ICP leveling

Q: 22 years old male is admitted to Neuro-ICU after head trauma. Intra-cranial catheter is inserted to monitor intra-cranial pressure (ICP). Where should ICP monitoring be leveled (zeroed)? (select one)

A) patient’s face

B) right atrium (heart)

Answer: A

In contrast to central venous pressure (CVP), the transducer for ICP is supposed to be leveled at the part of the patient’s face that corresponds to the Foramen of Monro. 

A few external points described are:

1. The outer canthus of the eye.

2. Halfway between the outer canthus of the eye and the tragus of the ear.

3. Patient’s external auditory meatus.

4. If the patient is lateral, between the eyebrow.

#procedures

References:

1. Reinstrup P, Unnerbäck M, Marklund N, Schalen W, Arrocha JC, Bloomfield EL, Sadegh V, Hesselgard K. Best zero level for external ICP transducer. Acta Neurochir (Wien). 2019 Apr;161(4):635-642. doi: 10.1007/s00701-019-03856-x. Epub 2019 Mar 8. PMID: 30848373; PMCID: PMC6431298.

2. Munakomi S, M Das J. Intracranial Pressure Monitoring. 2023 Feb 12. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan–. PMID: 31194438.

3. Changa AR, Czeisler BM, Lord AS. Management of Elevated Intracranial Pressure: a Review. Curr Neurol Neurosci Rep. 2019 Nov 26;19(12):99. doi: 10.1007/s11910-019-1010-3. PMID: 31773291.

Hepatojugular reflux

Q: Hepatojugular reflux should be performed with? (select one)

A) mouth open

B) mouth close

Answer: A

The hepatojugular reflux can be a useful test in patients with right-sided heart failure. This test should be performed while the patient is lying down with the upper body at a 45-degree angle from the horizontal plane. The patient keeps the mouth open and breathes normally to prevent Valsalva's maneuver, which can give a false-positive test. Moderate pressure is then applied over the middle of the abdomen for 30 to 60 seconds. Hepatojugular reflux occurs if the height of the neck veins increases by at least 3 cm and the increase is maintained throughout the compression period. Transient elevation in JVP may be normal.

#physical exam

#cardiology

Reference:

Vaidya Y, Bhatti H, Dhamoon AS. Hepatojugular Reflux. 2023 Jul 17. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan–. PMID: 30252353.

DTS

Q: Duke treadmill score (DTS) contains all of the following EXCEPT? (select one)

A) Exercise time 

B) ST deviation 

C) Angina score 

D) Increase in heart rate

Answer: D

Duke treadmill score (DTS) is a validated treadmill score created from the data of 2758 consecutive patients seen over 11 years (1969-1980). The median age of 49 of patients with chest pain. These patients underwent both exercise treadmill testing and coronary angiography. DTS provides added independent prognostic information.

The formula for DTS is:

DTS = Exercise time (minutes) - (5 x ST deviation) - (4 x angina score)

- Exercise time is based on minutes completed on Bruce protocol (or equivalent to Bruce protocol)

- ST deviation is the maximum deviation (in mm) compared with baseline

- Angina score: 0 for no pain, 1 for nonlimiting pain, 2 for exercise limiting pain

Patients are classified as:

• Low risk, if score ≥+5
• Moderate risk, if score from -10 to +4
• High risk, if score ≤-11

Reportedly, DTS works better in females.

#cardiology

References:

1. Shaw LJ, Peterson ED, Shaw LK, Kesler KL, DeLong ER, Harrell FE Jr, Muhlbaier LH, Mark DB. Use of a prognostic treadmill score in identifying diagnostic coronary disease subgroups. Circulation. 1998 Oct 20;98(16):1622-30. doi: 10.1161/01.cir.98.16.1622. PMID: 9778327.

2. Günaydın ZY, Bektaş O, Gürel YE, Karagöz A, Kaya A, Kırış T, Zeren G, Yazıcı S. The value of the Duke treadmill score in predicting the presence and severity of coronary artery disease. Kardiol Pol. 2016;74(2):127-34. doi: 10.5603/KP.a2015.0143. Epub 2015 Jul 23. PMID: 26202537.

Quantifying fluid responsiveness

Q: 48 years old male with previous history of HIV is admitted to ICU with septic shock. The ICU fellow decided to float pulmonary artery (swan-Ganz) catheter to better assess the fluid responsiveness. A predicted or good fluid responsiveness after 500 mL of intravenous fluid (IVF) is an increase in cardiac output (CO) by approximately? (select one)

A) 5 percent

B) 15 percent

C) hard to predict

Answer: C

It is a common practice in ICU to try to quantify fluid responsiveness by improvement in 'numbers' such as central venous pressure (CVP), cardiac output, Mean blood pressure (MAP), or pulmonary artery diastolic pressure (PADP). 

Although CO is expected to rise by 15 percent after a half liter of IVF, most of the parameters by numbers have very poor predictive values. Clinical exam and good clinical judgment continue to supersede any particular number including improvement in mental status, urine output, skin turgor, and mucous membrane dryness. The whole clinical picture should be read with all parameters. All quantifying numbers are highly influenced by cardiovascular, cardiac valvular, pulmonary, renal, and hepatic functions. Also, positive pressure ventilation, invasive or noninvasive may make numbers erroneous.

The objective of the question is to emphasize that clinical judgment should never be suppressed solely by the "numbers."

#hemodynamics

References:

1. Marik PE, Baram M, Vahid B. Does central venous pressure predict fluid responsiveness? A systematic review of the literature and the tale of seven mares. Chest 2008; 134:172.

2. Michard F, Teboul JL. Predicting fluid responsiveness in ICU patients: a critical analysis of the evidence. Chest 2002; 121:2000.

3. Osman D, Ridel C, Ray P, et al. Cardiac filling pressures are not appropriate to predict hemodynamic response to volume challenge. Crit Care Med 2007; 35:64.

smoldering Waldenstrom macroglobulinemia

Q: Smoldering Waldenström macroglobulinemia (WM) is considered to be the severe form of Waldenström macroglobulinemia?

A) True

B) False

Answer: B

Macroglobulinemia is the production of excess IgM monoclonal protein that occurs in certain clonal lymphoproliferative disorders and plasma cell dyscrasias. This is an umbrella term for various pathologies such as monoclonal gammopathy of undetermined significance of the IgM type (IgM MGUS), smoldering Waldenström macroglobulinemia, Waldenström macroglobulinemia (WM), and a number of related disorders in which an IgM monoclonal protein is detected, such as chronic lymphocytic leukemia (CLL), a number of lymphoma variants, and primary (AL) amyloidosis.

Patients who meet the criteria for WM but do not have any clinical symptoms and lack evidence of anemia, hepatosplenomegaly, lymphadenopathy, or hyperviscosity are considered to have smoldering WM. These patients do not require therapy but  monitoring. 

#hematology

References:

1. Fonseca R, Hayman S. Waldenström macroglobulinaemia. Br J Haematol 2007; 138:700.

2. Kyle RA, Benson JT, Larson DR, et al. Progression in smoldering Waldenstrom macroglobulinemia: long-term results. Blood 2012; 119:4462.

Auricular-cartilage calcification in longstanding adrenal insufficiency

Q: 36 years old patient is admitted to ICU with syncope, hypotension, and hypoglycemia. Patient is a known case of chronic adrenal insufficiency.  Medical student documented in his physical exam an absence of auricular-cartilage calcification. In patients with chronic adrenal insufficiency, auricular-cartilage calcification occurs exclusively in? (select one)

A) male

B) female

Answer: A

For reasons not fully understood, auricular-cartilage calcification in longstanding primary or secondary adrenal insufficiency occurs exclusively in men. This unusual sign was first reported almost seven decades ago.

Although the cause is known as chronic cortisol deficiency, this natural gender bias is hard to explain. Moreover, it does not reverse or improve with glucocorticoid replacement.

#endocrinology

References:

1. Barkan A, Glantz I. Calcification of auricular cartilages in patients with hypopituitarism. J Clin Endocrinol Metab 1982; 55:354.

2. Calvo Catalá J, Hortelano Martínez E, González-Cruz Cervellera MI, et al. [Calcification of auricular cartilages in a patient with adrenal insufficiency: presentation of a case and review of the literature]. An Med Interna 1994; 11:496.

3. JARVIS JL, JENKINS D, SOSMAN MC, THORN GW. Roentgenologic observations in Addison's disease; a review of 120 cases. Radiology 1954; 62:16.

Types of pseudoallergy

Q: 22 years old athletic basketball player with no past medical history is brought from college game after he developed a reaction to Non-steroidal Anti-inflammatory Drug (NSAID) during the game for ankle pain. Patient developed severe urticaria with angioedema. Patient has no known drug allergy (NKDA). Patient is successfully treated with epinephrine, nebs, H1-H2 combo, and steroids, and admitted to ICU for observation. Immunology service diagnosed him with pseudo-allergy. Patient probably had which type of Pseudoallergic reaction? (select one)

A) Type 1 

B) Type 2 

C) Type 3 

D) Type 4 

Answer: C

Although the classic four types of true allergic reactions are very well known, it is not much known that pseudoallergic reactions are also of four types. Some literature also accounts for Types 5 & 6. 

Whenever any reaction doesn't fit the classic IgE or IgG type reactions, they are called pseudoallergy. Aspirin and NSAIDs are most common to cause pseudoallergy. 

 

In contrast to true allergy types, pseudoallergy classification is based on clinical symptoms. NSAIDs are very well known to have such reactions:

Type 1 – asthma and rhinosinusitis

Type 2 – urticaria/angioedema

Type 3 – NSAID-induced urticaria/angioedema in an otherwise asymptomatic person

Type 4 – Blended (mixed respiratory and/or cutaneous) reactions in an otherwise asymptomatic person

#allergy

#pharmacology

References:

1. Stevenson DD, Sanchez-Borges M, Szczeklik A. Classification of allergic and pseudoallergic reactions to drugs that inhibit cyclooxygenase enzymes. Ann Allergy Asthma Immunol 2001; 87:177.

2. Waller DG. Allergy, pseudo-allergy and non-allergy. Br J Clin Pharmacol. 2011 May;71(5):637-8. doi: 10.1111/j.1365-2125.2011.03976.x. PMID: 21480945; PMCID: PMC3093068.

3. Zhang B, Li Q, Shi C, Zhang X. Drug-Induced Pseudoallergy: A Review of the Causes and Mechanisms. Pharmacology. 2018;101(1-2):104-110. doi: 10.1159/000479878. Epub 2017 Nov 15. PMID: 29136631.

Face wound in marine driller

Case: 25 year old patient presented to emergency room with complaint of 2-day history of symmetrical and descending muscular weakness along with diplopia. He denies any fever or chills. He does give history of having an injury to the face. He works as a marine driller. His symptoms are progressively getting worse. His vital signs reveal no fever but bradycardia with heart rate of 48 and blood pressure of 120/80 mm hg. His vital capacity is 1 liter (33% of predicted). He was admitted to intensive care unit. What could be the probable diagnosis? (select one)

A)     Myasthenia Gravis

B)     Lambert-Eaton syndrome

C)    Guillain-Barre’s syndrome

D)    Poliomyelitis 

E)    Botulism

Answer: Botulism 

Botulism has an acute onset with bilateral cranial neuropathies and symmetric descending weakness. Key features include:

• Patient is afebrile
• Symmetric neurological deficit
• Patient is responsive
• Normal or slow heart rate and normal blood pressure
• No sensory deficit
• Blurred vision

Treatment:

• Equine serum botulism antitoxin
• Penicillin G intravenously 3 grams every 4 hours

Differential diagnosis: 

• Mysthenia Gravis
• Lambert-Eaton syndrome
• Guillain-Barre’s syndrome
• poliolmyelitis 
• Ticks paralysis
• heavy metal intoxication

#ID

Reference: 

Jeffery IA, Karim S. Botulism. 2023 Jul 17. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan–. PMID: 29083673.

RRT in TLS

Q: Which of the following Renal Replacement Therapy (RRT) is preferred in Tumor Lysis Syndrome (TLS)? (select one)

A) Continuous venovenous hemodialysis (CVVHD) 

B) Intermittent hemodialysis (iHD) 

Answer: A

CVVHD is considered better in TLS as iHD may cause rebound hyperphosphatemia after the session is over. Moreover, the threshold of initiating RRT in TLS is low. Early RRT in TLS has been shown to be beneficial. This is particularly true when rasburicase is not available or has not been used. 

Early RRT in TLS saves lives as there is a tendency for potentially rapid potassium release and accumulation. Also, complete recovery of renal function is usual when early RRT is applied which rapidly lowers uric acid and phosphate concentrations. Acute uric acid nephropathy leads to oliguria and results in complete renal failure, which can be prevented by early RRT. The response to early RRT is very robust in decreasing uric acid. In contrast, hyperphosphatemia is relatively more resistant to RRT, though still it gives excellent results.

Besides other known indications of RRT in ICU, some of the major indications of RRT in TLS are:

1. persistent hyperkalemia

2. hyperphosphatemia-induced symptomatic hypocalcemia

3. calcium-phosphate product ≥70 mg2/dL2

Complete recovery of renal function is usual when early RRT is applied which rapidly lowers uric acid and phosphate concentrations. 

#nephrology

#electrolytes

#oncology

References:

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

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

3. Pichette V, Leblanc M, Bonnardeaux A, et al. High dialysate flow rate continuous arteriovenous hemodialysis: a new approach for the treatment of acute renal failure and tumor lysis syndrome. Am J Kidney Dis 1994; 23:591.

D&C risks

Q: 26 years old patient has been taken to Obstetrics-OR for Dilatation and Curettage (D&C) for termination of molar pregnancy. The ICU team has been called due to perforation of uterus during the procedure. Pregnant uterus tends to have a higher rate of perforation?

A) True

B) False

Answer: A

Uterine perforation is the common immediate complication of D&C. As expected, it is high when emergent D&C is required such as in postpartum hemorrhage particularly in case of a molar pregnancy because uterus is more friable in molar pregnancy. 

In contrast to diagnostic D&C, pregnant uterus tends to perforate more as the uterine wall is soft and bulkier. The risk of perforation rises higher in proportion to advancement of pregnancy. 

Management is either observation or surgical, depending on the level of perforation, risk of surgical procedure, and level of available institutional support/backup.

#Ob-gyn

#surgical-critical-care

References:

1. Ben-Baruch G, Menczer J, Shalev J, et al. Uterine perforation during curettage: perforation rates and postperforation management. Isr J Med Sci 1980; 16:821.

2. Hefler L, Lemach A, Seebacher V, et al. The intraoperative complication rate of nonobstetric dilation and curettage. Obstet Gynecol 2009; 113:1268.

3. Kaali SG, Szigetvari IA, Bartfai GS. The frequency and management of uterine perforations during first-trimester abortions. Am J Obstet Gynecol 1989; 161:406.

SLS

Q: Shrinking lung syndrome (SLS) is a phenomenon occurs in? (select one)

A) Interstitial lung disease (ILD)

B) Systemic Lupus Erythematosus (SLE)

Answer: B

Reflexly, it may occur to answer SLS as an integral part of ILD. However, it occurs in SLE with the provision that there is no evidence of underlying ILD on a CT scan. Some of the other features as expected are dyspnea, episodic pleuritic pain, and progressive decrease in: 

• lung volumes
• diffusing capacity for carbon monoxide (DLCO)
• forced vital capacity (FVC) but normal ratio of forced expiratory volume in one second [FEV1]/FVC) - restrictive pattern
• pulmonary function tests (PFTs).

If it occurs in SLE patients, the average time is about four years from the time of diagnosis.

No established cause has been found yet, but the presumed mechanism is myositis/myopathy causing elevation of the diaphragms. Another plausible hypothesis is that chronic pleural inflammation impairs the deep inspiration and leads to atelectasis, parenchymal reorganization, and decreased lung compliance.

Glucocorticoids, immunosuppressive therapy, Theophylline, and beta-adrenergic agonists may help.

#rheumatology

#pulmonary

References:

1. Karim MY, Miranda LC, Tench CM, et al. Presentation and prognosis of the shrinking lung syndrome in systemic lupus erythematosus. Semin Arthritis Rheum 2002; 31:289.

2. Warrington KJ, Moder KG, Brutinel WM. The shrinking lungs syndrome in systemic lupus erythematosus. Mayo Clin Proc 2000; 75:467.

3. Munoz ML, Gelber AC, Houston BA. Into thin air: shrinking lung syndrome. Am J Med 2014; 127:711.

V710

Q: 52 years old basic sciences professor is admitted a night prior to ICU for an elective coronary artery bypass grafting (CABG) in the morning. Being a scientific person, he preferred to use Staphylococcus aureus vaccine (V710) instead of perioperative antibiotics. He heard about this vaccine a few years ago in a conference and was impressed. V710 vaccine is an approach in perioperative antimicrobials, and though not covered by insurance, has shown to improve outcomes in CABG surgeries.

A) True

B) False

Answer: B

S. aureus vaccine, also known as V710 remained investigational since last decade, and is not approved for clinical practice. Moreover, the independent data monitoring committee at Duke University Medical Center recommended termination of the study after the second interim analysis because of safety concerns, low efficacy, and chances of increased mortality.

#cardiac-surgery

#ID

Reference:

Fowler VG, Allen KB, Moreira ED, Moustafa M, Isgro F, Boucher HW, Corey GR, Carmeli Y, Betts R, Hartzel JS, Chan IS, McNeely TB, Kartsonis NA, Guris D, Onorato MT, Smugar SS, DiNubile MJ, Sobanjo-ter Meulen A. Effect of an investigational vaccine for preventing Staphylococcus aureus infections after cardiothoracic surgery: a randomized trial. JAMA. 2013 Apr 3;309(13):1368-78. doi: 10.1001/jama.2013.3010. PMID: 23549582.

Initiation of dialysis and nephrologist's experience

Q: 56 years old male with Adult Polycystic Kidney Disease (APKD), and at the level of Chronic Kidney Disease 5 (CKD-5) is admitted to ICU with sepsis due to acute cholecystitis. Fortunately, patient is recovering without any compromise on his baseline kidney function and urine output. The nephrology fellow indicated starting hemodialysis, but the nephrology attending overrides the fellow's decision and decided to continue to watch. Less experienced nephrologists tend to start dialysis for chronic kidney insufficiency earlier than experienced nephrologists.

A) True

B) False

Answer: A

The objective of the question is to highlight the fact that the timing to start dialysis in chronic kidney patients is quite complicated. The attitude of the nephrologist, experience, nature of the practice, US vs non-US graduation, region of practice, institutional culture, and employment status play a significant role. 

For example, a massive retrospective study of about 83,000 patients published in 2014 showed that physician graduation from nondomestic medical schools may factor in this matter. Experienced nephrologists may wait longer. Also, another study that looked into data spanning over 9 years found that salaried nephrologists at Veterans Affairs (VA) facilities are less likely to initiate dialysis among patients with an eGFR ≥10 mL/min/1.73 m2 compared with non-VA nephrologists.

#nephrology

References:

1. Slinin Y, Guo H, Li S, et al. Provider and care characteristics associated with timing of dialysis initiation. Clin J Am Soc Nephrol 2014; 9:310.

2. Yu MK, O'Hare AM, Batten A, et al. Trends in Timing of Dialysis Initiation within Versus Outside the Department of Veterans Affairs. Clin J Am Soc Nephrol 2015; 10:1418.

Diastolic BP in VA ECMO

Q: In predicting survival in patients who receive V-A ECMO, higher diastolic blood pressure is a? (select one)

A) protective factor

B) risk factor

Answer: A

A survival prediction model for those receiving V-A ECMO, derived from the Extracorporeal Life Support Organization (ELSO) Registry, called the SAVE (Survival After VA ECMO) score published in 2015. It identified risk and potential protective factors:

Risk factor: 

• Postcardiotomy cardiogenic shock
• Chronic renal failure
• Longer duration of ventilation prior to ECMO initiation
• Pre-ECMO organ failures
• Pre-ECMO cardiac arrest
• Congenital heart disease
• Lower pulse pressure
• Lower serum bicarbonate

Potentially protective factors: 

• Younger age
• Lower body weight
• Acute myocarditis
• Heart transplant
• Refractory ventricular tachycardia (VT) or fibrillation (VF)
• Higher diastolic blood pressure
• Lower peak inspiratory pressure

#hemodynamics

#procedures

#cardiology

Reference:

Schmidt M, Burrell A, Roberts L, et al. Predicting survival after ECMO for refractory cardiogenic shock: the survival after veno-arterial-ECMO (SAVE)-score. Eur Heart J 2015; 36:2246.

EoE I-SEE

Q: 34 years old male is admitted to ICU with acute dysphagia due to food impaction in esophagus. GI service performed emergent endoscopy. Subsequent workup led to the diagnosis of eosinophilic esophagitis (EoE). The calculated Severity for Eosinophilic Esophagitis (I-SEE) score is reported as 15. Which of the following is NOT a part of I-SEE score? (select one)

A) Symptoms such as food impaction

B) Endoscopic features such as strictures

C) Eosinophilia in Complete Blood Count (CBC)

D) Histologic finding – Eosinophil burden

Answer: C

The following three clinical features are assigned a point value depending on findings

1. Symptoms and associated complications – Symptom frequency, food impaction, hospitalization

2. Endoscopic features – Edema, furrows, exudates, rings, strictures

3. Histology – Eosinophil burden per high power field

- 1 to 6 points = mild

- 7 to 14 points = moderate

- 15 points or higher = severe

I-SEE can be trend during subsequent visits.

Initially, eosinophilic esophagitis was abbreviated as "EE," but due to confusion with erosive esophagitis, now abbreviated as "EoE."

#GI

References:

1. Dellon ES, Khoury P, Muir AB, et al. A Clinical Severity Index for Eosinophilic Esophagitis: Development, Consensus, and Future Directions. Gastroenterology 2022; 163:59.

2. Cotton CC, Moist SE, McGee SJ, et al. A Newly Proposed Severity Index for Eosinophilic Esophagitis is Associated With Baseline Clinical Features and Successful Treatment Response. Clin Gastroenterol Hepatol 2023; 21:2534.

DVT - clinical exam

Q: 32 years old female is transferred to ICU with shortness of breath (SOB). On examination calf area in left lower extremity is noted to have swelling, edema, pain and warmth. Which of the following has the highest specificity for Deep Venous Thrombosis (DVT)? (select one)

A) swelling 

B) pain 

C) warmth 

Answer: C

DVT is the most probable diagnosis when a patient presents with unilateral (can be bilateral in some cases) lower extremity swelling, pain, warmth, and erythema, particularly when other clinical signs are present like SOB. 

The specificity for warmth, swelling and pain is 48, 33 and 19 percent respectively. In contrast sensitivity is 72, 97 and 86 percent respectively.

Few risk factors are:

• immobilization 
• prolonged hospitalization
• recent surgery
• trauma 
• obesity
• malignancy
• previous history
• oral contraceptives/hormone replacement therapy
• pregnancy
• postpartum status
• family history
• heart failure
• inflammatory bowel disease
• collagen-vascular disease
• myeloproliferative disorders
• nephrotic syndrome
• heparin-induced thrombocytopenia (HIT)
• liver disease

#vascular

#hematology

#clinical-exam

References:

1. Sandler DA, Martin JF, Duncan JS, et al. Diagnosis of deep-vein thrombosis: comparison of clinical evaluation, ultrasound, plethysmography, and venoscan with X-ray venogram. Lancet 1984; 2:716.

2. Kahn SR, Joseph L, Abenhaim L, Leclerc JR. Clinical prediction of deep vein thrombosis in patients with leg symptoms. Thromb Haemost 1999; 81:353.

PSH

Q: All of the following may occur in Paroxysmal Sympathetic Hyperactivity (PSH) in patients with traumatic brain injury (TBI) EXCEPT? (select one)

A) tachycardia

B) hypertension

C) hyperthermia

D) dry skin

E) increased muscle tone

Answer: D

Due to its dramatic presentation, there have been many names for this phenomenon commonly observed in neuro-ICUs among TBI patients such as autonomic storms, sympathetic storms, hypothalamic dysregulation syndrome, dysautonomia, paroxysmal autonomic instability with dystonia, and diencephalic autonomic epilepsy (misnomer). But in 2014, it was decided in a consensus conference to name it as paroxysmal sympathetic hyperactivity (PSH).

It is a dysregulation syndrome of autonomic function and presents as recurrent episodes of excessive sympathetic activity, may induced by stimulation, and resolve spontaneously though medications may expedite its resolution. But, if left untreated, may continue to cause further brain injury. Most of the time it may not require any workup such as STAT CT.

It usually manifests as an episode of tachycardia, hypertension, tachypnea, hyperthermia, sweating, and/or increased muscle tone with possible dystonic posturing.

#neuro-critical-care

#neurology

#trauma

References:

1. Meyfroidt G, Baguley IJ, Menon DK. Paroxysmal sympathetic hyperactivity: the storm after acute brain injury. Lancet Neurol 2017; 16:721.

2. Hughes JD, Rabinstein AA. Early diagnosis of paroxysmal sympathetic hyperactivity in the ICU. Neurocrit Care 2014; 20:454.

3. Baguley IJ, Perkes IE, Fernandez-Ortega JF, et al. Paroxysmal sympathetic hyperactivity after acquired brain injury: consensus on conceptual definition, nomenclature, and diagnostic criteria. J Neurotrauma 2014; 31:1515.

Vasoconstrictor extravasation

Q: 44 years old female is admitted to ICU with urosepsis. Norepinephrine (NE) ion is started in Emergency Department (ED) via peripheral IV. On arrival to ICU, it was noted that peripheral IV was not functional, and there was a significant amount of NE extravasated in underlying tissues. What is your next step?

Answer: Apply PHENTOLAMINE

PHENTOLAMINE is the antidote for vasoconstrictor extravasation in skin and tissues (dopamine, epinephrine, or norepinephrine). Infiltrate 5-15 mg of PHENTOLAMINE in 10 ml of normal saline into the area of extravasation as soon as possible. Treatment may be applied and effective up to 12 hours post extravasation of vasoconstrictor. Patient might develop transient hypotension post phentolamine application but responds well to fluid bolus.

Mechanism of action: Phentolamine is a nonspecific alpha-adrenergic blocking agent that inhibits vasoconstriction and improves blood circulation through the affected area.

If phentolamine is unavailable, a combination of subcutaneous terbutaline, a selective beta2 agonist, and topical nitroglycerin can be applied.

#toxicity

#pharmacology

References: 

1. Bey D, El-Chaar GM, Bierman F, Valderrama E. The use of phentolamine in the prevention of dopamine-induced tissue extravasation. J Crit Care. 1998 Mar;13(1):13-20. doi: 10.1016/s0883-9441(98)90024-7. PMID: 9556122.

2. Plum M, Moukhachen O. Alternative Pharmacological Management of Vasopressor Extravasation in the Absence of Phentolamine. P T. 2017 Sep;42(9):581-592. PMID: 28890646; PMCID: PMC5565133.

Splenic injury in patients with portal hypertension

Q: 43 years old male with a known history of advanced cirrhosis and portal hypertension is admitted to ICU after a Motor Vehicle Accident (MVA). CT scan consists of Grade V spleen laceration. There is a conflict between the two teams regarding operative vs. nonoperative management. The ICU team suggests embolization via Interventional Radiology (non-operative approach), but the surgical team suggests splenectomy. Which approach seems appropriate for this patient? (select one)

A) operative

B) non-operative

Answer: A

Portal hypertension is a relative contraindication to nonoperative management of splenic injury. This is due to the evidence that increased venous pressures may prevent clot formation and control of hemorrhage even after successful splenic embolization. 

Patients with advanced cirrhosis and high Model for End-stage Liver Disease (MELD) score usually have high complications after a non-operative approach in splenic injury. Any patient with hemodynamic instability, generalized peritonitis, or for patients with other intra-abdominal injuries usually needs a surgical approach.

Given the highest grade of splenic injury and underlying advanced portal hypertension, this patient has a better chance of survival with splenectomy.

#trauma

#surgical-critical-care

References:

1. Stassen NA, Bhullar I, Cheng JD, et al. Nonoperative management of blunt hepatic injury: an Eastern Association for the Surgery of Trauma practice management guideline. J Trauma Acute Care Surg 2012; 73:S288.

2. Bugaev N, Breeze JL, Daoud V, et al. Management and outcome of patients with blunt splenic injury and preexisting liver cirrhosis. J Trauma Acute Care Surg 2014; 76:1354.

3. Cook MR, Fair KA, Burg J, et al. Cirrhosis increases mortality and splenectomy rates following splenic injury. Am J Surg 2015; 209:841.

On anti-smoking treatment

Q: 52 years old male with history of coronary artery disease (CAD), hypertension (HTN) and childhood seizures is admitted to ICU with status epilepticus. Patient was recently started on anti-smoking treatment by his primary care physician. Which of the following is the probable cause? (select one)

A) Nicotine Replacement Therapy (NRT) 

B) Varenicline

C) Bupropion

D) Vaping

Answer: C

Bupropion reduces the seizure threshold. Although it has been used as an anti-smoking treatment it carries the risk of seizure particularly in patient with seizure history.

NRT is also a common method applied against smoking but because of its  adrenergic and vasoconstrictive properties, it is usually avoided in patients with CAD and HTN.

Varenicline is a good choice in patients with multiple comorbidities like CAD, HTN or seizures.

Vaping is considered even worse than cigarette smoking and should be avoided at all cost.

#neurology

#cardiology

#preventive-medicine

#pharmacology

References:

1. Barua RS, Rigotti NA, Benowitz NL, et al. 2018 ACC Expert Consensus Decision Pathway on Tobacco Cessation Treatment: A Report of the American College of Cardiology Task Force on Clinical Expert Consensus Documents. J Am Coll Cardiol 2018; 72:3332.

2. Meine TJ, Patel MR, Washam JB, et al. Safety and effectiveness of transdermal nicotine patch in smokers admitted with acute coronary syndromes. Am J Cardiol 2005; 95:976.

3. Eisenberg MJ, Windle SB, Roy N, et al. Varenicline for Smoking Cessation in Hospitalized Patients With Acute Coronary Syndrome. Circulation 2016; 133:21.

4. Eisenberg MJ, Grandi SM, Gervais A, et al. Bupropion for smoking cessation in patients hospitalized with acute myocardial infarction: a randomized, placebo-controlled trial. J Am Coll Cardiol 2013; 61:524.

Pulseox and transport

Q: People getting transported in an ambulance may have falsely ____________ pulse-oximetry (pulseox) level?

A) high

B) low

Answer: B

The objective of the question is to highlight the phenomenon of 'signal-to-noise ratio' in pulseox reading. Any motion or noise artifact tends to decrease the proper signally of pulse-ox and falsely lowers the pulseox reading. Following are a few common situations:

• shivering
• seizure activity
• pressure on the sensor
• transport (ambulance or helicopter)

It can be easily detected by an erratic and 'not normal' pulseox waveform. One of the remedies is to apply a newer pulseox probe, which may be less affected by noise or motion.

#oxygenation

References:

1. Grace RF. Pulse oximetry. Gold standard or false sense of security? Med J Aust 1994; 160:638.

2. Ortega R, Hansen CJ, Elterman K, Woo A. Videos in clinical medicine. Pulse oximetry. N Engl J Med 2011; 364:e33.

3. Barker SJ. "Motion-resistant" pulse oximetry: a comparison of new and old models. Anesth Analg 2002; 95:967.

4. Gehring H, Hornberger C, Matz H, et al. The effects of motion artifact and low perfusion on the performance of a new generation of pulse oximeters in volunteers undergoing hypoxemia. Respir Care 2002; 47:48.

Orthostatic hypotension - quantification

Q: 72 years old male is transferred from ward/floor to ICU after an episode of hypotension, dizziness, fall, and hip fracture. Patient was admitted two days ago with an exacerbation of his baseline asthma. He was also started on an antihypertensive a day ago by the Hospital Medicine service. The diagnosis of orthostatic hypotension is made. Orthostatic hypotension is defined quantitatively as a drop in systolic blood pressure by? (select one)

A) At least by 10 mmHg fall

B) At least by 20 mmHg fall 

Answer: B

Orthostatic hypotension, also known as postural hypotension is common in patients who are on anti-hypertensive meds, particularly on initiation in older patients. This accounts for a large number of patients with injury risk due to falls. Data shows that antihypertensive treatment in older patients is associated with an increased risk of hip fracture during the first 8 weeks after the start of therapy. Orthostatic hypotension is defined as when, within two minutes of quiet standing, one or more occurs:

• At least a 20 mmHg fall in systolic blood pressure
• At least a 10 mmHg fall in diastolic blood pressure
• Symptoms of cerebral hypoperfusion, such as dizziness

#hemodynamics

#cardiology

References:

1. Tinetti ME, Han L, Lee DS, et al. Antihypertensive medications and serious fall injuries in a nationally representative sample of older adults. JAMA Intern Med 2014; 174:588.

2. Butt DA, Mamdani M, Austin PC, et al. The risk of hip fracture after initiating antihypertensive drugs in the elderly. Arch Intern Med 2012; 172:1739.

early paracentesis

Q: 44 years old homeless man with no previous medical record is brought to ICU with encephalopathy. On examination patient is found to have moderate ascites, probably due to alcoholic cirrhosis. Early paracentesis on admission is found to decrease mortality rate.

A) True

B) False

Answer: A

Although sometimes diagnosis may be apparent like patient in this question, the objective of the question is to emphasize that performing early paracentesis in patients with ascites may decrease mortality rates. This evidence comes from a study of about 18,000 patients with cirrhosis and ascites who were admitted to the hospital with a principle diagnosis of ascites or encephalopathy. The patients who received paracentesis had lower in-hospital mortality rates (adjusted odds ratio 0.55).

This is due the fact that, this not only confirms the apparent cause of ascites but may identify unexpected diagnoses.

#procedures

Reference:

Orman ES, Hayashi PH, Bataller R, Barritt AS 4th. Paracentesis is associated with reduced mortality in patients hospitalized with cirrhosis and ascites. Clin Gastroenterol Hepatol 2014; 12:496.

Linezolid and Thrombocytopenia

Q: 76 year old female is admitted from Nursing Home with severe Vancomycin resistant Enterococcus (VRE) pressure ulcer cellulitis. Linezolid is started by infectious diseases (ID) service. ICU fellow is worried about development of thrombocytopenia due to concurrent sepsis. What is the time lag between Linezolid initiation and Thrombocytopenia?

Answer: On average 7-14 days 

Thrombocytopenia could be multifactorial in ICU. One of the causes is Linezolid (Zyvox). But, thrombocytopenia with linezolid usually doesn't occur right away, and take up to 1-2 weeks with the initiation of treatment and could help in ruling out at least one reason. 

Relatively overall its mild, reversible and due to myelosuppression. There is no evidence for any anti-platelet mechanism or interference with platelet function. Said that one article in recent literature from machine learning, without clinical testing, claims to increase mortality and ICU Length of Stay (LOS).

#hematology

#ID

#pharmacology

References: 

1. Green SL, Maddox JC, Huttenbach ED. Linezolid and Reversible Myelosuppression. JAMA. 2001;285(10):1291. doi:10.1001/jama.285.10.1291

2. Takahashi Y, Takesue Y, Nakajima K, Ichiki K, Tsuchida T, Tatsumi S, Ishihara M, Ikeuchi H, Uchino M. Risk factors associated with the development of thrombocytopenia in patients who received linezolid therapy. J Infect Chemother. 2011 Jun;17(3):382-7. doi: 10.1007/s10156-010-0182-1. Epub 2010 Dec 3. PMID: 21127934.

3. Giunio-Zorkin N, Brown G. Real-Life Frequency of New-Onset Thrombocytopenia during Linezolid Treatment. Can J Hosp Pharm. 2019 Mar-Apr;72(2):133-138. Epub 2018 Apr 30. PMID: 31036974; PMCID: PMC6476580.

4. Maray I, Rodríguez-Ferreras A, Álvarez-Asteinza C, Alaguero-Calero M, Valledor P, Fernández J. Linezolid induced thrombocytopenia in critically ill patients: Risk factors and development of a machine learning-based prediction model. J Infect Chemother. 2022 Sep;28(9):1249-1254. doi: 10.1016/j.jiac.2022.05.004. Epub 2022 May 14. PMID: 35581121.

prone positioning - MOA

Q: 42 years old male is admitted to ICU with severe acute pancreatitis and developed severe ARDS. Prone positioning for 18 hours a day was initiated, while transfer to higher level of care can be arranged for the ECMO. 

Prone position ___________  the ventral alveolar overinflation? (select one)

A) decreases

B) increases

Answer: A

Prone positioning improves oxygenation via two mechanisms.

1. As patient lies prone on his chest, it decreases the ventral alveolar overinflation, and simultaneously dorsal alveolar collapse. This leads to the reduction in the difference between the dorsal and ventral transpulmonary pressure (Ptp). This makes ventilation more homogeneous in lung fields. This reduced alveolar distension limits ventilator-associated lung injury from overdistention and cyclic atelectasis.

2. Prone ventilation also opens alveoli that usually collapsed in the supine position. This also improves oxygenation. Fortunately, with the application of positive end expiratory pressure (PEEP), most patients sustain dorsal alveoli open during supine periods of prone positioning.

#ventilators

#pulmonary

References:

1. Douglas WW, Rehder K, Beynen FM, et al. Improved oxygenation in patients with acute respiratory failure: the prone position. Am Rev Respir Dis 1977; 115:559.

2. Lai-Fook SJ, Rodarte JR. Pleural pressure distribution and its relationship to lung volume and interstitial pressure. J Appl Physiol (1985) 1991; 70:967.

3. Cornejo RA, Díaz JC, Tobar EA, et al. Effects of prone positioning on lung protection in patients with acute respiratory distress syndrome. Am J Respir Crit Care Med 2013; 188:440.

Phosphate and refeeding syndrome

Q: Malnourished patients should be considered at high risk of 'refeeding syndrome' if they have consistent? (select one)

A) hypophosphatemia

B) hyperphosphatemia

Answer: A

In patients who are malnourished and are getting started on nutrition, enteral or parenteral, should be watched closely if their lab work shows hypokalemia and/or hypophosphatemia.

This is important as these patients stay at high risk for 'refeeding syndrome' despite concurrent supplementation. 

#nutrition

References:

1. Marinella MA. Refeeding syndrome and hypophosphatemia. J Intensive Care Med. 2005 May-Jun;20(3):155-9. doi: 10.1177/0885066605275326. PMID: 15888903.

2. Skipper A. Refeeding syndrome or refeeding hypophosphatemia: a systematic review of cases. Nutr Clin Pract. 2012 Feb;27(1):34-40. doi: 10.1177/0884533611427916. PMID: 22307490.

3. Fuentebella J, Kerner JA. Refeeding syndrome. Pediatr Clin North Am. 2009 Oct;56(5):1201-10. doi: 10.1016/j.pcl.2009.06.006. PMID: 19931071.

Fentanyl in intubation

Q: What is the optimum time to give Fentanyl before intubation to attenuate circulatory responses to laryngoscopy and tracheal intubation?

Answer: About 5 minutes

Laryngoscopy and tracheal intubation are usually accompanied by increases in arterial blood pressure and heart rate. Various methods have been suggested to attenuate these responses, including a beneficial effect of fentanyl.

Fentanyl, at a dose of 2 mcg/kg given 5 minutes before intubation, most effectively attenuated the increases in all four circulatory variables (Heart Rate, Systolic Arterial Pressure, Diastolic Arterial Pressure, and Mean Arterial Pressure).

#procedures

#pharmacology

References:

1. Small-Dose Fentanyl: Optimal Time of Injection for Blunting the Circulatory Responsesto Tracheal Intubation - Anesth Analg 1998;86:658-61

2. Adachi YU, Satomoto M, Higuchi H, Watanabe K. Fentanyl attenuates the hemodynamic response to endotracheal intubation more than the response to laryngoscopy. Anesth Analg. 2002 Jul;95(1):233-7, table of contents. doi: 10.1097/00000539-200207000-00043. PMID: 12088976.

3. Sawano Y, Miyazaki M, Shimada H, Kadoi Y. Optimal fentanyl dosage for attenuating systemic hemodynamic changes, hormone release and cardiac output changes during the induction of anesthesia in patients with and without hypertension: a prospective, randomized, double-blinded study. J Anesth. 2013 Aug;27(4):505-11. doi: 10.1007/s00540-012-1552-x. Epub 2013 Jan 12. PMID: 23314694.

CVC in previous pneumonectomy

Scenario: 57 year old male with previous history of Right pneumonectomy requires central venous line. Which would be your site of choice? (select one)

A) Left Internal Jugular 

B) Left Subclavian

C) Right Femoral

Answer: C

 Any site except left internal jugular (L-IJ) or left subclavian (L-SC) should be OK.

Patient already has Right pneumonectomy and if develops pneumothorax on left side, would be dead without any lungs - see CXR below.

whole-body CT scan after code blue

Q: Data/evidence favors whole-body CT scan after code blue?

A) True

B) False

Answer: A

Head-to-pelvis CT scan, popularly known as 'whole-body CT', after cardiac arrest, in particular out-of-hospital cardiac arrest shows benefit in identify both CPR-related trauma and the underlying etiology of the arrest. This can be very valuable in recognizing time-urgent complications, if there is a solid organ injury and in particular occult pneumothorax. It also helps to identify rib and sternal fractures.

Such scan should be performed (only and only) if patient is clinically stable to travel to CT suit post-code. Also, this should not hamper life-saving procedures such as cardiac angiography for ST elevation myocardial infarction.

#cardiology

#trauma

#code-blue

#hemodynamics

#radiology

References:

1. Branch KRH, Strote J, Gunn M, et al. Early head-to-pelvis computed tomography in out-of-hospital circulatory arrest without obvious etiology. Acad Emerg Med 2021; 28:394.

2. Karatasakis A, Sarikaya B, Liu L, et al. Prevalence and Patterns of Resuscitation-Associated Injury Detected by Head-to-Pelvis Computed Tomography After Successful Out-of-Hospital Cardiac Arrest Resuscitation. J Am Heart Assoc 2022; 11:e023949.

vitamin level in status epilepticus

Q: Which of the following vitamin levels is suggested to be checked in a patient with status epilepticus? (select one)

A) Vitamin B6

B) vitamin B12

Answer: A

It is observed that patients with low or low-normal pyridoxine (vitamin B6) levels are prone to stay in status epilepticus. 

Other investigations which are suggested are serum glucose, serum electrolytes, calcium, phosphorus, magnesium, liver function tests (LFTs), complete blood count (CBC), serum anti-seizure medications level (if the patient is on it), urine and blood toxicology, pregnancy test (in reproductive age female patients), lactate and troponin level.

#neurology

References:

1. Dave HN, Eugene Ramsay R, Khan F, et al. Pyridoxine deficiency in adult patients with status epilepticus. Epilepsy Behav 2015; 52:154.

2. Hocker S, Prasad A, Rabinstein AA. Cardiac injury in refractory status epilepticus. Epilepsia 2013; 54:518.

statin-induced myopathy and thyroid

Q: Which of the following is more prone to statin-induced myopathy? (select one)

A) Hyperthyroidism

B) Hypothyroidism

Answer: B

It is a common practice to check liver enzymes prior to starting statin, but ideally, thyroid-stimulating hormone (TSH) level should also be checked prior to initiating statin therapy, as hypothyroidism itself is a potential cause of dyslipidemia, and may predispose to statin-induced myopathy. 

This suggests that the use of statins may "unmask" the underlying subclinical hypothyroid myopathy.

#endocrinology

#pharmacology

References:

1. Bar SL, Holmes DT, Frohlich J. Asymptomatic hypothyroidism and statin-induced myopathy. Can Fam Physician 2007; 53:428.

2. Lando HM, Burman KD. Two cases of statin-induced myopathy caused by induced hypothyroidism. Endocr Pract 2008; 14:726.

3. al-Jubouri MA, Briston PG, Sinclair D, et al. Myxoedema revealed by simvastatin induced myopathy. BMJ 1994; 308:588.

4.Scalvini T, Marocolo D, Cerudelli B, et al. Pravastatin-associated myopathy. Report of a case. Recenti Prog Med 1995; 86:198.