-ion gap acidosis and relatively less injurious than other two.


Friday, April 14, 2017

Q; 58 year old male with history of coronary stents and atrial fibrillation, and on chronic therapy of aspirin, warfarin and Clopidogrel is in ICU again with chest pain. In unrelated clinical scenario, urologist has been consulted and they planned for ureteral stent. Anti-coagulation therapy Should be held till 

 A) INR less than 2 
B) Instead of warfarin, Clopidogrel should be held 
C) No medicine should be held 
D) Advise urology service to avoid ureteral stent 
E) All drugs should be held atleast 48 hours prior to procedure


Answer: C

Actually,  no drug either antiplatelet, or anticoagulation need to be held prior to ureteral stent placement. Although urine should be quickly checked to rule out urinary tract infection.

Thursday, April 13, 2017

Q; Which one of the following is expected in Cholesterol emboli? 

 A) Severe Leukocytosis 
B) Eosinophilia 
C) Triglyceridemia 
 D) Thrombocytopenia 
E) Require must exposure to anticoagulation 


 Answer: B

Particularly in the early phase of cholesterol emboli, majority of the patients develop hypereosinophilia. Though not proven but it is assumed that this is cytokine-mediated via interleukin 5 derived from vascular endothelium.


References: 

1.  Kasinath BS, Lewis EJ.  Eosinophilia as a clue to the diagnosis of atheroembolic renal disease. Arch Intern Med. 1987; 147: 1384–1385.

2. Cecioni I, Fassio F, Gori S, Giudizi MG, Romagnani S, Almerigogna F. Eosinophilia in cholesterol atheroembolic disease. J Allergy Clin Immunol. 2007; 120: 1470–1471;

3. Jucgla A, Moreso F, Muniesa C, Moreno A, Vidaller A. Cholesterol embolism: still an unrecognized entity with a high mortality rate. J Am Acad Dermatol. 2006; 55: 786–793

Wednesday, April 12, 2017


Q: 52 year old male is admitted to ICU with malaise, fever, 30 lbs weight loss and electrolyte imbalance. On exam you noticed multiple seborrheic keratoses, often with an inflammatory base in association with skin tags and acanthosis nigricans. Patient informed you that this skin change happened within last 3 weeks. What is your presumptive diagnosis?


Answer: Sign of Leser-Trelat

It is the sudden appearance of multiple seborrheic keratoses, often with an inflammatory base in association with skin tags and acanthosis nigricans. It raises the strong suspicion of malignancy and a manifestation of paraneoplastic syndromes.




Tuesday, April 11, 2017


Q: How Magnetic Resonance Imaging (MRI) works? 


Answer: MRI uses a magnetic field to align rotating hydrogen protons within the tissue being imaged. During realignment of the protons, energy is released and sampled at different time intervals. The measured signal intensity from this energy depends upon the degree and rate of realignment within a very specific time period, which in turn depends upon the water and fat content of the different tissues. These signals are then converted into gray-scale cross-sectional images that can be depicted in multiple planes or in three dimensions.


Clinical implication: Most diseases manifest themselves by an increase in water content, so MRI is a sensitive test for the detection of disease.


Reference: 

Abi Berger - How does it work? Magnetic resonance imaging -,BMJ. 2002 Jan 5; 324(7328): 35. 

Monday, April 10, 2017

Q; 76 year old male with chronic atrial fibrillation admitted to ICU with shortness of breath. Patient is chronically on amiodarone. CXR is consistent with bacterial pneumonia vs amiodarone toxicity. Which one test may differentiate between bacterial pneumonia and amiodarone toxicity?


Answer:  KL-6

KL-6 gets secreted by proliferating type II pneumocytes. KL-6 is not specific for amiodarone toxicity but it is a sensitive marker in various interstitial lung diseases. KL-6 is a good test for patients who are chronically on amiodarone but develop other disease process like bacterial pneumonia, CHF, or even lung cancer. Reading it with diagnostic tools of other disease markers make it a good test to judge the relative role of amiodarone toxicity in patient's pathology.


References:

1. Endoh Y, Hanai R, Uto K, et al. KL-6 as a potential new marker for amiodarone-induced pulmonary toxicity. Am J Cardiol 2000; 86:229. 

2. Kohno N, Yokoyama A, Kondo K. KL-6 as a serum marker for amiodarone-induced pulmonary toxicity. Intern Med 2000; 39:1004. 

3. Bernal Morell E, Hernández Madrid A, Marín Marín I, et al. [Multiple pulmonary nodules and amiodarone. KL-6 as a new diagnostic tool]. Rev Esp Cardiol 2005; 58:447.

Sunday, April 9, 2017

Case; 48 year old male presented to ICU with massive hemoptysis. Patient was intubated, stabilized and send for arterial embolization. Patient woke up from sedation with paraplegia?


Explanation: In about 5 percent of the population anterior spinal artery arises from a bronchial artery. Proximal embolization of the bronchial artery may cause paraplegia. Extreme caution should be taken and procedure should be performed by an experienced and a  trained intervention radiologist.



Reference: 

Anthony C. Brown, M.D. and Charles E. Ray, M.D., Ph.D. - Anterior Spinal Cord Infarction following Bronchial Artery Embolization - Semin Intervent Radiol. 2012 Sep; 29(3): 241–244

Saturday, April 8, 2017

Q: Describe at least five hemodynamic effects expected from Intraaortic balloon pump counterpulsation (IABP)? 


Answer:

  •  A decrease in SBP (systolic blood pressure) by 20% 
  • An increase in DBP (aortic diastolic blood pressure) by 30%
  • Reduction of Heart rate by 20%
  • A decrease in the Pulmonary Artery Occlusion Pressure(PAOC / Wedge Pressure) by 20% 
  • An increase in the cardiac output (CO) by 20%

Friday, April 7, 2017

Q: Negative pressure wound therapy (NPWT), popularly known as (wound-VAC) increase blood flow due to subatmospheric pressure. At what level of negative pressure it may have reverse effect?


Answer: -175 mm Hg

In NPWT a  portable pump is connected to apply negative suction pressure of -50 to -175 mmHg. This increase the blood flow and helps in healing. Above - 175 mmHg there may be an adverse effect of decreased blood flow.


Reference:


Kairinos N, Voogd AM, Botha PH, et al. Negative-pressure wound therapy II: negative-pressure wound therapy and increased perfusion. Just an illusion? Plast Reconstr Surg 2009; 123:601.

Thursday, April 6, 2017

Q: What is the gold standard test to confirm cholesterol emboli?


Answer: Tissue biopsy

No laboratory testing is specific for cholesterol emboli. Diagnosis can be definitive via debrided tissue or thrombectomy specimen. The histologic hallmark of cholesterol crystal embolism is the presence of "ghosts" of cholesterol crystals or cholesterol clefts within arterioles. This is due to the fact that the convex-shaped crystals within the small arterioles of the kidney dissolve during the fixation process leaving the ghosts.





Reference:

Warren BA, Vales O. The ultrastructure of the stages of atheroembolic occlusion of renal arteries. Br J Exp Pathol 1973; 54:469.

Wednesday, April 5, 2017

Q: Acute shortness of breath and malignant pleural effusions can be a presenting sign of ovarian cancer. What percentage of malignant pleural effusion in ovarian cancer exhibits negative biopsy?


Answer: About 30% 

Actually,  pleural cavity constitutes the most frequent extra-abdominal metastatic site in ovarian carcinoma! But it requires documentation of positive biopsy. About 30% of  malignant pleural effusions may yield false-negative results. If clinical suspicion is there, VATS (video-assisted thoracoscopic surgery)  should be performed. Another advantage or goal of VATS is to quantify pleural tumour burden and intrathoracic cytoreduction.


Reference:

Porcel JM, Diaz JP, Chi DS.- Clinical implications of pleural effusions in ovarian cancer - Respirology. 2012 Oct;17(7):1060-7. 

Tuesday, April 4, 2017

Q: What is "McConnell's sign"?

Answer:  Though describe as an early and specific sign of acute pulmonary embolism (APE), many authorities dispute its specificity related to APE. McConnell's sign is a distinct echocardiographic feature, defined as a regional pattern of right ventricular systolic dysfunction, with akinesia of the mid free wall but sparing of the right ventricular apex.




References: 

López-Candales A, Edelman K, Candales MD. Right ventricular apical contractility in acute pulmonary embolism: the McConnell sign revisited. Echocardiography 2010;27:614–20

Monday, April 3, 2017

Q: Which of the following drug is found to be effective in treatment of acute suicidial ideation, and may be more quicker in response to electroconvulsive therapy (ECT)?


A) Propofol

B) Ketamine
C) Haloperidol
D) Cisatracurium
E) Prozac (fluoxetine)


Answer: B

Oral antidepressants have delayed therapeytic effect and may not be ideal in the treatment of acute suicidal ideation (Choice E). Ketamine has been used as off label for this purpose in Emergency Room or intensive care setting. Ketamine is relatively short but a rapidly acting drug, found to be quicker in action even more than ECT. Due to its side effect it should be used judiciously and under close supervision. A single dose is usually sufficient and can be given intravenously at a dose of 0.5 mg/Kg. It probably works due to its dissociative property.

Propofol (Choice A) may be used as a sedative and may avert the acute situation, but has no direct role. Haloperidol (Choice C) is an anti-psychotic with role in delirium but not an antidepressive. Cisatracurium (Choice D) is a neuromuscular blocker and should be avoided.


References:

1. McGirr A, Berlim MT, Bond DJ, et al. A systematic review and meta-analysis of randomized, double-blind, placebo-controlled trials of ketamine in the rapid treatment of major depressive episodes. Psychol Med 2015; 45:693. 

2. Ghasemi M, Kazemi MH, Yoosefi A, et al. Rapid antidepressant effects of repeated doses of ketamine compared with electroconvulsive therapy in hospitalized patients with major depressive disorder. Psychiatry Res 2014; 215:355. 

3. Murrough JW, Soleimani L, DeWilde KE, et al. Ketamine for rapid reduction of suicidal ideation: a randomized controlled trial. Psychol Med 2015; 45:3571.

Sunday, April 2, 2017

Q; How the choice of temporary dialysis catheter may influence issues with clotting during Continuous Renal Replacement Therapy (CRRT)?


Answer: Depending on manufacturer, temporary dialysis catheter may have either side or end holes. Catheters with end holes are preferable as flow will be laminar, which is optimal and preferred. As expected, flow through the side holes are usually turbulent and down the line may cause stagnation. Also, during CRRT side holes have suctioning against the vessel walls, which may further contribute to the blocking and impairment of flow.


Reference:

Jean G, Chazot C, Vanel T, Charra B, Terrat JC, Calemard E, Laurent G. Central venous catheters for haemodialysis: looking for optimal blood flow. Nephrol Dial Transplant. 1997;12:1689–1691

Saturday, April 1, 2017

Q: Chloramphenicol has an excellent blood brain barrier penetration?

A) True
B) False


Answer: True

Chloramphenicol due to its various side effects is not a drug of choice in most instances and particularly in developed countries. But it remained a valuable drug and in the list of WHO's list of essential medicines due to its excellent blood-brain barrier penetration, far superior to cephalosporins. It has excellent activity against Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae. Many authorities still recommend it as a drug of choice in the treatment of brain abscesses.