Monday, June 18, 2018

Unsuccessful cardioversion in AF

Q: Cardioversion from atrial fibrillation (AF) to normal sinus rhythm (NSR) has low likelihood in the presence of all of the following except?

A) AF continuously present for more than 3 months
B) Markedly enlarged atriums
C) Pneumonia
D) Thyrotoxicosis
E) Mitral valve disease


Answer:  A

If underlying diseases are not treated (choices C, D and E), chances of successful cardioversion from AF to NSR remains low. Markedly enlarged atriums with left atrium having dimension >6.0 cm or right atrium having dimension >37 mm may also be a hindrance in this process (choice B). 3

Time period described to make successful cardioversion from AF to NSR is to be present continuously for about one year.

#cardiology


References: 

1. Elhendy A, Gentile F, Khandheria BK, et al. Predictors of unsuccessful electrical cardioversion in atrial fibrillation. Am J Cardiol 2002; 89:83. 

2. Dittrich HC, Erickson JS, Schneiderman T, et al. Echocardiographic and clinical predictors for outcome of elective cardioversion of atrial fibrillation. Am J Cardiol 1989; 63:193. 

3. Henry WL, Morganroth J, Pearlman AS, et al. Relation between echocardiographically determined left atrial size and atrial fibrillation. Circulation 1976; 53:273. 

Sunday, June 17, 2018

Diabetic Osteomyelitis

Q: 66 year old male with past medical history of diabetes mMellitus, sensory and autonomic neuropathy, diabetic nephropathy and peripheral arterial disease is admitted to ICU with septic shock. All of the following features support the diagnosis of osteomyelitis except

A) Ability to probe to bone
B) Ulcer size larger than 5 cm2
C) 'Sausage toe'
D) Erythrocyte sedimentation rate (ESR) >70 mm/h
E) High initial radiographic suspicion


Answer: B

All of the above choices highly support the diagnosis of osteomyelitis due to uncontrolled diabetes except the choice B. Ulcer size larger than 2 cm2 is sufficient to support the diagnosis of diabetic osteomyelitis in the presence of other features. 

The objective of above question is to make the emphasis on cost-effective and clinical diagnosis of diabetic osteomyelitis. Though magnetic resonance imaging (MRI) has high sensitivity and specificity for the diagnosis of osteomyelitis, but if the history and clinical findings 3, 4 are present with highly supportive simple radiographic evidence (choice E), MRI may not be needed.

#infectiousdisease
#physicalexam



References:

1. Lipsky BA, Berendt AR, Cornia PB, et al. 2012 Infectious Diseases Society of America clinical practice guideline for the diagnosis and treatment of diabetic foot infections. Clin Infect Dis 2012; 54:e132.

2. Butalia S, Palda VA, Sargeant RJ, et al. Does this patient with diabetes have osteomyelitis of the lower extremity? JAMA 2008; 299:806.

3. Dinh MT, Abad CL, Safdar N. Diagnostic accuracy of the physical examination and imaging tests for osteomyelitis underlying diabetic foot ulcers: meta-analysis. Clin Infect Dis 2008; 47:519.

4.  Rajbhandari SM, Sutton M, Davies C, et al. 'Sausage toe': a reliable sign of underlying osteomyelitis. Diabet Med 2000; 17:74.

Saturday, June 16, 2018

Copper deficiency

Q: Copper is absorbed in?

A) Stomach and proximal duodenum
B) Small intestine
C) Transverse colon
D) Sigmoid colon 
E) Rectum


Answer:  A

Copper is absorbed in the stomach and proximal duodenum. Clinical significance of this question is to address the need of elemental supplements post bariatric surgeries like Roux-en-Y gastric bypass (RYGB) or biliopancreatic diversion with duodenal switch (BPD/DS) surgeries. Deficiency of copper leads to microcytic anemia, neutropenia, and ataxia.

#surgicalcriticalcare



References: 

 1. Griffith DP, Liff DA, Ziegler TR, et al. Acquired copper deficiency: a potentially serious and preventable complication following gastric bypass surgery. Obesity (Silver Spring) 2009; 17:827. 

2. Gletsu-Miller N, Broderius M, Frediani JK, et al. Incidence and prevalence of copper deficiency following roux-en-y gastric bypass surgery. Int J Obes (Lond) 2012; 36:328.

Friday, June 15, 2018

Allen test for lower extremity

Q: The Allen's test should be performed before inserting arterial line catheter in

A) Radial artery 
B) Dorsalis pedis artery 
C) Brachial artery 
D) Femoral artery
E) A and B


Answer: E

It is well known that Allen or modified Allen test should be performed prior to insertion of arterial line in radial artery to assess the collateral circulation via ulnar artery. Similarly, Allen test should be performed if arterial line needs to be inserted in dorsalis pedis artery to assess collateral circulation via posterior tibial artery. It is performed by elevating the lower extremity until the plantar skin blanches followed by compression of dorsalis pedis artery and lowering of extremity to dependency. The foot rapidly resumes color if the posterior tibial artery flow is adequate. Allen test for lower extremity has also been described with  Doppler signals.

#procedures



Reference: 


Haddock N.T., Garfein E.S., Saadeh P.B., Levine J.P. (2009) The lower-extremity allen test. Journal of Reconstructive Microsurgery, 25 (7) , pp. 399-403.

Thursday, June 14, 2018

Acute headache

Q: Which of the following is of the highest priority in an approach to the urgent evaluation of an acute headache?

A) Carbon Monooxide (CO) poisoning
B) Subarachnoid hemorrhage
C) Meningitis
D) Giant cell (temporal) arteritis
E) Optic neuritis


Answer: A

Indeed all of the above conditions require immediate attention but carbon mono-oxide exposure is top on the list due to the fact that if not treated promptly or misdiagnosed, may result in a very rapid death of the patient. And, it is easy to treat with 100% oxygen therapy. CO diffuses rapidly across the pulmonary capillary membrane and binds to the iron moiety of heme with 240 times the affinity of oxygen. 

#toxicity
#neurology



 References:

1. Hampson NB. U.S. Mortality Due to Carbon Monoxide Poisoning, 1999-2014. Accidental and Intentional Deaths. Ann Am Thorac Soc 2016; 13:1768.


2. Approach to the urgent evaluation of headache in an adult - © 2018 UpToDate, Inc. link here

Wednesday, June 13, 2018

Synchronized Cardioversion

Q: Synchronized electrical cardioversion is targeted to which part of the electrocardiogram (EKG) cycle? 

A) P wave
B) PR interval
C) QT interval
D) QRS complex
E) T wave


Answer: D


Cardiac cycle has a vulnerable and a refractory period. The refractory period is during the QRS complex, and the vulnerable period is during the T wave. Application of electrical cardioversion during vulnerable period may induce ventricular fibrillation.

#procedure
#cardiology



Reference:

Link, M. Arkins D. 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2010, Volume 122, Issue 18 suppl 3 :: http://circ.ahajournals.org/content/122/18_suppl_3/S706.full#sec-24

Tuesday, June 12, 2018

Cryptogenic stroke

Q; Cryptogenic stroke (CS) requires the documentation of atrial fibrillation?

A)True
B) False


Answer: False

Cryptogenic stroke is a diagnosis of exclusion. In fact, definition of cryptogenic stroke is an ischemic stroke without any well-defined etiology, including any cardiac source.

Various possible causes for CS has been proposed including undocumented occult paroxysmal atrial fibrillation (AF), paradoxical embolism via patent foramen ovale (PFO), atrial septal defect (ASD), ventricular septal defect (VSD, or via pulmonary arteriovenous malformation (AVM). Other causes include undefined hypercoagulable state due to antiphospholipid antibodies, occult cancer causing hypercoagulabe state and vasculopathies.

#cardiology
#neurology


References:

1. Saver JL. CLINICAL PRACTICE. Cryptogenic Stroke. N Engl J Med 2016; 374:2065. 

2.  Hart RG, Diener HC, Coutts SB, et al. Embolic strokes of undetermined source: the case for a new clinical construct. Lancet Neurol 2014; 13:429.

Monday, June 11, 2018

Ferritin

Q: Which of the following is an acute phase reactant (select one)

A) Serum ferritin
B) Transferrin 


Answer: A

Ferritin is mostly described with the metabolism of iron and in discussion with iron deficiency and iron overload. Ferritin is an indirect marker of the total stored iron in the body. But it is also an acute phase reactant and its level may be increased in inflammation, infection or cancer. The objective of above question is to highlight the point that measuring ferritin to rule out iron deficiency anemia in ICU patients may not be a reliable test.


#hematology
#SIRS


References:

1. Zandman-Goddard G, Shoenfeld Y. Ferritin in autoimmune diseases. Autoimmun Rev. 2007;6:457–463.

2. Weinberg ED, Miklossy J. Iron withholding: a defense against disease. J Alzheimers Dis. 2008;13:451–463.

3. Wang W, Knovich MA, Coffman LG, Torti FM, Torti SV. Serum Ferritin: Past, Present and Future. Biochimica et biophysica acta. 2010;1800(8):760-769. 

Sunday, June 10, 2018

HSV-1 encephalitis

Q: Why Herpes Simplex Virus (HSV)-1 encephalitis is not much common in immunocompromised patients despite high occurrence of mucocutaneous HSV-1 infections in these patients? 


 Answer:  Herpes Simplex Virus (HSV)-1 encephalitis is not much common in immunocompromised patients because most of the brain damage from CNS HSV-1 infection is immune mediated. In immunocompromised patient it has only a mild histopathologic changes.

#infectiousdiseases 
#neurology


Reference:

Pepose JS, Hilborne LH, Cancilla PA, Foos RY. Concurrent herpes simplex and cytomegalovirus retinitis and encephalitis in the acquired immune deficiency syndrome (AIDS). Ophthalmology 1984; 91:1669.

Saturday, June 9, 2018

Caprini risk score

Q: What is Caprini risk score?

Answer: The Caprini risk score is a risk assessment tool for the occurrence of venous thromboembolism (VTE) among surgical patients. It comprehensively takes into account of many variables including

  •  Stroke (in last four weeks)
  •  Fracture of the hip, pelvis, or leg
  •  Elective arthroplasty or Arthroscopic surgery
  •  Acute spinal cord injury (in last four weeks)
  •  Age
  •  Prior episodes of VTE
  • Positive family history for VTE
  • Prothrombin 20210 A
  • Factor V Leiden
  •  Lupus anticoagulants
  • Anticardiolipin antibodies
  •  High homocysteine in the blood
  • Heparin-induced thrombocytopenia
  • Other congenital or acquired thrombophilia
  • Laparoscopy lasting more than 45 minutes
  • General surgery lasting more than 45 minutes
  • Cancer
  • Plaster cast
  • Bedbound for more than 72 hours
  • Central venous access
  • BMI > 25 Kg/m2
  • Edema in the lower extremities
  • Varicose veins
  • Pregnancy
  • Post-partum
  • Oral contraceptive or Hormonal therapy
  • Unexplained or recurrent abortion
  • Sepsis (in last four weeks)
  • Serious lung disease (abnormal PFT) or pneumonia (in last four weeks) 
  • Acute myocardial infarction
  • Congestive heart failure
  • Bed rest
  • Inflammatory bowel disease


Score 0-1: Low risk of VTE
Score 2: Moderate of VTE
Score 3-4: High risk of VTE
Score ≥ 5: Highest risk for VTE


Online calculators are easily available at various search engines.



References:

1. Caprini JA, Arcelus JI, Hasty JH, Tamhane AC, Fabrega F (1991). "Clinical assessment of venous thromboembolic risk in surgical patients.". Semin Thromb Hemost. 17 Suppl 3: 304–12. 

2. Caprini JA (2005). "Thrombosis risk assessment as a guide to quality patient care.". Dis Mon. 51 (2-3): 70–8.

Friday, June 8, 2018

steroid induced myopathy and liver transplant

Q: Which organ transplant patients are relatively more prone to steroid induced myopathy?

A) Kidney
B) Heart
C) liver
D) Lung
E) Pancreas 


Answer: C

About seven percent of patients may develop acute critical illness myopathy after liver transplant (OLT). As expected risk factors include severity of illness, dialysis requirement, and higher doses of glucocorticoids. Carnitine deficiency in liver failure patients is advocated as a contributory factor in these patients.

#transplantation
#hepatology


Reference:

Campellone JV, Lacomis D, Kramer DJ, et al. Acute myopathy after liver transplantation. Neurology 1998; 50:46.

Thursday, June 7, 2018

Anticoagulation in unprovoked proximal DVT

Q; 44 years old male is admitted to ICU with shortness of breath and diagnosed having a pulmonary embolism. Patient has a healthy lifestyle and no risk factors are identified. The patient responded well to intravenous heparin without any tendency to bleeding. Workup till discharge from ICU remained negative except proximal lower extremity deep venous thrombosis (DVT). Hematology service declared it as an "unprovoked DVT". The patient will require anticoagulation for?

A) 3 months
B) 6 months
C) 12 months
D) indefinite
E) Till discharge from hospital


Answer:   D

The estimated risk of recurrence following stopping of anticoagulation in patients with a first unprovoked episode of proximal DVT or PE is 10 percent at twelve months and 30 percent at five years. Full anticoagulation reduces the risk of recurrence by 90 percent. In a healthy patient who has no risk for an increased bleed, benefit of anticoagulation outweighs the risk of bleeding.

#pulmonary
#hematology


References:

1. Baglin T, Bauer K, Douketis J, et al. Duration of anticoagulant therapy after a first episode of an unprovoked pulmonary embolus or deep vein thrombosis: guidance from the SSC of the ISTH. J Thromb Haemost 2012; 10:698. 


2. Kearon C, Akl EA, Ornelas J, et al. Antithrombotic Therapy for VTE Disease: CHEST Guideline and Expert Panel Report. Chest 2016; 149:315.

3. Patients with a first symptomatic unprovoked deep vein thrombosis are at higher risk of recurrent venous thromboembolism than patients with a first unprovoked pulmonary embolism. J Thromb Haemost 2010; 8:1926. 

4. Couturaud F, Sanchez O, Pernod G, et al. Six Months vs Extended Oral Anticoagulation After a First Episode of Pulmonary Embolism: The PADIS-PE Randomized Clinical Trial. JAMA 2015; 314:31. 

5. Kyrle PA, Kammer M, Eischer L, et al. The long-term recurrence risk of patients with unprovoked venous thromboembolism: an observational cohort study. J Thromb Haemost 2016; 14:2402. 

Wednesday, June 6, 2018

QT Interval

Q: Which leads have the longest QT interval?


Answer: Leads V2 and V3

QT intervals vary significantly among different EKG leads. Leads V2 and V3 usually has the longest QT measurements. This simultaneously make these leads most favorable as well as unfavorable, as they are more precise giving the longest measurement but at the same time can deceive due to presence of U waves in these leads  (particularly in adolescents).

#cardiology


Reference:

Cowan JC, Yusoff K, Moore M, et al. Importance of lead selection in QT interval measurement. Am J Cardiol 1988; 61:83.

Tuesday, June 5, 2018

Risk factors for recurrence of ICH

Q: Out of the following risk factors which one is the most important risk factor for recurrence of intracranial hemorrhage (ICH)?

A) Uncontrolled hypertension 
B) Lobar location of initial ICH 
C) Male gender 
D) Ongoing anticoagulation 
E) Greater number of microbleeds on MRI 


Answer: A

Objective of the above question is two-folds. First is to emphasize that the simple strategy to control blood pressure is the most promising way to avoid recurrence of ICH. Second is to emphasize that the patients can be re-started on anticoagulation if needed though very close monitoring and discussion about risks vs benefits is required. Most patients once out of the acute period can tolerate anticoagulation if necessary. In long run, uncontrolled blood pressure is the biggest risk factor for the recurrence of ICH.

#neurology
#cardiology



References:

1. Chen ST, Chiang CY, Hsu CY, et al. Recurrent hypertensive intracerebral hemorrhage. Acta Neurol Scand 1995; 91:128

2. Huhtakangas J, Löppönen P, Tetri S, et al. Predictors for recurrent primary intracerebral hemorrhage: a retrospective population-based study. Stroke 2013; 44:585. 

3. Kase CS, Kurth T. Prevention of intracerebral hemorrhage recurrence. Continuum (Minneap Minn) 2011; 17:1304. 


Monday, June 4, 2018

VTE prophylaxis in SCI

Q: Prophylaxis to prevent deep venous thrombosis and pulmonary embolism - VTE - should be continued for at least how long after spinal cord injuries (SCI)?

A) Two weeks
B) Four weeks
C) Three months
D) Six months
E) Indefinite


Answer: C

In patients with acute SCI, after considering all risks and benefits, usual recommended duration for VTE prophylaxis is about three months. Ideally, pharmacologic intervention with low molecular weight heparin (LMWH) is recommended but warfarin with Internationalized Normalized Ratio (INR) of 2 to 3 is also acceptable.

#trauma



References:

1. Paralyzed Veterans of America. Consortium for Spinal Cord Medicine. Prevention of Thromboembolism in individuals with Spinal Cord Injury. Clinical practice guideline for healthcare providers. 3rd Edition. 2016. 

2. Ploumis A, Ponnappan RK, Maltenfort MG, et al. Thromboprophylaxis in patients with acute spinal injuries: an evidence-based analysis. J Bone Joint Surg Am 2009; 91:2568.

Sunday, June 3, 2018

Ischemic cholangiopathy after liver transplant

Q: What could be the risk to the transplanted liver with the use of a non-heart beating donor graft?



Answer: Ischemic cholangiopathy

Blood supply to the major bile ducts comes exclusively from the hepatic artery via the peribiliary plexus. Ischemic cholangiopathy mostly happened after liver transplantation, particularly with the use of a non-heart beating donor graft.

#transplantation
#hepatology


References:

1. de Vries Y, von Meijenfeldt FA, Porte RJ. Post-transplant cholangiopathy: Classification, pathogenesis, and preventive strategies. Biochim Biophys Acta 2018; 1864:1507. 

2. Mourad MM, Algarni A, Liossis C, Bramhall SR. Aetiology and risk factors of ischaemic cholangiopathy after liver transplantation. World J Gastroenterol 2014; 20:6159. 

3. Cameron AM, Busuttil RW. Ischemic cholangiopathy after liver transplantation. Hepatobiliary Pancreat Dis Int 2005; 4:495.

Saturday, June 2, 2018

Mycotic Aneurysm

Q: Out of the following which organism is most likely to cause a mycotic aneurysm and diseased aorta is most vulnerable to it? 

A) Salmonella 
B) Listeria 
C) Yersinia 
D) Haemophilus influenzae 
E) Clostridium septicum


Answer:  A

Staphylococcus spp and Salmonella spp are the most common organisms to most likely cause a mycotic aneurysm. For not an absolutely clear reason, the diseased aorta is relatively found to be more vulnerable to Salmonella and is isolated in the bacteremic seeding of atherosclerotic plaque.

All others are less common causes of a mycotic aneurysm.

#infectious diseases
#cardiology



References:

1.  Brossier J, Lesprit P, Marzelle J, et al. New bacteriological patterns in primary infected aorto-iliac aneurysms: a single-centre experience. Eur J Vasc Endovasc Surg 2010; 40:582. 

2. Marques da Silva R, Caugant DA, Eribe ER, et al. Bacterial diversity in aortic aneurysms determined by 16S ribosomal RNA gene analysis. J Vasc Surg 2006; 44:1055. 

Friday, June 1, 2018

uremic bleeding

Q: 58 year old male with End Stage Renal Disease (ESRD) is back from OR after coronary artery bypass (CABG). Patient had issue with severe uremic coagulopathy in OR for which Desmopressin (DDAVP) was given twice. Also patient required pRBC transfusions along with platelets, Fresh Frozen Plasma (FFP), Four-Factor Prothrombin Complex Concentrate (4F-PCC) and Cryoprecipitate. Patient had his session of hemodialysis a night before surgery. Postoperative his coagulation profiles are in normal range. Patient is hemodynamically unstable requiring multiple vasopressors and not stable to start continuous renal replacement therapy (CRRT). Which of the following agent can be used for his uremic platelet dysfunction?

A) Factor 7 (2 mg)

B) Repeat dose of 4F-PCC
C) intravenous Estrogen
D) Repeat dose of Desmopressin
E) intrinsic Nitric oxide (iNO)



Answer: C

Though estrogen is commonly used as a long term therapy for uremic platelet disorder but there are reports of its use in acute setting. Intravenous form of estrogen can be effective within six hours, and can be used in extreme situations where all other options have been exhausted. 

Out of all of the above choices, estrogen is the only answer by exclusion.

- Factor 7 has no role in uremic bleeding. Also, it may occlude the coronary grafts (choice A). 
- Repeating 4F-PCC would not be very useful if all coagulation profiles are normal (choice B). 
- DDAVP develop tachyphylaxis quickly and is usually not effective after two doses, which patient has already received in OR (choice D). 
- iNO has no role in uremic bleeding (choice E).


#hematology
#surgicalcriticalcare
#nephrology

References:


1. Livio M, Mannucci PM, Viganò G, et al. Conjugated estrogens for the management of bleeding associated with renal failure. N Engl J Med 1986; 315:731.

2. Heunisch C et al. (1998) Conjugated estrogens for the management of gastrointestinal bleeding secondary to uremia of acute renal failure. Pharmacotherapy 18: 210-217

Thursday, May 31, 2018

Deep veins of lower extremity

Q: All of the following are deep veins in lower extremity except?

A) Small saphenous vein 

B) Common iliac vein 
C) Deep femoral vein 
D) Superficial femoral vein
E) Popliteal vein 


Answer:  A

The objective of above question is to highlight the misnomer of the superficial femoral vein (choice D). It is a deep vein and its thrombosis should be considered as a deep venous thrombosis. Fortunately, all recent texts have omitted superficial from 'superficial femoral vein'.  Misnomer may be due to the fact that it is relatively superficial to deep femoral vein but still, it is part of all deep veins of the lower extremity, and should be addressed only as 'femoral vein'.

Out of all of the above choices, only small saphenous vein (choice A) is a superficial vein of the lower extremity.

(S for superficial and S for saphenous!)

#cardiovascular


Reference:

Dong-Kyu Lee, Kyung-Sik Ahn, Chang Ho Kang, Sung Bum Cho. Ultrasonography of the lower extremity veins: anatomy and basic approach. Ultrasonography 2017; 36(2): 120-130.

Wednesday, May 30, 2018

Modified Valsalva Maneuver

Q: What is "modified Valsalva maneuver"? 


Answer:

In normal Valsalva maneuver the patient either in a supine or semirecumbent position is asked to  exhale forcefully against a closed glottis after a normal inspiratory effort (technically should be at 40 mmHg pressure) for about 15 seconds. Good Valsalva maneuver is marked by neck vein distension and increased abdominal wall muscles tone. 

Modified Valsalva maneuver, which involves the standard Valsalva maneuver in the semirecumbent position is followed by supine repositioning with 15 seconds of passive leg raise at a 45 degree angle.

It is claimed that modified Valsalva maneuver is more successful in restoring normal sinus rhythm in supra-ventricular tachycardia (SVT).

#cardiology


Reference: 

Appelboam A, Reuben A, Mann C, et al. Postural modification to the standard Valsalva manoeuvre for emergency treatment of supraventricular tachycardias (REVERT): a randomised controlled trial. Lancet 2015; 386:1747.

Tuesday, May 29, 2018

takotsubo cardiomyopathy

Q: Anticoagulation in patients with stress (takotsubo) cardiomyopathy with 'clean coronaries' is an absolute contraindication? 

A) True
B) False


Answer: B

Stress cardiomyopathy, famously also known as takotsubo cardiomyopathy or 'broken heart syndrome', is a transient condition and mostly recovers with supportive treatment. But it requires anticoagulation despite clean coronaries on cardiac angiogram under two conditions:

1. If there is an intraventricular thrombus present, or
2. if  LV ejection fraction is less than 30 percent despite no thrombus.

Length of anticoagulation is usually 12 weeks but may vary from patient to patient depending on clinical and echocardiographic recovery.


#cardiology


References: 

1. Heik SC, Kupper W, Hamm C, et al. Efficacy of high dose intravenous heparin for treatment of left ventricular thrombi with high embolic risk. J Am Coll Cardiol 1994; 24:1305. 


2. Templin C, Ghadri JR, Diekmann J, et al. Clinical Features and Outcomes of Takotsubo (Stress) Cardiomyopathy. N Engl J Med 2015; 373:929.

Monday, May 28, 2018

Hydration in ICH

Q: All of the following are part of first 24 hours treatment in patients with intracranial hemorrhage (ICH) except

A) Treat fever and try to achieve normothermia
B) Treat hyperglycemia and keep serum glucose level below 180 mg/dL
C) DVT prophylaxis via intermittent pneumatic compression
D) IV hydration with 0.45% sodium chloride (half normal saline)
E) Keep NPO to avoid aspiration pneumonia



Answer: D

Hydration with half normal saline should be avoided. Instead normal saline (0.9% sodium chloride) should be used which is isotonic Hypotonic fluids may make cerebral edema worse and may increase intracranial pressure. Similarly, normovolemia should be the target as hypervolemia may also worsen cerebral edema.

#trauma
#neurology



Reference:

Manno EM. Update on intracerebral hemorrhage. Continuum (Minneap Minn) 2012; 18:598.

Sunday, May 27, 2018

Klüver-Bucy syndrome

Q: What is Klüver-Bucy syndrome (KBS)? 

Answer:  Klüver-Bucy syndrome (KBS) is one of the behavioral manifestations which may occur in Herpes Simplex Virus (HSV) encephalitis. As HSV has affinity to temporal lobe and limbic system, this syndrome manifests with some interesting symptoms like loss of normal anger and fear responses, accompanied by hypersexual activity. KBS is also known as "psychic blindness."


Reference: 

Hart RP, Kwentus JA, Frazier RB, Hormel TL. Natural history of Klüver-Bucy syndrome after treated herpes encephalitis. South Med J 1986; 79:1376.

Saturday, May 26, 2018

Steroid Induced Myopathy

Q: Which of the following subset of patients are more prone to respiratory muscle weakness from steroid induced myopathy?

A) End Stage Renal Disease (ESRD)
B) Cancer
C) Diabetes
D) Neuro-trauma
E) Congestive Heart Failure (CHF)


Answer: B

For reason not entirely clear but steroid induced myopathy manifests differently in patients who have a systemic malignancy, with tendency towards involvement of the respiratory muscles. This may make them more prone to respiratory infections due to decrease ability to clear secretions, cough and protect the airway.


#pulmonary
#oncology


Reference:


Batchelor TT, Taylor LP, Thaler HT, et al. Steroid myopathy in cancer patients. Neurology 1997; 48:1234.

Friday, May 25, 2018

Autonomic Dysreflexia in SCI

Q: Autonomic dysreflexia can be a major clinical issue after spinal cord injuries (SCI) above which level? 

A) T6 
B) T11 
C) L1 
D) S1
E) At any level of SCI 



Answer: A

Autonomic dysreflexia can be a major clinical issue after spinal cord injuries (SCI) above T6. This is due to loss of coordinated autonomic responses on heart rate and vascular tone. Uninhibited sympathetic responses to stimuli (such as urinary bladder distention, constipation, pressure ulcers, sexual arousal, labor, and delivery) below the level of the injury lead to diffuse vasoconstriction and hypertension, and a compensatory, but not enough, parasympathetic response producing bradycardia and vasodilation above the level of the lesion. It is manifested by a headache, diaphoresis, hypertension. flushing, anxiety, nausea, and bradycardia. In its worst form, it can cause intracranial hemorrhage and seizures. Also,  hypertensive crisis complicated by bradycardia may lead to cardiac arrest. The severity and frequency of attack correlate with the severity of the SCI.

Point of learning to this question is to highlight the importance of level T6 in SCI as below this level intact splanchnic innervation allows for compensatory dilatation of the splanchnic vascular bed. 


Reference:

1. Bycroft J, Shergill IS, Chung EA, et al. Autonomic dysreflexia: a medical emergency. Postgrad Med J 2005; 81:232. 

Thursday, May 24, 2018

Total Artificial Heart

Q: To receive Total Artificial Heart (TAH), what is the basic anatomical requirement?


Answer:  In contrast to other non-pulsatile cardiac devices, TAH is a pulsatile device. Due to it's larger size, patient need to have an adequate body habitus documented on CT scan of chest with a 
  •  body-surface area of >1.7 or
  •  a distance of ≥10 cm from the 10th anterior vertebral body to the inner table of the sternum 


Reference:

Meyer A, Slaughter M. The total artificial heart. Panminerva Med 2011; 53:141.

Wednesday, May 23, 2018

Glucagon side effect

Q: 52 year old male presented with Propranolol (Beta blocker) overdose. While writing orders for glucagon, which of the following medicine is recommended to administer concurrently?

A) Anti-emetic
B) Antibiotics
C) Steroids
D) Calcium channel blockers
E) Anti-seizure


Answer: A

Glucagon administration can induce severe emesis and it is recommended to administer a serotonin antagonist antiemetic such as ondansetron as a prophylaxis. Similarly diarrhea can also become an issue and patient may require anti-diarrheal but it is not recommended to administer concurrently with beta blocker.


Steroids, antibiotics and anti-seizure drugs have no role in beta blocker overdose.

Calcium channel blockers may make hypotension and bradycardia worse due to beta blocker overdose.


#toxicology
#pharmacology



References:


1. Ranganath L, Schaper F, Gama R, Morgan L. Mechanism of glucagon-induced nausea. Clin Endocrinol (Oxf). 1999 Aug;51(2):260-1. 


2. Bettge K, Kahle M, Abd E, Aziz MS, Meier JJ, Nauck MA. Occurrence of nausea, vomiting and diarrhoea reported as adverse events in clinical trials studying glucagon-like peptide-1 receptor agonists: A systematic analysis of published clinical trials. Diabetes Obes Metab. 2017 Mar;19(3):336-347.  Epub 2016 Dec 19. 

Tuesday, May 22, 2018

viral blips

Q: What does it mean by viral "blips"?


Answer: Viral "blips" is a phenomenon in HIV treatment where isolated incidents of low-level of detectable HIV RNA (50 to 200 copies/mL) occurs during the course of treatment despite full compliance from a patient. Reasons for these blips are not fully understood but they are either lab errors or release of virions not related to active viral replication. Mostly these blips are clinically insignificant, though there is some evidence that it may indicate an increased risk for virologic failure and predict future treatment failure. 

On a similar note, Patients with HIV who develop critical illness may have a transient increase in the viral load. Also, vaccinations can cause a transient increase in the viral load.

#infectiousdiseases


References:

1. Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Department of Health and Human Services. http://aidsinfo.nih.gov/contentfiles/lvguidelines/AdultandAdolescentGL.pdf 

2. Nettles RE, Kieffer TL, Kwon P, et al. Intermittent HIV-1 viremia (Blips) and drug resistance in patients receiving HAART. JAMA 2005; 293:817. 

3. Gallant JE. Making sense of blips. J Infect Dis 2007; 196:1729. 

4. Laprise C, de Pokomandy A, Baril JG, et al. Virologic failure following persistent low-level viremia in a cohort of HIV-positive patients: results from 12 years of observation. Clin Infect Dis 2013; 57:1489.

Monday, May 21, 2018

Refractory toxicity of atypical antipsychotics

Q: Which of the following is a choice of treatment in refractory cases of toxicity from atypical antipsychotics?

A) Hemodialysis (HD)
B) Continuous Renal Replacement Therapy (CRRT)
C) Bicarbonate infusion
D) Lipid emulsion therapy
E) Hyperbaric oxygen


Answer: D

Although evidence is weak but lipid emulsion therapy is the only known effective treatment for refractory toxicity from atypical antipsychotics.

Unlike most drug overdoses HD and CRRT are not effective and so far has no role in such clinical scenarios.

Bicarbonate is an effective treatment for tricyclic antidepressants overdose but not for an overdose of atypical antipsychotics.

Using hyperbaric oxygen would be a malpractice!


References:

1. Bartos M, Knudsen K. Use of intravenous lipid emulsion in the resuscitation of a patient with cardiovascular collapse after a severe overdose of quetiapine. Clin Toxicol (Phila) 2013; 51:501.

2. Yurtlu BS, Hanci V, Gür A, Turan IO. Intravenous lipid infusion restores consciousness associated with olanzapine overdose. Anesth Analg 2012; 114:914.

Sunday, May 20, 2018

Contrast Induced Nephropathy

Q: Which of the following is the risk factor for Contrast Induced Nephropathy (CIN)

A) Hyperglycemia
B) Hypoglycemia


Answer: A

The important point to remember is that hyperglycemia increases the risk of CIN independent of a diagnosis of diabetes mellitus (DM) in a proportionally incremental manner! The mechanism for this independent risk from hyperglycemia without any association with DM is not fully understood but probably it is due to the osmotic effect of glucose.


#Nephrology



Reference:

Stolker JM, McCullough PA, Rao S, et al. Pre-procedural glucose levels and the risk for contrast-induced acute kidney injury in patients undergoing coronary angiography. J Am Coll Cardiol 2010; 55:1433.

Saturday, May 19, 2018

Gestational Thrombocytopenia

Q: Gestational thrombocytopenia  is characterized by all of the following except?

A) Platelet count is usually between 100,000 to 150,000/microL
B) No increased risk of bleeding or bruising
C) No risk of fetal thrombocytopenia
D) It is a diagnosis of exclusion
E) It may require plasmapheresis soon after delivery


Answer: E

Objective of the above question is to highlight the differential diagnosis between relatively benign gestational thrombocytopenia from other dreaded complications such as HELPP syndrome (Hemolysis with a microangiopathic blood smear, Elevated Liver enzymes, and a Low Platelet count).

#1 point of learning: if the platelet count is less than 80,000/microL, it should be evaluated more closely as gestational thrombocytopenia is usually benign (Choice A).

#2 point of learning: It should be approached as a diagnosis of exclusion due to high morbidity risk from other thrombocytopenias (choice D).

Gestational thrombocytopenia is usually benign and get resolve with end of pregnancy (Choices A,B and E)

#hematology
#obgyn



References:

1.  Reese JA, Peck JD, McIntosh JJ, et al. Platelet counts in women with normal pregnancies: A systematic review. Am J Hematol 2017; 92:1224.

2. Jaschevatzky OE, David H, Bivas M, et al. Outcome of pregnancies associated with marked gestational thrombocytopenia. J Perinat Med 1994; 22:351. 

Friday, May 18, 2018

Egg allergy and Flu vaccine

Q: 72 year old male is improving in ICU after community-acquired pneumonia requiring ventilatory support. Flu vaccination is suggested by an automated pop up on Electronic Medical Record (EMR). Patient has a history of anaphylaxis to egg. Should Flu vaccine be administered?

A) Yes 
B) No


Answer:  Yes 

Though it is true that most inactivated influenza vaccines (IIVs), as well as live-attenuated influenza vaccines (LAIVs), contain a small amount of egg protein but over the years in all new vaccines the amount of egg protein has decreased so significantly that even patients with a history of anaphylaxis to egg can safely receive flu vaccination. Skin testing or standard questionnaire for egg allergy is no longer required to administer flu vaccine. 

To note: allergy to egg should not be equivalated to the previous reaction to the flu vaccine. Such patients should be consulted beforehand by an allergy specialist as it may be due to another component of a vaccine.




Reference:

Grohskopf LA, Sokolow LZ, Broder KR, et al. Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices - United States, 2017-18 Influenza Season. MMWR Recomm Rep 2017; 66:1.

Thursday, May 17, 2018

Cholesterol Emboli

Q: Which of the following has shown to be beneficial in cholesterol embolic disease?

A) Hemodialysis (HD)
B) LDL apheresis
C) Smoking
D) High BMI
E) Keeping higher blood pressure



Answer: B

Cholesterol emboli  is a dreaded devastating complication of atherosclerosis particularly after vascular procedures. Kidney failure can be permanent. Various approaches have been tried including steroids, statin and anticoagulation. Some data suggests that LDL aphresis may be helpful in such situations. Actually, a combination therapy of LDL aphresis, low-dose steroid, and an Angiotensin II receptor blockers (ARBs) has been suggested as an effective treatment.

HD has no role in cholesterol emboli unless kidney failure happens (choice A)

Smoking, high BMI and hypertension are actually risk factors for cholesterol emobli (Choices C, D and E).

#nephrology
#surgicalcriticalcare
#vascular



References:

1. Hasegawa M, Sugiyama S. Apheresis in the treatment of cholesterol embolic disease. Ther Apher Dial 2003; 7:435. 

2. Tamura K, Umemura M, Yano H, et al. Acute renal failure due to cholesterol crystal embolism treated with LDL apheresis followed by corticosteroid and candesartan. Clin Exp Nephrol 2003; 7:67.

3. Muso E, Mune M, Fujii Y, et al. Significantly rapid relief from steroid-resistant nephrotic syndrome by LDL apheresis compared with steroid monotherapy. Nephron 2001; 89:408.

Wednesday, May 16, 2018

ionized calcium in AKI patients

Q: What are the two reasons to prefer serum ionized calcium measurement over total serum calcium level in Acute Kidney Injury (AKI) patients?



Answer: One well-known reason to measure serum ionized calcium in AKI patients is the fact that the total serum calcium concentration does not accurately reflect the actual calcium level as these patients may have low serum albumin levels, and calcium is bound to albumin. 

The objective of above question is to highlight the second reason to prefer serum ionized calcium measurement over total serum calcium measurement in AKI patients. The binding of calcium to albumin is pH dependent, and the amount of free calcium may be altered by acid-base disorders or by its rapid correction.

#nephrology
#acidbase
#electrolytes

Tuesday, May 15, 2018

Enteral feed in prone positioning

Q: Which one precaution should be taken for enteral tube feeding while switching patient from prone position to supine position after dose of "proning" during ARDS treatment?


Answer:  One inherent risk of prone positioning during refractory ARDS treatment is vomiting as well as increased residual gastric volumes. It would be appropriate to temporarily hold the tube feed, emptied the stomach emptied prior to switching back to the supine position.

#nutrition
#ventilators
#ARDS



References:


1. Reignier J, Thenoz-Jost N, Fiancette M, et al. Early enteral nutrition in mechanically ventilated patients in the prone position. Crit Care Med 2004; 32:94. 

2. Saez de la Fuente I, Saez de la Fuente J, Quintana Estelles MD, et al. Enteral Nutrition in Patients Receiving Mechanical Ventilation in a Prone Position. JPEN J Parenter Enteral Nutr 2016; 40:250.

Monday, May 14, 2018

Mimickers of Brain death

Q: All of the following can mimic brain death scenario and should be ruled out before declaring a patient brain dead except

A) Upper limb pronation extension reflex

B) Locked-in syndrome
C) Hypothermia 
D) Drug intoxication 
E) Guillain-Barré syndrome


Answer: A

Upper limb pronation extension reflex originates from the spinal cord or peripheral nerve and may occur in brain death. All other situations (choices B, C, D, and E) may mimic brain death where a patient is actually not dead.


#braindeath
#endoflifecare


References:

1. Saposnik G, Bueri JA, Mauriño J, et al. Spontaneous and reflex movements in brain death. Neurology 2000; 54:221. 


2. Beckmann YY, Ciftçi Y, Seçil Y, Eren S. Fasciculations in brain death. Crit Care Med 2010; 38:2377.


3. Patterson JR, Grabois M. Locked-in syndrome: a review of 139 cases. Stroke 1986; 17:758. 

4. Danzl DF, Pozos RS. Accidental hypothermia. N Engl J Med 1994; 331:1756. 

5. Stojkovic T, Verdin M, Hurtevent JF, et al. Guillain-Barré syndrome resembling brainstem death in a patient with brain injury. J Neurol 2001; 248:430.

Sunday, May 13, 2018

"Levine sign" in cardiology

Q: What is  "Levine sign" in cardiology?

Answer: When a patient describes his or her chest pain during cardiac ischemia with a clenched fist in the center of the chest, it is known as "Levine sign". Patient classically used right arm to make a fist as the referred pain associated with ischemia mostly radiates to the left arm. Similarly, it has an Argentinian version (as described by an Argentinian cardiologist) named as "Cossio's Sign" where a patient uses his entire palm over the chest.

#cardiology


Reference:

1. Edmondstone WM (1995). "Cardiac chest pain: does body language help the diagnosis?". BMJ. 311 (7021): 1660–1.

Saturday, May 12, 2018

ACE-I / ARBs and Erythropoiesis

Q: Angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin II receptor blockers (ARBs) - (select one)

A) enhance erythropoiesis
B) inhibit erythropoiesis 


Answer: B

For reasons not fully understood ACE-I and ARBs inhibit erythropoiesis in patients and may increase the erythropoietin requirements during maintenance dialysis. Taking advantage of this side effect these drugs can be utilized to treat posttransplant erythrocytosis (PTE) which may occur in up to 15 percent of post-kidney transplant patients with hemoglobin concentration >17 g/dL (hematocrit >51 percent). It usually manifests within first few months of transplantation. 

#transplantation
#pharmacology
#hematology


References:

1. Vlahakos DV, Marathias KP, Agroyannis B, Madias NE. Posttransplant erythrocytosis. Kidney Int 2003; 63:1187.

2. Perazella M, McPhedran P, Kliger A, et al. Enalapril treatment of posttransplant erythrocytosis: efficacy independent of circulating erythropoietin levels. Am J Kidney Dis 1995; 26:495.

3.  Yildiz A, Cine N, Akkaya V, et al. Comparison of the effects of enalapril and losartan on posttransplantation erythrocytosis in renal transplant recipients: prospective randomized study. Transplantation 2001; 72:542. 

4. Gossmann J, Thürmann P, Bachmann T, et al. Mechanism of angiotensin converting enzyme inhibitor-related anemia in renal transplant recipients. Kidney Int 1996; 50:973. 

Friday, May 11, 2018

Burton's Line

Q: “Burton's line” named after the physician who first described it, is a thin bluish purple line at the tooth and gum interface. This line is a clinical sign of which metal toxicity?


Answer: Lead toxicity

Although 'Burton's line', also known as 'lead line' is not a hallmark sign of lead toxicity but in view of pertaining history and other symptoms like colicky abdominal pain, it calls for Blood Lead Level (BLL) check up. Also, presence of basophilic stippling on blood smear can be an associated finding. Burton’s line occurs due to the interaction of the circulating lead and the sulphur ions released by oral micro flora. This causes the deposition of lead sulphide at the tooth gum interface.

See related article with picture here

Link: http://bilagi.org/blog/2016/08/07/lead-line-on-gumsburton-line/




Thursday, May 10, 2018

diagnosis in neutropenic enterocolitis

 Q: Which of the following is the gold standard for diagnosis in neutropenic enterocolitis? (select one)

A) Computed tomography (CT) of the abdomen

B) Plain films of the abdomen (KUB)
C) Blood and stool cultures with C. difficile toxin assays 
D) Barium enema
E) Colonoscopy


Answer:  A

The objective of above question is to highlight the dangers of barium enema and coloscopy in the neutropenic enterocolitis, popularly known as 'typhlitis'. Barium enema and colonoscopy can cause perforations. Also with thrombocytopenia in the setting of post-chemotherapy, colonoscopy may induce bleeding.

Plain films may be helpful to see fluid level and are noninvasive. Similarly, cultures may guide the choice of antibiotics.


References: 

1. Wade DS, Nava HR, Douglass HO Jr. Neutropenic enterocolitis. Clinical diagnosis and treatment. Cancer 1992; 69:17. 

2.  Kirkpatrick ID, Greenberg HM. Gastrointestinal complications in the neutropenic patient: characterization and differentiation with abdominal CT. Radiology 2003; 226:668.

Wednesday, May 9, 2018

Hemodialysis in Beta Blocker overdose

Q: Hemodialysis is recommended in which of the refractory case of which of the Beta Blockers?

A) Metoprolol
B) Propranolol 
C) Timolol 
D) Atenolol
E) All of the above


Answer: D

Beta-blocker overdose is tricky in the sense that hemodialysis will work only with hydrophilic and minimally protein-bound beta blockers. These include atenolol, nadolol, sotalol and acebutolol. Unfortunately, commonly used beta blockers such as metoprolol, propranolol, and timolol do not get removed by hemodialysis.

#toxicology


Reference: 

DeLima LG, Kharasch ED, Butler S. Successful pharmacologic treatment of massive atenolol overdose: sequential hemodynamics and plasma atenolol concentrations. Anesthesiology 1995; 83:204.

Tuesday, May 8, 2018

Unilateral pulmonary edema

Q: Unilateral cardiogenic pulmonary edema in acute decompensated heart failure (ADHF) is most likely due to? (select one) 

A) Pulmonary embolism (PE) 
B) Mitral regurgitation 
C) Chronic pulmonary hypertension 
D) Cirrhosis 
E) Blunt trauma to pericardium


Answer: B

Chest X-ray (CXR) remained a mainstay of diagnostic workup in acute decompensated heart failure. Classic teaching of having  "butterfly" appearance from bilateral interstitial markings is still very valid but it needs to be known that about 20% of patients in ADHF may have a normal CXR, and about 2% may have an unilateral cardiogenic pulmonary edema and the cause is mostly eccentric mitral regurgitation proved otherwise.

#Cardiology


References:

1. Attias D, Mansencal N, Auvert B, et al. Prevalence, characteristics, and outcomes of patients presenting with cardiogenic unilateral pulmonary edema. Circulation 2010; 122:1109. 

2. Wang CS, FitzGerald JM, Schulzer M, et al. Does this dyspneic patient in the emergency department have congestive heart failure? JAMA 2005; 294:1944.

Monday, May 7, 2018

Propensity score matching (PSM)

Q: What is a propensity score matching (PSM)?


Answer: Propensity score matching is a balancing score to minimize the effect of confoundings by accounting for most of the measurable covariates between the treated and untreated subjects. Propensity score can allow to design and analyze an observational study so as to mimic the characteristics of a randomized study. From a linear combination of a large observation data (a large number of covariates), a single score is obtained balancing the treatment and control groups without losing a large number of observations.  It is a powerful tool and most of the commercially available biostatistics software have an implementation to measure it.


Reference:

Austin P.C. A critical appraisal of propensity score matching in the medical literature from 1996 to 2003. Statistics in Medicine. 2008b;27:2037–2049.

Sunday, May 6, 2018

Lone hypoalbuminemia and pulmonary edema

Q: Lone hypoalbuminemia can cause pulmonary edema?

A) True
B) False


Answer: B

There are many causes of noncardiogenic pulmonary edema including ARDS, high altitude, neurogenic pulmonary edema, opioid overdose, pulmonary embolism, eclampsia, and transfusion-related acute lung injury (TRALI), but hypoalbuminemia by itself doesn't cause pulmonary edema. This is due to the fact that the pulmonary capillaries appear to have a greater baseline permeability to albumin and therefore have a higher interstitial oncotic pressure at about 18 mmHg than do peripheral capillaries. A fall in the plasma albumin concentration is associated with a parallel decline in the pulmonary interstitial oncotic pressure. The net effect is little or no change in the transcapillary oncotic pressure gradient. Although it may increase the risk in associated diseases such as CHF.



Reference:

Taylor AE. Capillary fluid filtration. Starling forces and lymph flow. Circ Res 1981; 49:557. 

Saturday, May 5, 2018

Clonidine as an effective analgesic

Q: Beside an effective anti-hypertensive, Clonidine is also an effective analgesic (select one)

A) True
B) False


Answer:  A

Clonidine and Dexmedetomidine are Alpha-2 receptor agonists which have effective analagesic effect and can be used in surgical ICUs to reduce use of narcotics and their withdrawal. Actually they have synergistic analgesic effect when used with narcotics. There is a weak evidence that using oral clonidine 150 to 200 mcg preoperatively provides perioperative hemodynamic stability and reduces the requirement of postoperative narcotic analgesics.


References: 

1. Sung CS, Lin SH, Chan KH, et al. Effect of oral clonidine premedication on perioperative hemodynamic response and postoperative analgesic requirement for patients undergoing laparoscopic cholecystectomy. Acta Anaesthesiol Sin 2000; 38:23.

2. White PF. The changing role of non-opioid analgesic techniques in the management of postoperative pain. Anesth Analg 2005; 101:S5.

3. Gold MS, Redmond DE Jr, Kleber HD. Clonidine blocks acute opiate-withdrawal symptoms. Lancet 1978; 2:599. 

4. De Kock M, Crochet B, Morimont C, Scholtes JL. Intravenous or epidural clonidine for intra- and postoperative analgesia. Anesthesiology 1993; 79:525.

Friday, May 4, 2018

reliable early sign of malignant hyperthermia

Q: Out of the followings which is the most reliable early sign of malignant hyperthermia (MH)?

A) Hypercarbia 
B) Sinus tachycardia 
C) Masseter muscle rigidity
D) Generalized muscle rigidity
E) Hyperthermia


Answer: A

Malignant hyperthermia (MH) is a hypermetabolic crisis when a MH-susceptible (MHS) patient is exposed to a volatile anesthetic or succinylcholine. Interestingly, the most reliable initial clinical sign 'heralding' the development of MH is hypercarbia. This hypercarbia is usually resistant to increasing the minute ventilation on a ventilator. It is not uncommon to see PaCO2 >65 mmHg.



Reference:

Larach MG, Gronert GA, Allen GC, et al. Clinical presentation, treatment, and complications of malignant hyperthermia in North America from 1987 to 2006. Anesth Analg 2010; 110:498.

Thursday, May 3, 2018

Cardiac mechanical circulatory support

Q: Cardiac mechanical circulatory support/devices can be used as 

A) Bridge to transplantation 
B) Bridge to decision 
C) Destination therapy 
D) Bridge to recovery
E) All of the above


Answer: E

Objective of above question is to bring in light the rapidly expanded role of cardiac devices in the field of cardiology. In contrast to previous practice, circulatory assist devices are in use very frequently even as a permanent destination therapy or as a bridge till team can reach on decision for further treatment plan (vs palliative care). These include right or left ventricular assist devices (RVAD or LVAD), biventricular device (BiVAD), total artificial heart (TAH), ProtekDuo cannula and others.




Reference: 


McMurray JJ, Adamopoulos S, Anker SD, et al. ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure 2012: The Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association (HFA) of the ESC. Eur Heart J 2012; 33:1787.

Wednesday, May 2, 2018

Respiratory depression in antipsychotics

Q: Out of the following second generation (atypical) antipsychotics, which one is most prone to cause respiratory depression?

A) Clozapine 
B) Risperidone 
C) Olanzapine 
D) Quetiapine
E) Ziprasidone 


Answer:  D

Quetiapine is the most widely used second-generation antipsychotic in ICUs in the United States. Out of all, an excess of quetiapine is most likely to cause respiratory depression as well as hypotension.



Reference: 


Ngo A, Ciranni M, Olson KR. Acute quetiapine overdose in adults: a 5-year retrospective case series. Ann Emerg Med 2008; 52:541.

Tuesday, May 1, 2018

Heliox and vocal cord dysfunction

Q: Heliox may make vocal cord dysfunction worse (select one)

A) True
B) False


Answer: B

Use of Heliox is well known in compromised large airways, but use of Heliox can also be very beneficial in vocal cord dysfunction. Efficacy is again due to increased tendency to laminar flow and reduced resistance in turbulent flow. 




References: 

Weir M. Vocal cord dysfunction mimics asthma and may respond to heliox. Clin Pediatr (Phila). 2002;41(1):37–41. 

Berkenbosch JW, Grueber RE, Graff GR, Tobias JD. Patterns of heliumoxygen (heliox) usage in the critical care environment. J Intensive Care Med. 2004;19(6):335–344.

Monday, April 30, 2018

Auto-PEEP and Physical Exam

Q: Physical examination can exclude but cannot confirm auto-PEEP?

A) True
B) False


Answer: False

Physical exam of the chest in patients who are on mechanical ventilation can confirm auto-PEEP but cannot exclude auto-PEEP. Careful auscultation, as well as palpation, may demonstrate continued expiratory airflow from the previous breath when the next breath is triggered by a mechanical ventilator.


Reference: 

Kress JP, O'Connor MF, Schmidt GA. Clinical examination reliably detects intrinsic positive end-expiratory pressure in critically ill, mechanically ventilated patients. Am J Respir Crit Care Med 1999; 159:290.

Sunday, April 29, 2018

Lagging of pulse-ox

Q: Pulse-oximetry reading (finger probe) lags behind the central arterial circulation?

A) True
B) False


Answer: True (A)

Although sound very simple and obvious but this is a critical point in intensive care unit's patients where other clinical signs of deterioration precede before desaturation. This lagging of pulse-ox desaturation may put an unexperienced house-staff under false sense of comfort and golden moment of intervention may get lost.



References:

1. Weingart SD, Levitan RM. Preoxygenation and prevention of desaturation during emergency airway management. Ann Emerg Med 2012; 59:165.

2. Ding ZN, Shibata K, Yamamoto K, et al. Decreased circulation time in the upper limb reduces the lag time of the finger pulse oximeter response. Can J Anaesth 1992; 39:87.

Saturday, April 28, 2018

marker of mortality in heart-lung transplantation

Q: Which of the following marker is a good predictor of mortality in patients with severe pulmonary hypertension who undergoes heart-lung transplant?

A) Thrombocytopenia
B) Hyperbilirubinemia
C) Hypercalcium 
D) High LDH  level
E) baseline PO2 on room air prior to transplant


Answer: B

End stage pulmonary hypertension  results in hyperbilirubinemia due to chronic passive hepatic congestion. Persistent hyperbilirubinemia has been found to be a good marker of postoperative mortality in heart-lung transplant recipients due to end stage pulmonary hypertension.



#transplantation


Reference:

Reichenberger F, Pepke-Zaba J, McNeil K, et al. Atrial septostomy in the treatment of severe pulmonary arterial hypertension. Thorax 2003; 58:797.

Friday, April 27, 2018

Hemiparesis or reflex asymmetry which alternates from side to side

Q: Hemiparesis or reflex asymmetry which alternates from side to side is usually the characteristic of which encephalopathy? 

A) Uremic encephalopathy
B) Wernicke's encephalopathy
C) Hepatic encephalopathy
D) post stroke encephalopathy
E) Post-transplant encephalopathy


Answer: A

Although not commonly present, hemiparesis or reflex asymmetry may occur in uremic encephalopathy. It quickly gets reversed with hemodialysis. If occurs, it tends to alternate from side to side.


#Nephrology
#Neurology


Reference:

Chen R, Young GB. Metabolic Encephalopathies. In: Baillere's Clinical Neurology, Bolton CF, Young GB (Eds), Balliere Tindall, London p.577.

Thursday, April 26, 2018

Silicone embolism syndrome

Q: Silicone embolism syndrome is a clinical diagnosis?

A) True
B) False


Answer: A (True)

Silicone embolism syndrome which may occur after silicone injection for cosmetic and/or therapeutic therapy. It is very much like fat embolism syndrome and has the clinical triad of
  • hypoxemia, 
  • fever, and 
  • a petechial rash

The most devastating manifestation can be diffuse alveolar damage.

Treatment is supportive.


References:

1. Chung KY, Kim SH, Kwon IH, et al. Clinicopathologic review of pulmonary silicone embolism with special emphasis on the resultant histologic diversity in the lung--a review of five cases. Yonsei Med J 2002; 43:152. 

2. Schmid A, Tzur A, Leshko L, Krieger BP. Silicone embolism syndrome: a case report, review of the literature, and comparison with fat embolism syndrome. Chest 2005; 127:2276.

Wednesday, April 25, 2018

Risk correction in Fat Embolism Syndrome

Q: Early operative correction of fractures increases the chance of fat embolism syndrome (FES)?

A) True
B) False


Answer: B (False)

Few measures which decrease the chances of FES after long bone trauma include early immobilization of fracture, early operative correction, intraosseous pressure limitation and arguably steroids.




References:

1. Riska EB, Myllynen P. Fat embolism in patients with multiple injuries. J Trauma 1982; 22:891. 


2. Kröpfl A, Davies J, Berger U, et al. Intramedullary pressure and bone marrow fat extravasation in reamed and unreamed femoral nailing. J Orthop Res 1999; 17:261. 

3. Sen RK, Tripathy SK, Krishnan V. Role of corticosteroid as a prophylactic measure in fat embolism syndrome: a literature review. Musculoskelet Surg 2012; 96:1.