pseudo pulmonary embolus

Q: What is pseudo-pulmonary embolus syndrome?

Answer: Pseudo-pulmonary embolism is an umbrella term of clinical syndrome, where symptoms like acute pulmonary embolism (PE) occur. It is commonly seen after heparin bolus; many experts consider it a type of Heparin-induced thrombocytopenia (HIT). But it can be seen in other conditions like from tumor burden around pulmonary vessels (reference #2) or in congenital heart diseases (reference #3)

The most common culprits are patients with hemodialysis (HD) who frequently acquire heparin boluses for their dialysis. It occurs shortly after an intravenous heparin bolus and is considered most likely to be one of HIT type II. This is not due to pulmonary embolus but is thought to be due to an endothelial injury, with sudden augmented release of IL-6, von Willebrand factor, and other adhesion molecules, resulting in an acute adult-type respiratory distress syndrome as a result of sudden vascular leak with hypoxia and hypotension.

#pulmonary

#hematology

#nephrology

#oncolgy

#cardiology

References:

1. Hartman V, Malbrain M, Daelemans R, Meersman P, Zachée P. Pseudo-pulmonary embolism as a sign of acute heparin-induced thrombocytopenia in hemodialysis patients: safety of resuming heparin after disappearance of HIT antibodies. Nephron Clin Pract. 2006;104(4):c143-8. doi: 10.1159/000094959. Epub 2006 Aug 10. PMID: 16902310.

2. Salomon O, Leshem Y, Gluck I, Grossman E, Apter S, Konen E. Pseudo pulmonary embolism in cancer patients: a new clinical syndrome. Blood Coagul Fibrinolysis. 2014 Dec;25(8):871-5. doi: 10.1097/MBC.0000000000000174. PMID: 25022841.

3. Cook GJ, Fogelman I. Pseudo pulmonary embolism in complex congenital heart disease. J Nucl Med. 1996 Aug;37(8):1359-61. PMID: 8708773.

Rx of severe postpartum unipolar depression

Q: 27 years old, recently postpartum female is admitted to ICU with severe unipolar depression and suicidal ideation; which of the following is a drug of choice? - select one

A) Brexanolone

B) Zuranolone

C) Fluoxetine

D) Paroxetine

E) Sertraline

Answer: B

Zuranolone is classified as a neuroactive steroid. It provides a rapid response and is usually well tolerated. It is recommended by the practice guidelines from the American College of Obstetricians and Gynecologists. It is given as 50 mg orally each evening for 2 weeks. Another advantage is that it can be combined with other antidepressants. The only care that needs to be taken is administering it with fat-containing food, which facilitates absorption.

Though Brexanolone is also a rapid-acting neuroactive steroid, it requires 60 hours of infusions. It can be used as an alternative to quinolone but should not be given to patients who failed quinolone because it is the same class of drug.

Other choices in the question (Choices C, D, and E) are the second line of drugs, which can be used as maintenance drugs later.

#psychiatry

#ob-gyn

References:

1. The American College of Obstetricians and Gynecologists. Zuranolone for the Treatment of Postpartum Depression. Practice Advisory. August 2023. https://www.acog.org/clinical/clinical-guidance/practice-advisory/articles/2023/08/zuranolone-for-the-treatment-of-postpartum-depression? (Accessed on October 01, 2024).

2. Patterson R, Balan I, Morrow AL, Meltzer-Brody S. Novel neurosteroid therapeutics for post-partum depression: perspectives on clinical trials, program development, active research, and future directions. Neuropsychopharmacology 2024; 49:67.

3. HIGHLIGHTS OF PRESCRIBING INFORMATION FOR ZURANOLONE. Revised 11/2023. https://documents.sage-biogen.com/us/zurzuvae/pi.pdf (Accessed on October 6, 2024).

BBs and HD

Q: 56 years old male is admitted to ICU with his prescribed Beta-Blocker (BB) overdose. Patient is severely hypotensive and bradycardic. A transcutaneous pacemaker is applied. To resolve the overdose, hemodialysis (HD) is suggested. Which of the following BBs may not get removed by HD? - select one

A) Metoprolol

B) Atenolol

C) Nadolol 

D) Sotalol 

E) Acebutolol 

Answer: A

Hemodialysis (HD) can be instituted in extreme BB overdose when all other remedies fail. However, not all B-blockers respond to dialysis.

B-blockers that respond to HD are mostly low protein-binding and water-soluble. Atenolol has been described as the most responsive B-blocker. Nadolol and sotalol are also removed by hemodialysis. Acebutolol is also dialyzable.

B-blockers that do not respond to HD are propranolol, metoprolol, and timolol.

#toxicity

#pharmacology

References:

1. Bouchard J, Shepherd G, Hoffman RS, Gosselin S, Roberts DM, Li Y, Nolin TD, Lavergne V, Ghannoum M; EXTRIP workgroup. Extracorporeal treatment for poisoning to beta-adrenergic antagonists: systematic review and recommendations from the EXTRIP workgroup. Crit Care. 2021 Jun 10;25(1):201. doi: 10.1186/s13054-021-03585-7. PMID: 34112223; PMCID: PMC8194226.

2. Rotella JA, Greene SL, Koutsogiannis Z, Graudins A, Hung Leang Y, Kuan K, Baxter H, Bourke E, Wong A. Treatment for beta-blocker poisoning: a systematic review. Clin Toxicol (Phila). 2020 Oct;58(10):943-983. doi: 10.1080/15563650.2020.1752918. Epub 2020 Apr 20. PMID: 32310006.

3. Khalid MM, Galuska MA, Hamilton RJ. Beta-Blocker Toxicity. [Updated 2023 Jul 28]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK448097/

EtCO2 and bicarb

 Q: During cardiac resuscitation, administration of sodium bicarbonate may cause erroneous ___________ in End-Tidal CO2 (EtCO2)? - select one

A) increase

B) decrease

Answer: A

The use of EtCO2 is on the rise in the ICU for various reasons. It is important to know the confounding factors associated with its administration.

EtCO2 may increase erroneously moments after administration of sodium bicarbonate. This effect is short-lived, though - and if hemodynamics continue to improve, this increase will stay sustained.

#resuscitation

#hemodynamics

Reference:

1. Sandroni C, De Santis P, D'Arrigo S. Capnography during cardiac arrest. Resuscitation 2018; 132:73.

2. Roh YI, Kim HI, Kim SJ, et al. End-tidal carbon dioxide after sodium bicarbonate infusion during mechanical ventilation or ongoing cardiopulmonary resuscitation. Am J Emerg Med 2024; 76:211.

Dunbar syndrome

Q: 49 years old presented to the Emergency room with progressive worsening abdominal pain and weight loss over the last few months. On exam, an abdominal bruit is heard. Patient is sent for CT-Angiography. The radiologist called the report Dunbar syndrome.  

Answer: The exact technical name of Dunbar syndrome is celiac artery compression syndrome, celiac axis syndrome, or median arcuate ligament syndrome. It is a myriad of symptoms due to the compression of the celiac artery by the median arcuate ligament. Classically, it is a triad of

• postprandial abdominal pain
• weight loss
• abdominal brսit

Many times, a diagnosis is one of exclusion. It may require surgical decompression of the celiac axis. It is four times more common in males and often manifests in middle age.

#surgical-critcal-care

#vascular 

References:

1. Dunbar JD, Molnar W, Beman FF, Marable SA. Compression of the celiac trunk and abdominal angina. Am J Roentgenol Radium Ther Nucl Med 1965; 95:731.

2. Iqbal S, Chaudhary M. Median arcuate ligament syndrome (Dunbar syndrome). Cardiovasc Diagn Ther. 2021 Oct;11(5):1172-1176. doi: 10.21037/cdt-20-846. PMID: 34815969; PMCID: PMC8569275.

3. Kim EN, Lamb K, Relles D, et al. Median Arcuate Ligament Syndrome-Review of This Rare Disease. JAMA Surg 2016; 151:471. 

ASA levels and toxicity

Q: Serum salicylate (ASA) concentration tends to ____________ clinical signs? - select one

A) lags

B) precedes

Answer: A

Although it is recommended to repeat serum salicylate concentration every 2-4 hours to avoid missing prolonged or delayed absorption, the serum ASA level usually lags behind the clinical status by many hours, particularly in the early phase. That's why ASA toxicity is a clinical diagnosis, because of history, physical exam, and other lab findings. This is due to a change in the tissue concentration. It takes time for tissue concentration to equilibrate the clinical status.

The clinical implication of the above discordance is enormous. Clinicians may get baffled by the life-threatening effects of salicylate toxicity but a decreasing or near-therapeutic serum ASA levels. A decreasing ASA concentration in a patient with progressively worsening clinical manifestations of ѕаlicуlism, i.e., worsening acidosis or lеthargу indicates altered tissue distribution and more severe disease rather than increased elimination. 

#toxicity

References:

1. Peketi SH, Upadrista PK, Cadet B, Cadet J, Cadet N. Salicylate Poisoning and Rebound Toxicity. Cureus. 2024 May 13;16(5):e60241. doi: 10.7759/cureus.60241. PMID: 38746490; PMCID: PMC11093619.

2. American College of Medical Toxicology. Guidance document: management priorities in salicylate toxicity. J Med Toxicol. 2015 Mar;11(1):149-52. doi: 10.1007/s13181-013-0362-3. PMID: 25715929; PMCID: PMC4371029.

3. Akshintala D, Mendez A, Ikladios OI, Emani VK. Severe salicylate poisoning resistant to conventional management. J Community Hosp Intern Med Perspect. 2018 Dec 11;8(6):373-375. doi: 10.1080/20009666.2018.1551027. PMID: 30559949; PMCID: PMC6292349.

MV and hemodynamic

Q: Which of the following may not be an effect of mechanical ventilation on hemodynamics? - select one

A) Decreased venous return

B) Reduced right ventricular output

C) Reduced left ventricular output

D) Compressed Aortic Valve (AV)

Answer: D

Almost half of the patients (43%) develop hemodynamic instability within one hour of intubation with 

• systolic blood pressure <65 mmHg at least once
• <90 mmHg for >30 minutes
• new or increased need for vasopressors or fluid bolus >15 mL/kg 

It is well known that positive pressure vеոtilatiоn decreases cardiac output, leading to hypotension. It is important to understand all three major mechanisms of action.

1. Decreased venous return: An increase in intrathoracic and right atrial pressure due to positive pressure vеոtilаtiοո reduces the gradient for venous return. This effect is further augmented by higher positive end-expiratory pressure (ΡЕЕР) or intravascular hypovolemia.

2. Reduced right ventricular output – Alveolar inflation during positive pressure vеոtilаtiοո compresses the pulmonary vascular bed. This increases pulmonary vascular resistance and reduces the right ventricular output. This effect can be mitigated by augmenting venous blood volume.

3. Reduced left ventricular output – Increased pulmonary vascular resistance can shift the interventricular septum to the left, impair diastolic filling of the left ventricle, and reduce left ventricular output. An interesting paradox may occur here: In Patients with left ventricular failure, the increased intrathoracic pressure from positive pressure vеntilatiοn may improve left ventricular function by decreasing both venous return and left ventricular afterload.

#hemodynamic

#ventilators

References:

1. Russotto V, Myatra SN, Laffey JG, et al. Intubation Practices and Adverse Peri-intubation Events in Critically Ill Patients From 29 Countries. JAMA 2021; 325:1164.

2. Fougères E, Teboul JL, Richard C, et al. Hemodynamic impact of a positive end-expiratory pressure setting in acute respiratory distress syndrome: importance of the volume status. Crit Care Med 2010; 38:802.

3. Bersten AD, Holt AW, Vedig AE, et al. Treatment of severe cardiogenic pulmonary edema with continuous positive airway pressure delivered by face mask. N Engl J Med 1991; 325:1825.

Varicella and isolation

Q: 34 years old pregnant female is admitted to ICU with active varicella pneumonia. A negative pressure room should be used, and all providers should be required to wear an N95 respirator.

A) True

B) False

Answer: A

Despite vaccination, providers can acquire varicella. Patient requires both airborne and contact precautions. However, staff with evidence of immunity should care for such patients. An N95 respirator mask should be required. All visitors should be considered susceptible and should wear N95.

There is a case report where a provider who never entered the patient's negative pressure isolation room but remained in the outside corridor passing materials in through an open door - and acquired the infection.

For exposed sero-susceptible patients, isolation and all precautions should continue from the 8th day after the first exposure to the 21st day after the date of the last exposure. ID service and hospital's infectious control committee should be consulted.

#ID

References:

1. Advisory Committee on Immunization Practices, Centers for Disease Control and Prevention (CDC). Immunization of health-care personnel: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep 2011; 60:1.

2. Tang JW, Eames I, Li Y, et al. Door-opening motion can potentially lead to a transient breakdown in negative-pressure isolation conditions: the importance of vorticity and buoyancy airflows. J Hosp Infect 2005; 61:283.

Nijmegen score

Q: 24 years old male who had a documented diagnosis of long-COVID is admitted to ICU with chest pain and respiratory distress. After his workup, he has been diagnosed with hуреrvеոtilаtiоո syndrome. Clinicians used Nijmegen score to diagnose hуреrvеոtilаtiоո syndrome. All of the following are part of this score EXCEPT? - select one

A) Chest pain

B) Blurred vision

C) Constipation

D) Shortness of breath

E) Unable to breathe deeply

Answer: C

Although hуреrvеոtilаtiоո syndrome remained a controversial clinical etiology, many patients after COVID-19, particularly those who acquired long-COVID, are presenting with such symptoms. Nijmegen score (invented before the COVID pandemic) is used along with hуреrvеոtilation challenge and cardiopulmonary ехеrϲisе testing to establish the diagnosis of hуреrvеոtilаtiоո syndrome. The following are the components of the Nijmegen score. Each element can be graded from 0 to 4. A score above 23 suggests a positive diagnosis of hyperventilation syndrome. 

• Chest pain
• Feeling tense
• Blurred vision
• Dizzy spells
• Feeling confused
• Faster or deeper breathing
• Short of breath
• Tight feelings in chest
• Bloated feeling in stomach
• Tingling fingers
• Unable to breathe deeply
• Stiff fingers or arms
• Tight feelings around mouth
• Cold hands or feet
• Palpitations
• Feeling of anxiety 

#pulmonary

#COVID

References:

1. van Dixhoorn J, Folgering H. The Nijmegen Questionnaire and dysfunctional breathing. ERJ Open Res 2015; 1.

2. Taverne J, Salvator H, Leboulch C, et al. High incidence of hyperventilation syndrome after COVID-19. J Thorac Dis 2021; 13:3918.

Pregnancy and PICC

Q: 28 years old female required to have peripherally inserted central catheter (PICC) for long-term antibiotics. Pregnancy increases the risk of deep venous thrombosis (DVT).

A) True

B) False

  

Answer: A

Any physiologic, unphysiological, or iatrogenic hormonal change in the body may increase the risk of DVT, including pregnancy. This also includes non-catheter-related upper extremity DVΤ. 

A similar risk exists for oral contraceptives, particularly in patients with prothrombotic mutations, such as prothrombin 20210 or factor V Leiden. This risk remains relatively high in patients undergoing ovulation induction and in vitro fertilization.

#ob-gyn

#hematology

References:

1. Jacques L, Foeller M, Farez R, et al. Safety of peripherally inserted central catheters during pregnancy: a retrospective study. J Matern Fetal Neonatal Med 2018; 31:1166.

2. Vayá A, Mira Y, Mateo J, et al. Prothrombin G20210A mutation and oral contraceptive use increase upper-extremity deep vein thrombotic risk. Thromb Haemost 2003; 89:452.

3. Loret de Mola JR, Kiwi R, Austin C, Goldfarb JM. Subclavian deep vein thrombosis associated with the use of recombinant follicle-stimulating hormone (Gonal-F) complicating mild ovarian hyperstimulation syndrome. Fertil Steril 2000; 73:1253.

4. Rao AK, Chitkara U, Milki AA. Subclavian vein thrombosis following IVF and ovarian hyperstimulation: a case report. Hum Reprod 2005; 20:3307.

CPC determination after hypothermia

Q: 52 years old male coded in ER after he presented for chest pain. While the patient was prepared for cardiac catheterization, hypothermia was instituted. ER resident wrote an order for continuous infusion of midazolam. Ηурοthеrmiа ________________ the metabolism and excretion of midаzоlam. -  Select one

A) decreases

B) increases

Answer: A

Ηурοthеrmiа causes a decrease in the metabolism and excretion of midаzоlam. In patients who are bound to stay in therapeutic hypothermia protocol for 72 hours after cardiac arrest, it may take days for the drug to be cleared. It will hinder clinicians' ability to assess mental function after cardiac arrest for days or maybe even weeks. It is of vital importance to establish post-cardiac arrest brain injury (PCABI), also called hypoxic-ischemic brain injury (HIBI), after such an event.

One of the major outcomes that needs to be established is the cerebral performance category (CPC), particularly after extracorporeal cardiopulmonary resuscitation (ECPR). CPC score of 1 or 2 is preferred for survival. 

CPC is also called Glasgow–Pittsburgh cerebral performance category (CPC) scale:

CPC 1 or 2: Good neurological outcome

CPC 3 or 4: Neurological impairment

CPC 5: Brain death

#hemodynamic

#resuscitation

#ECMO

References:

1. Rey A, Rossetti AO, Miroz JP, et al. Late Awakening in Survivors of Postanoxic Coma: Early Neurophysiologic Predictors and Association With ICU and Long-Term Neurologic Recovery. Crit Care Med 2019; 47:85.

2. Hostler D, Zhou J, Tortorici MA, et al. Mild hypothermia alters midazolam pharmacokinetics in normal healthy volunteers. Drug Metab Dispos 2010; 38:781.

3. Abrams D, MacLaren G, Lorusso R, Price S, Yannopoulos D, Vercaemst L, Bělohlávek J, Taccone FS, Aissaoui N, Shekar K, Garan AR, Uriel N, Tonna JE, Jung JS, Takeda K, Chen YS, Slutsky AS, Combes A, Brodie D. Extracorporeal cardiopulmonary resuscitation in adults: evidence and implications. Intensive Care Med. 2022 Jan;48(1):1-15. doi: 10.1007/s00134-021-06514-y. Epub 2021 Sep 10. PMID: 34505911; PMCID: PMC8429884.

R value

Q: What is the significance of R value in liver hepatology?

Answer: The R-value, also called the R factor, may help to differentiate the type of liver injury, i.e., hepatocellular versus cholestatic. The formula is 

R value  =  (ALТ  ÷  ULN AԼT)  /  (alkaline phosphatase  ÷  ULN alkaline phosphatase)

ULN: Upper limit of normal

The R-value is interpreted as follows:

• ≥5: Hepatocellular injury
• >2 to <5: Mixed pattern
• ≤2: Cholestatic injury

          

#hepatology

          

          

References:

          

 1. Kalas MA, Chavez L, Leon M, Taweesedt PT, Surani S. Abnormal liver enzymes: A review for clinicians. World J Hepatol. 2021 Nov 27;13(11):1688-1698. doi: 10.4254/wjh.v13.i11.1688. PMID: 34904038; PMCID: PMC8637680.

 2. Fontana RJ, Liou I, Reuben A, Suzuki A, Fiel MI, Lee W, Navarro V. AASLD practice guidance on drug, herbal, and dietary supplement-induced liver injury. Hepatology. 2023 Mar 1;77(3):1036-1065. doi: 10.1002/hep.32689. Epub 2023 Feb 17. PMID: 35899384; PMCID: PMC9936988.

CVP via Jugular veins

Q: Which of the following veins can be used to estimate jugular venous pressure (JVP) - select one

A) internal jugular (IJ) 

B) external jugular (EJ)

C) both

Answer: C

Traditionally, the IJ vein is used at the bedside to assess the volume status or Right Atrial Pressure clinically. It is larger in diameter, less tortuous, and has no valves.

However, despite its limitations, EJ should also be evaluated simultaneously as the pulsation of the external jugular vein is more easily seen, and inspection of this venous pulse alone has been shown to correlate with direct measurements made by a central venous catheter positioned in the right atrium.

#hemodynamic

Reference:

Vinayak AG, Levitt J, Gehlbach B, et al. Usefulness of the external jugular vein examination in detecting abnormal central venous pressure in critically ill patients. Arch Intern Med 2006; 166:2132.

Stigmata of liver cirrhosis

Q: What are Muehrcke's nails?

Answer: Muehrcke's nails, also called Muehrcke's lines or Muehrcke's striae, are white bands across the second, third, and fourth fingernails. In other words, they are the manifestations of leukonychia due to an abnormality in the vasculature of the nail bed. This is one of the stigmata of liver cirrhosis but can occur in other diseases such as nephrotic syndrome, glomerulonephritis, malnutrition, and in mountain climbers.

The objective of this question is to highlight the importance of (vanishing art of) physical exams in clinical medicine. 

The authors of this website use liver cirrhosis as an example here. Liver cirrhosis is a classic disease where history and physical exam can establish the diagnosis without any labs or imaging, though it should be done to re-confirm the diagnosis. Some of the classic stigmata of cirrhosis are: 

• jaundice
• spider angiomas (or nevi or telangiectasias)
• palmar erythema
• pruritus
• xerosis
• xanthelasma
• paper money skin
• muehrcke's nails
• hepatomegaly 
• ascites
• caput medusa
• splenomegaly
• dupuytren's contracture
• gynecomastia
• scant chest hair and axillary hair 
• asterixis
• fetor hepaticus

#physical-exam

#hepatology

#nephrology

References:

1. MUEHRCKE RC. The finger-nails in chronic hypoalbuminaemia; a new physical sign. Br Med J. 1956 Jun 9;1(4979):1327-8. doi: 10.1136/bmj.1.4979.1327. PMID: 13316143; PMCID: PMC1980060.

2. Schwartz RA, Vickerman CE. Muehrcke's lines of the fingernails. Arch Intern Med. 1979 Feb;139(2):242. PMID: 434982.

3. Smith A, Baumgartner K, Bositis C. Cirrhosis: Diagnosis and Management. Am Fam Physician. 2019 Dec 15;100(12):759-770. PMID: 31845776.

GBS in HIV

Q: Guillain-Barré syndrome(GBS) tends to occur in ΗІV infection during which phase? - select one

A) early

B) late

Answer: A

Although GBS can occur in any stage of НΙV infection, but it tends to occur in very early phase. It is thought to be due to acute HІV seroconversion and following immune reconstitution syndrome from the highly active antiretroviral therapy.

#neurology

#ID

Reference:

Piliero PJ, Fish DG, Preston S, et al. Guillain-Barré syndrome associated with immune reconstitution. Clin Infect Dis 2003; 36:e111.

Rasmussen's aneurysm

Q: What is Rasmussen's aneurysm?

Answer: Rasmussen's aneurysm is a pulmonary artery aneurysm adjacent to or within a tuberculous cavity. It may rupture and lead to fatal hemoptysis. Rasmussen's aneurysm is caused by weakening of the pulmonary artery wall from adjacent cavitary tuberculosis.

#pulmonary

#ID

References:

1. Chatterjee K, Colaco B, Colaco C, Hellman M, Meena N. Rasmussen's aneurysm: A forgotten scourge. Respir Med Case Rep. 2015 Aug 12;16:74-6. doi: 10.1016/j.rmcr.2015.08.003. PMID: 26744661; PMCID: PMC4681976.

2. Marak JR, Kumar T, Gara H, Dwivedi S. Rasmussen aneurysm: Case series of a rare complication of Pulmonary Tuberculosis. Respir Med Case Rep. 2023 Jul 20;45:101897. doi: 10.1016/j.rmcr.2023.101897. PMID: 37577119; PMCID: PMC10413191.

3. Fadul KY, Alsayed A, Abdalla E, Mohamed RS, Salman AM, Meer A, Fadul A. Rasmussen's Aneurysm in Active Pulmonary Tuberculosis: A Case Report. Cureus. 2024 Aug 29;16(8):e68148. doi: 10.7759/cureus.68148. PMID: 39347312; PMCID: PMC11438579.

Cryo-poor plasma

Q: 43 year old female is transferred to ICU with diagnosis of thrombocytopenic purpura (TTP). Looking at previous records, you found a similar episode 4 years ago. It is mentioned that patient didn't respond to regular plasma exchange and required cryo-poor plasma exchange. What is cryo-poor plasma? 

 Answer: Cryo-poor plasma or cryosupernatant refers to plasma from which cryoprecipitate has been removed. The resulting plasma has reduced Factor VIII, von Willebrand factor, Factor XIII, fibronectin, and fibrinogen levels. Cryo-poor plasma may treat relapsing TTP, for which regular plasma exchange is ineffective. 

The rationale for using cryo-poor plasma in these refractory patients is that no additional von Willebrand factor will be administered to these patients who already have too much von Willebrand factor activity due to the presence of extra-large multimers of vWf. Caution: It is not a component regularly stocked in the blood bank. Usually, it will require special preparation and advance notice.

 

#hematology 

 Reference: 

Marcela P. Mafra, Maria Meritxell Roca Mora, Amanda Godoi, Andres Valenzuela - Cryoprecipitate-Poor Plasma Instead of Fresh Frozen Plasma As Replacement Therapy in Thrombotic Thrombocytopenic Purpura: A Systematic Review and Meta-Analysis - Blood (2023) 142 (Supplement 1): 2629.- https://doi.org/10.1182/blood-2023-188500

Anaphylaxis after rectal exam

Case: 54 years old male is admitted to ICU with pneumonia. Patient is found to be moderately anemic. To be complete in evaluation and to rule out possible GI bleed, you asked resident to do rectal exam for guaiac stool. Resident performed rectal exam with latex-free gloves and surgilube (surgical lubricant). 10 minutes later patient coded with severe anaphylactic reaction. What could be a reason assuming no new medication administered?

Answer: Possible allergic reaction to Chlorhexidine

Surgilubes (surgical lubricants, aka KY Jelly) are usually considered innocuous compounds, but they contain chlorhexidine. Patients with severe allergies to chlorhexidine may react badly, particularly if it enters blood circulation after a rectal exam.

#allergy-immunology

#physical exam

References:

1. A Case of Anaphylaxis to Chlorhexidine during Digital Rectal Examination - J Korean Med Sci. 2008 June; 23(3): 526–528.

2. Anaphylaxis to the chlorhexidine component of Instillagel®: a case series - Advance Access published online on November 5, 2008, - British Journal of Anaesthesia

3. Chlorhexidine anaphylaxis in Auckland - Br. J. Anaesth., May 1, 2009; 102(5): 722 - 723.

4. Chlorhexidine anaphylaxis: case report and review of the literature - Contact Dermatitis. 2004 Mar;50(3):113-6

Hypotensive symptoms (ACE-I vs ARB)

Q: 58 years old noncompliant male is admitted to ICU with hypertensive crisis. He has improved after intravenous infusion of anti-hypertensive. Now ICU team is considering to switch over his IV anti-hypertensive to oral. Because of his previous history of congestive heart failure (CHF) and diabetes, ACE-Inhibitor (ACE-I) or angiotensin II receptor blockers (ARBs) are under consideration. Another factor to consider is autonomic dysfunction because of his diabetes. Which group of drugs are more prone to cause hypotensive symptoms? - select one

A) ACE-Is

B) ARBs

Answer: B

ARBs have an advantage over ACE-Is when it comes to cough and angioedema. But, hypotensive symptoms are more common with ARBs.

In patients who may have underlying autonomic dysfunction (like our patient in this question), it can be severe. It may require permanent discontinuation. This effect persists for a while after discontinuation (see reference #2). A desirable 'washout period' should be taken into consideration before exposing a patient to any such other risk (see reference #3)

#hemodynamic

#pharmacology

References:

1. ONTARGET Investigators, Yusuf S, Teo KK, et al. Telmisartan, ramipril, or both in patients at high risk for vascular events. N Engl J Med 2008; 358:1547.

2. Lee JH, Kim YY, Heo HJ, Kim G, Oh C. Severe refractory hypotension during induction of general anesthesia in patient after 48 hours of azilsartan discontinuation: A case report. Medicine (Baltimore). 2023 Nov 24;102(47):e36126. doi: 10.1097/MD.0000000000036126. PMID: 38013296; PMCID: PMC10681524.

3. Hojo T, Shibuya M, Kimura Y, Otsuka Y, Fujisawa T. Refractory Hypotension During General Anesthesia Despite Withholding Telmisartan. Anesth Prog. 2020 Jun 1;67(2):86-89. doi: 10.2344/anpr-67-02-02. PMID: 32633774; PMCID: PMC7342806.

H2blockers and heart

Q; 42 years old male is admitted to ICU with Small Bowel Obstruction. Patient is made NPO. Also, famotidine is prescribed as an intravenous bid dose. During the administration of IV famotidine, the patient became hypotensive, and cardiac arrhythmia was noted on the monitor, which degenerated into cardiac arrest. H2-blockers (H2B) tend to cause? - select one

A) Sinus bradycardia

B) Sinus tachycardia

Answer: A

The use of anti-ulcer medications is common in the ICU. Although not common, rapid infusion of H2B may cause sinus bradycardia, hypotension, atrioventricular (AV) blocks, prolongation of the QT interval, and cardiac arrest. If possible, it is preferred to use the oral route as its bioavailability is not much affected by food, though first-pass metabolism may cause some decreased effects. Unfortunately, our patient in question can not have it. In such cases, slow administration is preferred. 

Risk factors for cardiac arrest are rapid intravenous infusion, high dose, renal or hepatic dysfunction(delays clearance), and underlying heart condition.

#pharmacology

#cardiology

References:

1. Hinrichsen H, Halabi A, Kirch W. Clinical aspects of cardiovascular effects of H2-receptor antagonists. Eur J Clin Invest 1995; 25 Suppl 1:47.

2. Lee KW, Kayser SR, Hongo RH, et al. Famotidine and long QT syndrome. Am J Cardiol 2004; 93:1325.

Vitamins, Pregnancy and Asthma

Q: 24 years old female is admitted to ICU with severe exacerbation of Asthma. While recovering, her spouse, who also has history of severe asthma, inquires about a news report that some vitamin intake by mother during pregnancy may reduce the risk of developing Asthma in the offspring. Which vitamin has been shown to reduce such risk in the early childhood of offspring? - select one

A) Vitain A

B) Vitamin B

C) Vitamin C

D) Vitamin D

E) Multi-Vitamin

Answer: D

There is a weak evidence of high-dose vitamin D intake (2000 to 4000 IU/day) by women during pregnancy - that reduces the risk of developing early life wheezing and allergic rhinitis, at least up to the age of 3-5 years in their children. This effect has been said to be more pronounced in northern climates (away from the equator). The effect is at least a 20% reduction. This effect is independent of other related factors such as maternal smoking status, maternal intake of vitamin E, zinc, and calcium, and vitamin D intake by the children. 

The proposed mechanism involves immunomodulation of multiple cell types, notably dendritic and T regulatory cells, and effects on in-utero lung development.

The high dose intake is in addition to the recommended dietary allowance (RDA) of 600 IU/day of vitamin D (the standard dose of prenatal vitamins). 

#ob-gyn

#vitamins

References:

1. Litonjua AA, Carey VJ, Laranjo N, et al. Effect of Prenatal Supplementation With Vitamin D on Asthma or Recurrent Wheezing in Offspring by Age 3 Years: The VDAART Randomized Clinical Trial. JAMA 2016; 315:362.

2. Erkkola M, Kaila M, Nwaru BI, et al. Maternal vitamin D intake during pregnancy is inversely associated with asthma and allergic rhinitis in 5-year-old children. Clin Exp Allergy 2009; 39:875.

3. Rothers J, Wright AL, Stern DA, et al. Cord blood 25-hydroxyvitamin D levels are associated with aeroallergen sensitization in children from Tucson, Arizona. J Allergy Clin Immunol 2011; 128:1093.

4. Litonjua AA. The role of vitamin D in the development, exacerbation, and severity of asthma and allergic diseases. In: Vitamin D and the lung: Mechanisms and disease associations, Litonjua AA (Ed), Humana Press, New York 2012.

5. Ramirez LG, Lee-Sarwar K, Kelly RS, et al. Association of Prenatal Maternal and Infant Vitamin D Supplementation with Offspring Asthma. Ann Am Thorac Soc 2024; 21:279.

BCIS

Q 28 years old motorbike rider, is taken to the Operating Room (OR) after motor vehicle trauma. The patient sustained multiple long bone fractures. Perioperatively, patient developed acute hypotension, severe hypoxia, cardiac arrhythmia and eventually went into cardiac arrest. Diagnosis of bone cement implantation syndrome (BCIS) is made. What is Bone cement implantation syndrome?

Answer:

BCIS is potentially a fatal complication during orthopedic surgeries, mostly associated with polymethylmethacrylate cement. The use of a long-stem femoral component is a significant risk factor. It is characterized by acute hypotension, hypoxia, neurologic symptoms, and cardiac arrhythmias. 

It is probably due to multiple mechanisms, including fat and marrow debris embolization, cement monomer toxicity, anaphylatoxin release, and prostaglandin release. 

Patients require aggressive volume resuscitation, oxygen, and usual care as in any shock situation.

#trauma

#orthopedics

#surgical critical care

References:

1. Saleh KJ, Kassim R, Yoon P, Vorlicky LN. Complications of total hip arthroplasty. Am J Orthop (Belle Mead NJ) 2002; 31:485.

2. Patterson BM, Healey JH, Cornell CN, Sharrock NE. Cardiac arrest during hip arthroplasty with a cemented long-stem component. A report of seven cases. J Bone Joint Surg Am 1991; 73:271.

3. Donaldson AJ, Thomson HE, Harper NJ, Kenny NW. Bone cement implantation syndrome. Br J Anaesth 2009; 102:12.

4. Mudgalkar N, Ramesh KV. Bone cement implantation syndrome: A rare catastrophe. Anesth Essays Res. 2011 Jul-Dec;5(2):240-2. doi: 10.4103/0259-1162.94796. PMID: 25885400; PMCID: PMC4173385.

AIP

Q: Which organ transplantation can be considered in extreme cases pf Acute Intermittent porphyria (AIP)? - select one

A) Pancreas

B) Liver

Answer: B

Interestingly, hepatic transplant is considered very effective in most cases of AIP where other therapies failed and were exhausted. It should be considered if patient does not have advanced motor neuropathy like quadriplegic patients.

Indications for liver transplant are frequent hospitalizations, unresponsiveness to hemin or givosiran, and poor quality of life. It should be highly considered in patients of AIP who develop primary liver cancer or have other acute hepatic porphyrias. 

It should be noted that traditionally used model for end-stage liver disease [MELD] score for liver transplantation does not apply to patients with AIP because they usually do not have advanced parenchymal liver damage even when neuropathic manifestations are severe. Patients with AIP and severe neuropathic symptoms who are being considered for liver transplant receive exception points for expedited waitlist priority. In the case of a living-related donor, the donor should be ruled out for AIP or latent AIP. Sibling donors may have asymptomatic AIP.

#hepatology

#transplantation

References:

1. Soonawalla ZF, Orug T, Badminton MN, et al. Liver transplantation as a cure for acute intermittent porphyria. Lancet 2004; 363:705.

2. Seth AK, Badminton MN, Mirza D, et al. Liver transplantation for porphyria: who, when, and how? Liver Transpl 2007; 13:1219.

3. Lissing M, Nowak G, Adam R, et al. Liver Transplantation for Acute Intermittent Porphyria. Liver Transpl 2021; 27:491.

EtCO2 and Epi

Q: During cardiac resuscitation, administration of epinephrine may cause erroneous ___________ in End-Tidal CO2 (EtCO2)? - select one

A) rise 

B) fall

Answer: B

The use of EtCO2 is on the rise in the ICU for various reasons. It is important to know the confounding factors.

EtCO2 may decrease rapidly moments after administration of epinephrine, although hemodynamics may show improvement. This effect is short-lived, though.

#resuscitation

#hemodynamics

Reference:

Sandroni C, De Santis P, D'Arrigo S. Capnography during cardiac arrest. Resuscitation 2018; 132:73.

TXA in UGIB

Q: Intravenous (IV) Tranexamic acid can be used as an effective adjuvant therapy in severe upper GI bleeding if it does not resolve appropriately with continuous Proton Pump Inhibitor (PPI) infusion.

A) true

B) False

Answer: B

Although Tranexamic acid is an effective antifibrinolytic agent, it failed to show any efficacy in patients with upper GI bleeds. It should not be used and has no major benefit.

Although there is weak evidence that it may decrease the risk of re-bleeding and the need for surgery, it has no significant effect on the number of blood transfusions or on mortality.

#GI

References:

1. Bennett C, Klingenberg SL, Langholz E, Gluud LL. Tranexamic acid for upper gastrointestinal bleeding. Cochrane Database Syst Rev 2014; :CD006640.

2. HALT-IT Trial Collaborators. Effects of a high-dose 24-h infusion of tranexamic acid on death and thromboembolic events in patients with acute gastrointestinal bleeding (HALT-IT): an international randomised, double-blind, placebo-controlled trial. Lancet 2020; 395:1927.

3. Burke E, Harkins P, Ahmed I. Is There a Role for Tranexamic Acid in Upper GI Bleeding? A Systematic Review and Meta-Analysis. Surg Res Pract. 2021 Jan 29;2021:8876991. doi: 10.1155/2021/8876991. PMID: 33564713; PMCID: PMC7864761.

FUO types

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Q: Which of the following is not a type of Fever of Unknown Origin (FUO)?

A) Classic FUO

B) Healthcare-associated FUO

C) Immunocompromised patients' FUO

D) Fictitious FUO

E) Travel-associated FUO

Answer: D

Multiple definitions of FUO have been proposed, but at its core, FUO is the fever in the absence of an identifiable cause despite reasonable evaluation for at least 3 weeks, above temperature >38.3°C. This definition describes classic FUO (choice A).

Healthcare-associated FUO

• ICU patient - Temperature >38.3°C (100.9°F) recorded several times in an ICU patient despite ≥3 days of investigations. The fever must not have been present or incubated upon admission.
• Non-ICU patient - Same definition as for ICU patients, except the patient is hospitalized but not critically ill.
• Post-operative patient—The same definition as for ICU patients applies, except fever is usually defined as ≥38.0°C (100.4°F).

FUO in immunocompromised patients

• Neutropenic patients - Temperature ≥38.3°C (100.9°F) or ≥38.0°C (100.4°F) sustained over one hour, recorded on several occasions over at least 3 days, despite appropriate antimicrobial therapy. Neutropenia is <500 neutrophils/microL or impending fall to that level within 48 hours.
• Patients with HIV and CD4 count <200 cells/microL - Despite appropriate evaluation, temperatures≥38.3°C (100.9°F) were recorded on several occasions for >3 weeks for outpatients or >3 days for inpatients.

Travel-associated FUO

A temperature>38.3°C (100.9°F) was recorded on several occasions for >3 weeks, despite 3 outpatient clinic evaluations, 1 week of intensive outpatient investigation, or 3 days of hospital-based evaluation, in a patient who traveled to another country, typically within the prior 12 months.

Although patients can have a fictitious fever, it is not a part of officially described types (at least yet) - Choice D

#ID

References:

1. Wright WF, Mulders-Manders CM, Auwaerter PG, et al. Fever of unknown origin (FUO) – A call for new research standards and updated clinical management. Am J Med 2022; 135:173.

Adapted from:

2. Wright W, Mackowiak P. Fever of unknown origin. In: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 8th ed, Bennett J, Dolin R, Blaser M (Eds), Elsevier Saunders 2015. p. 721.

3. Haidar G, Singh N. Fever of Unknown Origin. N Engl J Med. 2022; 386:463.

4. Wright WF, Auwaerter PG. Fever and fever of unknown origin: Review, recent advances, and lingering dogma. Open Forum Infect Dis 2020; 7:ofaa132.

5. Durack DT, Street AC. Fever of unknown origin – reexamined and redefined. Curr Clin Top Infect Dis 1991; 11:35.

bupropion and brain

Q: 22 years old female is admitted to ICU with severe electrolyte imbalance due to underlying bulimia nervosa. After repletion, patient's electrolyte profile improved. Patient's bulimia nervosa seems related to her desire to lose weight. She read on internet that Bupropion helps in depression as well as it leads to weight loss. It may be a good idea to prescribe Bupropion.

A) True

B) False

Answer: B

Patients with bulimia nervosa or anorexia nervosa seem to have an extremely high risk of developing seizures from bupropion. In fact this drug is contraindicated in such patients.

Bupropion increases risk of seizures, especially with immediate-release formulations. This risk is dose-dependent and increases with higher dosage.

Although Bupropion does indeed help in weight reduction, it would not be prudent to use this drug solely for the purpose of weight reduction.

#pharmacology

#neurology

References:

1. Fava M, Rush AJ, Thase ME, et al. 15 years of clinical experience with bupropion HCl: from bupropion to bupropion SR to bupropion XL. Prim Care Companion J Clin Psychiatry 2005; 7:106.

2. Johnston JA, Lineberry CG, Ascher JA, Davidson J, Khayrallah MA, Feighner JP, Stark P. A 102-center prospective study of seizure in association with bupropion. J Clin Psychiatry. 1991 Nov;52(11):450-6. PMID: 1744061.

3. Serretti A, Mandelli L. Antidepressants and body weight: a comprehensive review and meta-analysis. J Clin Psychiatry 2010; 71:1259.

open vs lap choly

Q: Laparoscopic cholecystectomy is preferred over open cholecystectomy due to lower rate of overall serious complication rates?

A) True

B) False

Answer: B

Laparoscopic cholecystectomy, popularly known as "lap chole," is considered the "gold standard" for gallstones requiring surgical intervention due to various advantages, such as less postoperative pain, aesthetically appealing, shorter length of stay, and less disability off days from work. However, the overall serious complication rate in laparoscopic cholecystectomy is higher than in open cholecystectomy. 

It should be accepted that this inference on higher complications is biased for two reasons. First, open cholecystectomy is now reserved only for complicated and challenging cases, and less open cholecystectomies are performed nowadays. Second, if lap-choly requires conversion to open-choly in OR, it results in severe complications, with worst injuries to bile duct, hepatic artery, or portal vein - and all this goes under the banner of lap-chole!!

#surgical-critical-care

#hepatology

#procedures

References:

1. Khan MH, Howard TJ, Fogel EL, et al. Frequency of biliary complications after laparoscopic cholecystectomy detected by ERCP: experience at a large tertiary referral center. Gastrointest Endosc 2007; 65:247.

2. Hogan NM, Dorcaratto D, Hogan AM, et al. Iatrogenic common bile duct injuries: Increasing complexity in the laparoscopic era: A prospective cohort study. Int J Surg 2016; 33 Pt A:151.

3. Visser BC, Parks RW, Garden OJ. Open cholecystectomy in the laparoendoscopic era. Am J Surg 2008; 195:108.