Saturday, April 20, 2019

Delta P on ECMO

Q: What does Delta P on ECMO's every day monitoring signifies?



Answer: The difference between the pressures on pre and post membrane outlets provides the transmembrane pressure gradient. An increase in the trans-membrane pressure gradient indicates clot formation within the oxygenator. The trans-membrane pressure gradient should stay less than 50 mm Hg. If high, it requires proper anti-coagulation or may be the replacement of oxygenator.


#ECMO



References:  


1. Adult Extra Corporeal membrane Oxygenation (ECMO); Policy & Guideline. RPAH 2010 

2. Extra Corporeal Membrane Oxygenation (ECMO) in the Intensive Care Unit. St Vincent’s Hospital Sydney ICU 2010 3. Marasco, S.F., Lukas, G., McDonald, M., McMillan, J., & Ihle, B. (2008).

3.Review of ECMO (Extra Corporeal Membrane Oxygenation) support in critically ill adult patients. Heart, Lung and Circulation, 17S: S41-S47.

Friday, April 19, 2019

HBV in pregnancy

Q: Acute Hepatitis B Virus (HBV) has the highest rate of transmission? (select one)

A) early in the pregnancy
B) near the time of delivery


Answer: B

This piece of maternal hepatology is extremely important to know as an active intervention is required if HBV occurs near the time of delivery.

Transmission to the fetus may be as low as 10 percent in the early part of the pregnancy but may go up to 60 percent at the time of delivery. Hepatitis panel should be followed closely. If hepatitis B surface antigen (HBsAg) stays positive or has detectable serum HBV DNA near the delivery, baby should receive hepatitis B immune globulin and the 1st dose of the hepatitis B vaccine within 12 hours of birth. Ideally, a hepatologist should be consulted.

#hepatology
#OB-Gyn


References:

1. Sookoian S. Liver disease during pregnancy: acute viral hepatitis. Ann Hepatol 2006; 5:231. 

 2. Jonas MM. Hepatitis B and pregnancy: an underestimated issue. Liver Int 2009; 29 Suppl 1:133.

Thursday, April 18, 2019

PG toxicity

Q: Continuous intravenous (IV) lorazepam is frequently used in ICU. Propylene glycol (PG) is the carrier to administer IV lorazepam drip. Prolong use of IV lorazepam may cause propylene glycol toxicity. Which one test could predict and correlate directly with PG toxicity?


Answer:  Osmolal gap 

 Propylene glycol toxicity may occur with prolong administration of lorazepam or diazepam. It can cause significant skin and soft tissue necrosis in case of extravasation, arrhythmia, hemodynamic instability, lactic acidosis, seizure, coma, and eventually multi-system organ failure (MSOF). Propylene glycol causes hyperosmolarity and an anion gap metabolic acidosis. In case of any suspicion, osmolal gap correlates with PG concentrations and can be a reliable surrogate marker of PG toxicity. Treatment is to discontinue the infusion and, if life-threatening, emergent hemodialysis should be instituted. 

#toxicology


References:

1. Wilson KC, Reardon C, Theodore AC, Farber HW. Propylene glycol toxicity: a severe iatrogenic illness in ICU patients receiving IV benzodiazepines: a case series and prospective, observational pilot study. Chest 2005; 128:1674. 

2. Barnes BJ, Gerst C, Smith JR, et al. Osmol gap as a surrogate marker for serum propylene glycol concentrations in patients receiving lorazepam for sedation. Pharmacotherapy 2006; 26:23. 

Wednesday, April 17, 2019

AP in pregnancy

Q: 24 year female at 34 weeks of pregnancy is admitted to ICU with exacerbation of asthma which is getting better. Routine labs showed three times higher than normal value of Serum alkaline phosphatase (AP). All other lab values are in normal range. What should be your next step?

A) STAT ultrasound of the liver
B) Emergent delivery of the baby
C) Check for HELLP syndrome
D) No intervention at this time
E) Check Hepatitis panel


Answer: D

Pregnancy may affect liver function test, particularly serum alkaline phosphatase. Total serum AP goes up to 3-4 times higher than normal, particularly in the third trimester. This is due to placental alkaline phosphatase. The best approach is to look at serum gamma-glutamyl transpeptidase (GGTP) level, which usually gets lower in pregnancy. This may help to confirm placental source of AP. In the absence of no other findings, there is no reason to go behind a million dollar workup.

Ultrasound of liver can be considered but there is no need for STAT order (choice A)

Patient's clinical situation is improving. Until and unless there is no harm anticipated to baby, there is no need to rush for delivery (choice B)

With normal platelet count and other LFTs in normal range, it is unlikely to be HELLP syndrome (choice C).

With no abnormality in AST, ALT, and bilirubin, hepatitis is very unlikely (choice E)


#Ob-gyn
#hepatology


Reference:

Bacq Y, Zarka O, Bréchot JF, et al. Liver function tests in normal pregnancy: a prospective study of 103 pregnant women and 103 matched controls. Hepatology 1996; 23:1030.

Tuesday, April 16, 2019

Secondary PPH

Q: Secondary postpartum hemorrhage (PPH) is defined as any significant uterine bleeding occurring after?

A) 24 hours postpartum
B) 48 hours postpartum
C) 72 hours postpartum
D) one week postpartum
E) it is not defined by time


Answer: A

Primary and secondary PPH is defined by the cutoff of a time period and is also limited by a time period. i.e., Secondary PPH is generally defined as any significant uterine bleeding between 24 hours and 12 weeks postpartum. This cutoff is set as management may become different for primary and secondary PPH.

#ob-gyn
#surgicalcriticalcare


References:

1. Committee on Practice Bulletins-Obstetrics. Practice Bulletin No. 183: Postpartum Hemorrhage. Obstet Gynecol 2017; 130:e168. 

2. Dossou M, Debost-Legrand A, Déchelotte P, et al. Severe secondary postpartum hemorrhage: a historical cohort. Birth 2015; 42:149.

Monday, April 15, 2019

Left Main Equivalent Disease

Q: What is Left main equivalent disease? 


Answer:  Although left main coronary artery disease (LMCAD) is a well-known disease, and a subject of frequent discussions, unfortunately, less attention gets paid to Left main equivalent disease, which is equally dreaded in morbidity and mortality.  Left main equivalent disease is defined as a combination of severe i.e. > 70 % stenosis of proximal left anterior descending (LAD) coronary artery and proximal left circumflex disease. It signifies a poor prognosis. Coronary artery bypass graft surgery (CABG) is associated with improved survival.

#cardiology
#surgicalcriticalcare


References:

1. Chaitman BR, Davis K, Fisher LD, et al. A life table and Cox regression analysis of patients with combined proximal left anterior descending and proximal left circumflex coronary artery disease: non-left main equivalent lesions (CASS). Circulation 1983; 68:1163. 

2. Caracciolo EA, Davis KB, Sopko G, et al. Comparison of surgical and medical group survival in patients with left main equivalent coronary artery disease. Long-term CASS experience. Circulation 1995; 91:2335.

Sunday, April 14, 2019

IVF in acute pancreatitis

Q: Which of the following intravenous fluid (IVF) preferred in acute pancreatitis?

A) Normal Saline (NS)
B) Lactate Ringer's (LR)


Answer: B

The three pillars of management of acute pancreatitis are
  • fluid resuscitation 
  • pain control
  • nutritional support 
IVF take precedence over everything as it has clearly shown that early and proper (considering renal failure and congestive heart failure) IVF resuscitation decreases analgesic requirement, increases enteral tolerance and decreases morbidity and mortality.

Although evidence is not very strong it favors LR as a preferred agent if there is no renal insuff., hypercalcemia or hyperkalemia. LR has shown to lower mean C-reactive protein (CRP) level and reduction in systemic inflammatory response syndrome (SIRS).

#gastroenterelogy
#resuscitation
#hemodynamic


References:

1. Working Group IAP/APA Acute Pancreatitis Guidelines. IAP/APA evidence-based guidelines for the management of acute pancreatitis. Pancreatology 2013; 13:e1. 

 2. Wu BU, Hwang JQ, Gardner TH, et al. Lactated Ringer's solution reduces systemic inflammation compared with saline in patients with acute pancreatitis. Clin Gastroenterol Hepatol 2011; 9:710. 

3. Trikudanathan G, Navaneethan U, Vege SS. Current controversies in fluid resuscitation in acute pancreatitis: a systematic review. Pancreas 2012; 41:827. 

4. Gardner TB, Vege SS, Chari ST, et al. Faster rate of initial fluid resuscitation in severe acute pancreatitis diminishes in-hospital mortality. Pancreatology 2009; 9:770.

Saturday, April 13, 2019

IV contrast in sickle cell

Q: Intravenous iodinated contrast can induce sickle crisis in patients with sickle cell disease? (select one)

A) True
B) False


Answer:  B

It has been speculated in the past that IV iodinated contrast is not safe for sickle cell patients but this fear is proved to be unfounded. This was postulated that IV iodinated contrast contrast because of their high osmolality may cause osmotic shrinkage of red blood cells, and may precipitate a sickle cell crisis. Studies have shown that clinically this is not significant and risk is equivalent to general population if renal function is normal.

#radiology
#allergy


References:

1. Morcos SK. Review article: Acute serious and fatal reactions to contrast media: our current understanding. Br J Radiol 2005; 78:686. 

2. Kimberly L. et.al. Safety of Iodinated Intravenous Contrast Medium Administration in Sickle Cell Disease - The American Journal of Medicine Volume 125, Issue 1, January 2012, Pages 100.e11-100.e16

Friday, April 12, 2019

HBO any myopia

Q: Myopia from hyperbaric oxygen (HBO) is? (select one) 

 A) Reversible 
B) Irreversible


Answer: A

Modality of hyperbaric oxygen is frequently used as an adjuvant therapy in different variety of patients and it is not uncommon for an ICU physician to encounter it. But it comes with it's  own price. Some of the common complications are middle ear barotrauma, sinus barotrauma, myopia, pulmonary barotrauma, seizure and decompression sickness. 


 Most of these side effects are reversible including myopia.


#hyberbaric
#ophthalmology 


Reference:


Camporesi EM, Bosco G. Mechanisms of action of hyperbaric oxygen therapy. Undersea Hyperb Med 2014; 41:247.

Thursday, April 11, 2019

citrate

Q: During continuous renal replacement therapy (CRRT) what's the best way to assesses that the excessive citrate is given and regional citrate anticoagulation (RCA) may need to be stopped?


Answer: A ratio of total calcium to ionized calcium >2.5

Other ways to suspect excessive citrate during CRRT were worsening metabolic acidosis, increasing anion gap, decreasing ionized calcium or higher requirement of calcium infusion rates.


#nephrology



References:


1. Meier-Kriesche HU, Gitomer J, Finkel K, DuBose T. Increased total to ionized calcium ratio during continuous venovenous hemodialysis with regional citrate anticoagulation. Crit Care Med 2001; 29:748. 


2. Bakker AJ, Boerma EC, Keidel H, et al. Detection of citrate overdose in critically ill patients on citrate-anticoagulated venovenous haemofiltration: use of ionised and total/ionised calcium. Clin Chem Lab Med 2006; 44:962.

Wednesday, April 10, 2019

vasoreactive test in PH

Q: All of the following can be used for vasoreactivity test in pulmonary hypertension except? 

 A) inhaled nitric oxide 
B) epoprostenol 
C) adenosine 
D) inhaled iloprost 
 E) sildenafil


Answer: E

Many times vasoreactive test in pulmonary hypertension is carried out in ICU setting as it requires close hemodynamic monitoring and right heart catheterization. Vasoreactivity test helps in determining the right agent for treatment. Drugs commonly used for vasoreactivity testing include inhaled nitric oxide, epoprostenol, adenosine, and inhaled iloprost. Sildenafil is not appropriate for this purpose.

#pulmonary
#procedure


Reference:

Badesch DB, Abman SH, Ahearn GS, et al. Medical therapy for pulmonary arterial hypertension: ACCP evidence-based clinical practice guidelines. Chest 2004; 126:35S.

Tuesday, April 9, 2019

Procalcitonin in VAP

Q: Procalcitonin has it's utility in Ventilator-Associated Pneumonia (VAP) for?  (select one)

A) Initiation of antibiotics 
B) Discontinuation of antibiotics


Answer: 

Unlike the utility of procalcitonin in making a decision for antibiotics initiation in suspected community-acquired pneumonia (CAP), it has practically no role in the initiation of antibiotics in VAP.1 But it certainly helps in determining when to stop antibiotics 2, as well as to act as a prognostic marker. 3, 4

#ventilators
#pulmonary
#infectiousdiseases


References:

1. Luyt CE, Combes A, Reynaud C, et al. Usefulness of procalcitonin for the diagnosis of ventilator-associated pneumonia. Intensive Care Med 2008; 34:1434.


2. Stolz D, Smyrnios N, Eggimann P, et al. Procalcitonin for reduced antibiotic exposure in ventilator-associated pneumonia: a randomised study. Eur Respir J 2009; 34:1364.

3. Luyt CE, Guérin V, Combes A, et al. Procalcitonin kinetics as a prognostic marker of ventilator-associated pneumonia. Am J Respir Crit Care Med 2005; 171:48.

4. Hillas G, Vassilakopoulos T, Plantza P, et al. C-reactive protein and procalcitonin as predictors of survival and septic shock in ventilator-associated pneumonia. Eur Respir J 2010; 35:805.

Monday, April 8, 2019

tPA and clot location

Q: During reperfusion therapy for acute ischemic stroke (CVA) which clots are more resistant to thrombolysis? (select one) 

 A)  proximal in the cerebrovascular arterial tree 
 B) distal in the cerebrovascular arterial tree


Answer: 

In acute CVA proximal sites of occlusion in the cerebrovascular arterial tree are more resistant to thrombolysis i.e. a clot in an internal carotid artery (ICA) is expected to be more resistant than middle cerebral artery (MCA). This is due to the fact that clots more proximal in CV arterial-tree tend to be bigger in size. Moreover, they may be promoting adjacent thrombosis, resulting in a very long thrombus. Another contributing factor is the relative lack of fibrin in large vessels in situ thromboses in comparison to cardiac origin fibrin-rich embolic thromboses.



#neurology

#cardiology


References: 


1.  Linfante I, Llinas RH, Selim M, et al. Clinical and vascular outcome in internal carotid artery versus middle cerebral artery occlusions after intravenous tissue plasminogen activator. Stroke 2002; 33:2066. 

2. Saqqur M, Uchino K, Demchuk AM, et al. Site of arterial occlusion identified by transcranial Doppler predicts the response to intravenous thrombolysis for stroke. Stroke 2007; 38:948. 

3. Molina CA, Montaner J, Arenillas JF, et al. Differential pattern of tissue plasminogen activator-induced proximal middle cerebral artery recanalization among stroke subtypes. Stroke 2004; 35:486.

Sunday, April 7, 2019

pleural N-terminal pro-BNP in CHF

Q; What is the utility of measuring pleural N-terminal pro-BNP?


Answer: Excessive diuresis in congestive heart failure (CHF) may make pleural effusion looks exudative. Pleural fluid NT-proBNP has a high degree of correlation in CHF and may have a utility in such situations. 5

#pulmonary
#cardiology



References:

1. Porcel JM. Utilization of B-type natriuretic peptide and NT-proBNP in the diagnosis of pleural effusions due to heart failure. Curr Opin Pulm Med 2011; 17:215. 

2. Kolditz M, Halank M, Schiemanck CS, et al. High diagnostic accuracy of NT-proBNP for cardiac origin of pleural effusions. Eur Respir J 2006; 28:144. 

3. Tomcsányi J, Nagy E, Somlói M, et al. NT-brain natriuretic peptide levels in pleural fluid distinguish between pleural transudates and exudates. Eur J Heart Fail 2004; 6:753. 

4. Porcel JM, Martínez-Alonso M, Cao G, et al. Biomarkers of heart failure in pleural fluid. Chest 2009; 136:671. 

5. Porcel JM, Chorda J, Cao G, et al. Comparing serum and pleural fluid pro-brain natriuretic peptide (NT-proBNP) levels with pleural-to-serum albumin gradient for the identification of cardiac effusions misclassified by Light's criteria. Respirology 2007; 12:654. 


Saturday, April 6, 2019

ABCDE of trauma

Q: Describe the "ABCDE" bundle in the primary survey of a trauma patient?


Answer: For the ease of the care of trauma patients, a simple mnemonic is developed for the primary assessment of trauma patients:
  • Airway - includes cervical spine stabilization 
  • Breathing - equivalent to adequate oxygenation 
  • Circulation - includes bleeding control with goal to maintain adequate end-organ perfusion
  • Disability assessment - includes basic neurologic evaluation 
  • Exposure - it also suggests undressing the patients, searching everywhere for possible injury, and preventing hypothermia

#trauma


Reference:

American College of Surgeons Committee on Trauma. Advanced Trauma Life Support (ATLS) Student Course Manual, 9th ed, American College of Surgeons, Chicago 2012.

Friday, April 5, 2019

Glucose level in malaria

Q: Which of the following is the sign of poor prognosis in severe malaria? (select one)

A) Hyperglycemia
B) Hypoglycemia


Answer: B

Hypoglycemia is not uncommon in malaria and may be an indicator of poor outcome. It occurs due to  decrease hepatic gluconeogenesis, depletion of hepatic glycogen stores, and increase consumption of glucose. Another very interesting cause of hypoglycemia in severe malaria is Quinine-induced hyperinsulinemia.


#pharmacology
#infectiousdiseases



Reference;

Gilbert N Ogetii, Samuel Akech, Julie Jemutai, Mwanamvua Boga, Esther Kivaya, Greg Fegan and Kathryn Maitland -  Hypoglycaemia in severe malaria, clinical associations and relationship to quinine dosage BMC Infectious Diseases 2010 10:334

Thursday, April 4, 2019

NMB in ARDS

Q: Which of the following has shown favorable outcome towards mortality in Acute Respiratory Distress Syndrome (ARDS)?

A) cisatracurium 
B) vecuronium
C) succinylcholine
D) rocuronium 
E) Use of no Neuro-Muscular Blockade (NMB)



 Answer: A

NMB are not very desirable for use in ICUs but in some situations they become life savers like severe ARDS. Interestingly, they have shown some favorable tendency in decreasing mortality in these patients.

In 2010 trial of 340 patients, group treated with cisatracurium had more ventilator-free days in first 90 days, less barotrauman but more importantly no difference in the ICU-acquired neuromuscular weakness. Another meta-analysis of five trials also reported improved mortality.


#pulmonary
#ARDS
#pharmacology


References:

Papazian L, Forel JM, Gacouin A, et al. Neuromuscular blockers in early acute respiratory distress syndrome. N Engl J Med 2010; 363:1107. 

Tao W, Yang LQ, Gao J, Shao J. Neuromuscular blocking agents for adult patients with acute respiratory distress syndrome: A meta-analysis of randomized controlled trials. J Trauma Acute Care Surg 2018; 85:1102.

Wednesday, April 3, 2019

TCA overdose

Q: Tricyclic antidepressant (TCAs) toxicity can cause? (select one) 

A) cholinergic effects 
B) anticholinergic effects 


 Answer:

 TCAs have anticholinergic effects and so the poisoning can cause hyperthermia, flushing, mydriasis that responds poorly to light, delirium, intestinal ileus, and urinary retention.



#toxicology



References:


Lynch R. Tricyclic antidepressant overdose. Emerg Med J 2002; 19:596.


Glauser J. Tricyclic antidepressant poisoning. Cleve Clin J Med 2000; 67:704.

Tuesday, April 2, 2019

Nutrition in ICU

Q: Which of the following is the preferred source of energy in critically ill patients? 

A) carbohydrates 
 B) fat (lipid) 
C) protein 
D) normal saline (0.9 NS) 
E) minerals 



 Answer: A

Lipid mobilization is impaired in critically ill patients and carbohydrates are the preferred source of energy during this time. Although the prescribed nutrition should be balanced and protein should be added to avoid negative nitrogen balance, as well as to utilize it as a substrate for gluconeogenesis.


#nutrition



Reference:



Nordenström J, Carpentier YA, Askanazi J, et al. Free fatty acid mobilization and oxidation during total parenteral nutrition in trauma and infection. Ann Surg 1983; 198:725. 


Plank LD, Connolly AB, Hill GL. Sequential changes in the metabolic response in severely septic patients during the first 23 days after the onset of peritonitis. Ann Surg 1998; 228:146.

Monday, April 1, 2019

ETT bending

Q: During intubation, an endotracheal tube (ETT) should be bent no more than?

A) 20 degrees
B) 35 degrees
C) 45 degrees
D) 60 degrees
E) 90 degrees ("hockey stick" conformation)


Answer: B

This is a common practice of some senior residents to teach junior residents to put ETT at "hockey stick" conformation if difficult intubation is anticipated. This should be done only and only in very experienced hands. Ideally, ETT should never be bent > 35 degrees. Beyond that, more acute angles may cause the ETT to get stuck on the anterior trachea, prevent advancement and injured trachea.


#procedures



Reference:

Levitan RM, Pisaturo JT, Kinkle WC, et al. Stylet bend angles and tracheal tube passage using a straight-to-cuff shape. Acad Emerg Med 2006; 13:1255.

Sunday, March 31, 2019

Heart transplant in PPCM

Q: Patients who develop Peri-Partum Cardiomyopathy (PPCM) and receive heart transplant, have? (select one)

A) Better outcome
B) Worse outcome


Answer: B

Unfortunately, patients with PPCM do not fare well in comparison to other groups of cardiomyopathy. Data showed them to have worse long-term survival. They have a higher rate of rejection, poorer graft survival, and a higher need for retransplantation. Interestingly younger patients do worse. Some of the postulated reasons are higher allosensitization and higher pretransplant acuity.


#transplantation

#cardiology
#OB-Gyn



Reference:



Rasmusson K, Brunisholz K, Budge D, et al. Peripartum cardiomyopathy: post-transplant outcomes from the United Network for Organ Sharing Database. J Heart Lung Transplant 2012; 31:180.

Saturday, March 30, 2019

ETOH ketoacidosis

Q: All of the following are the features of acute alcohol (ETOH) ketoacidosis except? 

A) history of chronic alcohol abuse
B) malnutrition
C) coma
D) nausea and vomiting
E) abdominal pain 


Answer:   C

In comparison to patients with diabetic ketoacidosis, particularly patients with nonketotic hyperosmolar hyperglycemia, patients with alcoholic ketoacidosis are usually more alert and lucid. In former conditions, there is a huge osmotic diuresis resulting in rising of effective plasma osmolality. This osmotic diuresis is not a feature of alcoholic ketoacidosis, preventing these patients from the neurologic manifestations of a marked rise in the effective plasma osmolality.

#toxicology
#acid-base
#acidosis



References:

1. Wrenn KD, Slovis CM, Minion GE, Rutkowski R. The syndrome of alcoholic ketoacidosis. Am J Med 1991; 91:119.

2.  Palmer JP. Alcoholic ketoacidosis: clinical and laboratory presentation, pathophysiology and treatment. Clin Endocrinol Metab 1983; 12:381.

3. Fulop M, Ben-Ezra J, Bock J. Alcoholic ketosis. Alcohol Clin Exp Res 1986; 10:610.

Friday, March 29, 2019

Fe supplement in IBD

Q: For all of the following reasons intravenous (IV) Iron (Fe) is a preferred route of administration in Inflammatory bowel disease (IBD) except

 A) Oral Fe is associated with increased disease activity 
B) Oral Fe is associated with increased abdominal pain 
 C) Oral Fe is poorly absorbed  
D) IV Fe has better response in iron-restricted erythropoiesis 
 E) IV Fe causes better termination of gut's microbial diversity


Answer: E


Iron deficiency and iron deficiency anemia is a part of IBD. Many patients in ICU with exacerbation of IBD may require iron treatment for severe debilitating anemia. IV Iron is preferred for various reasons. Not only the oral Fe is associated with intolerance and abdominal pain (choice B) but can also exacerbate the disease activity (choice A). Due to inflammation, it is poorly absorbed (choice C). IV Fe has shown to better overcome the iron-restricted erythropoiesis which occurs due to systemic response in IBD (choice D).


Actually, microbial diversity is required to terminate the flare-ups of IBD and IV Fe helps in preserving that (see reference#3).


#hematology

#gastroenterology


References:


1. Gomollón F, Gisbert JP. Intravenous iron in inflammatory bowel diseases. Curr Opin Gastroenterol 2013; 29:201. 


2.  Erichsen K, Ulvik RJ, Nysaeter G, et al. Oral ferrous fumarate or intravenous iron sucrose for patients with inflammatory bowel disease. Scand J Gastroenterol 2005; 40:1058. 


3. Lee T, Clavel T, Smirnov K, et al. Oral versus intravenous iron replacement therapy distinctly alters the gut microbiota and metabolome in patients with IBD. Gut 2017; 66:863.

Thursday, March 28, 2019

ABG errors

Q: Leukocytosis (High WBC) may falsely   ______________ the PaO2 in arterial blood gas (ABG)? (select one)

A) Increases
B) Decreases


Answer; B

White Blood Cells (WBCs/leukocytes) consumes oxygen and may give falsely low PaO2 in ABG. This can be countered by putting ABG sample on ice and get analyzed within 15 minutes of a draw.


#acid-base
#procedures


References:

1. Bageant, RA. Variations in arterial blood gas measurements due to sampling techniques. Respir Care 1975; 20:565. 

2. Harsten A, Berg B, Inerot S, Muth L. Importance of correct handling of samples for the results of blood gas analysis. Acta Anaesthesiol Scand 1988; 32:365. 

Wednesday, March 27, 2019

"Theo" toxicity

Q: All of the following may occur with Theophylline overdose except? 

A) cerebral vasoconstriction 
B) hyperkalemia 
C) hyperglycemia 
D) metabolic acidosis 
E) arrhythmias


Answr: B

Most of the Theophylline effect occurs via antagonism of adenosine receptors and indirect adrenergic activity (see below). This effect is used for its primary use as a bronchodilator. In the case of overdose, it causes arrhythmias (choice E), cerebral vasoconstriction (choice A) and seizure. One of the dilemmas occurs when cardiac arrhythmia results in hypotension and need for vasopressor arises. Theophylline itself increases the level of epinephrine, norepinephrine, and dopamine via catecholamine elevation. In such scenarios, vasopressin may be a relatively safer choice, though no guideline or recommendation is available for this particular clinical situation.


At higher doses, theophylline acts as a phosphodiesterase inhibitor and increases the levels of cyclic adenosine monophosphate which augments beta-adrenergic activity. It results in hypokalemia, hyperglycemia, metabolic acidosis, and beta-adrenergic mediated vasodilatation.


#toxicology

#hemodynamic


References:


1. Minton NA, Henry JA. Acute and chronic human toxicity of theophylline. Hum Exp Toxicol 1996; 15:471. 


2. Shannon M. Hypokalemia, hyperglycemia and plasma catecholamine activity after severe theophylline intoxication. J Toxicol Clin Toxicol 1994; 32:41.

Tuesday, March 26, 2019

Relative Index

Q: What is "Relative index" in cardiology biomarkers?  


Answer: Relative index is a ratio of CK-MB/total CK. The formula is 

Relative index = CK-MB/total CK x 100

Relative index helps in differentiating elevation of CK-MB between skeletal and cardiac origin. 

  • Ratio < 3 is consistent with skeletal muscle source
  • Ratio > 5 indicates cardiac source

#cardiology
#laboratory-science


Reference:

TP Singh, AK Nigam, AK Gupta, B Singh. Cardiac Biomarkers: When to Test? – Physician Perspective Journal, Indian Academy of Clinical Medicine z Vol. 12, No. 2, April-June, 2011

Monday, March 25, 2019

PEEP and PAOP

Q: If patient has a Pulmonary Artery Catheter (PAC) in place and excessive Positive End Expiratory Pressure (PEEP) is applied on ventilator, what is the rule of thumb to calculate correct Pulmonary Artery Occlusion Pressure (PAOP/wedge Pressure)? 



Answer: PEEP usually does not effect PAOP/wedge pressure clinically but once the requirement of PEEP starts going above 8-10, PAOP should be adjusted by subtracting 
  •  one-half of the PEEP level from the PAOP, if lung compliance is normal, or 
  •  one-quarter of the PEEP level if lung compliance is reduced 
For example, if a patient with acute respiratory distress syndrome (ARDS) (decreased lung compliance) with an applied PEEP of 12 cm H2O and has a wedge pressure of 14 mm Hg, the recalculated wedge pressure would be 10 mm Hg. 

#procedure

#hemodynamics
#cardiology
#pulmonary
#ventilators 



Reference:


Teboul JL, Besbes M, Andrivet P, et al. A bedside index assessing the reliability of pulmonary artery occlusion pressure measurements during mechanical ventilation with positive end-expiratory pressure. J Crit Care 1992; 7:22.

Sunday, March 24, 2019

AS and endocarditis prophylaxis

Q: All patients with critical Aortic Stenosis should receive endocarditis prophylaxis?

A) True
B) False


Answer: B

Unfortunately, very few cases of infective endocarditis (IE) can be prevented by antibiotic prophylaxis. New guidelines recommend antibiotic prophylaxis only for patients with underlying cardiac conditions associated with the highest risk. High-risk cardiac conditions are defined as prosthetic valves, congenital heart disease (CHD), history of infective endocarditis and heart transplant patients with valvular disease.

#cardiology
#infectiousdiseases


References:


1. Bonow RO, Carabello BA, Chatterjee K, et al. 2008 Focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease): endorsed by the Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. Circulation 2008; 118:e523.


2. Wilson W, Taubert KA, Gewitz M, Lockhart PB, Baddour LM, Levison M, et al. Prevention of infective endocarditis: guidelines from the American Heart Association: a guideline from the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee, Council on Cardiovascular Disease in the Young, and the Council on Clinical Cardiology, Council on Cardiovascular Surgery and Anesthesia, and the Quality of Care and Outcomes Research Interdisciplinary Working Group. Circulation. 2007 Oct 9. 116(15):1736-54.

Saturday, March 23, 2019

Post Cardiac Surgery Pleural Effusion

Q: Pleural effusion is common at which side in early post coronary artery bypass grafting (CABG) surgery? (select one)  

A) Right 
B) Left


Answer:  B

Early pleural effusions after CABG surgery are usually benign and mostly occur on left side. These are also seen commonly after a heart transplant. In contrast, cardiac valve surgeries are less intent to produce pleural effusions. If the effusion is symptomatic, large and on the right side, it may be a sign of some other underlying disease process (see interesting reference #4 below in this regard).

#pulmonary
#surgicalcriticalcare


References:

1. Vargas FS, Cukier A, Hueb W, et al. Relationship between pleural effusion and pericardial involvement after myocardial revascularization. Chest 1994; 105:1748.

2. Ulubay G, Küpeli E, Er Dedekargınoğlu B, et al. Postoperative Pleural Effusions After Orthotopic Heart Transplant: Cause, Clinical Manifestations, and Course. Exp Clin Transplant 2016; 14:125. 

3. Light RW, Rogers JT, Cheng D, Rodriguez RM. Large pleural effusions occurring after coronary artery bypass grafting. Cardiovascular Surgery Associates, PC. Ann Intern Med 1999; 130:891. 

4. Kunizawa A, Fujioka M, Mink S, Keller E. Central venous catheter-induced delayed hydrothorax via progressive erosion of central venous wall. Minerva Anestesiol 2010; 76:868. 




Friday, March 22, 2019

hung up reflexes

Q: Woltman sign, also known as "hung-up" deep tendon reflexes on clinical examination is a sign of? (select one) 

A) Hypothyroidism 
B) Hyperthyroidism 


Answer:

"hung-up" deep tendon reflexes on clinical examination are due to delayed muscle relaxation - and is a frequent finding in myopathy secondary to hypothyroidism. It is more evident in severe hypothyroidism and is considered a classic sign of this disease. 


(Reference has a video demonstration included. Click on the link)


https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2492977/



#physicalexam

#endocrine
#musculoskeletal


Reference: 

Cyriac S, d'Souza SC, Lunawat D, Shivananda P, Swaminathan M. A classic sign of hypothyroidism: a video demonstration. CMAJ. 2008;179(4):387. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2492977/

Thursday, March 21, 2019

Peliosis hepatis in chronic kidney disease

Q: Peliosis hepatis in chronic kidney disease patients get treated by kidney transplantation?  

A) True 
B) False 


 Answer:

Peliosis hepatis, first described about 70 years ago, is one dreaded disease which has many etiologies but unfortunately no specific treatment. Moreover, it goes undiagnosed without any symptom for an extended period. Although mostly limited to the liver, it may occur in other organs such as spleen or lungs. By definition, it a proliferation of the sinusoidal hepatic capillaries that results in cystic blood-filled cavities throughout the liver. It may occur due to drugs (steroids are the most common), underlying immune disorders or infections particularly with tuberculosis.


For reasons not clearly understood, in renal patients peliosis hepatis either gets acquired or gets worse after transplant. Probable etiologies are immunosuppressant drugs or development of opportunistic infections after transplantation.


#transplantation

#hepatology
#nephrology 


References:


1. ZAK FG. Peliosis hepatis. Am J Pathol 1950; 26:1. 


2. Izumi S, Nishiuchi M, Kameda Y, et al. Laparoscopic study of peliosis hepatis and nodular transformation of the liver before and after renal transplantation: natural history and aetiology in follow-up cases. J Hepatol 1994; 20:129.

 3. Cavalcanti R, Pol S, Carnot F, et al. Impact and evolution of peliosis hepatis in renal transplant recipients. Transplantation 1994; 58:315. 

4. Ahsan N, Rao KV. Hepatobiliary diseases after kidney transplantation unrelated to classic hepatitis virus. Semin Dial 2002; 15:358.

Wednesday, March 20, 2019

solitary hypoalbuminemia and non-cardiogenic edema

Q: Solitary hypoalbuminemia can cause non-cardiogenic edema? 

A) True
B) False


Answer: B

It is true that pure hypoalbuminemia causes the peripheral edema due to the lowering of the transcapillary oncotic pressure gradient, but pulmonary capillaries have a greater baseline permeability to albumin. Because of this high permeability, a fall in the plasma albumin concentration is accompanied by a parallel decline in the pulmonary interstitial oncotic pressure, and the net effect is little or no change in the transcapillary oncotic pressure gradient.

#pulmonology

#cardiology


Reference: 


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

Tuesday, March 19, 2019

CIN

Q: Which of the following has a higher risk of contrast-induced nephropathy (CIN)? (select one)

A) interventional coronary angiography
B) CT scan with intravenous (IV) contrast


Answer: A

The objective of above question is to emphasize the point that contrary to popular belief the risk of CIN from CT scan with IV contrast is relatively low even in patients with a lower degree of renal insufficiency.

Interventional coronary angiography is a way bigger risk for CIN due to its emergent nature, not allowing any time for any preventive measure, the patient is usually dehydrated and has hemodynamic instability.

#cardiology
#nephrology
#procedure


References:

1. Jurado-Román A, Hernández-Hernández F, García-Tejada J, et al. Role of hydration in contrast-induced nephropathy in patients who underwent primary percutaneous coronary intervention. Am J Cardiol 2015; 115:1174. 

2. Weisbord SD, Mor MK, Resnick AL, et al. Incidence and outcomes of contrast-induced AKI following computed tomography. Clin J Am Soc Nephrol 2008; 3:1274. 

3. McDonald RJ, McDonald JS, Carter RE, et al. Intravenous contrast material exposure is not an independent risk factor for dialysis or mortality. Radiology 2014; 273:714.

Monday, March 18, 2019

Skin fold in ICU mimicking PTX

Q: What is the most common cause of skin fold mimicking pneumothorax (PTX) in an ICU patient?

Answer:  In ICU most of the bedside chest X-rays are obtained by sliding radiographic plate (cassette) from the side under the patient's back. Skin folds should be suspected in obese patients with no reason to suspect PTX. Few clues to distinguish skin fold from PTX on chest X-ray are:

Skin Folds
  • tends to extend beyond the rib cage
  • tends to gradually increase in opacity 
  • abrupt drop–off at the edge of the fold
  • blood vessels extend beyond the fold (can be seen with magnifying/zooming-in the x-ray)
#pulmonary


Reference:

Stark, P, Eber, C. Pneumothorax or skin fold? Clin Intensive Care 1993; 4:45.

Sunday, March 17, 2019

Cardiac cachexia

Q: All of the following are part of cardiac cachexia criteria except?

A) 10% edema-free body weight loss in the previous 12 months
B) Hb < 12 g/dL
C) serum albumin < 3.2 g/dL
D) a body mass index < 20 kg/m2
E) increased inflammatory markers


Answer: A

Cardiac cachexia is now a designated term. Cardiac failure leads to changes in all major organ physiology including nutritional status of the patient. It is now defined as "
at least 5% edema-free body weight loss in the previous 12 months."

All other choices are accepted standard in the criteria of general cachexia.



#cardiology

#nutrition


References:

1. Christensen HM, Kistorp C, Schou M, Keller N, Zerahn B, Frystyk J, et al. Prevalence of cachexia in chronic heart failure and characteristics of body composition and metabolic status. Endocrine. 2013;43(3):626–634. 

2. Trullas JC, Formiga F, Montero M, Carrera-Izquierdo M, Grau-Amorós J, Chivite-Guillén D, RICA Investigators et al. Impact of weight loss on mortality in chronic heart failure: findings from the RICA Registry. Int J Cardiol. 2013;168(1):306–311

Saturday, March 16, 2019

Difficult gender for intubation

Q: Which gender, in general, tends to present with more difficult airway? (select one)

A) Male
B) Female


Answer: A

The few well-known risk factors for difficult intubation are described by a mnemonic ROMAN

 R: Radiation or Restriction (Restriction includes neck immobility and intrinsic lung pathologies)
 O: Obstruction or Obesity or Obstructive Sleep Apnea
M: Mask Seal or (poor) Mallampati score or Male gender
A: Age (> 55)
N: No teeth – Edentulousness leads to difficult intubation

#procedures


References:

1. Walls R, Murphy M. Chapter 7: Identification of the Difficult Airway. Manual of Emergency Airway Management. Third Edition. Lippincott Williams & Wilkins 

2. Tulay Sahin Yildiz. Mine Solak. Kamil Toker. The incidence and risk factors of difficult mask ventilationJournal of Anesthesia February 2005, Volume 19, Issue 1, pp 7–11

Friday, March 15, 2019

Acute abdomen in CPAD patients

Q; 53 year old male on chronic continuous ambulatory peritoneal dialysis (CAPD) is admitted to ICU with acute abdominal pain. All of the following tests are important except?

A) Computed tomography (CT) scan of  abdomen and pelvis 

B) Peritoneal fluid spun hematocrit 
C) Peritoneal fluid cell count and differential 
D) Peritoneal fluid lipase 
E) Peripheral blood complete blood count (CBC)


Answer: D

Peritoneal fluid amylase (not lipase) of > 50 units/L in acute abdomen with patients having peritoneal dialysis catheter is a red flag for serious underlying damage. Second important test to look for is peritoneal fluid spun hematocrit. A level above 2 percent suggests significant intraperitoneal pathology.


 All other tests are expected to be on board in such scenarios.

#surgicalcriticalcare
#nephrology


References:

Lew SQ. Hemoperitoneum: bloody peritoneal dialysate in ESRD patients receiving peritoneal dialysis. Perit Dial Int 2007; 27:226.

Greenberg A, Bernardini J, Piraino BM, et al. Hemoperitoneum complicating chronic peritoneal dialysis: single-center experience and literature review. Am J Kidney Dis 1992; 19:252


Thursday, March 14, 2019

HIT Variants - Rx

Q; Q; Which intervention/drug can help when conventional treatments fail in cases with "Heparin Induced Thrombocytopenia (HIT) variants"?

 
Answer: Intravenous immune globulin (IVIG)

HIT variants is an umbrella term used for delayed onset, refractory or spontaneous HIT. These are severe and can be lethal clinical conditions, as patients continue to have all signs and symptoms of HIT even when heparin has been long withdrawn, other treatment modalities have been tried or even where there is no heparin exposure. These patients tend to have "HIT-like antibodies". IVIG is found to be effective in blocking further platelet activation in such situations. The recommended dose is 1 g/kg/day for two doses or 0.4 g/kg daily for five days. Please note anticoagulation with a non-heparin agent should be continued to reduce the risk of thrombosis.

#hematology


References:

1. Padmanabhan A, Jones CG, Pechauer SM, et al. IVIg for Treatment of Severe Refractory Heparin-Induced Thrombocytopenia. Chest 2017; 152:478. 


2. Ibrahim IF, Rice L. Intravenous Immunoglobulin for Heparin-Induced Thrombocytopenia. Chest 2017; 152:906. 

3. Azimov MB, Slater ED. Persistent Heparin-Induced Thrombocytopenia Treated With IVIg. Chest 2017; 152:679.

Wednesday, March 13, 2019

Blood gas, swan and cardiac arrest

Q; During cardiac arrest, which blood gas is more reliable?

A) Femoral artery (Arterial Blood Gas)
B) Pulmonary artery (Venous Blood Gas)


Answer:  B

During massive shock state arterial blood gas (ABG) does not accurately reflect the acid-base status as well as oxygenation at tissue levels. During such situation - given pulmonary artery catheter (PAC) is present - PH from PAC is the true indicator of the level of shock. In such scenarios, PH from ABG can be falsely high and can be very misleading. Unfortunately, PAC is not always present.

#hemodynanmic
#acid-base


References: 

1. Weil MH, Rackow EC, Trevino R, et al. Difference in acid-base state between venous and arterial blood during cardiopulmonary resuscitation. N Engl J Med 1986; 315:153. 

2. Adrogué HJ, Rashad MN, Gorin AB, et al. Assessing acid-base status in circulatory failure. Differences between arterial and central venous blood. N Engl J Med 1989; 320:1312.

Tuesday, March 12, 2019

tPA in cardiac arrest due to PE

Q: How the tPA should be given to a patient who is in cardiac arrest due to massive pulmonary embolism (PE)?


Answer:  During cardiac arrest, due to PE it is not practical to wait for standard two hours infusion. tPA is available as a 50 mg vial and an entire vial should be given as an IV bolus over two minutes. Another dose should be repeated after 15 minutes if a patient remains in cardiac arrest.

#hemodynamic

#cardiology
#pulmonary


Reference: 


Lavonas EJ, Drennan IR, Gabrielli A, et al. Part 10: Special Circumstances of Resuscitation: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation 2015; 132:S501.

Monday, March 11, 2019

blood volume loss and hemodynamic

Q: Supine hypotension in an acute gastrointestinal bleed (GIB) indicates at least what percentage of total body blood loss?


Answer: 40 percent

Assessment of hemodynamic provides a good clue of total blood loss. 

  • Only resting tachycardia is probably due to less than 15 percent of blood volume loss
  • Orthostatic hypotension is consistent with at least 15 percent of blood volume loss
  • Supine hypotension is consistent with at least 40 percent of blood volume loss

#gastroenterology

#hemodynamic


Reference:

1. Cappell MS, Friedel D. Initial management of acute upper gastrointestinal bleeding: from initial evaluation up to gastrointestinal endoscopy. Med Clin North Am 2008; 92:491.

Sunday, March 10, 2019

Grading of cardiac murmurs

Q: There are how many grades to classify the intensity of heart murmur?

Answer: Six 

There are six grades to classify the intensity of a cardiac murmur. The actual term is "Levine Grading scale". Another objective of this question is to highlight that - technically - the perfect way to auscultate cardiac murmurs is to compare the intensity of a murmur with first [S1] and second [S2] heart sounds 


  • Grade I: faintest murmur that can be heard only with difficulty; and murmur is usually softer than S1 and S2 sounds 
  • Grade II: faint murmur, which has the same intensity as S1 and S2 sounds 
  • Grade III: murmur auscultated relatively easy but not palpable as a thrill, and it is louder than the S1 and S2 sounds 
  • Grade IV: murmur auscultated relatively easy and palpable as a thrill, and it is louder than the S1 and S2 sounds 
  • Grade V: very loud with a thrill and can be heard with the slightest touch (only with the rim) of the stethoscope 
  • Grade VI: loudest and can be heard without a stethoscope
#physicalexam
#cardiology


Reference: 

Silverman ME, Wooley CF. Samuel A. Levine and the history of grading systolic murmurs. Am J Cardiol. 2008 Oct 15;102(8):1107-10.

Saturday, March 9, 2019

bleeding with direct oral anticoagulants (DOACs)

Q: If bleeding occurs with direct oral anticoagulants (DOACs), oral activated charcoal can be administrated if the last dose is within last two hours? (select one)

A) Yes
B) No



Answer: A

In case of bleeding with DOACs,, there is a Grade 2C recommendation to administer oral activated charcoal if the last anticoagulant dose is within the previous two hours for dabigatran and edoxaban, six hours for apixaban, and eight hours for rivaroxaban.


#hematology

#pharmacology
#toxicology


References:


1. Siegal DM, Garcia DA, Crowther MA. How I treat target-specific oral anticoagulant-associated bleeding. Blood 2014; 123:1152. 


2. Tomaselli GF, Mahaffey KW, Cuker A, et al. 2017 ACC Expert Consensus Decision Pathway on Management of Bleeding in Patients on Oral Anticoagulants: A Report of the American College of Cardiology Task Force on Expert Consensus Decision Pathways. J Am Coll Cardiol 2017; 70:3042. 

3. Kaatz S, Kouides PA, Garcia DA, et al. Guidance on the emergent reversal of oral thrombin and factor Xa inhibitors. Am J Hematol 2012; 87 Suppl 1:S141.

Friday, March 8, 2019

"Vitamin C, thiamine, and hydrocortisone combo"

Q: What is the logic behind adding thiamine into "Vitamin C, thiamine, and hydrocortisone combo" adjuvant treatment in sepsis?



Answer: Paul Marik recently demonstrated the benefit of using a combination of high dose vitamin C, thiamine, and stress dose hydrocortisone in patients with sepsis. High dose vitamin C may cause renal oxalate crystallization. Thiamine (vitamin B1) prevents this crystallization. 

The combination doses suggested are 

  • IV vitamin C - 1.5 g q 6 hours for four days or until ICU discharge
  • IV thiamine - 200 mg q 12 hours for four days or until ICU discharge 
  • IV hydrocortisone - 50 mg q 6 hours for seven days or until ICU discharge
#sepsis
#pharmacology


Reference: 

Marik PE, Khangoora V, Rivera R, et al. Hydrocortisone, Vitamin C, and Thiamine for the Treatment of Severe Sepsis and Septic Shock: A Retrospective Before-After Study. Chest 2017; 151:1229.

Thursday, March 7, 2019

anti-coagulation in AF - compared to warfarin

Q: Which of the following is found to be superior in preventing stroke or systemic embolism, lowers overall mortality and less major bleeding in comparison to warfarin, in a patient with atrial fibrillation? 

A) Dabigatran 
B) Rivaroxaban 
C) Apixaban 
D) Edoxaban
E) Asipirin


Answer: C

Out of all of the above, in a large trial of 18,000 patients (the ARISTOTLE trial), Apixaban was found to be superior in preventing stroke or systemic embolism, less major bleeding, and lowers overall mortality, when compared to dose adjusted warfarin.

Dabigatran, Rivaroxaban and Edoxaban when compared to warfarin were all found to be non-superior/inferior in their respective trials.

Aspirin is not an anticoagulation suggested for atrial fibrillation.

#cardiology
#pharmacology


References:

1. Connolly SJ, Ezekowitz MD, Yusuf S, et al. Dabigatran versus warfarin in patients with atrial fibrillation. N Engl J Med 2009; 361:1139. 

2. Patel MR, Mahaffey KW, Garg J, et al. Rivaroxaban versus warfarin in nonvalvular atrial fibrillation. N Engl J Med 2011; 365:883. 

3. Granger CB, Alexander JH, McMurray JJ, et al. Apixaban versus warfarin in patients with atrial fibrillation. N Engl J Med 2011; 365:981. 

4. Giugliano RP, Ruff CT, Braunwald E, et al. Edoxaban versus warfarin in patients with atrial fibrillation. N Engl J Med 2013; 369:2093.