Daughter cysts

Case: 34 years old male who recently traveled to Middle East is admitted to ICU with abdominal pain and sepsis like picture. Workup led to the diagnosis of Echinococcosis. Ultrasound report reads "presence of daughter cysts." Why this information is important? 

Answer: Ultrasound plays an integral role in the diagnosis of Echinococcus with a sensitivity of up to 95 percent. The reason for this importance is due to its ability to classify as active, transitional, or inactive cysts based on the biologic activity.

The two well-known classifications are the World Health Organization (WHO) and the Gharbi classification.

Documentation of daughter cysts seems vital for management plan. Daughter cysts imply cysts that have involuted from the wall and reside within the larger cyst. It is to be noted that daughter cysts almost always form in the liver, and rarely in the lungs, in case they get involved.

Rupture of cysts in peritoneum may cause anaphylaxis and can be fatal.

#hepatology

#ID

#imaging

References:

1. World Health Organization Informal Working Group on Echinococcosis (WHO-IWGE) standardized classification of Echinococcal cysts. PAIR: Puncture, Aspiration, Injection, Re-Aspiration: An option for the treatment of Cystic Echinococcosis. WHO/CDS/CSR/APH/2001.6. World Health Organization 2001. 

2. Gharbi HA, Hassine W, Brauner MW, Dupuch K. Ultrasound examination of the hydatic liver. Radiology 1981; 139:459.

Renovascular hypertension in Afro-Americans and White patients

Q: Renovascular hypertension is more common in? (select one)

A) Afro-Americans patients

B) Caucasian patients

Answer: B

Any white male who developed severe hypertension (HTN) after age 55 should be evaluated for rnovascular etiology. Fortunately, it is correctable. Risk factors include previous history of HTN, hypertensive retinopathy, coronary artery disease, and peripheral arterial and aortic disease.

For poorly understood reason, renovascular disease is more common in white patients. It should be noted that this disparity may have some component of referral bias.

Interestingly, the complications of renovascular disease, if develop in a black patient is considerably more severe such as refractory hypertension, stroke or myocardial infarction.

#cardiovascular

#epidemiology

References:

1. Lewin A, Blaufox MD, Castle H, et al. Apparent prevalence of curable hypertension in the Hypertension Detection and Follow-up Program. Arch Intern Med 1985; 145:424.

2. Davis BA, Crook JE, Vestal RE, Oates JA. Prevalence of renovascular hypertension in patients with grade III or IV hypertensive retinopathy. N Engl J Med 1979; 301:1273.

3. Novick AC, Zaki S, Goldfarb D, Hodge EE. Epidemiologic and clinical comparison of renal artery stenosis in black patients and white patients. J Vasc Surg 1994; 20:1.

Sundowning and delirium

Q: Sundowning is a form of Delirium?

A) True

B) False

Answer: B

It is very hard to distinguish between sundowning and delirium. Unfortunately, despite known for decades, sundowning remained a poorly understood phenomenon manifested by behavioral deterioration in the evening hours. It usually occurs in elderly, demented, and institutionalized patients. The most plausible explanation is the impaired circadian regulation, superimposed on institutional environment like shift changes.

Patients with sundowning usually have an established pattern and no obvious medical illness. Any new pattern in a previously unknown sundowning should be presumed as delirium.

#psychiatry

#neurology

References:

1. Khachiyants N, Trinkle D, Son SJ, Kim KY. Sundown syndrome in persons with dementia: an update. Psychiatry Investig. 2011 Dec;8(4):275-87. doi: 10.4306/pi.2011.8.4.275. Epub 2011 Nov 4. PMID: 22216036; PMCID: PMC3246134.

2. Canevelli M, Valletta M, Trebbastoni A, Sarli G, D'Antonio F, Tariciotti L, de Lena C, Bruno G. Sundowning in Dementia: Clinical Relevance, Pathophysiological Determinants, and Therapeutic Approaches. Front Med (Lausanne). 2016 Dec 27;3:73. doi: 10.3389/fmed.2016.00073. PMID: 28083535; PMCID: PMC5187352.

Sphincter symptoms in MS

Q: If sphincter symptoms occur in patients with multiple sclerosis (MS), which is more common? (select one) 

 A) rectal

B) urinary 

Answer: B 

The spectrum of clinical symptoms is wide in MS patients, including sensory disturbance, motor weakness, visual disturbance, imbalance, fatigue, or cognitive difficulty. Patients may present with unilateral optic neuritis, painless diplopia, ataxia with gaze-evoked nystagmus, vertigo, unilateral facial numbness, or paroxysmal episodes of dysarthria or vertigo. 

In patients with partial transverse myelitis, Brown-Sequard syndrome occurs, causing sphincter symptoms, erectile dysfunction (males), and urinary urge incontinence. 

Rectal sphincter symptoms, though occur, are relatively less common.

 #neurology 

 References: 

 

1. Fingerman JS, Finkelstein LH. The overactive bladder in multiple sclerosis. J Am Osteopath Assoc. 2000 Mar;100(3 Suppl):S9-12. PMID: 10763312. 

 2. McCombe PA, Gordon TP, Jackson MW. Bladder dysfunction in multiple sclerosis. Expert Rev Neurother. 2009 Mar;9(3):331-40. doi: 10.1586/14737175.9.3.331. PMID: 19271942. 

 3. Nicholas R, Young C, Friede T. Bladder symptoms in multiple sclerosis: a review of pathophysiology and management. Expert Opin Drug Saf. 2010 Nov;9(6):905-15. doi: 10.1517/14740338.2010.501793. PMID: 20569078.

MRSA - Anbx choice

Q: 62 years old male with previous history of sick sinus syndrome and subcutaneous implanted permanent pacemaker (PPM) has been recovering in ICU from knee replacement surgery. Patient was admitted to ICU after more than-expected blood loss during surgery. The patient is now stable and designated as "Ready to Move" to ward by bedside nurse. On admission to ICU two days back, the admitting intern noted mild skin redness over the PPM site and sent culture from the skin area, which is now reported as Methicillin resistance Staphylococcus aureus (MRSA). Patient has no other clinical signs of infection. In fact, cardiology advised transferring patient to rehab directly from the ICU as there is no other inpatient need. Your choice of antibiotic? (select one)

A) Oral trimethoprim-sulfamethoxazole 

B) Oral doxycycline

C) Oral minocycline

D) Oral clindamycin

E) Intravenous (IV) Vancomycin

Answer: E

Although it is true that in mild MRSA skin and soft tissue infections (localized involvement with no systemic symptoms), an oral antibiotic may suffice. But, there are few instances when IV antibiotics should be used, as an extension of infections may become life-threatening. 

When soft tissues are in close proximity to any life or limb-saving indwelling device such as PPM, defibrillator, prosthetic joint, or a vascular graft, soft tissue infection should be considered a manifestation of device infection if it originates on the skin directly overlying the device. 

IV antibiotic for skin and soft tissues MRSA should always be considered when there is:

• extensive soft tissue involvement
• signs of systemic toxicity
• rapid progression of clinical manifestations
• persistence or progression of symptoms after 48 to 72 hours of oral therapy
• immunocompromise status
• proximity of soft tissue infection to an indwelling device

#ID

References:

1. Ruhe JJ, Smith N, Bradsher RW, Menon A. Community-onset methicillin-resistant Staphylococcus aureus skin and soft-tissue infections: impact of antimicrobial therapy on outcome. Clin Infect Dis 2007; 44:777.

2. Drugs for MRSA skin and soft-tissue infections. Med Lett Drugs Ther 2014; 56:39.

3. Daum RS. Clinical practice. Skin and soft-tissue infections caused by methicillin-resistant Staphylococcus aureus. N Engl J Med 2007; 357:380.

3 stages of yellow fever

Q: Which of the following is NOT among the three stages of Yellow fever infection? (select one)

A) infection 

B) transmission

C) remission

D) intoxication 

Answer: B

Yellow fever is unique in the sense that it has a period of about 48 hours of remission between acute illness and severe yellow fever known as the period of intoxication. About 15 percent of patients enter the multi-stage organ failure stage (intoxication).

Infection period lasts for 3-4 days with viremia and consists of high fever, relative bradycardia, malaise, headache, photophobia, lumbosacral pain, pain in the lower extremities, myalgia, anorexia, nausea, vomiting, restlessness, irritability, dizziness, flushed skin, reddening of the conjunctivae and gums, and epigastric tenderness. Hepatomegaly with transaminitis may be present, which is a risk for an intoxication period. Another characteristic physical sign is that the tongue is characteristically red at the tip and sides with a white coating in the center. Instead of leucocytosis, leukopenia with relative neutropenia is common.

Period of intoxication is marked by the return of fever, prostration, nausea, vomiting, epigastric pain, jaundice, oliguria, and hemorrhagic diathesis. At this stage, viremia starts to disappear and antibodies appear in the blood. Eventually, Muti-system organ failure (MSOF) ensues.

#infectious-disease

References:

1. Centers for Disease Control and Prevention (CDC). Fatal yellow fever in a traveler returning from Venezuela, 1999. MMWR Morb Mortal Wkly Rep 2000; 49:303.

2. Barnett ED. Yellow fever: epidemiology and prevention. Clin Infect Dis 2007; 44:850.

3. Tuboi SH, Costa ZG, da Costa Vasconcelos PF, Hatch D. Clinical and epidemiological characteristics of yellow fever in Brazil: analysis of reported cases 1998-2002. Trans R Soc Trop Med Hyg 2007; 101:169.

4. Kallas EG, D'Elia Zanella LGFAB, Moreira CHV, et al. Predictors of mortality in patients with yellow fever: an observational cohort study. Lancet Infect Dis 2019; 19:750.

Acute acalculous cholecystitis in the critically ill

Q: 52 year old diabetic male with now resolving sepsis (off pressors) found to develop severe right upper quadrant (RUQ) tenderness around 7 PM. STAT ultrasound showed distended acalculous gallbladder with thickened walls (4 mm). Diagnosis of acalculous Cholecystitis made. Time is now 10 PM. Your next step should be: (select one)

A) Make patient NPO. Follow-up with LFT (Conservative approach)

B) Make patient NPO. Start Antibiotics and call surgery in the morning

C) Make patient NPO. Start Antibiotics and call STAT Surgical consult

D) Call interventional radiology to perform percutaneous cholecystostomy

E) Call GI service to perform endoscopic gallbladder stent placement

Answer: C

When the diagnosis of acalculous cholecystitis is established, immediate intervention is indicated because of the high risk of rapid deterioration and gallbladder perforation. The definitive treatment of acalculous cholecystitis is cholecystectomy (open or laparoscopic). Surgical consultation takes precedence over any intervention.

In patients who are not surgical candidates, percutaneous cholecystostomy may be performed in interventional radiology as an alternative. Catheters are usually removed after approximately 3 weeks in critically ill patients who have undergone percutaneous cholecystostomy. This allows for the development of a mature track from the skin to the gallbladder.

Also, endoscopic gallbladder stent placement has been reported as an effective palliative treatment. This involves the placement of a double pigtail stent between the gallbladder and the duodenum during endoscopic retrograde cholangiopancreatography (ERCP).

#hepatology

References:

1. Gallaher JR, Charles A. Acute Cholecystitis: A Review. JAMA. 2022 Mar 8;327(10):965-975. doi: 10.1001/jama.2022.2350. PMID: 35258527.

2. Treinen C, Lomelin D, Krause C, Goede M, Oleynikov D. Acute acalculous cholecystitis in the critically ill: risk factors and surgical strategies. Langenbecks Arch Surg. 2015 May;400(4):421-7. doi: 10.1007/s00423-014-1267-6. Epub 2014 Dec 25. PMID: 25539703.

Picture Diagnosis - PAC

Q: 54 years old male is admitted to ICU with congestive heart failure. Pulmonary Artery Catheter (PAC) (swan-Ganz catheter) is floated? CXR 6 hours apart are shown below. Your diagnosis?

 

Answer: Pulmonary infarct 

A Swan-Ganz catheter has been inserted too far into the right pulmonary artery (A). Several hours later, an infiltrate is present in this region (B) as a result of lung infarction.

#procedures

#pulmonary

Reference:

Reinke RT, Higgins CB. Pulmonary infarction complicating the use of Swan-Ganz catheters. Br J Radiol. 1975 Nov;48(575):885-8. doi: 10.1259/0007-1285-48-575-885. PMID: 1218298.

Risk factors - postpartum depression

Q: 32 years old female, four weeks postpartum, is admitted to ICU with severe depression and suicidal ideation. Which of the following is more of a risk factor for postpartum depression? (select one)

A) Primiparity

B) Multiparity

Answer: B

Risk factors for postpartum major depression is divided into primary and secondary;

Primary:

• Depression during pregnancy
• A prior history of depression, either perinatal or non-perinatal

Secondary: 

• Stressful life events
• Poor social and financial support in the puerperium
• Perinatal anxiety symptoms and disorders
• Young age 
• Single marital status
• Multiparity
• Family history of postpartum depression or psychiatric illness
• Intimate partner violence 
• lifetime history of physical and/or sexual abuse
• Unintended/unwanted pregnancy [14,15,41,58]
• Negative attitudes toward pregnancy
• Fear of childbirth
• Poor perinatal physical health 
• Body image dissatisfaction
• Personality traits, such as neuroticism 
• History of premenstrual syndrome 
• Perinatal sleep disturbance 
• Season of delivery (mostly winter - less daylight)
• Adverse pregnancy and neonatal outcomes
• Breastfeeding issues 
• Childcare stress such as difficult infant temperament

#ob-gyn

#psychiatry

References:

1. O'Hara MW, McCabe JE. Postpartum depression: current status and future directions. Annu Rev Clin Psychol 2013; 9:379.

2. Agrawal I, Mehendale AM, Malhotra R. Risk Factors of Postpartum Depression. Cureus. 2022 Oct 31;14(10):e30898. doi: 10.7759/cureus.30898. PMID: 36465774; PMCID: PMC9711915.

3. Dubey A, Chatterjee K, Chauhan VS, Sharma R, Dangi A, Adhvaryu A. Risk factors of postpartum depression. Ind Psychiatry J. 2021 Oct;30(Suppl 1):S127-S131. doi: 10.4103/0972-6748.328803. Epub 2021 Oct 22. PMID: 34908678; PMCID: PMC8611548.

ODS and K

Q: Which of the following is the bigger risk factor in the development of osmotic demyelination syndrome (ODS), due to rapid reversal of chronic hyponatremia? (select one)

A) Concurrent hyperkalemia

B) Concurrent hypokalemia

Answer: B

Osmotic demyelination syndrome (ODS) is the most dreaded outcome if sodium is too aggressively and quickly treated in chronic hyponatremia. A few of the risk factors for the development of ODS are:

• sodium ≤105 mEq/L
• Concurrent hypokalemia
• History of alcohol abuse
• Acute or chronic hepatic disease
• Malnourishment
• Hypophosphatemia

#neurology

#electrolyte

References:

1. Ambati R, Kho LK, Prentice D, Thompson A. Osmotic demyelination syndrome: novel risk factors and proposed pathophysiology. Intern Med J. 2023 Jul;53(7):1154-1162. doi: 10.1111/imj.15855. Epub 2022 Sep 16. PMID: 35717664.

2. Reijnders TDY, Janssen WMT, Niamut SML, Kramer AB. Role of Risk Factors in Developing Osmotic Demyelination Syndrome During Correction of Hyponatremia: A Case Study. Cureus. 2020 Jan 2;12(1):e6547. doi: 10.7759/cureus.6547. PMID: 32042522; PMCID: PMC6996461.

Pseudomonas aeruginosa biofilm and Gentamicin

Q: 82 years old male is admitted to ICU from Nursing Home with severe urosepsis. The indwelling urinary catheter on arrival tends to show blue-green biofilm. Gentamicin is the drug of choice?

A) True

B) False

Answer: B

Escherichia coli, Enterococcus spp., and Pseudomonas aeruginosa are leading causes of institution-acquired Urinary Tract Infections (UTIs) when prolonged indwelling catheters are kept.

Pseudomonas aeruginosa causing catheter-associated UTIs produce biofilms. The majority of the isolates are multidrug-resistant. Gentamicin resistance correlated with increased biofilm production. Other risk factors for P. aeruginosa urosepsis are

• male sex
• longer hospitalization
• prior use of antibiotics

Outbreaks of P. aeruginosa urosepsis have been reported from contaminated urologic equipment or facilities due to Urodynamic equipment, a cystoscopy room via an unsealed drain, and a urology unit with a contaminated sink, scope, and bedside table.

#ID

References:

1. Suman E, Varghese S, Jose J. Gentamicin resistance in biofilm producing Pseudomonas aeruginosa causing catheter associated urinary tract infections. Indian J Med Sci 2005; 59:214.

2. Bilavsky E, Pfeffer I, Tarabeia J, et al. Outbreak of multidrug-resistant Pseudomonas aeruginosa infection following urodynamic studies traced to contaminated transducer. J Hosp Infect 2013; 83:344.

3. Boutiba-Ben Boubaker I, Boukadida J, Triki O, et al. [Outbreak of nosocomial urinary tract infections due to a multidrug resistant Pseudomonas aeruginosa]. Pathol Biol (Paris) 2003; 51:147.

DAH and UA

Q: 34 years old male is admitted to ICU with Diffuse Alveolar hemorrhage (DAH). Urinalysis (UA) should be sent.

A) True

B) False

Answer: A

It is important to rule out any associated pulmonary-renal syndromes particularly focal segmental necrotizing glomerulonephritis in any patient with DAH. This can be ruled out early in differential Diagnosis by normal UA. Abnormal UA may present as RBCs, WBCs, proteinuria, and/or red and white blood cell casts. Also, the serum chemistry profile is likely to show elevated plasma creatinine concentration.

#vasculitis

#pulmonary

#nephrology

#Differential-Diagnosis

References:

1. Boyle N, O'Callaghan M, Ataya A, Gupta N, Keane MP, Murphy DJ, McCarthy C. Pulmonary renal syndrome: a clinical review. Breathe (Sheff). 2022 Dec;18(4):220208. doi: 10.1183/20734735.0208-2022. Epub 2023 Jan 10. PMID: 36865943; PMCID: PMC9973488.

2. Saladi L, Shaikh D, Saad M, Cancio-Rodriguez E, D'Agati VD, Medvedovsky B, Uday KA, Adrish M. Pulmonary renal syndrome: A case report of diffuse alveolar hemorrhage in association with ANCA negative pauci-immune glomerulonephritis. Medicine (Baltimore). 2018 Jun;97(23):e10954. doi: 10.1097/MD.0000000000010954. PMID: 29879042; PMCID: PMC5999515.

3. Talwar D, Vadala R, Talwar S, Pahuja S, Prajapat D. Pulmonary-Renal Syndrome: A Real-World Experience From a Tertiary Care Pulmonary Center in North India. Cureus. 2022 Jan 17;14(1):e21327. doi: 10.7759/cureus.21327. PMID: 35186586; PMCID: PMC8849225.

Diplopia in MS

Q: Diplopia in Multiple Sclerosis (MS) is usually? (select one)

A) painful

B) painless

Answer: B

If a patient with MS encounters diplopia, it is usually painless. This occurs due to internuclear ophthalmoplegia or sixth nerve palsy. In contrast, optic neuritis is usually unilateral, painful, and with monocular visual loss manifested by visual blurring or scotoma.

Partial transverse myelitis may occur, usually with predominant sensory symptoms, including a partial Brown-Sequard syndrome. Sphincter symptoms usually occur is such situations.

Interestingly many of these symptoms resolved without treatment though now with more awareness, most patient receives treatment for MS exacerbation or relapse.

#neurology

References:

1. Costello F. Vision Disturbances in Multiple Sclerosis. Semin Neurol. 2016 Apr;36(2):185-95. doi: 10.1055/s-0036-1579692. Epub 2016 Apr 26. PMID: 27116725.

2. Graves J, Balcer LJ. Eye disorders in patients with multiple sclerosis: natural history and management. Clin Ophthalmol. 2010 Dec 6;4:1409-22. doi: 10.2147/OPTH.S6383. PMID: 21188152; PMCID: PMC3000766.

DOACs and bioavailability

Q: Which of the following requires gastric acidity for absorption? (select one)

A) Dabigatran (Pradaxa)

B) Apixaban (Eliquis)

C) Edoxaban (Savaysa, Lixiana)

D) Rivaroxaban (Xarelto)

Answer: A

Direct oral anticoagulants (DOACs) are now increasingly used instead of Warfarin in most cardiac diseases particularly Atrial Fibrillation (A.fib.). It is imperative to understand the bioavailability, interactions with other drugs, and pharmacokinetics to find a balance between therapeutic dose and risk of bleeding. 

Not all DOACs are created equal when it comes to bioavailability. Their response varies depending on the food, kidney function, age, and other variables. Out of all DOACs, Dabigatran and Rivaroxaban need special mention.

Dabigatran is unique out of all DOACs in that though its absorption remains unaffected by food, but capsule needs to be taken intact and requires gastric acidity for absorption. It is mostly cleared by kidney.

Rivaroxaban is interesting in the sense that it behaves differently at lower and higher doses. At 10 mg dose, it has 80-100% bioavailability and stays unaffected by food. But, at 20 mg dose, bioavailability is 66% if taken when fasting, and increased if taken with food!

#pharmacology

#cardiology

References:

1. Gronich N, Stein N, Muszkat M. Association between use of pharmacokinetic-interacting drugs and effectiveness and safety of direct acting oral anticoagulants: Nested case-control study. Clin Pharmacol Ther 2021; 110:1526.

2. Lexicomp Online. Copyright © 1978-2023 Lexicomp, Inc. All Rights Reserved.

3. Drugs@FDA: FDA-Approved Drugs. U.S. Food and Drug Administration. Available https://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm (Accessed on September 9, 2023).

Leukocytosis steroid vs infection induced leukocytosis

Q: Leukocytosis is a known side effect of steroid treatment. What would be the best way to differentiate it from infection induced leukocytosis?

Answer: A left shift in total WBC count with more than 6 percent band forms is a good indicator of infection. Also, request can be made to lab to look for the appearance of toxic granulation which are rare in corticosteroid-induced leukocytosis.

#lab-medicine

Reference: 

Shoenfeld Y, Gurewich Y, Gallant LA, Pinkhas - Prednisone-induced leukocytosis. Influence of dosage, method and duration of administration on the degree of leukocytosis.- J.Am J Med. 1981 Nov;71(5):773-8.

Blood tests in clozapine-induced myocarditis

Q: 32 years old male patient with history of severe schizophrenia, who was discharged from the hospital a month ago, now presented at Emergency Department with complaints of shortness of breath and has acute congestive heart failure. Clozapine-induced myocarditis was diagnosed. Combination of which two tests can give 100 percent sensitivity in detecting clozapine-induced myocarditis? (select one)

A) C-reactive protein (CRP) & troponin 

B) Eosinophilia & B-Type Natriuretic Peptide (BNP)

C) BNP & Troponin

D) Potassium and Creatinine

Answer: A

Besides classic symptoms of congestive heart failure (CHF), i.e., shortness of breath or leg edema - a combination of elevations of two blood tests: CRP and Troponins, provide almost 100 percent sensitivity in detecting clozapine-induced myocarditis (choice A). 

Eosinophilia is also common but is less reliable and often a delayed finding (choice B).

BNP is universally common in CHF and does not provide diagnostic accuracy for a specific cause (Choices B and C).

In the late stage, Hyperkalemia and renal insufficiency may ensue with decreased cardiac pump function and cardio-renal syndrome. This is also universal in all late CHF patients (choice D).

#cardiology

#laboratory-medicine

Reference:

Ronaldson KJ, Fitzgerald PB, Taylor AJ, et al. A new monitoring protocol for clozapine-induced myocarditis based on an analysis of 75 cases and 94 controls. Aust N Z J Psychiatry 2011; 45:458.

Polyphonic vs. monophonic wheeze

Q: 62 years old male is admitted to ICU with respiratory distress. Patient has been diagnosed with asthma in the Emergency department (ED) due to wheezing. Patient has a long history of tobacco smoking and the CT chest showed a bronchial mass. How the wheezing sound of asthma can be differentiated from the wheezing sound of a local bronchial narrowing due to bronchogenic cancer?

Answer: Polyphonic vs. monophonic pitch

The diagnosis of asthma is typically made by the associated history of previous episodes, family history, other clinical signs, and workup. It usually occurs early in the life. Wheezes in asthma are audible most commonly on expiration. They can be heard as sounds of multiple different pitches, called "polyphonic." They start and stop at various points in the respiratory cycle and vary in tone and duration over time. In contrast, the wheezing due to a local bronchial narrowing such as in an aspirated foreign body or bronchogenic tumor, is usually single i.e., monophonic, and begins and ends at the same point in each respiratory cycle.

#pulmonary

#physical exam

References:

1. De La Torre Cruz J, Cañadas Quesada FJ, Ruiz Reyes N, García Galán S, Carabias Orti JJ, Peréz Chica G. Monophonic and Polyphonic Wheezing Classification Based on Constrained Low-Rank Non-Negative Matrix Factorization. Sensors (Basel). 2021 Feb 28;21(5):1661. doi: 10.3390/s21051661. PMID: 33670892; PMCID: PMC7957792.

2. Andrès E, Gass R, Charloux A, Brandt C, Hentzler A. Respiratory sound analysis in the era of evidence-based medicine and the world of medicine 2.0. J Med Life. 2018 Apr-Jun;11(2):89-106. PMID: 30140315; PMCID: PMC6101681.

High FiO2 and atelactasis

Q: One of the tricks to avoid atelectasis is to employ high FiO2?

A) True

B) False

Answer: B

The high fraction of inspired oxygen (FiO2) in the air actually expedites atelectasis.

Normal (ambient) air contains 79% of inert nitrogen. As human lungs are exposed to ambient air since birth, it is in equilibrium with the nitrogen that's dissolved in pulmonary arteriolar and capillary blood. In normal circumstances, at the distal end of the bronchial tree, the pressure gradient forcing nitrogen into mixed venous blood is extremely low, and so nitrogen absorbs slowly. In other words, it acts like an alveolar splint or scaffolding and thus prevents or delays atelectasis. In contrast, intraalveolar oxygen quickly reabsorbed along a steep pressure gradient into deoxygenated mixed venous blood.

High FiO2 in the air disperses nitrogen. As described above, distal atelectasis develops quickly.

#pulmonary

#ventilators

References:

1. Park M, Jung K, Sim WS, Kim DK, Chung IS, Choi JW, Lee EJ, Lee NY, Kim JA. Perioperative high inspired oxygen fraction induces atelectasis in patients undergoing abdominal surgery: A randomized controlled trial. J Clin Anesth. 2021 Sep;72:110285. doi: 10.1016/j.jclinane.2021.110285. Epub 2021 Apr 7. PMID: 33838534.

2. Benoît Z, Wicky S, Fischer JF, Frascarolo P, Chapuis C, Spahn DR, Magnusson L. The effect of increased FIO(2) before tracheal extubation on postoperative atelectasis. Anesth Analg. 2002 Dec;95(6):1777-81, table of contents. doi: 10.1097/00000539-200212000-00058. PMID: 12456458.

HRS and clonidine

Q: Which of the Clonidine is helpful in hepatorenal syndrome? (select one)

A) Oral

B) Intravenous

Answer: B

The pathology of hepatorenal syndrome is extremely complex involving many mechanisms mainly consisting of:

• Arterial vasodilatation in the splanchnic circulation triggered by nitric oxide activity.
• Progressive rise in cardiac output and fall in systemic vascular resistance (SVR)
• Hypotension-induced activation of the renin-angiotensin and sympathetic nervous systems
• Bacterial translocation from the intestine into the mesenteric lymph nodes
• Decline in kidney perfusion associated with a decrease in glomerular filtration rate (GFR) and sodium excretion

Intravenous (IV) clonidine, which is a sympatholytic agent increases the renal blood flow and subsequently raises the GFR by about 25 percent. Interestingly this effect is not demonstrated with oral ingestion.

Given the above pathogenesis of hepatorenal syndrome, ornipressin or other vasopressin analogs help by elevating mean arterial pressure, reducing plasma renin activity and norepinephrine concentration, increase in renal blood flow, and GFR and sodium excretion.

#hepatology

#nephrology

References:

1. Esler M, Dudley F, Jennings G, et al. Increased sympathetic nervous activity and the effects of its inhibition with clonidine in alcoholic cirrhosis. Ann Intern Med 1992; 116:446.

2.  Mindikoglu AL, Pappas SC. New Developments in Hepatorenal Syndrome. Clin Gastroenterol Hepatol 2018; 16:162.

3. Runyon BA, Squier S, Borzio M. Translocation of gut bacteria in rats with cirrhosis to mesenteric lymph nodes partially explains the pathogenesis of spontaneous bacterial peritonitis. J Hepatol 1994; 21:792.

4. Lenz K, Hörtnagl H, Druml W, et al. Ornipressin in the treatment of functional renal failure in decompensated liver cirrhosis. Effects on renal hemodynamics and atrial natriuretic factor. Gastroenterology 1991; 101:1060.

COWS

Q: All of the following are included in the Clinical Opioid Withdrawal Scale (COWS) EXCEPT?

A) Resting pulse rate

B) GI upset

C) Sweating

D) Yawning

E) Craving for abused substance

Answer: E

Clinical Opioid Withdrawal Scale (COWS) is mostly based on physical signs of withdrawal. History plays an imminent role, but the craving for abused substances is not included in COWS. Scale counts the following signs:

• Resting pulse rate
• GI upset'
• Sweating
• Tremor
• Restlessness
• Yawning
• Pupil size
• Anxiety or irritability
• Bone or joint aches
• Gooseflesh skin
• Runny nose or tearing

Score: 

- 5 to 12 = mild

- 13 to 24 = moderate

- 25 to 36 = moderately severe

- more than 36 = severe withdrawal

Scale is available free via any search engine or online medical calculators.

Reference:

Wesson DR, Ling W. The Clinical Opiate Withdrawal Scale (COWS). J Psychoactive Drugs 2003; 35:253.

Paperbag in Hyperventilation Syndrome

Q: 34 years old male is admitted to the ICU with severe anxiety and hyperventilation. Arterial blood gas (ABG) showed severe respiratory alkalosis with PH 7.7. The immediate maneuver should be to encourage him to breathe into a paper bag.

A) True

B) False

Answer: B

Despite popular belief, very little data supports breathing into a paper bag for hyperventilation syndrome. On the contrary, it can be harmful by inducing hypoxemia, which may quickly turn fatal in patients with underlying respiratory and/or cardiac disease. 

Also, in the past, attempts have been made to try this maneuver to counter metabolic acidosis if it occurs concurrently with respiratory alkalosis (mixed acid-base disorder), but it has been found to actually worsen the acidosis by dampening respiratory compensation.

#acid-base

#psychiatry

Reference:

Callaham M. Hypoxic hazards of traditional paper bag rebreathing in hyperventilating patients. Ann Emerg Med 1989; 18:622.

CXR in hepatic abscess

Q: All of the following can be diagnostic clues in Chest-X-ray (CXR) in patients with hepatic abscess EXCEPT? (select one)

A) Right basilar atelectasis 

B) Right hemidiaphragm elevation

C) Right pleural effusion

D) Right loculated Pneumothorax (PTX)

E) Pneumobilia

Answer: D

In this era of CT scans, ultrasounds, and MRIs, CXR is usually ignored in hepatic pathologies but when combined with a clinical picture, they can provide valuable indirect signs including basilar atelectasis, hemidiaphragm elevation, and pleural effusion on the right side. Moreover, gas within the abscess or biliary tree (pneumobilia) or beneath the diaphragm can be seen.

Loculated Pneumothorax (PTX) is unlikely (choice D).

#hepatology

#radiology

#pulmonary

References:

1. Kozielewicz DM, Sikorska K, Stalke P. Liver abscesses – from diagnosis to treatment. Clin Exp Hepatol. 2021 Dec;7(4):329–36. doi: 10.5114/ceh.2021.110998. Epub 2021 Nov 26. PMCID: PMC8977881.

2. Crompton JG, Jimenez JM, Chen F, Hines OJ. Man with liver abscess and pneumobilia. Surgery. 2018 Apr;163(4):965-966. doi: 10.1016/j.surg.2017.09.013. Epub 2018 Jan 3. PMID: 29306540.

PICCs and CLABSIs

Q: Peripherally Inserted Central Catheters (PICCs) are a viable option to decrease Central Line-Associated Bloodstream Infections (CLABSIs).

A) True

B) False

Answer: B

Unfortunately, in recent years PICCs have been promoted as a viable option to replace Internal Jugular (IJ), Subclavian (SC), and femoral central lines on the pretext of decreasing infections and risk of thrombosis. Although it is true that PICCs may decrease injury to the vessels and pneumothorax, they actually carry a higher risk of thrombosis(odds ratio 2.55). This risk is even higher in ICU and in patients with malignancy. They are also not recommended to be used as a strategy to reduce bloodstream CLABSIs.

Also, PICCs (as well as SC-central lines) should be ideally avoided in patients with GFR less than 45 mL/minute.

#procedures

#ID

References:

1. Chopra V, Anand S, Krein SL, et al. Bloodstream infection, venous thrombosis, and peripherally inserted central catheters: reappraising the evidence. Am J Med 2012; 125:733.

2. Yokoe DS, Anderson DJ, Berenholtz SM, et al. A compendium of strategies to prevent healthcare-associated infections in acute care hospitals: 2014 updates. Infect Control Hosp Epidemiol 2014; 35 Suppl 2:S21.

3. Bhutani G, El Ters M, Kremers WK, et al. Evaluating safety of tunneled small bore central venous catheters in chronic kidney disease population: A quality improvement initiative. Hemodial Int 2017; 21:284.

DE Novo R-CHF

Q: Patients with de novo right-sided congestive Heart Failure (CHF) may often have more severe symptoms than those with Left-sided CHF.

A) True

B) False

Answer: A

Unfortunately, R-CHF is usually underdiagnosed and less appreciated, although the symptoms may be more severe than L-CHF. It may go untreated for a longer period. To make things complicated, many of these patients may have an antecedent history of known L-CHF.

De novo R-CHF should be suspected in patients with valve pathologies, pulmonary hypertension, or congenital heart disease. One of the reasons these patients stay undiagnosed as symptoms appear to be more of abdominal or pulmonary diseases due to underlying ascites or dyspnea. Symptoms can be non-specific, such as easy fatigability, orthopnea, paroxysmal nocturnal dyspnea, chest discomfort, abdominal distention, anorexia, early satiety, and decreased exercise capacity. These symptoms are due to elevation in intracardiac pressures that reduce coronary perfusion pressure, hepatosplanchnic congestion, and gut edema.

Clinically, they may have jugular venous distention. The examiner should look for a prominent V wave. Kussmaul sign may be noticeable in advanced disease. Lower extremity edema is common. Another interesting feature is cachexia. Patients may have lesser muscle mass but stable or even increased body weight. This is due to fluid retention. Abdominal distention, positive fluid wave, and hepatomegaly should be looked for. Right Ventricular heave may be present with a loud P2 sound (caused by pulmonary hypertension). A murmur of tricuspid regurgitation (generally a holosystolic murmur over the left lower sternal border) may be present. 

#cardiology

#clinical-exam

References:

1. Konstam MA, Kiernan MS, Bernstein D, et al. Evaluation and Management of Right-Sided Heart Failure: A Scientific Statement From the American Heart Association. Circulation 2018; 137:e578.

2. Gorter TM, van Veldhuisen DJ, Bauersachs J, et al. Right heart dysfunction and failure in heart failure with preserved ejection fraction: mechanisms and management. Position statement on behalf of the Heart Failure Association of the European Society of Cardiology. Eur J Heart Fail 2018; 20:16.

AI to estimate survival in cancer patients

Q: 68 years old male is transferred to ICU with septic shock. Patient has advanced metastatic lung cancer. The family decides on palliative care. EnMed student rotating in the ICU inquired about using machine learning technology to determine survival estimates in advanced cancer. Machine learning technology shown to provide better prognostication when compared to conventional logistic regression regarding survival estimate in advanced terminal cancer? 

A) True

B) False

Answer: A

Unfortunately, most of the existing integrated prognostication tools do not accurately identify most patients who will die beyond 6 months. Newer data is showing that machine learning technology may allow better prognostication by modeling both linear and nonlinear interactions among many variables i.e., age, sex, comorbidity, stage of metastasis, solid vs. nonsolid tumor, labs, EKGs, and other variables. Artificial Intelligence (AI) based algorithms can differentiate between patients into high and low prognostic groups. Some of these algorithms are internally validated (single-center) in the studies. 

Although not yet accepted as a standard of care in practice, their role in the near future would be highly enhanced regarding prognosis in advanced oncology patients.

#oncology

#AI

References:

1. Elfiky AA, Pany MJ, Parikh RB, Obermeyer Z. Development and Application of a Machine Learning Approach to Assess Short-term Mortality Risk Among Patients With Cancer Starting Chemotherapy. JAMA Netw Open 2018; 1:e180926.

2. Bertsimas D, Dunn J, Pawlowski C, et al. Applied Informatics Decision Support Tool for Mortality Predictions in Patients With Cancer. JCO Clin Cancer Inform 2018; 2:1.

3. Parikh RB, Manz C, Chivers C, et al. Machine Learning Approaches to Predict 6-Month Mortality Among Patients With Cancer. JAMA Netw Open 2019; 2:e1915997.

4. 

Manz CR, Chen J, Liu M, et al. Validation of a Machine Learning Algorithm to Predict 180-Day Mortality for Outpatients With Cancer. JAMA Oncol 2020; 6:1723.

ROX index

Q: What is ROX index?

Answer: (SpO2/FiO2)/RR

ROX Index predicts the Risk of intubation, particularly in patients who are not tachypneic but may require higher oxygen demand such as High Flow Nasal Cannula (HFNC).The ROX index is calculated as 

(peripheral arterial oxygen saturation/fraction of inspired oxygen [expressed as a percentage]/respiratory rate) 

A ROX index of >4.88 at 2, 6, and 12 hours post-initiation of HFNC indicated a less likely need for endotracheal intubation. 

The ROX index may be very useful in patients who gets admitted to ICU with impending respiratory failure. It's best utility lies where it is combined with overall clinical picture.

#pulmonary

#ventilators

References:

1. Li A, Cove ME, Phua J, et al. Expanding the utility of the ROX index among patients with acute hypoxemic respiratory failure. PLoS One 2022; 17:e0261234.

2. Junhai Z, Jing Y, Beibei C, Li L. The value of ROX index in predicting the outcome of high flow nasal cannula: a systematic review and meta-analysis. Respir Res 2022; 23:33.

3. Zhou X, Liu J, Pan J, et al. The ROX index as a predictor of high-flow nasal cannula outcome in pneumonia patients with acute hypoxemic respiratory failure: a systematic review and meta-analysis. BMC Pulm Med 2022; 22:121.

Gender ratio in fatal anaphylaxis

Q: Fatal anaphylaxis from contrast media is more common in? (select one)

A) Females

B) Males

Answer: B

For reasons not fully understood, males tend to have more fatal outcomes from contrast media. This is also true for insect stings.

When it comes to fatal food anaphylaxis, the sex ratio is approximately equal, but young boys are more prone to have fatal cow's milk reactions, and adolescent girls are affected more by peanut reactions.

#allergy

#immunology

References:

1. Pumphrey R. Anaphylaxis: can we tell who is at risk of a fatal reaction? Curr Opin Allergy Clin Immunol 2004; 4:285.

2. Bock SA, Muñoz-Furlong A, Sampson HA. Fatalities due to anaphylactic reactions to foods. J Allergy Clin Immunol 2001; 107:191.

3. Pumphrey RS. Fatal anaphylaxis in the UK, 1992-2001. Novartis Found Symp 2004; 257:116.

4. Pouessel G, Claverie C, Labreuche J, et al. Fatal anaphylaxis in France: Analysis of national anaphylaxis data, 1979-2011. J Allergy Clin Immunol 2017; 140:610.

IVF in sepsis

Q: In early management of sepsis, intravenous fluids (IVF) should be given at 30 mL/kg per? (select one)

A) actual body weight

B) ideal body weight

Answer: A

Beside other aspects of management in early sepsis like antibiotics and achieving control over ABC i.e., Airway, Breathing and Circulation - the most profound management is to achieve and/or preserve tissue perfusion. It is mostly achieved by the aggressive administration of intravenous fluids (IVF). The fluid recommended is either any balanced crystalloid or normal saline at 30 mL/kg. This should be given by actual body weight. 

Per guidelines, IVF should be started within one hour and completed within the first three hours following the presentation.

#hemodynamics

#sepsis

References:

1. Macdonald S. Fluid Resuscitation in Patients Presenting with Sepsis: Current Insights. Open Access Emerg Med. 2022 Nov 29;14:633-638. doi: 10.2147/OAEM.S363520. PMID: 36471825; PMCID: PMC9719278.

2. Zampieri FG, Bagshaw SM, Semler MW. Fluid Therapy for Critically Ill Adults With Sepsis: A Review. JAMA. 2023 Jun 13;329(22):1967-1980. doi: 10.1001/jama.2023.7560. PMID: 37314271.

3. Brown RM, Semler MW. Fluid Management in Sepsis. J Intensive Care Med. 2019 May;34(5):364-373. doi: 10.1177/0885066618784861. Epub 2018 Jul 9. PMID: 29986619; PMCID: PMC6532631.

temporal artery biopsy in GCA

Q: 62 years old Caucasian female of Scandinavian descent with past history of polymyalgia rheumatica is recovering in ICU from community-acquired pneumonia. She complained of loss of vision in one eye with ipsilateral jaw claudication. Giant Cell Arteritis (GCA) is diagnosed, and steroid treatment is promptly initiated. Temporal artery biopsy is required to be performed within 24-48 hours? 

A) True

B) False

Answer: B

Initial temporal artery biopsy in suspected cases of GCA can be performed within two to four weeks of treatment. The vital management is to commence glucocorticoid once the diagnosis is suspected. An initial biopsy can be ipsilateral. At least 1 cm of length is recommended for the sample. Biopsy of the contralateral side should be considered if the unilateral biopsy and other workup for temporal arteritis and large vessel vasculitis remain negative but the clinical suspicion stays high.

The biopsy can be delayed for preparation as the resolution of the inflammatory infiltrate occurs slow, and the histopathologic evidence stays for about 2-4 weeks despite steroid therapy. Said that the earlier the biopsy is done, the yield would be higher.

#vasculitis

#rheumatology

References:

1. Achkar AA, Lie JT, Hunder GG, et al. How does previous corticosteroid treatment affect the biopsy findings in giant cell (temporal) arteritis? Ann Intern Med 1994; 120:987.

2. Narváez J, Bernad B, Roig-Vilaseca D, et al. Influence of previous corticosteroid therapy on temporal artery biopsy yield in giant cell arteritis. Semin Arthritis Rheum 2007; 37:13.

3. Jakobsson K, Jacobsson L, Mohammad AJ, et al. The effect of clinical features and glucocorticoids on biopsy findings in giant cell arteritis. BMC Musculoskelet Disord 2016; 17:363.

4. Maleszewski JJ, Younge BR, Fritzlen JT, et al. Clinical and pathological evolution of giant cell arteritis: a prospective study of follow-up temporal artery biopsies in 40 treated patients. Mod Pathol 2017; 30:788.

LAI Haloperidol

Q; 24 years old male is getting discharged from ICU to floor after resolution of his acute schizophrenia. Previously patient has been on home Haloperidol. Psychiatry service changed his medicine to Long Acting Injectable (LAI) form of Haloperidol. Pharmacy service called ICU team to confirm as the dose sounds unusual. The prescribed LAI dose of Haloperidol  is usually? (select one)

A) equivalent to daily dose of Haloperidol

B) half the daily dose of Haloperidol

C) double the daily dose of Haloperidol

D) 10-20 times the daily dose of Haloperidol

Answer: D

The dose of haloperidol when prescribed as LAI is 10 to 20 times the previous daily dose of oral haloperidol. It is usually given as once a month. The maximum dose in this regard is 100 mg, regardless of previous dose of daily requirement. If dose needs to be exceeded, it should be handled by an expert of the field. Also, LAI form is usually prescribed when patient has been on daily haloperidol for about 8-12 weeks.

Again, specialized person i.e., psychiatry service should be consulted at each step of drug modification/overlap etc.

#psychiatry

References:

1. Ereshefsky L, Saklad SR, Jann MW, et al. Future of depot neuroleptic therapy: pharmacokinetic and pharmacodynamic approaches. J Clin Psychiatry 1984; 45:50.

2. Jann MW, Ereshefsky L, Saklad SR. Clinical pharmacokinetics of the depot antipsychotics. Clin Pharmacokinet 1985; 10:315.

3. Correll CU, Kim E, Sliwa JK, Hamm W, Gopal S, Mathews M, Venkatasubramanian R, Saklad SR. Pharmacokinetic Characteristics of Long-Acting Injectable Antipsychotics for Schizophrenia: An Overview. CNS Drugs. 2021 Jan;35(1):39-59. doi: 10.1007/s40263-020-00779-5. Epub 2021 Jan 28. PMID: 33507525; PMCID: PMC7873121.