Sunday, October 24, 2021

HELLP

 Q: To establish the diagnosis of HELLP syndrome, the cut-off point for platelet count is? (select one)

A) Less than 10,000 cells/microL 

B) Less than 50,000 cells/microL 

C) Less than 100,000 cells/microL 

D) No established cutoff point for low platelets


Answer: C

HELLP syndrome which stands for hemolysis, elevated liver enzymes, and low platelets usually occurs between 28 and 37 weeks of gestation and can be fatal. There are many criteria established to diagnose this syndrome. Most criteria depend on laboratory work to establish the above three entities of the syndrome including blood smear. 

Blood workup usually includes serum bilirubin, haptoglobin, lactate dehydrogenase (LDH), hematocrit, AST, ALT, and platelets levels. Most criteria accept platelet levels below 100,000 cells/microL. 

Infrequently used is the Mississippi classification, which further subclassifies HELLP syndrome depending on its severity.

#Ob-gyn

#hematology


References:

1. Audibert F, Friedman SA, Frangieh AY, Sibai BM. Clinical utility of strict diagnostic criteria for the HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome. Am J Obstet Gynecol 1996; 175:460. 

2. Ditisheim A, Sibai BM. Diagnosis and Management of HELLP Syndrome Complicated by Liver Hematoma. Clin Obstet Gynecol 2017; 60:190. 

3. Gestational Hypertension and Preeclampsia: ACOG Practice Bulletin, Number 222. Obstet Gynecol 2020; 135:e237.

Saturday, October 23, 2021

Switching of DOAC

 Q: Switching from one Direct Oral Anticoagulant (DOAC) to another should be done with a space of 48-72 hours?

A) True

B) False


Answer: B

Currently, there are four DOACs approved for use in the USA. 

  • dabigatran 
  • rivaroxaban 
  • apixaban 
  • edoxaban
Due to various reasons i.e., availability, insurance authorization, tolerance, or patient preference - clinicians may need to switch from one DOAC to another. The beauty is that one DOAC can be switched to another DOAC without any interruption or overlap. The second DOAC can be continued when the next dose of the first DOAC is due.

#hematology
#pharmacology


References:

1. Oyakawa T, Muraoka N, Iida K, Kusuhara M. Effect of Switching from the Initial Direct Oral Anticoagulant to Another One on Exacerbation of Venous Thromboembolism in Patients with Cancer: A Retrospective Study. Ann Vasc Dis. 2018;11(4):531-534. doi:10.3400/avd.oa.18-00072 

2. Marchetti G, Bernardini F, Romoli M, Urbinati S. Switching across direct oral anticoagulants: a real-life-setting pilot prospective study. J Cardiovasc Med (Hagerstown). 2021 Jun 1;22(6):453-458. doi: 10.2459/JCM.0000000000001118. PMID: 33186238.

3. Romoli M, Marchetti G, Bernardini F, Urbinati S. Switching between direct oral anticoagulants: a systematic review and meta-analysis. J Thromb Thrombolysis. 2021 Jan 2. doi: 10.1007/s11239-020-02367-2. Epub ahead of print. PMID: 33389613.

Friday, October 22, 2021

HBS

 Q: 54 years old male with End-Stage Renal Disease (ESRD) is postoperative parathyroidectomy. The patient is transferred from the floor to ICU on a postoperative day #3 due to clinical symptoms of "Hungry Bone Syndrome" (HBS). All of the following are the feature of HBS EXCEPT?

A) hypocalcemia 

B) hypophosphatemia 

C) hypomagnesemia 

D) hypokalemia


Answer: D

Hypocalcemia immediately after parathyroidectomy is almost always universal. Usually, it is transient but ESRD patients have a high tendency to go into hypocalcemia crisis and it may last longer. 

In hyperparathyroidism, parathyroid hormone (PTH) increases bone formation and resorption with a net efflux of calcium from bone, resulting in hypercalcemia. The acute withdrawal of the parathyroid hormone (PTH) results in an imbalance resulting in a marked bone uptake of calcium, phosphate, and magnesium. The overall indirect effect on electrolytes is hyperkalemia, particularly in renal patients.


#electrolytes

#endocrinology

#surgical-critical-care


References:

1. Cruz DN, Perazella MA. Biochemical aberrations in a dialysis patient following parathyroidectomy. Am J Kidney Dis 1997; 29:759. 

2. Shpitz B, Korzets Z, Dinbar A, et al. Immediate postoperative management of parathyroidectomized hemodialysis patients. Dial Transplant 1986; 15:507.

Thursday, October 21, 2021

CS in HbS

 Q: What is the caveat of using Cell Saver (CS) in patients with sickle cell disease and sickle cell trait (HbS)? 

Answer:  Cell saver use in patients with sickle cell disease or trait may cause harm. The washing process during CS may cause hemolysis or sickling of red blood cells with HbS. 

By default "Sickled RBCs" are prothrombotic. Dehydration, hypotension, acidosis, low cardiac index, hyperthermia, post-op shivering are major risk factors in these patients. 

In elective surgery, preoperative optimization is the best strategy. African-American patients have a higher rate of sickle cell disease and should be particularly managed. In high risk patients, hemoglobin electrophoresis should be strongly considered prior to surgery. To avoid delay in blood products during surgery, type and cross with presence/absence of antibodies (from previous transfusions) should be established. During surgery adequate hydration is of paramount importance. . 

In cardiac surgery centrifugal cardio-pulmonary-bypass (CPB) pump is preferred.

#surgical-critical-care

#hematology


References:

1. Chabot D, Sutton R. Mitral valve replacement in a patient with sickle cell disease using perioperative exchange transfusion. J Extra Corpor Technol 2008; 40:275. 

2. You D, Peiro-Garcia A, Ferri-de-Barros F, Parsons D. Hemolysis Following Intraoperative Cell Salvage Replacement in a Scoliosis Patient With Sickle Cell Trait: A Case Report. Spine (Phila Pa 1976) 2017; 42:E1331. 

3. Okunuga A, Skelton VA. Use of cell salvage in patients with sickle cell trait. Int J Obstet Anesth. 2009;18(1):90-91. doi:10.1016/j.ijoa.2008.06.010

Wednesday, October 20, 2021

lytes and ASA poisoning

 Q: Which of the following electrolyte should be treated aggressively in salicylate poisoning? (select one)

A) Sodium

B) Potassium

C) Chloride

D) Phosphate

E) Calcium


Answer: B

Hypokalemia can be detrimental and a barrier in the treatment of salicylate poisoning. The close relationship of potassium and salicylate was first realized during tuberculosis treatments almost 7 decades ago. 

The mainstay of treatment in salicylate overdose is alkalinization of urine. Hypokalemia leads to absorption of K+ in the distal tubule via exchange at the K+/H+ pump. Absorption of K+ promotes excretion of H+ in urine and hampers the alkalinization of urine. 

Hypokalemia should be repleted aggressively in salicylate toxicity.


#toxicology

#electrolytes


References:

1. HEARD KH, CAMPBELL AH, HURLEY JJ, FERGUSON E. Hypokalaemia complicating sodium para-amino-salicylate therapy for pulmonary tuberculosis. Med J Aust. 1950 Oct 21;2(17):606-12. PMID: 14785411. 

2. ROBIN ED, DAVIS RP, REES SB. Salicylate intoxication with special reference to the development of hypokalemia. Am J Med. 1959 Jun;26(6):869-82. doi: 10.1016/0002-9343(59)90209-8. PMID: 13649713. 

3.  Thongprayoon C, Petnak T, Kaewput W, et al. Hospitalizations for Acute Salicylate Intoxication in the United States. J Clin Med. 2020;9(8):2638. Published 2020 Aug 14. doi:10.3390/jcm9082638

Tuesday, October 19, 2021

Albumin and anion gap

 Q: Albumin has a significant (select one) 

 A) net negative charge 

B) net positive charge


Answer: A

The objective of this question is to lead readers toward the importance of albumin in an-ion gap calculation. ICU patients tend to have low albumin for various reasons and it can affect the calculation of an-ion gap.

To maintain hemostasis, the human body exists in balance: 

 Total serum cations = Total serum anions 

 In other words:

   Na + All unmeasured cations = Cl + HCO3 + All unmeasured anions 

With a negative charge, albumin is a significant role-player in this equation. The formula to adjust the anion gap is 

Corrected serum anion gap = (Serum anion gap measured) + (2.5 x [4.5 - Observed serum albumin]) 

 Simply, the anion gap falls by approximately 2.5 mEq/L for every 1 g/dL below normal (4.5 g/L) of serum albumin concentration.


#acid-base



Reference:

Feldman M, Soni N, Dickson B. Influence of hypoalbuminemia or hyperalbuminemia on the serum anion gap. J Lab Clin Med 2005; 146:317.

Monday, October 18, 2021

encephalomyelitis due to Melioidosis

 Q; 44 years old male who recently returned from a trip visiting northern Australia is now admitted with sepsis. Subsequent workup led to the diagnosis of Melioidosis. What are the characteristic neurological features of encephalomyelitis due to Melioidosis? 

 Answer: Melioidosis is an infective disease by the facultative intracellular gram-negative bacterium, Burkholderia pseudomallei. It is found in soil and fresh surface water and is more prevalent in wet seasons. It is endemic in Southeast Asia including Indian sub-continent, Thailand, Malaysia, Singapore, Australia, and China. Northeastern Thailand and northern Australia are known as "hyperendemic" areas. 

Encephalomyelitis in melioidosis has characteristic features with consciousness normal or near-normal. It primarily involves the brainstem with possible abscess formation. It causes unilateral upper motor neuron limb weakness, cerebellar signs, cranial nerve palsies, and/or flaccid paraparesis alone. Cranial nerves VI, VII are mostly involved as well as bulbar palsy. 

Resistance to many common antibiotics is common for Burkholderia pseudomallei. Usually, meropenpem is considered the antibiotic of choice.

#ID

#neurolgy


References:

1. Cheng AC, Currie BJ. Melioidosis: epidemiology, pathophysiology, and management. Clin Microbiol Rev 2005; 18:383.

2. Currie BJ, Dance DA, Cheng AC. The global distribution of Burkholderia pseudomallei and melioidosis: an update. Trans R Soc Trop Med Hyg 2008; 102 Suppl 1:S1.

3. Currie BJ, Fisher DA, Howard DM, et al. The epidemiology of melioidosis in Australia and Papua New Guinea. Acta Trop 2000; 74:121. 

4. Woods ML 2nd, Currie BJ, Howard DM, et al. Neurological melioidosis: seven cases from the Northern Territory of Australia. Clin Infect Dis 1992; 15:163. 

5. Currie BJ, Fisher DA, Howard DM, Burrow JN. Neurological melioidosis. Acta Trop 2000; 74:145.

Sunday, October 17, 2021

Dig and weight

 Q; Digoxin should be given based on (select one)

A) adjusted body weight

B) actual body weight

C) ideal body weight


Answer: C

There are four major determinants of digoxin dosing and subsequently its toxicity 

  • kidney function 
  • ideal body weight
  • drug interaction
  • electrolyte balance
The objective of this question is to highlight the narrow therapeutic index of digoxin. 

There are other factors that may contribute to "dig toxicity". Digoxin should be avoided in patients with various atrioventricular (AV) blocks. Electrolyte imbalance such as hypokalemia, hypomagnesemia, and hypercalcemia increases the risk of digoxin-related arrhythmia. ​

Hypothyroidism is also considered a risk factor for digoxin toxicity..

#pharmacology
#cardiology


References:

1. DiDomenico RJ, Bress AP, Na-Thalang K, et al. Use of a simplified nomogram to individualize digoxin dosing versus standard dosing practices in patients with heart failure. Pharmacotherapy 2014; 34:1121. 

2. Bauman JL, DiDomenico RJ, Viana M, Fitch M. A method of determining the dose of digoxin for heart failure in the modern era. Arch Intern Med 2006; 166:2539.

Saturday, October 16, 2021

Ascites in hepatorenal syndrome

Q:  Resistant ascites is a feature of (select one) 

A) Type 1 hepatorenal syndrome 

B) Type 2 hepatorenal syndrome


Answer: B

Hepatorenal syndrome is divided into two types depending on the severity of the decline

  • Type 1 is more life-threatening and is characterized by a rapid decline of renal function. It is defined by at least a twofold increase in serum creatinine within 2 weeks. Although patients are non-oliguric in the early phase of the disease oliguria becomes universal later in the course.
  • Type 2 is less severe and the major feature is the resistant ascites unresponsive to diuretics.
#nephrology
#hepatology


References:

1. Ginès P, Schrier RW. Renal failure in cirrhosis. N Engl J Med 2009; 361:1279.

2. Arroyo V, Ginès P, Gerbes AL, et al. Definition and diagnostic criteria of refractory ascites and hepatorenal syndrome in cirrhosis. International Ascites Club. Hepatology 1996; 23:164. 

3. Salerno F, Gerbes A, Ginès P, et al. Diagnosis, prevention and treatment of hepatorenal syndrome in cirrhosis. Gut 2007; 56:1310.

Friday, October 15, 2021

TMP-SMX and PCP

 Q: If Trimethoprim-sulfamethoxazole (TMP-SMX) is used for the treatment of Pneumocystis pneumonia in AIDS patients, which of the following is recommended to be used as an adjuvant treatment? (select one) 

 A) folic acid 

B) folinic acid

C) any of the above 

D) none of the above 


 Answer: D

It is recommended to use folate as an adjuvant treatment while TMP-SMX is in use particularly in prolonged use. TMP-SMX is popularly known with its trade name Bactrim. Trimethoprim (TMP) inhibits human dihydrofolate reductase. In prolong use or with its use in folate deficiency it may lead to megaloblastic changes i.e. macrocytic anemia, thrombocytopenia, and/or leukopenia. 

Folinic acid, also known as leucovorin can be used instead of folic acid. 

Said that this adjuvant treatment should not be used in few specific conditions or one should be preferred over the other like:
  • In AIDS patients who develop pneumocystis pneumonia, none should be used as it may lead to treatment failure. 
  • If a patient is pregnant and develops pneumocystis pneumonia, folic acid should be added as the risk of neural tube defects would be high. 
  • In patients with toxoplasmosis, leucovorin (folinic acid) is preferred as parasites can metabolize folic acid but can't metabolize folinic acid.

#pharmacology


References:

1. Ho JM, Juurlink DN. Considerations when prescribing trimethoprim-sulfamethoxazole. CMAJ 2011; 183:1851. 

2. Safrin S, Lee BL, Sande MA. Adjunctive folinic acid with trimethoprim-sulfamethoxazole for Pneumocystis carinii pneumonia in AIDS patients is associated with an increased risk of therapeutic failure and death. J Infect Dis 1994; 170:912.

Thursday, October 14, 2021

Negative APR

 Q: Which of the following is the 'negative' acute phase reactant (APR)? 

A) Interleukin (IL)-6 

B) IL-1 beta 

C) Tumor necrosis factor (TNF)-alpha 

D) Interferon gamma 

E) Albumin


Answer: E

During any inflammation such as infection, trauma, tumor, infarction, or autoimmune disease - macrophages, monocytes, and other cells increases the APR production. This occurs mostly in the hepatocytes and subsequently decreases the production of albumin. 

The low level of albumin during such an inflammatory state is called "negative APR". The other negative APR is Transferrin.

#inflammation


References:

1. Loyer P, Ilyin G, Abdel Razzak Z, et al. Interleukin 4 inhibits the production of some acute-phase proteins by human hepatocytes in primary culture. FEBS Lett 1993; 336:215. 

2. Jain S, Gautam V, Naseem S. Acute-phase proteins: As diagnostic tool. J Pharm Bioallied Sci. 2011;3(1):118-127. doi:10.4103/0975-7406.76489

Wednesday, October 13, 2021

Pleural effusion characterization

 Q: All of the following almost always cause transductive pleural effusion EXCEPT

A) Heart failure

B) Hepatic hydrothorax

C) Nephrotic syndrome 

D) Peritoneal dialysis

E) Pulmonary embolism


Answer: E

Characteristic of pleural fluid is one of the basics which guide towards establishing the diagnosis. Few conditions are known to cause ALMOST ALWAYS transudative pleural effusion. It includes:

  • CSF leak into pleural space (after trauma or spinal surgery or VP shunt) 
  • Heart failure
  • Hepatic hydrothorax
  • Hypoalbuminemia
  •  Misplaced central line 
  • Nephrotic syndrome
  • Peritoneal dialysis 
  • Urinothorax

Few conditions usually cause exudative pleural effusion but transductive is possible:
  • Amyloidosis
  • Chylothorax
  • Constrictive pericarditis
  • Hypothyroidism
  • Malignancy
  • Pulmonary embolism
  • Late Sarcoidosis
  • Superior vena caval syndrome

#procedures
#pulmonary 


References:

1. Porcel JM, Azzopardi M, Koegelenberg CF, Maldonado F, Rahman NM, Lee YC. The diagnosis of pleural effusions. Expert Rev Respir Med. 2015;9(6):801-815. doi:10.1586/17476348.2015.1098535

2. Saguil A, Wyrick K, Hallgren J. Diagnostic approach to pleural effusion. Am Fam Physician. 2014;90(2):99-104.

Tuesday, October 12, 2021

TdP

 Q: 47 years old male who is in ICU for severe psychosis went into Torsades De Pointes (TdP) with hemodynamic instability. Which of the following is the first line of treatment? (select one) 

 A) Intravenous (IV) Magnesium (Mg) 

B) Overdrive pacing 

 

Answer: A

 IV Mg continues to be the first line of treatment in TdP. In hemodynamically unstable patients, the dose is 1 to 2 gram IV bolus which can be given up to 4 grams. It can be continued as an infusion. Overdrive pacing can be used at a rate of about 100 beats per minute if IV Mg fails to show any effect. 

Isoproterenol can also be used. Alkalinization of the plasma with sodium bicarbonate is recommended if TdP is due to quinidine. 

Patient in the above question was admitted to ICU with severe psychosis. It is probable that TdP is due to anti-psychotic. Discontinuation of the offending drug is the ultimate treatment.

#cardiology

#hemodynamic


References:

1. Passman R, Kadish A. Polymorphic ventricular tachycardia, long Q-T syndrome, and torsades de pointes. Med Clin North Am 2001; 85:321. 

2. Khan IA. Long QT syndrome: diagnosis and management. Am Heart J 2002; 143:7. 

3. Tzivoni D, Banai S, Schuger C, et al. Treatment of torsade de pointes with magnesium sulfate. Circulation 1988; 77:392.

4. Gowda RM, Khan IA, Wilbur SL, Vasavada BC, Sacchi TJ. Torsade de pointes: the clinical considerations. Int J Cardiol. 2004;96(1):1-6. doi:10.1016/j.ijcard.2003.04.055

Monday, October 11, 2021

dialysate solution

 Q: Which of the following electrolyte is NOT part of dialysate solution? 

 A) sodium 

B) potassium 

C) calcium 

D) phosphate

E) chloride


Answer: D

Dialysate solution universally contains six electrolytes in which sodium, calcium, magnesium, and chloride are present as equivalent in extracellular fluid. Potassium and bicarbonate are used as buffers. Glucose is the seventh component which is almost always included, Nephrologist may decide to hold it in case of severe hyperglycemia though its inclusion is recommended despite hyperglycemia to avoid hypoglycemia which can be detrimental without warning. 

Dialysate solution is an isotonic solution with an osmolality of 300 ± 20 milliosmoles per liter (mOsm/L). The goal is to keep the osmolality of dialysate close to plasma osmolality to avoid red blood cell hemolysis and/or crenation. 

Hyperphosphatemia is common in patients with renal failure and can be a marker of disease severity. Although hypophosphatemia is common in patients who undergo Continuous Renal Replacement Therapy (CRRT), it is usually corrected by supplementation. 

#nephrology


References: 

1. Desai N. (2015). Basics of base in hemodialysis solution: Dialysate buffer production, delivery and decontamination. Indian journal of nephrology, 25(4), 189–193. https://doi.org/10.4103/0971-4065.147369 

2. Song YH, Seo EH, Yoo YS, Jo YI. Phosphate supplementation for hypophosphatemia during continuous renal replacement therapy in adults. Ren Fail. 2019;41(1):72-79. doi:10.1080/0886022X.2018.1561374 

3.  Jung, S. Y., et. al (2018). Phosphate is a potential biomarker of disease severity and predicts adverse outcomes in acute kidney injury patients undergoing continuous renal replacement therapy. PloS one, 13(2), e0191290. https://doi.org/10.1371/journal.pone.0191290

Sunday, October 10, 2021

Linezolid side-effects

 Q: Thrombocytopenia due to Linezolid is more common in? (select one) 

A) Liver Insufficiency 

B) Renal insufficiency 


 Answer:

 Linezolid-induced thrombocytopenia is the least bothered entity as it is usually resolved with the discontinuation of the drug. Some of the other side-effects can be irreversible and may actually prove fatal like peripheral neuropathy, lactic acidosis, and ocular toxicity. Another concern with its use in ICU is development of serotonin syndrome. 

Thrombocytopenia is more common in patients with end-stage kidney disease (ESRD).

#pharmacology

#ID


References:

1. Kishor K, Dhasmana N, Kamble SS, Sahu RK. Linezolid Induced Adverse Drug Reactions - An Update. Curr Drug Metab. 2015;16(7):553-9. doi: 10.2174/1389200216666151001121004. PMID: 26424176. 

2. Hashemian SMR, Farhadi T, Ganjparvar M. Linezolid: a review of its properties, function, and use in critical care. Drug Des Devel Ther. 2018;12:1759-1767. Published 2018 Jun 18. doi:10.2147/DDDT.S164515 

3. Wu VC, Wang YT, Wang CY, et al. High frequency of linezolid-associated thrombocytopenia and anemia among patients with end-stage renal disease. Clin Infect Dis 2006; 42:66. 

4. Lawrence KR, Adra M, Gillman PK. Serotonin toxicity associated with the use of linezolid: a review of postmarketing data. Clin Infect Dis 2006; 42:1578.

Saturday, October 9, 2021

Antibiotics in Tetanus

 Q: 47 Years old diabetic male who was involved in a motor vehicle accident (MVA) a week ago presented with generalized tonic contractions of skeletal muscles. With loud noise in ED, patient was found to trigger stiff neck, opisthotonus, risus sardonicus, clench fisting, arching the back, and flexing of arms. Which of the following antibiotics is preferred along with neutralization of the toxin and symptomatic treatment?  

A) Metronidazole 

B) Macrolides 

C) Clindamycin 

D) Vancomycin 

E) Chloramphenicol


Answer: A

A recent history of MVA in a diabetic male with generalized muscle spasms is classic of tetanus. Antibiotics play an adjuvant role in the treatment of tetanus. The mainstay of treatment is wound management (halting of the toxin), neutralization of the toxin, and symptomatic treatment with benzodiazepines. If a patient requires intubation, propofol, dexmedetomidine, atropine, and neuromuscular blockade may be required. Epidural bupivacaine is also helpful. Metronidazole and penicillin G are the two most effective treatments though the former is found to be more efficacious. 

Other antibiotics (choices B to E) have not been studied well though found to be effective in vitro. Although trimethoprim-sulfamethoxazole has been suggested as a treatment, the resistance is almost universal.

#toxicology

#ID


References:

1. Ahmadsyah I, Salim A. Treatment of tetanus: an open study to compare the efficacy of procaine penicillin and metronidazole. Br Med J (Clin Res Ed) 1985; 291:648. 

2. Hassel B. Tetanus: pathophysiology, treatment, and the possibility of using botulinum toxin against tetanus-induced rigidity and spasms. Toxins (Basel). 2013;5(1):73-83. Published 2013 Jan 8. doi:10.3390/toxins5010073

Friday, October 8, 2021

Triple-H therapy

 Q: "Triple-H Therapy" continues to be a mainstay of treatment to prevent cerebral ischemia (vasospasm) after subarachnoid hemorrhage?

A) True

B) False


Answer: B

For a long period of time 

  • Hypervolemia 
  • Hemodilution, and 
  • Hypertension
popularly known as Triple H therapy continue to be the mainstay preventive measure to prevent cerebral ischemia from vasospasm. In the last few years, it has been determined that hypervolemia is not helpful, rather harmful in this matter. 

For hypotension, pressors can be used, and if needed inotropes can be added.

#neurology


References:

1. Francoeur CL, Mayer SA. Management of delayed cerebral ischemia after subarachnoid hemorrhage. Crit Care 2016; 20:277.

2. Muench E, Horn P, Bauhuf C, et al. Effects of hypervolemia and hypertension on regional cerebral blood flow, intracranial pressure, and brain tissue oxygenation after subarachnoid hemorrhage. Crit Care Med 2007; 35:1844.

3. Dankbaar, J. W., Slooter, A. J., Rinkel, G. J., & Schaaf, I. C. (2010). Effect of different components of triple-H therapy on cerebral perfusion in patients with aneurysmal subarachnoid haemorrhage: a systematic review. Critical care (London, England), 14(1), R23. https://doi.org/10.1186/cc8886

Thursday, October 7, 2021

DVTs in PICCs

Q: Which of the following group has a higher risk of Peripherally Inserted Central Catheter (PICC) related Deep Venous Thrombosis (DVT)? (select one) 

A) Cancer patients 

B) Critically ill patients 


Answer:

In the last few years, PICCs have been extremely popular in hospitals. There is an increased tendency to insert PICC during hospitalization to avoid the need for intravenous (IV) catheters. 

It should be reminded that PICCs are not very safe as well. In fact, they carry a higher risk of DVTs. ICU patients with PICCs have almost double the risk of developing DVTs than patients who have Central Venous Cathers (CVCs) inserted in ICU. 

The risk of DVT in ICU patients from PICC continues to be doubled than floor/ward patients and patients who have PICCs inserted for long-term chemotherapy.

#procedure

#hematology


References:

1. Winters JP, Callas PW, Cushman M, et al. Central venous catheters and upper extremity deep vein thrombosis in medical inpatients: the Medical Inpatients and Thrombosis (MITH) Study. J Thromb Haemost 2015; 13:2155.

2. Chopra V, Anand S, Hickner A, et al. Risk of venous thromboembolism associated with peripherally inserted central catheters: a systematic review and meta-analysis. Lancet 2013; 382:311.

Wednesday, October 6, 2021

Post-partum psychosis

 Q: 28 years old female with post-partum severe unipolar depression is admitted to ICU with severe psychosis requiring restraints to prevent harm. What advantage Aripiprazole has over other antipsychotics in this situation? 

 Answer: There is no hard and fast rule for choice of anti-psychotic in post-partum unipolar severe depression associated with psychosis. Aripiprazole is usually considered the first choice as it can be given as a disintegrating tablet or oral solution. Many of these patients may not allow the insertion of "IV" or may harm themselves by pulling their intravenous (IV) line. The dose is 10-15 mg and can be given every 2 hours, though it is not preferred to go beyond the total dose of 30 mg over the 24 hours period. The patient usually calms down with the first couple of doses. The peak plasma concentration occurs within 3-5 hours. Aripiprazole is less sedative in comparison to other antipsychotics, causes minimal prolongation of QTc interval and/or orthostatic hypotension. 

Olanzapine is another good choice though it has decreased clearance in females and in patients who are non-smokers.

#psychiatry

#Ob-Gyn


Further readings:

1. Osborne LM. Recognizing and Managing Postpartum Psychosis: A Clinical Guide for Obstetric Providers. Obstet Gynecol Clin North Am. 2018;45(3):455-468. doi:10.1016/j.ogc.2018.04.005 

2. Sit D, Rothschild AJ, Wisner KL. A review of postpartum psychosis. J Womens Health (Larchmt). 2006;15(4):352-368. doi:10.1089/jwh.2006.15.352

Tuesday, October 5, 2021

Pharmacotherapics in ECMO patients

 Q: What is the caveat of using Echinocandins in a patient who is on extracorporeal membrane oxygenation (ECMO)? 

 Answer: subtherapeutic plasma levels 

Although the example of Echinocadins i.e, caspofungin, micafungin, and anidulafungin has been used in this question, the objective is to introduce the caveat, limitations, and need of vigilance to watch the pharmacotherapeutic level of many drugs in patients who are on ECMO. Many drugs may get sequestered in the ECMO circuit and may cause subtherapeutic plasma levels.  

The service of a clinical pharmacist should be sought and plasma levels should be monitored for important drugs.

#pharmacology


References:

1. Cheng V, Abdul-Aziz MH, Roberts JA, Shekar K. Optimising drug dosing in patients receiving extracorporeal membrane oxygenation. J Thorac Dis. 2018;10(Suppl 5):S629-S641. doi:10.21037/jtd.2017.09.154 

2. Spriet I, Annaert P, Meersseman P, et al. Pharmacokinetics of caspofungin and voriconazole in critically ill patients during extracorporeal membrane oxygenation. J Antimicrob Chemother 2009; 63:767.

Monday, October 4, 2021

Free Magnesium

 Q: What is the 'rule of thumb' for conversion between plasma and free magnesium?

Answer: Multiply by 0.7

Only 70 percent of the Magnesium in plasma is in free form. Said that this applies only in the normal situations. This value probably changes in ICU where gastrointestinal and/or renal losses are common. 

It may be helpful to distinguish between GI and renal loss for persistent hypomagnesemia in ICU patients. 24-hour urinary magnesium excretion should not be more than 10 to 30 mg with normal renal function. 

#electrolytes

#nephrology


References:

1. Jahnen-Dechent W, Ketteler M. Magnesium basics. Clin Kidney J. 2012;5(Suppl 1):i3-i14. doi:10.1093/ndtplus/sfr163

2. Fox CH, Timm EA Jr, Smith SJ, Touyz RM, Bush EG, Wallace PK. A method for measuring intracellular free magnesium concentration in platelets using flow cytometry. Magnes Res. 2007 Sep;20(3):200-7. PMID: 17972463.

Sunday, October 3, 2021

Air embolism in surgeries

 Q: Why neurosurgical and ENT procedures are at higher risk for air embolism? 

 Answer: Because brain and head lies superior to the heart

The pressure gradient in body parts above the heart is higher than the central venous pressure (CVP) causing negative venous pressure relative to the atmosphere. Moreover, many times procedures in these areas are performed in the Fowler’s position. This allows air to easily sucked into the circulation while vessels are dissected and open to the atmosphere during the procedure.

#surgical-critical-care


References:

1. Gale T, Leslie K. Anaesthesia for neurosurgery in the sitting position. J Clin Neurosci 2004; 11:693. 

2. Wong AY, Irwin MG. Large venous air embolism in the sitting position despite monitoring with transoesophageal echocardiography. Anaesthesia 2005; 60:811.

Saturday, October 2, 2021

Infectious thyroiditis

Q: Pain in acute infectious thyroiditis is usually? (select one) 

A) localized in neck 
B) generalized over neck


Answer: A

Infectious thyroiditis usually occurs in immunocompromised patients. It can occur due to bacteremia or due to local extension. Abscess formation is common and requires urgent attention. Clinically it presents as sudden unilateral neck tenderness. Fever and chills are universal. Unilateral fluctuant neck mass should be considered as an abscess unless proved otherwise. Interestingly though signs of thyrotoxicosis may be present but thyroid function usually stays normal. 

Workup requires an ultrasound and fine-needle aspiration biopsy. Treatment is drainage of abscess and broad spectrum antibiotic.


#ID
#surgical-critical-care
#endocrinology


References:

1. Paes JE, Burman KD, Cohen J, et al. Acute bacterial suppurative thyroiditis: a clinical review and expert opinion. Thyroid 2010; 20:247. 

2. Shah SS, Baum SG. Diagnosis and Management of Infectious Thyroiditis. Curr Infect Dis Rep. 2000 Apr;2(2):147-153. doi: 10.1007/s11908-000-0027-7. PMID: 11095850. 

3. McLaughlin SA, Smith SL, Meek SE. Acute suppurative thyroiditis caused by Pasteurella multocida and associated with thyrotoxicosis. Thyroid 2006; 16:307.

Friday, October 1, 2021

TM

 Q: Transverse myelitis (TM) usually affects? (select one)

A) thoracic cord 

B) lumbar cord 


 Answer: A

Transverse myelitis is a segmental spinal cord acute inflammation. Although described as idiopathic and/or an autoimmune process, it can be associated with preceding infection, multiple sclerosis (MS), or connective tissue diseases like SLE, sjögren's syndrome, scleroderma, antiphospholipid antibody syndrome, ankylosing spondylitis, and rheumatoid arthritis. It usually strikes limited segments in the thoracic cord. Symptoms progressed rapidly with leg weakness. It can also cause autonomic dysfunction with bowel and bladder incontinence.  

Treatment includes steroids, immunosuppressives, and immunomodulators.

#neurology


References:

1. Brinar VV, Habek M, Brinar M, et al. The differential diagnosis of acute transverse myelitis. Clin Neurol Neurosurg 2006; 108:278.

2. West TW. Transverse myelitis--a review of the presentation, diagnosis, and initial management. Discov Med. 2013 Oct;16(88):167-77. PMID: 24099672.

3. Borchers AT, Gershwin ME. Transverse myelitis. Autoimmun Rev. 2012 Jan;11(3):231-48. doi: 10.1016/j.autrev.2011.05.018. Epub 2011 May 18. PMID: 21621005.

Thursday, September 30, 2021

difference between trapped and entrapped lungs

 Q: What's the difference between a trapped and an entrapped lung?

Answer: Both trapped and entrapped lungs refer to the condition where lungs do not expand after drainage of the pleural cavity. It can be occupied by effusion, air, or mass. By definition trapped lung refers only to the pleural causes and entrapped lung refers to both pleural and non-pleural causes. Pleural causes are mostly due to adherence to the chest wall due to inflammation. Examples of non-pleural causes are endobronchial obstruction or any interstitial disease. 

Most patients/ with a trapped lung usually have a transudative effusion. An entrapped lung mostly results in an exudative effusion.

#pulmonary


References:

1. John T. Huggins,Fabien Maldonado,Amit Chopra,Najib Rahman,Richard Light, Unexpandable lung from pleural disease : Respirology Volume23, Issue2 February 2018 Pages 160-167 https://doi.org/10.1111/resp.13199 
 Url: https://onlinelibrary.wiley.com/doi/full/10.1111/resp.13199 (last accessed September 29, 2021)

2. Huggins JT, Doelken P, Sahn SA. The unexpandable lung. F1000 Med Rep. 2010;2:77. Published 2010 Oct 21. doi:10.3410/M2-77

Wednesday, September 29, 2021

Escape of Florinef

 Q: What is an "escape phenomenon" of Fludrocortisone?

Answer: Fludrocortisone is a synthetic mineralocorticoid that works by increasing renal sodium and water reabsorption. The overall effect is intravascular volume expansion and increases blood pressure. In prolong use over few weeks, patients develop an "escape phenomenon", which means that overall blood volume hemostasis (balance) goes back to pre-treatment level between intra and extravascular compartments - but its pressor effect stays as it is. This is due to increased peripheral vascular resistance.

#hemodynamics


Reference:

Chobanian AV, Volicer L, Tifft CP, et al. Mineralocorticoid-induced hypertension in patients with orthostatic hypotension. N Engl J Med 1979; 301:68.

Tuesday, September 28, 2021

CRRT and calories

  Q: Continuous renal replacement therapy (CRRT) can be a source of calories to patients in ICU?

A) True

B) False


Answer: A

As a standard of practice, a solution with a concentration of 100 mg/dL of glucose is used during CRRT. Moreover, citrate solution is also added as a normal practice. 

There is a net calorie deliverance of 512 kcal per day on average by the use of glucose and citrate solutions during CRRT. This should be taken into account while calculating patients' total calorie count for the day.

#nephrology

#endocrinology


References:

1.  New AM, Nystrom EM, Frazee E, Dillon JJ, Kashani KB, Miles JM. Continuous renal replacement therapy: a potential source of calories in the critically ill. Am J Clin Nutr. 2017;105(6):1559-1563. doi:10.3945/ajcn.116.139014

Monday, September 27, 2021

sildenafil and left ventricular (LV) contractility

 Q: Sildenafil? (select one) 

A) increases the left ventricular (LV) contractility 

B) reduces the left ventricular (LV) contractility


Answer: B

Sildenafil is a selective type 5 phosphodiesterase (PDE-5) inhibitor. Although its clinical efficacy has been established in Erectile Dysfunction and pulmonary hypertension, so far it has not shown any major benefit in congestive heart failure (CHF). It has three main effects in hemodynamic. 
  • It decreases the pulmonary vascular resistance 
  • It lowers the systemic arterial load 
  • It reduces the left ventricular (LV) contractility
It may improve the peak VO2 in CHF patients with reduced LVEF but no benefit in patients with preserved ejection fraction.

#hemodynamic
#cardiology
#pulmonary
#pharmacology


References:

1. Borlaug BA, Lewis GD, McNulty SE, et al. Effects of sildenafil on ventricular and vascular function in heart failure with preserved ejection fraction. Circ Heart Fail 2015; 8:533. 

2. Zhuang XD, Long M, Li F, et al. PDE5 inhibitor sildenafil in the treatment of heart failure: a meta-analysis of randomized controlled trials. Int J Cardiol 2014; 172:581.

post-pericardiotomy syndrome

Q: In cardiac surgery which of the following has the LEAST occurrence in post-pericardiotomy syndrome? 

A) Pericardial effusion 
B) Cardiac tamponade 
C) Elevated C-reactive protein 
D) Pericardial rub 
E) ECG changes 


Answer: B

Although some level of pericardial effusion occurs in almost 90 percent of the patients after cardiac surgery, overt cardiac tamponade occurs in only about 2 percent of the cases. 

Another interesting phenomenon i.e., the classic ST elevation in all leads of EKG can be noticed only in one-fourth of the patients but high CRP can be obtained in three-fourth of the patients. 

Other common findings are pleuritic chest pain, fever, and pericardial rub.

#surgical-critical-care
#cardiology


Reference:

Imazio M, Brucato A, Rovere ME, et al. Contemporary features, risk factors, and prognosis of the post-pericardiotomy syndrome. Am J Cardiol 2011; 108:1183.

Sunday, September 26, 2021

second IVIG in GBS

Q: For patients with refractory Guillain-Barré syndrome (GBS) who do not respond to the first round of Intravenous immunoglobulin (IVIG), the second course of infusion can be given as "nothing to lose"? 

A) Yes 
B) No


Answer: B

Giving a second course of IVIG to patients who stayed in refractory GBS may harm the patient. It increases thromboembolic complications. There is no added benefit. A recent study published by the Dutch GBS study group showed no benefit, rather harm. 

It was a randomized, double-blind, placebo-controlled trial. Patients were randomly assigned after eligibility for poor prognosis through modified Erasmus Guillain-Barré syndrome Outcome Score. The primary outcome measure was the Guillain-Barré syndrome disability score after 4 weeks. The study spanned over 8 years (Feb 2010 - June 2018). Out of total 337 patients, 93 patients with poor prognosis were included in the modified intention-to-treat analysis: 49 received second course of IVIG, and 44 received placebo. Patients in the treatment group had more serious adverse events (35% vs 16% in the first 30 days), including thromboembolic events. Four patients died in the intervention group (13-24 weeks after randomization).

#neurology


Reference:

Walgaard C, Jacobs BC, Lingsma HF, et al. Second intravenous immunoglobulin dose in patients with Guillain-Barré syndrome with poor prognosis (SID-GBS): a double-blind, randomised, placebo-controlled trial. Lancet Neurol. 2021;20(4):275-283. doi:10.1016/S1474-4422(20)30494-4

Saturday, September 25, 2021

ITP

 Q: Persistent and chronic immune thrombocytopenia is the same thing? (select one)

A) Yes

B) No


Answer: B

It is important to distinguish ITP on the basis of the time period elapsed since diagnosis. This may contribute to the different management of the disease On the basis of time period ITP is divided into three major categories 
  •  Newly diagnosed – Up to 3 months since diagnosis
  •  Persistent – 3-12 months since diagnosis 
  •  Chronic – More than 12 months since diagnosis
Another laboratory clue is to watch changes in other lineages of blood cells, such as WBC and RBC. Any such association excludes the diagnosis of ITP, and a patient may have a new/different pathology.

#hematology


Reference:

Onisâi M, Vlădăreanu AM, Spînu A, Găman M, Bumbea H. Idiopathic thrombocytopenic purpura (ITP) - new era for an old disease. Rom J Intern Med. 2019 Dec 1;57(4):273-283. doi: 10.2478/rjim-2019-0014. PMID: 31199777.

Friday, September 24, 2021

SOB after travel to SE Asia

 Q: 22 years old male born and raised in the United States recently returned after an eight weeks summer trip from Pakistan. Patient has been brought to ED with shortness of breath. CT-chest showed severe pneumonitis. Patient is reported to comply with all required vaccinations and medications recommended for travel to the Southeast Asia region. Which of the following prophylaxis could be responsible for his symptoms?

A) Doxycycline

B) Mefloquine

C) Hepatitis A vaccine

D) Hepatitis B vaccine

E) Azithromycin  


Answer: B

Malarial prophylaxis is highly recommended while traveling to endemic areas known for malaria such as southeast Asia. Mefloquine is one of the most commonly prescribed malarial prophylaxis. A dreaded complication though rare is Mefloquine-induced pneumonitis which fortunately responds to corticosteroids, and gets resolved with the discontinuation of mefloquine. 

Also, caution should be taken in patients while prescribing Mefloquine with cardiac conduction abnormalities and a history of neurologic and/or psychiatric disorders. It may lead to encephalopathy, sleep disturbances with particular reference to strange dreams. 

Mefloquine is usually started 2 weeks prior to the departure date. Symptoms should be watched closely during this period.

#ID
#pulmonary
#neurology
#travel-medicine


References:

1. Chen LH, Wilson ME, Schlagenhauf P. Controversies and misconceptions in malaria chemoprophylaxis for travelers. JAMA 2007; 297:2251. 

2. Meier CR, Wilcock K, Jick SS. The risk of severe depression, psychosis or panic attacks with prophylactic antimalarials. Drug Saf 2004; 27:203. 

3. Katsenos S, Psathakis K, Nikolopoulou MI, Constantopoulos SH. Mefloquine-induced eosinophilic pneumonia. Pharmacotherapy 2007; 27:1767. 

4. Soentjens P, Delanote M, Van Gompel A. Mefloquine-induced pneumonitis. J Travel Med 2006; 13:172.