"alarm findings" of preeclampsia

Q: All of the following are considered "alarm findings" of preeclampsia EXCEPT? (select one)

A) severe headache

B) blurred vision

C) epigastric pain

D) confusion

E) leg edema

Answer: E

Alarm findings in preeclampsia refer to the 'severe end of the disease spectrum.' It is a clinical emergency. This includes persistent and/or severe headache, visual changes such as scotomata, photophobia, blurred vision, temporary blindness, upper abdominal, retrosternal, or epigastric pain, confusion, and/or altered behavior, dyspnea and/or orthopnea.

The objective of this question is to emphasize nonspecific symptoms such as epigastric pain. Reflux is common in most pregnant patients and may go unnoticed but unbearable and/or persistent epigastric pain should be evaluated closely. Moreover, reflux symptoms are usually more pronounced at night.

Leg edema is almost universal in all pregnant patients

#ob-gyn

References:

1. Shi JM, Yang Z, Chen L, Wang JL. [Early warning signs of severe preeclampsia]. Zhonghua Fu Chan Ke Za Zhi. 2009 May;44(5):337-40. Chinese. PMID: 19573307.

2. Lambert G, Brichant JF, Hartstein G, Bonhomme V, Dewandre PY. Preeclampsia: an update. Acta Anaesthesiol Belg. 2014;65(4):137-49. PMID: 25622379.

cephalosporins in renal insufficiency

Q: Which of the following cephalosporins does not require adjustment in renal insufficiency? (select one)

A) Cefazolin

B) Cefuroxime

C) Ceftriaxone

D) Cefepime

E) Ceftaroline

Answer: C

There are five generations of cephalosporins. All cephalosporins require some level of dose adjustment in renal insufficiency, and in patients on hemodialysis (HD) or continuous renal replacement therapy (CRRT) except ceftriaxone. 

Clinicians should remember one caveat of ceftriaxone. A fatal reaction may occur due to calcium-ceftriaxone precipitates in the organs, particularly lungs and kidneys. This can be more pronounced in neonates. Ceftriaxone should not be mixed with any calcium-containing product like Ringer's or Hartmann's solutions, or parenteral nutrition. Similarly, should be avoided as an infusion from the same lines where calcium-containing products are being infused.

#pharmacology

Reference:

1. Lamb HM, Ormrod D, Scott LJ, Figgitt DP. Ceftriaxone: an update of its use in the management of community-acquired and nosocomial infections. Drugs. 2002;62(7):1041-89. doi: 10.2165/00003495-200262070-00005. PMID: 11985490.

2. Klein NC, Cunha BA. Third-generation cephalosporins. Med Clin North Am 1995; 79:705.

6 Ps of acute limb ischemia

Q; Which of the following is NOT among the classic six Ps of acute limb ischemia? (select one)

A) pain

B) pitting edema

C) poikilothermia

D) pulselessness

E) paresthesia

Answer: B

It is interesting that patients who develop acute limb ischemia have very quick and dramatic development of symptoms, and most of them can identify the exact time when symptoms began. This is due to the fact the underlying cause is an embolus. Although not present in all patients but famously known as 'Six Ps' are

• pain
• pallor
• poikilothermia
• pulselessness
• paresthesia
• paralysis

#surgical-critical-care

#vascular-surgery

#CVS

Further readings:

1. Olinic DM, Stanek A, Tătaru DA, Homorodean C, Olinic M. Acute Limb Ischemia: An Update on Diagnosis and Management. J Clin Med. 2019;8(8):1215. Published 2019 Aug 14. doi:10.3390/jcm8081215 

2. Hess CN, Huang Z, Patel MR, Baumgartner I, Berger JS, Blomster JI, Fowkes FGR, Held P, Jones WS, Katona B, Mahaffey KW, Norgren L, Rockhold FW, Hiatt WR. Acute Limb Ischemia in Peripheral Artery Disease. Circulation. 2019 Aug 13;140(7):556-565. doi: 10.1161/CIRCULATIONAHA.119.039773. Epub 2019 Jun 26. PMID: 31238713.

IV steroid in toxic megacolon due to IBD

Q: 54 years old male with known ulcerative colitis is admitted to ICU with megacolon. Intravenous (IV) steroid is started. This may increase the risk of bowel perforation.

A) True

B) False

Answer: B

There are three major objectives for toxic megacolon management in inflammatory bowel disease (IBD)

1. reduce inflammation

2. restore colonic motility

3. decrease the risk of perforation

Almost half of the patients recover with supportive and medical management.

The mainstay of treatment is bowel rest, nasogastric tube (NGT), Intravenous fluid (IVF), electrolyte repletion, and total parenteral nutrition (TPN). Less emphasized is the early initiation of enteral feed if patients can tolerate it as it expedites mucosal healing and motility. Non-pharmacologic interventions such as periodic rolling maneuvers and the knee-elbow position have been described in the past and may help.

So far there is no evidence that IV glucocorticoids increase the risk of perforation.

#surgical-critical-care

References:

1. Norland CC, Kirsner JB. Toxic dilatation of colon (toxic megacolon): etiology, treatment and prognosis in 42 patients. Medicine (Baltimore) 1969; 48:229. 

2.  Autenrieth DM, Baumgart DC. Toxic megacolon. Inflamm Bowel Dis 2012; 18:584. 

3. Present DH, Wolfson D, Gelernt IM, et al. Medical decompression of toxic megacolon by "rolling". A new technique of decompression with favorable long-term follow-up. J Clin Gastroenterol 1988; 10:485. 

4. Panos MZ, Wood MJ, Asquith P. Toxic megacolon: the knee-elbow position relieves bowel distension. Gut 1993; 34:1726.

sweating - a side-effect of drugs

Q: Which of the following group of drugs are most likely to cause increase sweating/night sweats? (select one)

A) Antidepressants 

B) Cholinergic agents 

C) Hypoglycemic agents 

D) Estrogen/androgen modulating agents

E) Albuterol / sympathomimetics

Answer: A

Night sweats or increased sweating has usually been attributed either to infections or malignancies. The objective of this question is to highlight the fact that medications are a less known but a potential cause of this symptom. In ICU, it is common to miss patients home medications' list.

Antidepressants are widely used in population and are most common to cause increased sweating which may get more noticed at night by patients. All other choices in above question (B,C, D and E) are also known to cause such symptoms but antidepressants take the lead. Tricyclics, bupropion, venlafaxine, desipramine and duloxetine are well known in this regard.

#pharmacology

References:

1. Cheshire WP, Fealey RD. Drug-induced hyperhidrosis and hypohidrosis: incidence, prevention and management. Drug Saf 2008; 31:109.

2. Trindade E, Menon D, Topfer LA, Coloma C. Adverse effects associated with selective serotonin reuptake inhibitors and tricyclic antidepressants: a meta-analysis. CMAJ 1998; 159:1245. 

3. Riediger C, Schuster T, Barlinn K, et al. Adverse Effects of Antidepressants for Chronic Pain: A Systematic Review and Meta-analysis. Front Neurol 2017; 8:307.

Propofol and pupillary diameter

Q: Propofol has a dose-dependent effect on pupillary diameter?

A) True

B) False

Answer: A

A less known clinical effect of propofol is its dose-dependent effect on pupillary diameter. It has an inverse relationship with pupillary diameter. Moreover, this dose-dependent effect correlates well with bispectral index (BIS) value. A recent randomized trial of 40 patients from France confirmed this relationship. This is probably due to propofol's subcortical effect on pupillary diameter, and it correlates with its effect on the cortex (aka BIS value). 

This can be a valuable clinical tool at bedside to gauge the depth of hypnosis.

#pharmacology

#neurology

Reference:

Sabourdin N, Meniolle F, Chemam S, et al. Effect of Different Concentrations of Propofol Used as a Sole Anesthetic on Pupillary Diameter: A Randomized Trial. Anesth Analg 2020; 131:510.

Bovis and colonic CA

Q: Which of the streptococcus bovis (S.Bovis) biotype is associated with increased risk of colonic neoplasia and infective endocarditis (IE)? (select one)

A) biotype I

B) biotype II 

Answer: A

Although not fully explained but the most probable reason for this association is the presence of proteins in S. bovis biotype I that bind to overexpressed ligands in colonic neoplasms. This association is independent and have an extremely high odds ratio [OR] of 5.7. Patients who develop S. bovis IE are likely to have colonic neoplasia.

Less known fact is that similar association has been described with other gastrointestinal tract diseases such as gastric carcinoma, polyps, lymphoma, and colitis.

#oncology

#cardiology

#GI

References:

1. Boleij A, van Gelder MM, Swinkels DW, Tjalsma H. Clinical Importance of Streptococcus gallolyticus infection among colorectal cancer patients: systematic review and meta-analysis. Clin Infect Dis 2011; 53:870.

2. Corredoira-Sánchez J, García-Garrote F, Rabuñal R, et al. Association between bacteremia due to Streptococcus gallolyticus subsp. gallolyticus (Streptococcus bovis I) and colorectal neoplasia: a case-control study. Clin Infect Dis 2012; 55:491.

3. Ballet M, Gevigney G, Garé JP, et al. Infective endocarditis due to Streptococcus bovis. A report of 53 cases. Eur Heart J 1995; 16:1975.

4. Corredoira JC, Alonso MP, García-País MJ, et al. Is colonoscopy necessary in cases of infection by Streptococcus bovis biotype II? Eur J Clin Microbiol Infect Dis 2014; 33:171.

Small bowel vs colon as source of diarrhea

Q: All of the following are sources of diarrhea from the colon except? (select one)

A) Vibrio cholerae

B) Shigella

C) Clostridioides difficile

D) Yersinia

E) Enteroinvasive E. coli

Answer: A

The objective of this question is to highlight the importance of proper history during clinical exams. Subsequently, it may guide towards the appropriate diagnosis. The probable bugs in diarrhea are usually either in the small bowel or colon, which may have different characteristics of diarrhea. Diarrhea of small bowel origin is usually large volume, watery, and results in cramps, gas, and bloating. Fever is unlikely. In contrast, diarrhea from colon is small volume and associated with painful bowel movements. Fever and blood/mucoid in stool are common. Inflammatory cells are seen on stool microscopy, which is unlikely in small bowel diarrhea.

Salmonella, Escherichia coli, Clostridium perfringens, Staphylococcus aureus, Bacillus cereus, and Vibrio cholerae usually originate in the small bowel.

Shigella, Clostridioides difficile, Yersinia, and Enteroinvasive E. coli are mostly found in the colon.

#GI

#ID

References: 

1. Lam C, Chaddock G, Marciani Laurea L, Costigan C, Cox E, Hoad C, Pritchard S, Gowland P, Spiller R. Distinct Abnormalities of Small Bowel and Regional Colonic Volumes in Subtypes of Irritable Bowel Syndrome Revealed by MRI. Am J Gastroenterol. 2017 Feb;112(2):346-355. doi: 10.1038/ajg.2016.538. Epub 2016 Dec 13. PMID: 27958282; PMCID: PMC5318666.

2. Sweetser S. Evaluating the patient with diarrhea: a case-based approach. Mayo Clin Proc. 2012;87(6):596-602. doi:10.1016/j.mayocp.2012.02.015

3. Murray JA, Rubio-Tapia A. Diarrhoea due to small bowel diseases. Best Pract Res Clin Gastroenterol. 2012;26(5):581-600. doi:10.1016/j.bpg.2012.11.013

Provocative angiography

Q: What is provocative Angiography?

Answer: Provocative angiography is rarely applied in lower gastrointestinal bleed (GIB), in case the site of bleeding cannot be identified by other conventional methods. 

Provocative challenge is given with vasodilators, anticoagulants, and/or thrombolytics. The commonly used agents are urokinase, heparin, nicardipine in 3 cases, alprostadil, and isosorbide.       

Although seem paradoxical but can be an effective way of identifying the area of bleed where there is a high risk of mortality.

#procedures

Reference:

Kariya S, Nakatani M, Ono Y, Maruyama T, Ueno Y, Yoshida A, Komemushi A, Tanigawa N. Provocative angiography for lower gastrointestinal bleeding. Jpn J Radiol. 2020 Mar;38(3):248-255. doi: 10.1007/s11604-019-00909-0. Epub 2019 Dec 13. PMID: 31834578.

Linezolid induced LA

Q; Lactic acidosis from Linezolid usually clears quickly once the drug is stopped.

A) True

B) False

Answer: B

Lactic acidosis from linezolid can be fatal. It usually occurs in patients on long-term infusion but may occur in ICU within a week of administration. The mechanism of action is secondary to mitochondrial toxicity. 

It may take up to 14 days for lactate levels to normalize.

#acid-base

#pharmacology

References:

1. Santini A, Ronchi D, Garbellini M, et al. Linezolid-induced lactic acidosis: the thin line between bacterial and mitochondrial ribosomes. Expert Opin Drug Saf 2017; 16:833. 

2. Wiener M, Guo Y, Patel G, Fries BC. Lactic acidosis after treatment with linezolid. Infection 2007; 35:278. 

3. Apodaca AA, Rakita RM. Linezolid-induced lactic acidosis. N Engl J Med 2003; 348:86.

Median time intervals of different anaphylaxes

Q: What is the median time interval between onset of symptoms and respiratory or cardiac arrest in iatrogenic anaphylaxis? (select one)

A) 5 minutes 

B) 15 minutes 

C) 30 minutes 

Answer: A

Although every human is different, at least one study found the ballpark figure of different median time interval between onset of symptoms and respiratory or cardiac arrest:

• iatrogenic anaphylaxis - 5 minutes
• stinging insect venom-induced anaphylaxis - 15 minutes
• food-induced anaphylaxis - 30 minutes

This is a good reminder for clinicians who encounter in-patient anaphylaxes.

#allergy

Reference:

Pumphrey RS. Lessons for management of anaphylaxis from a study of fatal reactions. Clin Exp Allergy 2000; 30:1144.

Platypnea-orthodeoxia syndrome

Q: What is platypnea-orthodeoxia syndrome?

Answer: Platypnea-orthodeoxia syndrome is characterized by both dyspnea (platypnea) and desaturation (orthodeoxia) in upright position but improve in supine position. It is usually due to high right atrial pressure causing right-to-left shunting. Some of the major reasons are patent foramen ovale (PFO), pericardial effusion, constrictive pericarditis, emphysema, amiodarone pulmonary toxicity, pneumonectomy, and cirrhosis.

#pulmonary

#cardiology

References:

1. Cheng TO. Platypnea-orthodeoxia syndrome: etiology, differential diagnosis, and management. Catheter Cardiovasc Interv 1999; 47:64.

2. Rodrigues P, Palma P, Sousa-Pereira L. Platypnea-orthodeoxia syndrome in review: defining a new disease? Cardiology. 2012;123(1):15-23. doi: 10.1159/000339872. Epub 2012 Aug 31. PMID: 22948714.

Timing of Type B AD

Q: Hyperacute phase of acute type B aortic dissection is? (select one)

A) <12 hours

B) <24 hours

Answer: B

 

Conventionally Type B aortic dissection is classified as acute (less than 14 days) or chronic (more than14 days). Recently, the Society for Vascular Surgery (SVS) and Society of Thoracic Surgeons (STS) has updated the reporting standards for type B aortic dissections from the onset of symptoms:

• Hyperacute: <24 hours
• Acute: 1 to 14 days
• Subacute: 15 to 90 days
• Chronic: >90 days

#vascular

#cardio-thoracic

Reference:

Lombardi JV, Hughes GC, Appoo JJ, et al. Society for Vascular Surgery (SVS) and Society of Thoracic Surgeons (STS) reporting standards for type B aortic dissections. J Vasc Surg 2020; 71:723.

Leriche syndrome

Q: What is Leriche syndrome?

Answer: Leriche syndrome is described seven decades ago as a part of bedside clinical exam of peripheral arterial disease (PAD). It is the triad of 

• claudication
• absent or diminished femoral pulses
• erectile dysfunction

Despite the availability of angiograms and other radiological modalities, bedside exams continue to be the first line of diagnostic evaluation in PAD.

#vascular

#surgical-critical-care

References:

1. Leriche R, Morel A. The Syndrome of Thrombotic Obliteration of the Aortic Bifurcation. Ann Surg 1948; 127:193.

2. Frederick M, Newman J, Kohlwes J. Leriche syndrome. J Gen Intern Med 2010; 25:1102.

TTBI

Q: The incidence/risk of transfusion-transmitted bacterial infection (TTBI) is higher than the transfusion-transmitted viral infection (TTVI)?

A) True

B) False

Answer: A

It is a less known fact that TTBI can occur not only through the donor blood but can also occur through the donor skin phlebotomist's skin, or during preparation and packaging of the product. In case TTBI occurs, four bacterias should be highly considered:

• Yersinia enterocolitica 
• Pseudomonas fluorescens 
• Enterobacter 
• Serratia

These bacteria are capable of multiplying in cold.

#transfusion

#ID

References:

1. Vasconcelos E, Seghatchian J. Bacterial contamination in blood components and preventative strategies: an overview. Transfus Apher Sci 2004; 31:155. 

2. Jacobs MR, Palavecino E, Yomtovian R. Don't bug me: the problem of bacterial contamination of blood components--challenges and solutions. Transfusion 2001; 41:1331. 

3. Sugai Y, Sugai K, Fuse A. Current status of bacterial contamination of autologous blood for transfusion. Transfus Apher Sci 2001; 24:255. 

4. Casewell MW, Slater NG, Cooper JE. Operating theatre water-baths as a cause of pseudomonas septicaemia. J Hosp Infect 1981; 2:237. 

5. Wagner SJ. Transfusion-transmitted bacterial infection: risks, sources and interventions. Vox Sang 2004; 86:157. 

Spasticity and Rigidity

Q: What is the difference between spasticity and rigidity?

  

Answer: Simple clinical exam at the bedside provides various clues to the underlying pathology. During neuro exam, it may be of importance to differentiate between spasticity and rigidity.

Spasticity is also known as "clasp-knife phenomenon". Here a limb moves freely for a little while, then there is a "catch" requiring a force to move the limb, followed by a sudden release, and limb move freely again. 

Rigidity requires increased resistance throughout the movement and get accentuated by distracting the patient. There are two kinds of rigidity. When resistance is uniform throughout the movement, is called Lead-pipe rigidity. In contrast, resistance which has rhythmic interruption is called Cogwheel rigidity.

It would be of interest to know the difference between these two phenomena is intriguing academicians for the last six decades (see reference # 2).

#neurology

#clinical-exam

References:

1. Fearon C, Doherty L, Lynch T. How Do I Examine Rigidity and Spasticity?. Mov Disord Clin Pract. 2015;2(2):204. Published 2015 Mar 28. doi:10.1002/mdc3.12147

2. HERMAN R. The physiologic basis of tone, spasticity and rigidity. Arch Phys Med Rehabil. 1962 Mar;43:108-14. PMID: 13906696.

Myxedema

Q: Edema in myxedema is usually? (select one)

A) pitting 

B) non-pitting 

Answer: B

The objective of this question is to underline the importance of bedside clinical exam. The two hallmarks clinical signs of myxedema  are

• mental status change, and
• hypothermia (may mask signs of infection)

Other common signs are hypotension, low respiratory and heart rate, hyponatremia, hypoglycemia, puffiness of the hands and face, a thickened nose, swollen lips, and an enlarged tongue. The nonpitting edema is due to deposits of albumin and mucin in the skin and other tissues, known as myxedema.

#endocrine

References:

1. Ono Y, Ono S, Yasunaga H, et al. Clinical characteristics and outcomes of myxedema coma: Analysis of a national inpatient database in Japan. J Epidemiol 2017; 27:117. 

2. Wiersinga WM. Myxedema and Coma (Severe Hypothyroidism) [Updated 2018 Apr 25]. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK279007/

PPH - predictor

Q: Which of the following is a good predictor of postpartum hemorrhage (PPH)? (select one)

A) low fibrinogen 

B) hypotension

C) tachycardia

D) low hematocrit 

Answer: A

Low blood pressure and tachycardia usually do not manifest in pregnant patients till late and are a poor indicator of ongoing PPH (choice B and C). On the same token, in severe acute hemorrhage, it takes time before hematocrit shows a drop in the laboratory (choice D).

A fibrinogen level below 200 mg/dL is a reliable predictor of severe PPH, where massive blood transfusion or surgical/procedural intervention is required (choice A).

#ob-gyn

#surgical-critical-care

Reference:

1. Bell SF, Collis RE, Bailey C, et al. The incidence, aetiology, and coagulation management of massive postpartum haemorrhage: a two-year national prospective cohort study. Int J Obstet Anesth 2021; 47:102983.

2. Bonnar J. Massive obstetric haemorrhage. Baillieres Best Pract Res Clin Obstet Gynaecol 2000; 14:1.

bag-mask ventilation in an edentulous patient

Q: Describe few tricks to have proper mask seal in edentulous patients during bag-mask ventilation?

Answer: Edentulous patients offer a challenge to have proper mask seal during bag-mask ventilation. Few tricks which may help:

1. Reinsert the false teeth.

2. Expand cheeks with 4 x 4 gauze.

3. Lower lip placement of mask : The caudad end of the face mask is positioned between the lower lip and the alveolar ridge.

4. Perform two-handed thenar eminence method: The index fingers lift the soft tissue of the cheeks against the rim of the facemask, while the remaining three fingers pull the jaw upward.

#procedures

References: 

1. Conlon NP, Sullivan RP, Herbison PG, et al. The effect of leaving dentures in place on bag-mask ventilation at induction of general anesthesia. Anesth Analg 2007; 105:370. 

2. Racine SX, Solis A, Hamou NA, et al. Face mask ventilation in edentulous patients: a comparison of mandibular groove and lower lip placement. Anesthesiology 2010; 112:1190. 

3. Jain D, Sahni N, Goel N, et al. The C-E versus modified V-E hand positions for holding a face mask when ventilating an edentulous patient: A randomised crossover trial. Eur J Anaesthesiol 2021; 38:1194.

Coffee Bean sign

Q: What is "Bent Inner Tube" sign?

Answer: pathognomonic sign of sigmoid volvulus  

Sigmoid volvulus may presents as a U-shaped, distended sigmoid colon, which may appear as an ahaustral collection of gas extending from the pelvis to the right upper quadrant up to the diaphragm. This is highly suggestive but not a confirmatory sign. CT scan should be performed. This can also be present in other causes of distal colonic obstruction, colonic pseudo-obstruction, and toxic megacolon. It is also referred to as coffee bean, kidney bean or omega sign.

Image used from Wikimedia Commons, the free media repository.

#surgical-critical-care

#ID

Reference:

Stavride E, Plakias C. Coffee bean sign: Its meaning and importance. Clin Case Rep. 2020 Jun 26;8(10):2086-2087. doi: 10.1002/ccr3.3064. PMID: 33088563; PMCID: PMC7562879.

MESA score

Q: MESA risk score for cardiovascular disease includes? (select one)

A) Ethnic background

B) Estrogen use

Answer: A

The Multi-Ethnic Study of Atherosclerosis (MESA) is a validated risk score published in 2015. This calculator looks for African American, Chinese American, Hispanic, and Non-Hispanic white backgrounds. MESA also allows an option to incorporate coronary artery calcium (CAC) score.

Calculator can be found at 

https://www.mesa-nhlbi.org/MESACHDRisk/MesaRiskScore/RiskScore.aspx.

#cardiology

Reference:

1. McClelland RL, Jorgensen NW, Budoff M, et al. 10-Year Coronary Heart Disease Risk Prediction Using Coronary Artery Calcium and Traditional Risk Factors: Derivation in the MESA (Multi-Ethnic Study of Atherosclerosis) With Validation in the HNR (Heinz Nixdorf Recall) Study and the DHS (Dallas Heart Study). J Am Coll Cardiol 2015; 66:1643.

IV to PO morphine

 Q: What is an estimated IV to PO conversion ratio of Morphine?

Answer: 1:3

While converting intravenous (IV) to oral (PO) opioids two principles should be kept in mind 

1. Conservative estimates should be used.
2. The optimal dose should be found with judicious titration due to the fact that cross-tolerance equivalency is not established.

#pharmacology

Reference:

Calculating Conversations in Opioid Conversions 

url: https://www.fda.gov/media/150396/download (last accessed March 11, 2021)

CBC reading

Q: 47 years old African-American male is admitted to ICU with acute bleeding due to esophageal varices. Serial CBC shows, a parallel decrease in Hemoglobin (Hb) and Hematocrit (HCT) but an inverse increase in RBC count. What could be the underlying disease?

Answer: Thalassemia

In patients with anemia, Hb, HCT, and RBC count usually decrease in parallel except in patients with thalassemia. This is due to severe microcytosis.

The incidence of thalassemia is relatively high in the African-American population and suggests the underlying pathology of thalassemia.

#hematology

Reference:

Munkongdee T, Chen P, Winichagoon P, Fucharoen S, Paiboonsukwong K. Update in Laboratory Diagnosis of Thalassemia. Front Mol Biosci. 2020 May 27;7:74. doi: 10.3389/fmolb.2020.00074. PMID: 32671092; PMCID: PMC7326097.

Dialysis in TLS

Q: Which of the following is NOT an indication for early dialysis in patients with Tumor Lysis Syndrome (TLS)? (select one)

A) hyperkalemia

B) Hyperphosphatemia

C) hypercalcemia

D) High uric acid

Answer: C

The objective of this question is to highlight the low threshold of initiating dialysis in patients who develop TLS. This low threshold is due to two reasons:

1. Hyperkalemia occurs relatively fast in TLS due to rapid potassium release and can be fatal with superimposed oliguria. 

2. Rapid reduction of uric acid and phosphate levels is vital in preventing End-Stage Renal Disease (ESRD).

Usually, symptomatic hypocalcemia (not hypercalcemia) is a norm in TLS. This is due to hyperphosphatemia (choice C).

#nephrology

#oncology

References:

1. Cairo MS, Bishop M. Tumour lysis syndrome: new therapeutic strategies and classification. Br J Haematol 2004; 127:3.

2. Tan HK, Bellomo R, M'Pis DA, Ronco C. Phosphatemic control during acute renal failure: intermittent hemodialysis versus continuous hemodiafiltration. Int J Artif Organs 2001; 24:186.

Osborn wave

Q: 48 years old homeless male is brought to ED at Chicago downtown hospital with severe hypothermia. EKG was found to have a characteristic J point elevation (Osborn wave). J point elevation in hypothermia correlates with the degree of hypothermia?

A) Yes

B) No

Answer: A

Along with bradycardia hypothermia produces a classic J point elevation, known as Osborn wave. This elevation correlates with the degree of hypothermia. Osborn wave can be best seen from lead V2 to lead V5. Care should be taken to make sure that any other ST-segment elevation is not missed due to this wave. 

It is essential that a clinician personally evaluates all EKGs in hypothermia so as not to miss any cardiac ischemia findings (automatic machine readings may not be reliable).

Said that many other conditions can give similar EKG appearance such as early repolarization, hypercalcemia, and Brugada syndrome. Although suggestive of hypothermia, subarachnoid hemorrhage (SAH), and traumatic brain injury (TBI).

#cardiology

#hypothermia

References:

1. Doshi HH, Giudici MC. The EKG in hypothermia and hyperthermia. J Electrocardiol 2015; 48:203. 

2. Graham CA, McNaughton GW, Wyatt JP. The electrocardiogram in hypothermia. Wilderness Environ Med 2001; 12:232. 

3. Salinski EP, Worrilow CC. ST-segment elevation myocardial infarction vs. hypothermia-induced electrocardiographic changes: a case report and brief review of the literature. J Emerg Med 2014; 46:e107.

Causes of WE

Q: Describe few causes of Wernicke encephalopathy (WE) besides chronic alcoholism?

Answer: The objective of this question is to highlight the stereotyping of WE occurring only in patients with chronic alcoholism. About one-forth of patients with WE has a cause other ETOH abuse. There are many other causes of WE. Any or combination of following four factors of thiamine deficiency can cause WE.

1.  inadequate dietary intake
2. decreased gastrointestinal (GI) absorption, 
3. reduced liver storage, and 
4. impaired utilization

Some of the conditions beside chronic alcohol abuse which can cause WE are

• Anorexia nervosa 
• Poor diet
• Hyperemesis gravidarum
• GI pathology 
• Bariatric surgery
• Malignancy 
• Transplant
• Hemo or peritoneal dialysis
• AIDS
• Genetic disorder of thiamine metabolism 

#neurology

#vitamins

References:

1. Lindboe CF, Løberg EM. Wernicke's encephalopathy in non-alcoholics. An autopsy study. J Neurol Sci 1989; 90:125.

2. Sechi G, Serra A. Wernicke's encephalopathy: new clinical settings and recent advances in diagnosis and management. Lancet Neurol. 2007 May;6(5):442-55. doi: 10.1016/S1474-4422(07)70104-7. PMID: 17434099.

Cholestyramine in thyroid storm

Q: 24 years old female is admitted to ICU with thyroid storm. Endocrine service suggested adding cholestyramine. How does it help in thyroid storm?

Answer: By default, thyroid hormones are hepatically metabolized. They get conjugated with glucuronide and sulfate, and these conjugated products get excreted in bile. Free thyroid hormones are released in intestine and are reabsorbed. Cholestyramine is a bile acid sequestrant. It interrupts T3, T4 enterohepatic circulation and thus recycling of thyroid hormone. It is a valuable adjuvant treatment in thyroid storm, particularly in patients who are thionamides intolerant.

#endocrine

References:

1. Solomon BL, Wartofsky L, Burman KD. Adjunctive cholestyramine therapy for thyrotoxicosis. Clin Endocrinol (Oxf) 1993; 38:39. 

2. Kaykhaei MA, Shams M, Sadegholvad A, et al. Low doses of cholestyramine in the treatment of hyperthyroidism. Endocrine 2008; 34:52.

3. Tsai WC, Pei D, Wang TF, et al. The effect of combination therapy with propylthiouracil and cholestyramine in the treatment of Graves' hyperthyroidism. Clin Endocrinol (Oxf) 2005; 62:521.

COVID, cancer and DVT

 Q: Cancer patients who develop COVID-19 infection are more prone to develop thrombosis than non-cancer patients? (select one)

A) True

B) False

Answer: B

Although in general cancer patients are more at risk for developing Deep Venous Thromboses (DVTs) but fortunately, COVID-19 infection doesn't increase that risk, despite the hypercoagulability tendency of COVID-19. This applies to both arterial and venous thromboses. 

To date, there is no evidence that cancer patients with COVID-19 should be treated more aggressively for the prevention of thromboses.

#oncology

#COVID-19

#hematology

Reference:

Patell R, Bogue T, Bindal P, et al. Incidence of thrombosis and hemorrhage in hospitalized cancer patients with COVID-19. J Thromb Haemost 2020; 18:2349.

ARB and enteropathy

Q: 58 years old male with history of hypertension but stable on a single medicine for the last two years is admitted to ICU with worsening diarrhea, hypovolemia, and impending kidney failure. Which of the following anti-hypertensive is more prone to produce "sprue-like enteropathy"? (select one)

A) Irbesartan (Avapro)

B) Losartan (Cozaar)

C) Olmesartan (Benicar)

D) Valsartan (Diovan)

E) Candesartan (Atacand)

 Answer: C

  One of the popular angiotensin II receptor blockers (ARBs) olmesartan is associated with "sprue-like enteropathy". Although intestinal biopsy shows villous atrophy, though antibody testing for celiac disease stays negative. Diagnosis is based on rechallenging the drug, clinical symptoms, and intestinal biopsy. ACE inhibitors or other ARBs have not been implicated yet.

#pharmacology

#GI

References:

1. Ianiro G, Bibbò S, Montalto M, et al. Systematic review: Sprue-like enteropathy associated with olmesartan. Aliment Pharmacol Ther 2014; 40:16.

2. Basson M, Mezzarobba M, Weill A, et al. Severe intestinal malabsorption associated with olmesartan: a French nationwide observational cohort study. Gut 2016; 65:1664.

3. Talley NJ. Use of olmesartan for ≥ 1 year was associated with hospitalization for intestinal malabsorption. Ann Intern Med 2015; 163:JC13.