Monday, August 20, 2018

POUR

Q: Urinary bladder distension in ICU may cause? (select one)

A) Tachycardia
B) Bradycardia
C) Both (either)


Answer:   C 

With pain of bladder distension tachycardia is expected but any visceral distention like of bowels or urinary bladder may cause a symptomatic bradycardia due to vagal reflex. 

Typically known as POUR (postoperative urinary retention), is usually a transient phenomenon but may stay for a significant period of time to cause hemodynamic instability. Age, gender (male), drugs, type of anesthesia, underlying neurologic diseases are well-known risk factors. Beside urologic or bowel surgery, it may be of interest to know that joint arthroplasty is another risk factor. One time bladder catheterization (straight cath) should be performed if bladder scan determines >600 mL of urine. 

#surgicalcriticalcare
#urology



 Reference: 

Baldini G, Bagry H, Aprikian A, Carli F. Postoperative urinary retention: anesthetic and perioperative considerations. Anesthesiology 2009; 110:1139.

Sunday, August 19, 2018

4 to 5 minutes rule of maternal code blue

Q: If a pregnant patient has a cardiac arrest and the uterine fundus is noted to be at or above the umbilicus, perimortem cesarean should be initiated at?

A) Two minutes
B) Four minutes
C) Eight minutes
D) Fifteen minutes
E) Only if there is an unsuccessful code 



Answer: B

If a pregnant patient has a cardiac arrest, it should be announced as "maternal code blue" so the obstetrical and neonatology teams can arrive at the initiation of code and can start preparing for cesarean delivery. It is recommended to have a person with a dedicated timer, and the procedure should begin at four minutes if ACLS protocol stays unsuccessful and the baby should be delivered by the end of the five minutes.


 During ACLS of a pregnant patient, if the uterus is at or above the umbilicus, it should be manually displaced to the left lateral position, while CPR is performed. Another important aspect to remember is to place intravenous (IV) access above the diaphragm. 

Actually, early delivery is associated with a successful outcome of the resuscitation process itself.

#ob-gyn
#cardiology


References:

1. Rose CH, Faksh A, Traynor KD, et al. Challenging the 4- to 5-minute rule: from perimortem cesarean to resuscitative hysterotomy. Am J Obstet Gynecol 2015; 213:653.

2. Doan-Wiggins L. Resuscitation of the pregnant patient suffering death. In: Cardiac Arrest: the science and practice of resuscitation medicine, Turrentine MA, Braems G, Ramirez MM (Eds), Williams and Wilkins, Philadelphia 1997. p.812.

Saturday, August 18, 2018

prediction of resolution of constrictive pericarditis

Q: Resolution of constrictive pericarditis can be predicted even before any treatment is given? (select one)

A) True
B) False


Answer: A (True)

With the advent of Cardiac Magnetic Resonance (CMR), resolution of the constrictive pericarditis can be predicted even before any anti-inflammatory treatment is given. It can be predicted by the degree of late gadolinium enhancement (LGE) of the pericardium. Patients with tendency to have transient constrictive pericarditis have greater baseline LGE pericardial thickness and greater LGE qualitative intensity. LGE with pericardial thickness ≥3 mm predicted reversibility of constriction with 86 percent sensitivity and 80 percent specificity.

#cardiology
#radiology



Reference:

Feng D, Glockner J, Kim K, et al. Cardiac magnetic resonance imaging pericardial late gadolinium enhancement and elevated inflammatory markers can predict the reversibility of constrictive pericarditis after antiinflammatory medical therapy: a pilot study. Circulation 2011; 124:1830.

Friday, August 17, 2018

diabetic thoracic radiculopathy

Q: 58 year old male with a past medical history (PMH) of hypertension (HTN), Diabetes Mellitus (DM), Chronic Kidney Disease (CKD)-3 and coronary artery disease (CAD) with previous stents is admitted to ICU with chest pain. EKG seems unchanged from previous. First two troponins are negative. The patient described his chest pain different from previous as more sharp and burning. On examination, the patient found to have abdominal wall herniation. The patient will probably respond best to?

A) Nitroglycerine infusion
B) IV morphine
C) Gabapentin
D) Nonsteroidal Anti-inflammatory Drugs (NSAIDs)
E) Physical Therapy


Answer: C

Patient has diabetic thoracic radiculopathy, which can be very confusing in patients with poorly controlled diabetes and other underlying diseases. Chest pain is usually described differently as severe, sharp, and/or burning type. Many patients may develop abdominal muscle weakness and herniation. Fortunately, it is easy to treat and respond very well to gabapentin (dose up to 1200 mg three times daily). Non-responders may respond to 100 mg daily dose of nortriptyline or a course of  60 mg daily (divided) dose of oral prednisone.

Choice D is contra-indicated in this patient with underlying kidney disease. Physical therapy may help but it is not the first line of treatment. Nitroglycerine and morphine are not required as this is not the chest pain of cardiac origin.


#endocrinology
#neurology
#musculoskeletal


Reference:

Sun SF, Streib EW. Diabetic thoracoabdominal neuropathy: clinical and electrodiagnostic features. Ann Neurol 1981; 9:75. Chaudhuri KR, Wren DR, Werring D, Watkins PJ. Unilateral abdominal muscle herniation with pain: a distinctive variant of diabetic radiculopathy. Diabet Med 1997; 14:803.


Thursday, August 16, 2018

Purtscher retinopathy

Q: What is Purtscher retinopathy? 


Answer: 

Purtscher retinopathy is a sudden decreased vision due to superficial retinal hemorrhages or cotton wool spots encircling the optic nerve. It can occur without any direct injury to the eye and can be seen in various diseases encountered in a critical care setting (see a long list of references below) like traumatic compression of the legs, chest or head, acute pancreatitis, amniotic fluid embolization, preeclampsia, HELLP syndrome and lupus. The exact mechanism is not clear but it appears to be leukoembolization, arterial occlusion, and infarction of the retinal microvascular bed, either due to fat embolization or leukocyte aggregation induced by complement C5a.

#opthalmology
#trauma
#vasculitis
#gastroenterology
#ob-gyn



References:

1. Agrawal A, McKibbin MA. Purtscher's and Purtscher-like retinopathies: a review. Surv Ophthalmol. 2006 Mar-Apr. 51(2):129-36.


2. Bhan K, Ashiq A, Aralikatti A, Menon KV, McKibbin M. The incidence of Purtscher retinopathy in acute pancreatitis. Br J Ophthalmol. 2008 Jan. 92(1):151-3. 


3. Sauer A, Nasica X, Zorn F, Petitjean P, Bader P, Speeg-Schatz C, et al. Cryoglobulinemia revealed by a Purtscher-like retinopathy. Clin Ophthalmol. 2007 Dec. 1 (4):555-7. 


4. Okwuosa TM, Lee EW, Starosta M, Chohan S, Volkov S, Flicker M, et al. Purtscher-like retinopathy in a patient with adult-onset Still's disease and concurrent thrombotic thrombocytopenic purpura. Arthritis Rheum. 2007 Feb 15. 57 (1):182-5


5. Dyrda A, Matheu Fabra A, Aronés Santivañez JR, Blanch Rubio J, Alarcón Valero I. Purtscher-like retinopathy as an initial presentation of iron-deficiency anaemia. Can J Ophthalmol. 2015 Feb. 50 (1):e1-2.

6. Landes A, Jay WM. Purtscher-like retinopathy in a patient with preeclampsia. Seminars in Ophthalmology. 2009. 24:217-220. 

7. Blodi BA, Johnson MW, Gass JD, Fine SL, Joffe LM. Purtscher's-like retinopathy after childbirth. Ophthalmology. 1990 Dec. 97(12):1654-9. 

8. Stewart MW, Brazis PW, Guier CP, Thota SH, Wilson SD. Purtscher-like retinopathy in a patient with HELLP syndrome. Am J Ophthalmol. 2007 May. 143(5):886-7. 

9. Chandra P, Azad R, Pal N, Sharma Y, Chhabra MS. Valsalva and Purtscher's retinopathy with optic neuropathy in compressive thoracic injury. Eye. 2005 Aug. 19(8):914-5. 

10. Chang M, Herbert WN. Retinal arteriolar occlusions following amniotic fluid embolism. Ophthalmology. 1984 Dec. 91(12):1634-7. 

11. Cooper BA, Shah GK, Grand MG. Purtscher's-like retinopathy in a patient with systemic lupus erythematosus. Ophthalmic Surg Lasers Imaging. 2004 Sep-Oct. 35(5):438-9.

12. Shah GK, Penne R, Grand MG. Purtscher's retinopathy secondary to airbag injury. Retina. 2001. 21(1):68-9. 

Wednesday, August 15, 2018

Bilirubinuria

Q: Bilirubinuria (bilirubin in the urine) reflects? (select one) 

 A) Conjugated bilirubinemia 
B) Unconjugated bilirubinemia


Answer: A

Unconjugated bilirubin is tightly bound to albumin and is not present in the urine. Presence of bilirubin in the urine indicates conjugated bilirubinemia and probable hepatobiliary disease process. 


Clinical significance: Bilirubinuria can exist with normal serum  conjugated bilirubin as reabsorptive capacity of kidney for conjugated bilirubin is low, and it can be an early sign of liver disease.

#hepatology

Reference: 

KLATSKIN G, BUNGARDS L. An improved test for bilirubin in urine. N Engl J Med 1953; 248:712.

Tuesday, August 14, 2018

"afterdrop"

Q: What is "afterdrop" during cardiopulmonary bypass (CPB)?



Answer: 

Most patients drop their core temperature after rewarming from hypothermic CPB and is known as "afterdrop".

It can be avoided by adequate rewarming before separation from CPB, and other measures such as increasing the room temperature, warming blood products and IV fluids and the use of a humidifier in ventilators. Hypothermia can have its own consequences with coagulopathy and platelet dysfunction.

#surgicalcriticalcare


References: 

Tindall MJ, Peletier MA, Severens NM, et al. Understanding post-operative temperature drop in cardiac surgery: a mathematical model. Math Med Biol 2008; 25:323.

Monday, August 13, 2018

Myxedema Coma

Q: All of the following are the signs and symptoms of myxedema coma except?

A) Hypernatremia 

B) Hypothermia 
C) Hypoventilation 
D) Hypoglycemia
E) Bradycardia


Answer: A

Myxedema coma causes hyponatremia in most of the patients. This is due to impairment of free water excretion due to inappropriate excess vasopressin secretion. Also impaired renal function and adrenal insufficiency plays a part. Treatment is to reverse hypothyroidism with thyroid replacement supported with steroid with mineralocorticoid activity. Simple mnemonic to remember treatment regimen of myxedema coma is 

R = Rewarming 
I = Isotonic Saline
T = Thyroid replacement
S = Steroid 


#endocrinology
#electrolytes




References:


1. Iwasaki Y, Oiso Y, Yamauchi K, et al. Osmoregulation of plasma vasopressin in myxedema. J Clin Endocrinol Metab 1990; 70:534. 


2.  Popoveniuc G, Chandra T, Sud A, et al. A diagnostic scoring system for myxedema coma. Endocr Pract 2014; 20:808.


3. Jonklaas J, Bianco AC, Bauer AJ, et al. Guidelines for the treatment of hypothyroidism: prepared by the american thyroid association task force on thyroid hormone replacement. Thyroid 2014; 24:1670.

Sunday, August 12, 2018

Thrombosis in nephrotic syndrome

Q: 28 year old female with established diagnosis of nephrotic syndrome admitted to ICU with shortness of breath (SOB) and diagnosis of pulmonary embolism (PE). Work up showed hypoalbuminemia and renal vein thrombosis (RVT). What is the risk correlation between hypoalbuminemia and RVT?


Answer:  

The risk for arterial thrombosis, deep vein thrombosis (DVT) and renal vein thrombosis (RVT) gets proportionally high with the severity of the hypoalbuminemia. Once the serum albumin concentration is ≤2.8 g/dL, the risk starts to rise with a 2.13-fold increase for every 1 g/dL decrease in albumin below this level. 

Treatment consist as of any other acute thrombosis depending on the severity including anticoagulation, systemic or catheter based thrombolytic therapy or thrombectomy, followed by maintenance of warfarin therapy with INR goal of 2-3.

#nephrology
#hematology



Reference:

1. Lionaki S, Derebail VK, Hogan SL, et al. Venous thromboembolism in patients with membranous nephropathy. Clin J Am Soc Nephrol 2012; 7:43.


2. Weger N, Stawicki SP, Roll G, et al. Bilateral renal vein thrombosis secondary to membraneous glomerulonephritis: successful treatment with thrombolytic therapy. Ann Vasc Surg 2006; 20:411.



3. Dupree LH, Reddy P. Use of rivaroxaban in a patient with history of nephrotic syndrome and hypercoagulability. Ann Pharmacother 2014; 48:1655.

Saturday, August 11, 2018

Blood warmer in blood product transfusions

Q: Use of blood warmer is preferred during transfusion of all of the following blood products except? (select one)

A) RBC units 

B) Plasma products 
C) Cryoprecipitate 
D) Platelets 
E) C & D


Answer: E

Use of blood warmer is highly recommonded during transfusion of cold and previously thawed blood products including pRBC and fresh frozen plasma (FFP). Transfusion without blood warmer may induce clinically significant hypothermia causing coagulopathy. Cryoprecipitate is required to be thawed to room temperature and does not requires blood warmer (choice C). Also, platelets are stored at room temperature and use of blood warmer is not necessary (choice D) 2.

#hematology



References: 

1. Madrid E, Urrútia G, Roqué i Figuls M, et al. Active body surface warming systems for preventing complications caused by inadvertent perioperative hypothermia in adults. Cochrane Database Syst Rev 2016; 4:CD009016.

2. Konig G, Yazer MH, Waters JH. Stored platelet functionality is not decreased after warming with a fluid warmer. Anesth Analg 2013; 117:575.

Friday, August 10, 2018

Bactrim in patients with Cystic Fibrosis

Q: The dose of oral trimethoprim-sulfamethoxazole (Bactrim) in patients with Cystic Fibrosis (CF) should be adjusted to? (select one) 

 A) Increase the dose 
B) Decrease the dose 


Answer: A

The dose of oral trimethoprim-sulfamethoxazole in patients with Cystic fibrosis need to be increased by almost 50 percent. This is due to the fact that hepatic clearance of sulfamethoxazole is increased in these patients due to accelerated acetylation. Also, clearance of trimethoprim via kidney gets enhanced. The reason for this renal effect is not clear.

#pharmacology



Reference:

Reed MD, Stern RC, Bertino JS Jr, et al. Dosing implications of rapid elimination of trimethoprim-sulfamethoxazole in patients with cystic fibrosis. J Pediatr 1984; 104:303.

Thursday, August 9, 2018

Malignant Hyperthermia and Neuroleptic malignant syndrome

Q: Which of the following statement(s) is/are true? (Select one)

A) Malignant Hyperthermia (MH) in the postoperative period is extremely rare
B) Neuroleptic malignant syndrome (NMS) is usually of slow onset
C) Usually, clinical signs of MH occurs within one hour of anesthesia induction
D) NMS usually does not occur during administration of general anesthesia
E) All of the above


Answer: E

The objective of the above question is to highlight the major differentiating point between MH and NMS in view of their timings. MH is extremely rare in the postoperative period. Although it usually occurs within one hour of anesthesia induction but can occur any time during anesthesia due to triggering agent. In contrast, NMS may take up to 72 hours to clearly manifest and practically never occurs during administration of general anesthesia.

#pharmacology
#surgicalcriticalcare



References:

1. Velamoor VR, Norman RM, Caroff SN, et al. Progression of symptoms in neuroleptic malignant syndrome. J Nerv Ment Dis 1994; 182:168.

2.  Larach MG, Gronert GA, Allen GC, et al. Clinical presentation, treatment, and complications of malignant hyperthermia in North America from 1987 to 2006. Anesth Analg 2010; 110:498.

Wednesday, August 8, 2018

CXR pearl

Q: Equalization of blood vessels on CXR ( upper and basal vessels are equally dilated) occurs in all of the following except

A) left ventricular failure 
B) left-to-right shunts 
C) hyperthyroidism 
D) pregnancy 
E) anemia 


 Answer:  A

Meticulous reading of chest-X-ray (CXR) can provide valuable information on underlying disease. "Cephalization" on CXR means the upper lobe vessels are more dilated than the basal vessels is the hallmark of the diseases like left ventricular failure, mitral valve stenosis, basal emphysema or patients lying in recumbent patients. 

Similarly equalization or balanced flow is seen in hyperdynamic circulation as left-to-right shunts, hyperthyroidism, pregnancy, or anemia. 

#radiology
#pulmonary


Reference:


Ravin CE. Pulmonary vascularity: radiographic considerations. J Thorac Imaging 1988; 3:1.

Tuesday, August 7, 2018

Pupillary reflexes in NMBAs

Q: Which of the following Neuro-muscular blocking agent (NMBA) is unreliable in determining pupillary reflexes in ICU?

A) Cisatracurium
B) Pancuronium
C) Vecuronium
D) Succinylcholine
E) Rocuronium


Answer:  B

Patients who require NMBA use in ICU should be examined frequently for any change in neurological changes. The quick, reliable and easy way is to look for pupillary reactions. Although Pancuronium is not much of use in ICU due to its long recovery time, impaired metabolism in renal as well as hepatic dysfunction and significant accumulation, it may still be used in patients who require very long neuromuscular blocking as in severe ARDS.

Most of the NMBAs do not interfere with pupillary reflexes except for pancuronium due to its antimuscarinic effects.


#pharmacology


Reference:

Pancuronium bromide Injection [prescribing information]. Lake Forest, IL: Hospira, Inc; September 2010.

Monday, August 6, 2018

Remifentanil for mechanically ventilated patients

Q: Remifentanil has been advocated for use in mechanically ventilated patients for analgesia. What are the three main characteristics of this drug which make it superior to other continuous analgesia infusions in ICU? 


Answer: 


Remifentanil has been advocated for off-label use in ICU for mechanically ventilated patients
1 as a continuous infusion over fentanyl or morphine because of it's few characteristics which include.

1. ultrashort duration of action with the onset of action in 1-3 minutes, peak effect in 3-5 minutes and total duration of up to 10 minutes.

2. In patients with severe multiorgan failure, it has an advantage as its effect does not depend on renal or hepatic metabolism.

3. In patients with hemodynamic instability or bronchospasm, it has the advantage to release little histamine.

But, it should be used with caution in awake patients as may cause respiratory depression, and in patients with bradycardia. Also, if used with serotonergic agents, it may cause Serotonin syndrome. Also, it can elevate the intra-cranial pressure. 4


#pharmacology



References:

1. Dahaba AA, Grabner T, Rehak PH, et al. Remifentanil versus morphine analgesia and sedation for mechanically ventilated critically ill patients: a randomized double blind study. Anesthesiology 2004; 101:640.

2. Tan JA, Ho KM. Use of remifentanil as a sedative agent in critically ill adult patients: a meta-analysis. Anaesthesia 2009; 64:1342.

3.. Barr J, Fraser GL, Puntillo K, et al, “Clinical Practice Guidelines for the Management of Pain, Agitation, and Delirium in Adult Patients in the Intensive Care Unit,” Crit Care Med, 2013, 41(1):263-306.

4.  Warner DS, Hindman BJ, Todd MM, et al, “Intracranial Pressure and Hemodynamic Effects of Remifentanil Versus Alfentanil in Patients Undergoing Supratentorial Craniotomy,” Anesth Analg, 1996, 83(2):348-53. 

Sunday, August 5, 2018

Functions of Ileum

Q: When surgery of intestine is considered, which important function(s) of ileum should be considered? 

A) Vitamin B12 absorption 
B) Bile acid absorption 
C) "Ileal brake" 
D) Fluid absorption 
E) All of the above


Answer: E

When the resection of the intestine become inevitable for various reasons, being an ICU physician it may be of importance to know some very important functions of ileum while parenteral or enteral nutrition is considered postoperatively.

Out of all of the above, probably the most important to know is that the distal 50 cm of the ileum is the primary site for vitamin B12 absorption, as resection of the terminal ileum is very common in short bowel syndrome (SBS). It requires lifelong vitamin B12 supplementation. 

Second most important to know that the distal ileum is the 'selective site' for bile acids absorption, and need close observation for malabsorption of fat as well as fat-soluble vitamins. Another secondary effect of non-absorption of bile acid is the colonic secretomotor diarrhea. 1

 "Ileal brake" is an interesting and a less known concept. Unabsorbed lipids reaching the ileum cause a delay in gastric emptying which can be beneficial if residual ileum can be spared during the surgery. 2,3

Ileum has an active salt transport which facilitates the reabsorption of the fluid secreted by the jejunum. Also, it helps in the absorption of fluid entering the gut via hypertonic feedings. 4

#nutrition

#surgicalcriticalcare



References:

1. Hofmann AF, Poley JR. Role of bile acid malabsorption in pathogenesis of diarrhea and steatorrhea in patients with ileal resection. I. Response to cholestyramine or replacement of dietary long chain triglyceride by medium chain triglyceride. Gastroenterology 1972; 62:918. 

2. Welch IM, Cunningham KM, Read NW. Regulation of gastric emptying by ileal nutrients in humans. Gastroenterology 1988; 94:401. 

3. Van Citters GW, Lin HC. Ileal brake: neuropeptidergic control of intestinal transit. Curr Gastroenterol Rep 2006; 8:367.

4. Fordtran JS, Rector FC Jr, Carter NW. The mechanisms of sodium absorption in the human small intestine. J Clin Invest 1968; 47:884.  

Saturday, August 4, 2018

Propofol and PET scan

Q: Propofol should be discontinued in patients going for Positron Emission Tomography/Computed Tomography(PET) scan at least? (select one)

A) 48 hours prior
B) 24 hours prior
C) 6 hours prior
D) 30 minutes prior
E) It does not have any effect and can be continued 



Answer: D

Propofol interferes with fluorodeoxyglucose (FDG) uptake and should be discontinued at least 30 minutes prior to PET scan. Propofol depresses glucose disappearance from the blood stream without affecting plasma insulin secretion. This depression is induced by accumulating free fatty acid due to lipids in propofol infusion.

#pharmacology



Reference:

Zhongjin Y, Minji C, Ammar A, et al. (2017) Impact of Sevoflurane and Propofol Anesthesia on Quality of [18F] FDG-PET Scan Image. SOJ Anesthesiol Pain Manag. 4(2): 1-4.

Friday, August 3, 2018

Chlorhexidine bathing in ICUs

Q: Chlorhexidine bathing is superior to bathing with soap and water in ICUs? (select one)

A) True
B) False


Answer: A

Most of the studies have now established that bath/cleaning of patients with chlorhexidine-impregnated washcloths every day is superior to bathing with soap and water in ICUs. There are two major reasons behind it. First, it decreases the colonization of drug-resistant organisms. Second, (excess) water may be associated with an increased catheter exit-site infections. 4 Daily bathing with chlorhexidine also showed to decrease the line infections. 3

#infectiousdiseases



References:

1. O'Horo JC, Silva GL, Munoz-Price LS, Safdar N. The efficacy of daily bathing with chlorhexidine for reducing healthcare-associated bloodstream infections: a meta-analysis. Infect Control Hosp Epidemiol 2012; 33:257. 

2. Climo MW, Yokoe DS, Warren DK, et al. Effect of daily chlorhexidine bathing on hospital-acquired infection. N Engl J Med 2013; 368:533.

3. Montecalvo MA, McKenna D, Yarrish R, et al. Chlorhexidine bathing to reduce central venous catheter-associated bloodstream infection: impact and sustainability. Am J Med 2012; 125:505. 

4. Marchaim D, Taylor AR, Hayakawa K, et al. Hospital bath basins are frequently contaminated with multidrug-resistant human pathogens. Am J Infect Control 2012; 40:562. 

Thursday, August 2, 2018

Fire during cardioversion

Q: All of the following are true regarding electrical cardioversion except?

A) Oxygen saturation should be monitored
B) Intravenous access should be established
C) Cart for  advanced cardiac life support (ACLS) should be made available
D) Should be performed only by a physician
E) Supplemental oxygen (nasal cannula/venti-mask) should be transiently removed during application of shock


Answer: D

The objective of the above question is to point out the hazard of fire during electrical cardioversion. Any open access of oxygen like nasal cannula or venti-mask should be held for those seconds when a shock is applied for electrical cardioversion, so choice E is correct! The risk is higher if oxygen saturation > 50% and within 30 cm of the patient. Pausing the ventilator for few seconds while shock is applied has been mentioned but there is no concrete evidence to support this practice as ventilators usually have a closed circuit.

Electrical cardioversion can be performed by any person trained including nurses and midlevel providers.

#cardiology


Reference: 

1. ECRI Institute. Hazard report: using external defibrillators in oxygen-enriched atmospheres can cause fires. Health Devices 2005; 34: 423-425. 

2. American Heart Association Guidelines for CPR and ECC, 2005. Supplement to Circulation. 2005;112:IV-41.

Wednesday, August 1, 2018

Munchausen syndrome

Q: Factitious disorder (Munchausen syndrome) is characterized by all of the following except? 

 A) Higher in female gender 
B) Higher in married individuals 
C) Higher in healthcare workers 
D) Excellent verbal skills 
E) Possible positive findings on CT/MRI (neuro-imaging)


Answer: B

Factitious disorder is a psychiatric disorder characterized by a patient deceptively misrepresent an illness and/or injury even there is no financial reward.

The objective of above question is to emphasis that although factitious disorder is considered as a pure non-physiological state but recent  reports are pointing towards positive findings in brain, like disseminated white matter lesions on MRI, bilateral frontotemporal cortical atrophy on CT scan or hyperperfusion of the right thalamus on SPECT scan.

It is more common in unmarried individuals.

#psychiatry 



References:

1. Bass C, Halligan P. Factitious disorders and malingering: challenges for clinical assessment and management. Lancet 2014; 383:1422.

2. Pankratz L, Lezak MD. Cerebral dysfunction in the Munchausen syndrome. Hillside J Clin Psychiatry 1987; 9:195. 

3. Fénelon G, Mahieux F, Roullet E, Guillard A. Munchausen's syndrome and abnormalities on magnetic resonance imaging of the brain. BMJ 1991; 302:996. 

4. Babe KS Jr, Peterson AM, Loosen PT, Geracioti TD Jr. The pathogenesis of Munchausen syndrome. A review and case report. Gen Hosp Psychiatry 1992; 14:273. 

5. Mountz JM, Parker PE, Liu HG, et al. Tc-99m HMPAO brain SPECT scanning in Munchausen syndrome. J Psychiatry Neurosci 1996; 21:49.

Tuesday, July 31, 2018

K-Centra

Q: 4-Factors Prothrombin complex concentrate (Brand Name:Kcentra) contains all of the following except

A) Factors II
B) Factor VIII
C) Factor IX
D) Factor X
E) Protein C and Protein S


Answer: B

The objective of above question is to highlight the fact that despite it's name '4-Factors Prothrombin complex concentrate', it also contains Protein C and S.


'KCentra' contains  Factors II, VII (not VIII), IX and X.


#hematology



Reference:

Kcentra (prothrombin complex concentrate human) [prescribing information]. Kankakee, IL: CSL Behring; August 2017.

Monday, July 30, 2018

Decreasing "death rattle"

Q: All of the following are good options to decrease "death rattle" at the end of the life care except?

A) Glycopyrrolate 0.1 mg SL q 6 hours/PRN
B) Scopolamine transdermal 1.5 mg patch q 72 hours
C)) Atropine 0.4 to 0.6 mg SC q 4-6 hours/PRN
D) Atropine 1-2 drops 1% ophthalmic solution given SL q 2-4 hours/PRN
E) Epinephrine 0.5 mg SC q 4-6 hours/PRN


Answer:

"Death rattle" - sound from upper airway secretions are of distress to a patient as well as to the family. It may also increase the risk of pneumonia in a patient going through the last stages of life.  Before applying the pharmacologic treatment, it would be appropriate to provide emotional support, logical explanation, proper positioning, and cleaning the mouth.


All of the above pharmacological interventions are good options except choice E. Epinephrine has no role in such scenario, rather contra-indicated.

Indeed, choice D is interesting. 3


#palliativecare



References: 

1.  Bennett M, Lucas V, Brennan M, et al. Using anti-muscarinic drugs in the management of death rattle: evidence-based guidelines for palliative care. Palliat Med 2002; 16:369. 

2. Kintzel PE, Chase SL, Thomas W, et al. Anticholinergic medications for managing noisy respirations in adult hospice patients. Am J Health Syst Pharm 2009; 66:458. 

3. Protus BM. Evaluation of atropine 1% ophthalmic solution adminstered sublingually for the management of terminal respiratory secretions. Am J Hosp Palliat Care 2013; 30:388.

Sunday, July 29, 2018

electrical cardioversion for atrial fibrillation

Q: The success rate of electrical cardioversion for atrial fibrillation (AF) is inversely proportional to? (select one)

A) The size of the left atrium

B) The size of the right atrium


Answer: A

Overall, the success rate of electrical cardioversion for Atrial Fibrillation depends on two factors: 1) How long the AF is present (duration), and 2) the size of the left atrium. Moreover, the use of biphasic cardioversion works better than the use of monophasic cardioversion.

#cardiology



References:

1.  Lown B. Electrical reversion of cardiac arrhythmias. Br Heart J 1967; 29:469. 

2. Gurevitz OT, Ammash NM, Malouf JF, et al. Comparative efficacy of monophasic and biphasic waveforms for transthoracic cardioversion of atrial fibrillation and atrial flutter. Am Heart J 2005; 149:316. 

Saturday, July 28, 2018

Post-dural puncture headache

Q: All of the following are associated with a post-lumbar puncture (LP) headache or more accurately a post-dural puncture headache (PDPH) except

A) Female gender 
B) Pregnancy 
C) History of prior headaches 
D) High opening pressure 
E) Low body mass index (BMI) 


 Answer: D

Contrary to popular belief, the lower the opening pressure during LP the higher the risk of PDPH, as there is more chance of cerebrospinal (CSF) fluid hypotension which subsequently causes venous dilatation/congestion, the actual reason behind a headache. 


#neurology


Reference:

Vilming ST, Schrader H, Monstad I. The significance of age, sex, and cerebrospinal fluid pressure in post-lumbar-puncture headache. Cephalalgia 1989; 9:99.

Friday, July 27, 2018

Thyroid storm and calcium metabolism

Q: Thyroid storm is usually associated with? (select one)

A) Hypocalcemia
B) Hypercalcemia


Answer: B

Though not diagnostic but various biochemical abnormalities are supportive of suspected thyroid storm in patients with suppressed TSH and elevated T3 or/and T4. It includes hypercalcemia, abnormal liver enzymes, hyperglycemia, leukocytosis, or leukopenia. Hypercalcemia, as expected, is from hemoconcentration and increased bone resorption.

#endocrinology
#electrolytes


Reference:

Nayak B, Burman K. Thyrotoxicosis and thyroid storm. Endocrinol Metab Clin North Am 2006; 35:663.

Thursday, July 26, 2018

Complications of CRRT

Q: All of the following are the complications of Continuous Renal Replacement Therapy (CRRT) except?

A) Electrolyte imbalance
B) Acid-base imbalances
C) Hypotension
D) Infection
E) Hyperthermia



Answer:  E


There are many factors which lead to hypothermia during CRRT. About 150-200 mL of blood is staying outside the body at any given time. Also, replacement fluid and dialysate are at the bedside at room temperature. Rotation of such relatively larger volume contributes to hypothermia. Clinically, this induced hypothermia comes with its own price with clotting dysfunction 3, fibrinolysis, masking of infectious fever and in some cases arrhythmias.

Hypothermia can be avoided with the use of a blood warmer in the circuit but most systems have some type of plate or convective warmer for warming the therapy fluids. 4


#nephrology
#hypothermia



References:



1. Jones SK. Loss of body heat during continuous venovenous hemodialysis (CVVHD) in critically ill patients. Blood Purif. 2003; 21:183–207. 

2. Yagi N, LeBlanc M, Sakai K, Wright EJ, Paganini EP. Cooling effect of continuous renal replacement therapy in critically ill patients. Am J Kidney Dis. 1998;32:1023–1030.

3. Wolberg AS, Meng ZH, Monroe DM III, Hoffman M. A systemic evaluation of the effect of temperature on coagulation enzyme activity and platelet function. J Trauma. 2004;56:1221–1228

4. Rickard CM, Couchman BA, Hughes M, McGrail MR. Preventing hypothermia during continuous venovenous haemodiafiltration: a randomized controlled trial. J Adv Nurs. 2004;47:393–400.

Wednesday, July 25, 2018

Acetaminophen as a prophylaxis against PONV

Q: Acetaminophen (Tylenol/Paracetamol) can be used as a prophylaxis against post operative nausea vomiting (PONV)?

A) True
B) False


Answer: A

Meta-analysis published by Apfel Et al comprising of 2364 patients showed that if IV acetaminophen given prophylactically before arrival to recovery unit, it reduced the PONV in proportion with the reduction of pain (odds ratio 0.66, 0.47-0.93) (P=0.02) and vomiting (P=0.006).


#pharmacology 
#surgicalcriticalcare


Reference:

 Apfel CC, Turan A, Souza K, Pergolizzi J, Hornuss - Intravenous acetaminophen reduces postoperative nausea and vomiting: a systematic review and meta-analysis. Pain. 2013 May;154(5):677-89.

Tuesday, July 24, 2018

Phase 4 trial

Q: What is Phase 4 trial of any given drug?

Answer:  Relatively less publicised and less talked is the evaluation of a drug profile after it is approved and already in the market for patients. It looks over the time the efficiency and the side effects of a new drug/treatment. Usually, it is carried out over a longer period of time and look over thousands of patients.

#pharmacology


Reference:

Suvarna V. Phase IV of Drug Development. Perspectives in Clinical Research. 2010;1(2):57-60.

Monday, July 23, 2018

"Palm Method"

Q: How the "palm method" can be quickly used in estimating a Body Surface Area (TBSA) in patients? 


Answer: 

  • The palm of the patient's hand excluding the fingers is about 0.5 percent of total body surface area.
  • The palm of the patient's hand including the fingers is about 1 percent of total body surface area.
Above-said, although this is a quick method of TBSA but is not a very reliable one.


#burns



References:

1. Sheridan RL, Petras L, Basha G, et al. Planimetry study of the percent of body surface represented by the hand and palm: sizing irregular burns is more accurately done with the palm. J Burn Care Rehabil 1995; 16:605. 

2. Nagel TR, Schunk JE. Using the hand to estimate the surface area of a burn in children. Pediatr Emerg Care 1997; 13:254.

Sunday, July 22, 2018

Ambulation in DVT

Q: Patients with the diagnosis of acute deep venous thrombosis (DVT) should not be mobilized for 48 hours to avoid pulmonary embolism (PE)? 

A) True
B) False


Answer: B

Evidence does not support bed rest for patients with acute DVT. Early embolization does not convert DVT into PE. Though very aggressive physical therapy should not be pursued. Moreover, compression stockings may actually be helpful.


#cardiovascular
#pulmonary



References: 


1. Aschwanden M, Labs KH, Engel H, et al. Acute deep vein thrombosis: early mobilization does not increase the frequency of pulmonary embolism. Thromb Haemost 2001; 85:42. 


2. Anderson CM, Overend TJ, Godwin J, et al. Ambulation after deep vein thrombosis: a systematic review. Physiother Can 2009; 61:133. 


3. Aissaoui N, Martins E, Mouly S, et al. A meta-analysis of bed rest versus early ambulation in the management of pulmonary embolism, deep vein thrombosis, or both. Int J Cardiol 2009; 137:37. 


4. Partsch H, Blättler W. Compression and walking versus bed rest in the treatment of proximal deep venous thrombosis with low molecular weight heparin. J Vasc Surg 2000; 32:861.

Saturday, July 21, 2018

Cardioversion during pregnancy

Q; Cardioversion during pregnancy affects the rhythm of the fetus and fetus should be delivered prior to cardioversion?

A) True 
B) False


Answer:  B

Cardioversion can be performed safely during pregnancy and it does not affect fetus' rhythm, though it is recommended that the fetal heart rate is monitored.

#procedure
#cardiology
#procedures


References: 


1.vogel jh, pryor r, blount sg jr. direct-current defibrillation during pregnancy. jama 1965; 193:970.


2. Schroeder JS, Harrison DC. Repeated cardioversion during pregnancy. Treatment of refractory paroxysmal atrial tachycardia during 3 successive pregnancies. Am J Cardiol 1971; 27:445.

Friday, July 20, 2018

vagal responses

Q: Nasogastric tube placement (select one)

A)  increases the vagal tone
B) decreases the vagal tone


Answer: A

Various bedside maneuvers can cause increased vagal responses and may have undesired effects. It include prolonged sinus pauses or even asystole, atrioventricular blocks, or hemodynamic instability. Induction of  atrial fibrillation has been reported too. Carotid sinus massage may lead to stroke or transient ischemia attack (TIA).

Some common vagal maneuvers include carotid sinus massage, valsalva maneuver, eyeball pressure, breath holding, rectal exam, coughing, deep respirations, gagging, vomiting, swallowing, nasogastric (NG) tube placement and trendelenburg position.

#cardiology
#physicalexam



References:

1. Yamakawa K, So EL, Rajendran PS, et al. Electrophysiological effects of right and left vagal nerve stimulation on the ventricular myocardium. Am J Physiol Heart Circ Physiol 2014; 307:H722.

2. Davies AJ, Kenny RA. Frequency of neurologic complications following carotid sinus massage. Am J Cardiol 1998; 81:1256.

Thursday, July 19, 2018

On formula for the calculation of serum osmolality

Q; Why serum sodium is multiplied by 2 in the formula for the calculation of serum osmolality (Sosm)? 

 Calculated Sosm = (2 x serum [Na]) + [glucose]/18 + [BUN]/2.8 + [ethanol]/3.7 


 Answer: 

The serum sodium is multiplied by two in the formula to calculate serum osmolality is to account for accompanying anions (usually chloride and bicarbonate).

Moreover the divisors - 18, 2.8 and 3.7 - in the formula are to convert units of mg/dL to mosmol/kg 

When international units (mmol/L) are used, formula for 
Calculated Sosm = (2 x serum [Na]) + [glucose] + [urea] + (1.25 x [ethanol])


#electrolytes



References: 

1. Lynd LD, Richardson KJ, Purssell RA, et al. An evaluation of the osmole gap as a screening test for toxic alcohol poisoning. BMC Emerg Med 2008; 8:5. 

2. Purssell RA, Pudek M, Brubacher J, Abu-Laban RB. Derivation and validation of a formula to calculate the contribution of ethanol to the osmolal gap. Ann Emerg Med 2001; 38:653.

Wednesday, July 18, 2018

Diuretic dose in CHF exacerbation

Q: 62 year old male with history of congestive heart failure (CHF) and previously stable on home medications  presented with acute exacerbation of CHF requiring Non Invasive Positive Pressure Ventilation (NIPPV). The recommended required dose of diuretic for this patient?

A) As equal as home dose
B) About 2.5 times of home dose
C) Start with lowest dose 
D) furosemide drip with 10 mg/hr
E) Add metolazone to home diuretic dose


Answer: B

Patients with acute exacerbation of CHF who are chronically on diuretics at home usually requires about 2.5 times of their baseline total daily dose. This came from the DOSE trial which showed benefit towards improved clinical symptoms in patients in higher dose arm of the study.

Continuous IV infusion can be initiated but requires IV bolus dose prior to it (choice D).

Metolazone is usually added as a second step when response to diuretic is not desirable (choice E).

#cardiology
#pharmacology


Reference:

Felker GM, Lee KL, Bull DA, et al. Diuretic strategies in patients with acute decompensated heart failure. N Engl J Med 2011; 364:797.

Tuesday, July 17, 2018

transvalvular left ventricular assist device

Q: Which of the following is percutaneous transvalvular left ventricular assist device?

A) Percutaneous left atrial-to-femoral arterial ventricular assist device (Tandem Heart ©)
B) Fem-Fem Extracorporeal membrane oxygenator (ECMO)
C) Percutaneous left ventricular assist device (Impella ©)
D) Intra-aortic Balloon Pump (IABP)
E) Pulmonary artery catheter (Swan-Ganz or PAC)


Answer: C

Tandem Heart © is placed via the femoral vein and across the interatrial septum to provide circulatory support. (choice A)

Bilateral femoral cannulas for ECMO do not cross any heart valve. (choice B)

Impella © is placed retrograde via the femoral artery, crosses the aortic valve into the left ventricle, unload the ventricle into the aorta. (choice C)

IABP never reaches the heart. (choice D)

PAC is a diagnostic tool, not a therapeutic tool or an assisted device. (choice E)

#cardiology
#procedures


References:

Lauten A, Engström AE, Jung C, et al. Percutaneous left-ventricular support with the Impella-2.5-assist device in acute cardiogenic shock: results of the Impella-EUROSHOCK-registry. Circ Heart Fail 2013; 6:23.

Monday, July 16, 2018

Ultrasound of lungs - review

Q: What does "shred sign" signifies on lung ultrasound?

Answer:  Many times consolidations in lung may get missed via regular chest X-ray particularly only on supine films in ICUs. Ultrasound has an advantage to pick those hidden consolidations. It can be picked by the irregular, shaggy border between the consolidated and normally aerated lung and is known as “shred sign”.

Beautiful pictorial review on ultrasound of lungs here

Link: https://goo.gl/9WEL3j


Reference: Chichra A, Makaryus M, Chaudhri P, Narasimhan M. Ultrasound for the Pulmonary Consultant. Clinical Medicine Insights Circulatory, Respiratory and Pulmonary Medicine. 2016;10:1-9.

Sunday, July 15, 2018

Peritoneal Dialysis Catheter ESIs

Q: 27 year old male on kidney transplant list and now on peritoneal dialysis is admitted for sepsis and hypotension after his weekend trip to the water park. The probable source of sepsis appears to be a peritoneal dialysis catheter exit site. Surgical service is consulted in addition to initiation of antibiotics and continuous renal replacement therapy (CRRT). All of the following are considered as preventive measures to decrease exit site infections (ESIs) except?

A) Daily topical antibiotic at the exit site
B) Daily topical nasal antibiotics
C) Cover the exit site with an ostomy bag while swimming
D) Discourage pets at house
E) Regular cleaning of the exit site with chlorhexidine solution



Answer: B

The objective of the above question is to emphasize that regular application of nasal antibiotics do not decrease the infection rate in patients with chronic catheter insertion.  Also, another objective of the above MCQ is to highlight the risk of zoonotic infections as a probable cause of sepsis in such patients (choice D).

#surgicalcriticalcare
#nephrology
#infectiousdiseases


References:

1. Szeto CC, Li PK, Johnson DW, et al. ISPD Catheter-Related Infection Recommendations: 2017 Update. Perit Dial Int 2017; 37:141.

2.  Broughton A, Verger C, Goffin E. Pets-related peritonitis in peritoneal dialysis: companion animals or trojan horses? Semin Dial 2010; 23:306.

Saturday, July 14, 2018

Fluorescence bronchoscopy

Q: What is Fluorescence bronchoscopy?

Answer:  Fluorescence bronchoscopy can detect pre-invasive lesions such as squamous cell carcinoma which develops a fluorescent property. When combined with the regular bronchoscopy it increases the detection of airway preinvasive lesions, particularly high grade, and biopsies can be taken at the same time. Though technology is still in its nascent stages and has not been studied well it is a hope that by detecting lesions earlier it will reduce the morbidity and mortality of lung cancers.

#pulmonology
#procedures




References/further reads:

1. Kurie JM, Lee JS, Morice RC, et al. Autofluorescence bronchoscopy in the detection of squamous metaplasia and dysplasia in current and former smokers. J Natl Cancer Inst 1998; 90:991. 1


2. Edell E, Lam S, Pass H, et al. Detection and localization of intraepithelial neoplasia and invasive carcinoma using fluorescence-reflectance bronchoscopy: an international, multicenter clinical trial. J Thorac Oncol 2009; 4:49.

3. Banerjee AK, Rabbitts PH, George J. Lung cancer. 3: Fluorescence bronchoscopy: clinical dilemmas and research opportunities. Thorax 2003; 58:266.

4. Ikeda N, Honda H, Hayashi A, et al. Early detection of bronchial lesions using newly developed videoendoscopy-based autofluorescence bronchoscopy. Lung Cancer 2006; 52:21.

5.Chiyo M, Shibuya K, Hoshino H, et al. Effective detection of bronchial preinvasive lesions by a new autofluorescence imaging bronchovideoscope system. Lung Cancer 2005; 48:307.

6. Loewen G, Natarajan N, Tan D, et al. Autofluorescence bronchoscopy for lung cancer surveillance based on risk assessment. Thorax 2007; 62:335.

Friday, July 13, 2018

pulmonary function score ratio (PFS ratio) in Guillain-Barré syndrome

Q: How pulmonary function score ratio (PFS ratio) helps in patients with Guillain-Barré syndrome?


Answer: Calculating pulmonary function score ratio (PFS ratio) in patients with Guillain-Barré syndrome may guide into the time of tracheostomy as it predicts the length of intubation.

PFS = VC (in mL/kg) + MIP (in cm H2O) + MEP (in cm H2O)

VC = vital capacity
MIP =  maximal inspiratory pressure 
MEP = maximal expiratory pressure. 

The PFS ratio: is obtained by dividing PFS immediately prior to intubation and PFS on the 12th day of mechanical ventilation. 

A PFS ratio < 1  predicts the need for mechanical ventilation for more than 3 weeks with the specificity of 100 percent.

#pulmonary



Reference:

Lawn ND, Wijdicks EF. Post-intubation pulmonary function test in Guillain-Barré syndrome. Muscle Nerve 2000; 23:613.

Thursday, July 12, 2018

ARDS and aerosol delivery

Q: All of the following are the effects of prone positioning in Acute Respiratory Distress Syndrome (ARDS) except? 

A)  Improved configuration between lung and thorax 
B) Less abdominal pressure 
C) Improved secretion mobilization 
D) Decreased aerosol delivery
E) More homogeneous perfusion 


Answer: D

Although prone positioning is around for a while it tool few decades to understand the physiologic effects and a proper way to operate it. Recently, this results in evidence-based literature leaning towards its application in severe ARDS particularly prior to application of extracorporeal membrane oxygenation (ECMO). All of the above are the effects of prone position except D as prone position increase/improve the aerosol delivery due to reopening of the more alveoli.


Reference:


Oczenski W, Hörmann C, Keller C, et al. Recruitment maneuvers during prone positioning in patients with acute respiratory distress syndrome. Crit Care Med 2005; 33:54.

Wednesday, July 11, 2018

hypertriglyceridemia and pseudohyponatremia.

Q: Severe hypertriglyceridemia may cause pseudohyponatremia. What is the usual correlation? 

Answer: On average, an 886 mg/dL increase in plasma triglycerides reduces the serum sodium concentration by approximately 1 mEq/L.

#electrolytes



Reference:


Dimeski G, Mollee P, Carter A. Effects of hyperlipidemia on plasma sodium, potassium, and chloride measurements by an indirect ion-selective electrode measuring system. Clin Chem 2006; 52:155.

Tuesday, July 10, 2018

QT Interval measurement preferred lead

Q: Which leads in EKG are preferred to measure the QT interval?


Answer: Leads II and V5 

Lead II and lead V5 is preferred due to the fact that termination of T waves is most clearly visible in these leads, which makes these leads best to measure reliable QT interval.

#cardiology



Reference:

Cowan JC, Yusoff K, Moore M, et al. Importance of lead selection in QT interval measurement. Am J Cardiol 1988; 61:83.

Monday, July 9, 2018

Antimicrobial bladder irrigation

Q: Urinary bladder irrigation is a common procedure used in ICUs. Antimicrobial irrigation has been proposed. Evidence based literature shows that antimicrobial irrigation of the bladder (select one)

A) prevent the urinary tract infections
B) Delay the urinary tract infections
C) Increases the risk for urinary tract infections
D) No effect on urinary tract infections


Answer: C

Antimicrobial irrigation of the bladder does not prevent or delay the urinary tract infections (UTIs), rather studies have shown that it may increase the risk for UTIs. Also, it may subject patients to develop more resistance to the organisms. Irrigation with sterile saline is perfectly acceptable.


#urology
#infectiousdiseases
#procedures
#surgicalcriticalcare


Reference:

1. Warren JW, Platt R, Thomas RJ, et al. Antibiotic irrigation and catheter-associated urinary-tract infections. N Engl J Med 1978; 299:570. 


Sunday, July 8, 2018

Bicarb and ECF volume

Q: A 50 mL ampule of 50 mEq of sodium bicarbonate (popularly known as "1 amp of bicarb") expands the Extra Cellular Fluid (ECF) volume by approximately 

A) 50 mL 
B) 100 mL
C) 250 mL.
D) 500 mL
E) unpredictable


Answer: C

"one amp of bicarb" expands the ECF volume by approximately 250 mL, which is approximately equivalent to one IVF bolus!

#acidbase


Reference: 

Alpern RJ, Cogan MG, Rector FC. Effects of extracellular fluid volume and plasma bicarbonate concentration on proximal acidification in the rat. Journal of Clinical Investigation. 1983;71(3):736-746.

Saturday, July 7, 2018

PEEP in venous air embolism

Q: During the management of venous air embolism (VAE), with an intubated patient, positive end-expiratory pressure (PEEP) should be (select one)

A) increased
B) optimized by running pressure-volume (PV) loop on ventilator
C) discontinued
D) May keep PEEP at 5 cm H2O
E) C and D


Answer: E

Increasing the PEEP increases the chance of an intracardiac right-to-left shunt, which may convert a VAE into a paradoxical air embolism (PAE), a life-threatening complication (choice A). During VAE there is no luxury of time to run PV loop (choice B).

There is a lot of debate between choices C and D but evidence is very weak to recommend to discontinue the PEEP (choice C) though it can be done if danger of hypoxemia is not anticipated. Ans, some studies have suggested a benefit of (regular) PEEP in prevention of VAE.

Objective of the above question is to highlight the controversy of PEEP in the management of VAE


#ventilators
#cardiology


References:

1. Meyer, PG Cuttaree, H Charron, B Jarreau, MM Peri, AC Sainte-Rose, C Perkins NA, Bedford RF: Hemodynamic consequences of PEEP in seated neurological patients: Implications for paradoxical air embolism. Anesth Analg 1984; 63:429–32

2. Perkins, NA Bedford, RF Zasslow MA, Pearl RG, Larson CP, Silverberg G, Shuer LF: PEEP does not affect left atrial-right atrial pressure difference in neurosurgical patients. Anesthesiology 1988; 68:760–3

3. Zasslow, MA Pearl, RG Larson, CP Silverberg, G Shuer, LF Schmitt HJ, Hemmerling TM: Venous air emboli occur during release of positive end-expiratory pressure and repositioning after sitting position surgery. Anesth Analg 2002; 94:400–3

4. Schmitt, HJ Hemmerling, TM Giebler R, Scherer R, Erhard J: Effect of positive end-expiratory pressure on the incidence of venous air embolism and on the cardiovascular response to the sitting position during neurosurgery. Br J Anaesth 1998; 80:30–5Giebler, R Scherer, R Erhard, J

Friday, July 6, 2018

response of benzodiazepine in convulsive status epilepticus

Q: How long one should wait to see the response of  benzodiazepine in patients with convulsive status epilepticus before administrating the repeat dose?


Answer:  one minute

First line of treatment in patients with convulsive status epilepticus is lorazepam with either the calculated dose of 0.1 mg/kg IV (2 mg/min) or a 4 mg fixed dose. It takes about one minute to see the full response of lorazepam as it is a lipophilic drug. If intravenous access is not available In the pre-hospital 10 mg of intramuscular (IM) midazolam can be given as an alternative.

#neurology
#pharmacology


Reference: 

Brophy GM, Bell R, Claassen J, et al. Guidelines for the evaluation and management of status epilepticus. Neurocrit Care 2012; 17:3.

Thursday, July 5, 2018

Lund-Browder chart

Q: Lund-Browder chart is the most accurate way of estimating Total Body Surface Area (TBSA) in:

A) Burn
B) Pressure ulcer
C) Insensible loss
D) Vasculopathy
E) Calculation of Cardiac Index (CI)


Answer: A 


Though "Rule of Nines" is the most well known and most widely used method to estimate TBSA in burn patients, the Lund-Browder chart, developed almost 75 years ago, is still the most accurate method for estimating TBSA. It has a particular advantage of being applicable in adults, children as well as infants. Charts are available online with any search engine. Click on the link


https://goo.gl/so5eaC

#burn
#pediatrics 


Reference:

Lund CC, Browder NC. The estimation of areas of burns. Surg Gynecol Obstet 1944; 79:352.

Tuesday, July 3, 2018

Motor Activity Assessment Score (MAAS)

Q: Motor Activity Assessment Score (MAAS) is a

A) Post stroke score

B) Sedation score
C) ICU myopathy score
D) Early mobilization score
D) Electromyography (EMG) score


Answer: B

Motor Activity Assessment Score (MAAS) runs from 0 to 6 where 0 is unresponsive and 6 is dangerously  agitated.

ovidweb.jpeg

Reference:

Devlin, John W. et al. “Motor Activity Assessment Scale”. Critical Care Medicine 27.7 (1999): 1271-1275.

Monday, July 2, 2018

jugular venous oxygen saturation (SjVO2)

Q: Normal jugular venous oxygen saturation (SjVO2) in patients with Traumatic Brain Injury (TBI) is considered to be approximately at 

A) 80%
B) 70%
C) 60%
D 50%
E) 40%


Answer: C

Jugular venous oximetry is an advanced neuromonitoring technique in TBI patients and it can be obtained with retrograde cannulation of the internal jugular vein. It reflects well with the measurement of oxygen saturation in the blood exiting the brain. Normal  SjVO2 is considered to be approximately at 60 percent. SjVO2 less than 50 percent for mere 10 minutes is considered as an "ischemic desaturation", impaired cerebral perfusion pressure (CPP) and poor outcome.

#Trauma
#neurosurgery


References:

1. Cruz J. The first decade of continuous monitoring of jugular bulb oxyhemoglobinsaturation: management strategies and clinical outcome. Crit Care Med 1998; 26:344. 

2. Brain Trauma Foundation, American Association of Neurological Surgeons, Congress of Neurological Surgeons, et al. Guidelines for the management of severe traumatic brain injury. X. Brain oxygen monitoring and thresholds. J Neurotrauma 2007; 24 Suppl 1:S65.

Sunday, July 1, 2018

Spiked Helmet sign

Q: 'Spiked Helmet' on EKG is due to

A) Hypothermia
B) Acute myocardial infarction (MI)
C) Hypokalemia
D) Repetitive contraction of the diaphragm 
E) prolong QT interval


Answer: D

"The spiked helmet sign is a potential novel ECG marker of a very high risk of impending death, but the prevalence, mechanism, and clinical applicability remain uncertain at this time".

Above statement is referenced from the following article:

"The “Spiked Helmet” Sign: A New Electrocardiographic Marker of Critical Illness and High Risk of Death" 


Citation: Littmann L, Monroe MH. The “Spiked Helmet” Sign: A New Electrocardiographic Marker of Critical Illness and High Risk of Death. Mayo Clinic Proceedings. 2011;86(12):1245-1246. doi:10.4065/mcp.2011.0647

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3228627/


#cardiology