Body heat regulation

Q: All of the following body organs are involved in heat regulation of the body except? 

A) heart 
B) liver
C) skin 
D) lungs
E) kidney


Answer: E

During winter season, accidental hypothermia is very common. Beside clinical management of hypothermia, it is important to understand the basic pathophysiology of accidental hypothermia. Body temperature regulation is a balance between heat production and heat loss. Heat is produced by cellular metabolism mostly from the heart and liver. Heat is lost from the body mostly via skin and the lungs. Four methods of heat loss are evaporation, radiation, conduction, and convection. Decrease surrounding temperature increases heat loss. With temperature in the surrounding start to decrease, the hypothalamus stimulates the heat production through shivering and increased thyroid, catecholamine, and adrenal activity. Also, vasoconstriction occurs via 2 methods.

• Sympathetically mediated vasoconstriction, and 
• Peripheral vasoconstriction as a direct response 

All these compensatory mechanisms start to wane as core body temperature reaches  35°C. And once the core body temperature reaches 32°C, metabolism, ventilation, cardiac output, and shivering compensatory mechanisms are lost.

#hypothermia


References:

1. Hanania NA, Zimmerman JL. Accidental hypothermia. Crit Care Clin 1999; 15:235. 
2.Jolly BT, Ghezzi KT. Accidental hypothermia. Emerg Med Clin North Am 1992; 10:311. 
3. Lee-Chiong TL Jr, Stitt JT. Disorders of temperature regulation. Compr Ther 1995; 21:697.

Pitfall of Amylase in Acute Pancreatitis

Q: Markedly elevated triglyceride level in acute pancreatitis can falsely (select one)

 A) Increase the amylase level in laboratory
 B) normalize the amylase level in laboratory


 Answer: B

Once serum triglyceride levels go above 500 mg/dL, it may falsely normalize the amylase level. This is due to an interference of the calorimetric reading. In such scenarios, the lipase level would be more reliable as an indicator of the severity of acute pancreatitis.

#gastroenetrology
 #laboratory-medicine



References:

 1. Howard JM, Reed J. Pseudohyponatremia in acute hyperlipemic pancreatitis. A potential pitfall in therapy. Arch Surg 1985; 120:1053.

 2. Fallat RW, Vester JW, Glueck CJ. Suppression of amylase activity by hypertriglyceridemia. JAMA 1973; 225:1331.

gunshot wound to the flank and back

Q: Patients with a gunshot wound (GSW) to the flank and back should get?

A) Diagnostic peritoneal lavage (DPL)
B) Bedside ultrasound (US)
C) Diagnostic laparoscopy
D) CT scan of the abdomen and Pelvis with IV, oral, and rectal contrast
E) CT scan of the abdomen and Pelvis, only with oral contrast, saving the kidney


Answer: D

Patients with a gunshot wound (GSW) to the flank and back should be evaluated with a different approach. Due to the location of the injury DPL, the US or diagnostic laparoscopy may not provide adequate or may even mislead the extent of the injury. The best tool would be a CT scan of the abdomen and the pelvis with IV, oral, and rectal contrast. This will reliably delineate the path of the missile and extent of the injury. 

As far as a patient is having good urine output and Creatinine is normal, IV contrast can be given safely (choice E)

#trauma


References: 

1. Albrecht RM, Vigil A, Schermer CR, et al. Stab wounds to the back/flank in hemodynamically stable patients: evaluation using triple-contrast computed tomography. Am Surg 1999; 65:683.

2. Ginzburg E, Carrillo EH, Kopelman T, et al. The role of computed tomography in selective management of gunshot wounds to the abdomen and flank. J Trauma 1998; 45:1005.

Drug-Eluting Stents and Coronary Artery Aneurysm

Q: The mean time period between the deployment of Drug-Eluting Stents (DES) and development of Coronary Artery Aneurysm (CAA) is

A) one week
B) one month
C) three months
D) six months
E) one year


Answer: E

Development of CAA after the deployment of DES is relatively an insidious process. Reported mean time to have its clinical effect is around 313 days. As expected, risk factors include DES deployment during an acute myocardial infarction (MI), deployment in an occluded vessel, longer coronary lesions requiring multiple overlapping stents, residual dissection, and underlying congenital and Kawasaki's disease-related aneurysms.

#cardiology
#procedures



References:

1. Alfonso F, Pérez-Vizcayno MJ, Ruiz M, et al. Coronary aneurysms after drug-eluting stent implantation: clinical, angiographic, and intravascular ultrasound findings. J Am Coll Cardiol 2009; 53:2053. 

2. Aoki J, Kirtane A, Leon MB, Dangas G. Coronary artery aneurysms after drug-eluting stent implantation. JACC Cardiovasc Interv 2008; 1:14. 

Off label use of cardiac devices

Q: Device which is used to close atrial septal defect (ASD) or patent foramen ovale (PFO) known as Amplatzer device - can also be used (off label) to close

A) Brochopleural Fistula (BPF)
B) Aortic Valve Stenosis 
B) Esophageal perforation
D) Atrio-Venous malformations
E) Aorto-enteric fistula


Answer: A

Amplatzer device is intended for use to close the atrial septal defect or patent foramen ovale. It is particularly useful when BPFs are of larger size and can't be closed by a sealant.

#interventional-pulmonary



References:

1. Gómez López A, García Luján R, De Pablo Gafas A, et al. First use of Amplatzer device for bronchopleural fistula after lung transplantation. Thorax 2017; 72:668. 

2. Fruchter O, El Raouf BA, Abdel-Rahman N, et al. Efficacy of bronchoscopic closure of a bronchopleural fistula with amplatzer devices: long-term follow-up. Respiration 2014; 87:227.

occult cardiogenic shock

Q: One of the deceiving forms of acute congestive heart failure is "occult shock", where it may be difficult to distinguish end-stage CHF patients from mildly decompensated CHF patients. Which one lab test may be vital and ideally should be obtained in all patients with acute decompensated CHF?


Answer: Lactic acid

One of the deceiving forms of acute congestive heart failure is "occult shock", where it may be difficult to distinguish end-stage CHF patients from mildly decompensated CHF patients. High lactate level indicates acute emergency in such patients and may require relatively early initiation of inotrope, floatation of pulmonary artery catheter (PAC) to guide the volume management and managing perfusion to other vital organs.

#cardiology


Reference:

Ander DS, Jaggi M, Rivers E, et al. Undetected cardiogenic shock in patients with congestive heart failure presenting to the emergency department. Am J Cardiol 1998; 82:888.

Lidocaine toxicity

Q: Which of the following can be an earliest sign of  intravenous (IV) lidocaine infusion toxicity? 

 A) Tremor 
 B) Sinus slowing 
C) Hypotension 
D) Increase in the threshold of an implantable cardioverter-defibrillator (AICD) 
E) Nausea and vomiting


Answer:  A

Objective of the above question is to emphasize that lidocaine's earliest signs of toxicity is central nervous system (CNS) based instead of cardio-vascular (CVS) based. They are mostly age and dose-dependent, and at the level of liver insufficiency. Interestingly, and often ignored earliest sign of lidocaine toxicity is tremor. Also sleep disturbance, lightheadedness, slurred speech, delirium and in worse cases seizure may occur.

 CVS side-effects may occur but less likely than CNS side-effects. Lidocaine has shown to increase the defibrillation threshold of AICDs, but this effect may not be significant at clinical level.

 Gastrointestinal (GI) toxicities are not different from any other medications.

#neurology
#pharmacology
#cardiology
#toxicology


References:

Rademaker AW, Kellen J, Tam YK, Wyse DG. Character of adverse effects of prophylactic lidocaine in the coronary care unit. Clin Pharmacol Ther 1986; 40:71. 

Lown B, Vassaux C. Lidocaine in acute myocardial infarction. Am Heart J 1968; 76:586. 

Pfeifer HJ, Greenblatt DJ, Koch-Weser J. Clinical use and toxicity of intravenous lidocaine. A report from the Boston Collaborative Drug Surveillance Program. Am Heart J 1976; 92:168. 

Schumacher RR, Lieberson AD, Childress RH, Williams JF Jr. Hemodynamic effects of lidocaine in patients with heart disease. Circulation 1968; 37:965. 

Dorian P, Fain ES, Davy JM, Winkle RA. Lidocaine causes a reversible, concentration-dependent increase in defibrillation energy requirements. J Am Coll Cardiol 1986; 8:327.

Pelvic Fracture

Case: 72 year old nursing home resident in ICU is recovering from pneumonia. The patient fell down while participating in physical therapy at the bedside. There are some bruises noted at inner thigh near the scrotal area. You were informed that it will take a while to obtain a CT scan due to logistic issues. As a first step how the X-ray of the pelvis should be ordered?


Answer: Unfortunately, the utility of simple X-ray in a pelvic fracture is limited. The sensitivity to obtain any pathology can be increased by ordering X-ray with specific instructions to -

 "project beam 40 degrees caudad for inlet views and 40 degrees cephalad for outlet views".

#trauma 


References: 

1. Kirby MW, Spritzer C. Radiographic detection of hip and pelvic fractures in the emergency department. AJR Am J Roentgenol 2010; 194:1054. 

2. Dominguez S, Liu P, Roberts C, et al. Prevalence of traumatic hip and pelvic fractures in patients with suspected hip fracture and negative initial standard radiographs--a study of emergency department patients. Acad Emerg Med 2005; 12:366.

Calcium channel blockers and dialysis

Q: Calcium channel blockers (CCBs) get removed by hemodialysis (HD)? (select one)

A) Yes
B) No


Answer: B

As CCBs are highly protein bound, they can not be removed by hemodialysis.

This small piece of information is very vital in toxicology to learn that  HD has no role in CCBs overdose.


#toxicology
#pharmacology
#nephrology



Reference: 

Sica DA, Gehr TW. Calcium-channel blockers and end-stage renal disease: pharmacokinetic and pharmacodynamic considerations. Curr Opin Nephrol Hypertens. 2003 Mar;12(2):123-31.

pickering syndrome

Q: Pickering Syndrome is described as a combination of “flash” pulmonary edema and? (select one)

A) unilateral renal artery stenosis
B) bilateral renal artery stenosis


Answer: B

Pickering was the first to describe the association between acute (flash) pulmonary edema and renal artery stenosis. He reported that acute pulmonary edema in renal artery stenosis patients predicts more of bilateral pathology instead of unilateral. Treatment is renal artery stents placement.

#nephrology
#cardiology


References:

Pickering TG, Herman L, Devereux RB, et al. Recurrent pulmonary oedema in hypertension due to bilateral renal artery stenosis: treatment by angioplasty or surgical revascularisation. Lancet 1988; 2:551.

Bloch MJ, Trost DW, Pickering TG, et al. Prevention of recurrent pulmonary edema in patients with bilateral renovascular disease through renal artery stent placement. Am J Hypertens 1999; 12:1. 


Pelta A, Andersen UB, Just S, Bækgaard N. Flash pulmonary edema in patients with renal artery stenosis--the Pickering Syndrome. Blood Press 2011; 20:15.

Acute Mx of Adrenal Crisis

Q: All of the following are part of the immediate (acute) management of adrenal crisis except?

A) Immediate glucose check
B) Infusion of 5% dextrose in isotonic saline
C) 4 mg dexamethasone (decadron) 
D) 0.1 mg fludrocortisone
E) large-bore intravenous access


Answer: D

All of the above are required immediately to avoid the hemodynamic collapse of a patient with adrenal crisis except fludrocortisone. Mineralocorticoid replacement (fludrocortisone) takes several days to induce its sodium-retaining effects, and in immediate phase sodium replacement should be done via IV normal saline. D-5 is added to IV saline to treat hypoglycemia of adrenal crisis.

Also, out of primary, secondary and tertiary adrenal inefficiencies, only primary adrenal insufficiency is associated with both cortisol and mineralocorticoid deficiency.

#endocrinology


References: 

1. Hahner S, Allolio B. Therapeutic management of adrenal insufficiency. Best Pract Res Clin Endocrinol Metab. 2009 Apr. 23(2):167-79. 

2. Arlt W, Society for Endocrinology Clinical Committee. SOCIETY FOR ENDOCRINOLOGY ENDOCRINE EMERGENCY GUIDANCE: Emergency management of acute adrenal insufficiency (adrenal crisis) in adult patients. Endocr Connect. 2016 Sep. 5 (5):G1-G3

EKG in prone position

Q: In patients who are placed in prone position, electrocardiographic (EKG) leads can be placed on the back?

A) True
B) False


Answer:  A

Not only EKG leads can be safely placed and interpreted from the back of the patient but successful defibrillation can also be done.

It would be appropriate to notify the reading cardiologist if leads are placed on the back.

#cardiology
#procedure



References:

Russi CS, Myers LA, Kolb LJ, Steever K, Nestler DM, Bjerke MC, White RD, Ting HH. - Prehospital diagnosis of ST-segment elevation myocardial infarction using an "all-posterior" 12-lead electrocardiogram.- prehosp Emerg Care. 2011 Jul-Sep;15(3):410-3. 

C. C. Miranda, M. C. Newton; Successful defibrillation in the prone position, BJA: British Journal of Anaesthesia, Volume 87, Issue 6, 1 December 2001, Pages 937–938

SAVE Score

Q: SAVE score is the prediction of survival in patients after Extracorporeal membrane oxygenation (ECMO) in adults for respiratory failure? 

A) True 
B) False


Answer:  B

The objective of the above question is to highlight two standard scores in ECMO patients.

1. RESP score, and
2. SAVE score

These two Scores have been developed by The Extracorporeal Life Support Organization (ELSO) and The Department of Intensive Care at The Alfred Hospital, Melbourne. They are designed to assist prediction of survival for adult patients undergoing ECMO.

RESP score consists of 12 variables and predicts ECMO survival in respiratory failure.
SAVE Score consists of 11 variables and predicts ECMO survival in cardiogenic shock.

They can be accessed at: http://www.save-score.com and http://www.respscore.com

#ECMO
#cardiology
#pulmonary


References:

1. Schmidt M et al; Am J Respir Crit Care Med 2013; 189: 1374 - 1382. 

2. Schmidt M et al; Eur Heart J. 2015 Sep 1;36(33):2246-56

3. 1. Chen WC, Huang KY, Yao CW, et al. The modified SAVE score: predicting survival using urgent veno-arterial extracorporeal membrane oxygenation within 24 hours of arrival at the emergency department. Crit Care. 2016;20(1):336. Published 2016 Oct 22.

Treatment of methemoglobinemia

Q: Which of the following vitamins can be used in the treatment of methemoglobinemia (MHb) if Methylene Blue (MB) cannot be used  or not available for any reason?

A) Vitamin A
B) Vitamin B-12
C) Vitamin C
D) Vitamin D 
E) Folic acid (vitamin B-9)


Answer: 

Ascorbic acid (vitamin C) has a reducing potential and can be safely and effectively used at a dose of 1 to 10 grams IV every six hours till recovery from (MHb). Use of even higher doses has been described in the literature.

#toxicology



References:

1. Park SY, Lee KW, Kang TS. High-dose vitamin C management in dapsone-induced methemoglobinemia. Am J Emerg Med 2014; 32:684.e1. 

2. Rehman A, Shehadeh M, Khirfan D, Jones A. Severe acute haemolytic anaemia associated with severe methaemoglobinaemia in a G6PD-deficient man. BMJ Case Rep 2018; 2018. 

3. Rees DC, Kelsey H, Richards JD. Acute haemolysis induced by high dose ascorbic acid in glucose-6-phosphate dehydrogenase deficiency. BMJ 1993; 306:841.

PO Diflucan

Q: Care should be taken while converting intravenous (IV) fluconazole to oral (PO) route as it's bio-availability is extremely variable? 

A) True 
B) False 


 Answer: B 

Fluconazole is highly bio-available and IV form should be used only when a patient is unable to take oral medications, or for some reason poor gastrointestinal absorption is suspected.

Objective of above question is to understand the overuse and high cost of IV formulations in ICU. 

#pharmacology
#infectiousdiseases



Reference:

Diflucan - fda.gov 
https://www.accessdata.fda.gov/drugsatfda_docs/label/2011/019949s051lbl.pdf

IV Haldol

Q: Intravenous (IV) administration of haloperidol may have a higher risk of extrapyramidal side effects than oral administration? (select one) 

A) True 
B) False


Answer:  B

Although IV Haloperidol has a high-grade warning from FDA, it is very commonly used at the bedside. Interestingly, IV Haloperidol tends to cause lower extrapyramidal side effects than oral administration. 

Not fully explained but this is probably due to avoidance of first-pass metabolism, saving brain from the effects of metabolites.

#psychiatry
#pharmacology
#neurology


Reference:

 Menza MA, Murray GB, Holmes VF, Rafuls WA: Decreased extrapyramidal symptoms with intravenous haloperidol. J Clin Psychiatry 1987; 48:278–280

Oxygen in acute CHF

Q: What is the pitfall of administrating excess oxygen to patients with acute decompensation of congestive heart failure (CHF)?



Answer: Although oxygen should be administrated to counter hypoxemia in patients with acute exacerbation of CHF, the excess of it may cause vasoconstriction and may cause counter-productive decrease in cardiac output. This again reinforce to treat oxygen as a drug.

#cardiology
#pharmacology



Reference:

Park JH, Balmain S, Berry C, et al. Potentially detrimental cardiovascular effects of oxygen in patients with chronic left ventricular systolic dysfunction. Heart 2010; 96:533.

Hyponatremia in hepatic cirrhosis

Q: Hyponatremia should be treated aggressively in hepatic cirrhosis patients who are not the candidates for liver transplant? (select one)

A) True
B) False


Answer: B

In contrast to hypokalemia, hyponatremia practically has no clinical effect on patients with liver cirrhosis unless until it is less than 120 mEq/L. 

It requires treatment only in 2 cases

1. If neurologic symptoms appear to be related to hyponatremia

2. A patient is going for a liver transplant. In such a case, sodium should be raised to 130 mEQ/L. Again, care should be taken to avoid very rapid correction due to the risk of osmotic demyelination syndrome (central pontine myelinolysis).

#hepatology
#electrolytes


References:

Angeli P, Wong F, Watson H, et al. Hyponatremia in cirrhosis: Results of a patient population survey. Hepatology 2006; 44:1535.

measuring CSF pressure

Q: During lumbar puncture (LP) the accurate cerebro-spinal fluid (CSF) pressure is measured with a manometer in a patient lying flat in the lateral decubitus position with the legs? (select one) 

 A) extended 
 B) flexed


Answer: A

Although controversy persists about the clinical significance but flexing the legs during the LP may falsely elevate the CSF pressure. An LP can be performed with the patient in the prone, lateral recumbent or sitting upright. The lateral recumbent or prone positions provides the most accurate measurement of the opening pressure. In lateral recumbent position, initially patient remains in the fetal position with the neck, back, and limbs held in flexion. 

Once CSF begins to flow, the patient should be asked to slowly extend the legs. This allows the free flow of CSF within the subarachnoid space. A manometer then is placed over the hub of the needle and the opening pressure is measured.

Please refer to manuals for detailed proper positioning and technique.

#procedures
#neurology



References:

1. Rajagopal V, Lumsden DE. Best BETs from the Manchester Royal Infirmary. BET 4: does leg position alter cerebrospinal fluid opening pressure during lumbar puncture? Emerg Med J 2013; 30:771. 

2.Abel AS, Brace JR, McKinney AM, et al. Effect of patient positioning on cerebrospinal fluid opening pressure. J Neuroophthalmol 2014; 34:218.

B-Blocker after Thyroid storm

Q: Beta-Blocker (BB) should be discontinued as soon as thyroid storm is clinically improved? (select one)

A) True
B) False


Answer: B

Although BB is used to control the acute symptoms of thyroid storm, it should be discontinued only after the thyroid function tests (TFTs) have returned to normal. This is due to the fact that BB, particularly Propranolol may continue to help in reducing the serum T3 levels.

#endocrine
#pharmacology 



References:

Cooper DS, Daniels GH, Ladenson PW, Ridgway EC. Hyperthyroxinemia in patients treated with high-dose propranolol. Am J Med 1982; 73:867.

Cough in extubation

Q: Despite passing weaning parameters, poor cough strength is a reliable indicator of failed extubation. What is an easy bedside method to test adequate cough strength in a patient who otherwise seems ready for extubation? 



Answer: After detaching endotracheal tube (ETT) from the ventilator circuit, an index card is held about 2 cm from the end of the ETT. A patient who is unable to moisten the card with few efforts of cough is more likely to fail extubation. 1

Extubation failure is well documented in patients who cannot cough on demand despite good weaning parameters. More appropriate method to test the cough strength is to insert a spirometer into the ventilator circuit. Strength of cough can be measured with peak expiratory flow (PEF) during the cough. PEF ≤60 L/min are five times more likely to fail extubation.


#ventilators
#pulmonary


References/further reading:

1. Khamiees M, Raju P, DeGirolamo A, et al. Predictors of extubation outcome in patients who have successfully completed a spontaneous breathing trial. Chest 2001; 120:1262. 

2. Beuret P, Roux C, Auclair A, et al. Interest of an objective evaluation of cough during weaning from mechanical ventilation. Intensive Care Med 2009; 35:1090. 

3. Thille AW, Boissier F, Ben Ghezala H, et al. Risk factors for and prediction by caregivers of extubation failure in ICU patients: a prospective study. Crit Care Med 2015; 43:613. 

4. Epstein SK. Putting it all together to predict extubation outcome. Intensive Care Med 2004; 30:1255. 

5. Smina M, Salam A, Khamiees M, et al. Cough peak flows and extubation outcomes. Chest 2003; 124:262. 

Chest tube suction on expanded PTX

Q: 32 year old male is admitted to ICU after an episode of spontaneous pneumothorax (PTX). CXR normalized after insertion of chest tube. What is the danger of putting chest tube to a water seal device with suction? 



Answer: re-expansion pulmonary edema

Chest tube in patients with pneumothorax usually put connected to a water seal device. Application of suction should be applied only if there is no resolution of PTX, as there is a risk of re-expansion pulmonary edema.

#pulmonary
#procedure
#surgicalcriticalcare


Reference: 

 MacDuff A, Arnold A, Harvey J, BTS Pleural Disease Guideline Group. Management of spontaneous pneumothorax: British Thoracic Society Pleural Disease Guideline 2010. Thorax 2010; 65 Suppl 2:ii18.

DVT in burn patients

Q: Due to high risk of coagulopathy, need for frequent wound excisions, and ineffectiveness of subcutaneous (SQ) route secondary to fluid shifts - chemical deep venous thrombosis (DVT) prophylaxis should be deferred in the first week of treatment in patients with severe burn? (select one) 

A) True 
B) False 


Answer: B

Despite all challenges like a high risk of coagulopathy, need for frequent wound excisions, and possible ineffectiveness of SQ administration of chemical DVT prophylaxis secondary to fluid shifts, burn patients should not be treated differently from other ICU patients. 

The risk of DVT is higher in patients with more than 20 percent of total body surface area (TBSA) burn. 

#burn
#DVT



Reference:

Faucher LD, Conlon KM. Practice guidelines for deep venous thrombosis prophylaxis in burns. J Burn Care Res 2007; 28:661.

NAVA

Q: In neurally adjusted ventilatory assist ventilation (NAVA), electrical discharge from the diaphragm (EAdi) is detected by a catheter embedded in? 

A) Central Venous Catheter 
B) Naso-gastric tube 
C) Ventilator circuit 
D)Endo-tracheal tube (ETT) 
E) Cutaneous pacer


Answer: B

Neurally adjusted ventilatory assist ventilation (NAVA) is still an investigational mode of ventilation. It's working depends on the diaphragmatic excitation, technically known as 'electrical discharge from the diaphragm' (EAdi). The deflection above the set threshold is detected via a catheter embedded in a nasogastric tube to deliver a mechanical breath. 

NAVA is best utilized when patient-ventilator asynchrony becomes detrimental and cannot be fixed via more conventional modes of ventilation. The biggest hurdle in the use of NAVA is the requirement of spontaneously breathing patient. It cannot be used in a patient with decrease respiratory drive as in deep sedation.

#ventilator
#pulmonary


References:


1. Piquilloud L, Vignaux L, Bialais E, et al. Neurally adjusted ventilatory assist improves patient-ventilator interaction. Intensive Care Med 2011; 37:263. 

2. Schmidt M, Kindler F, Cecchini J, et al. Neurally adjusted ventilatory assist and proportional assist ventilation both improve patient-ventilator interaction. Crit Care 2015; 19:56. 

3. Demoule A, Clavel M, Rolland-Debord C, et al. Neurally adjusted ventilatory assist as an alternative to pressure support ventilation in adults: a French multicentre randomized trial. Intensive Care Med 2016; 42:1723.

CRP in pericarditis

Q: C-reactive protein (CRP) is a good marker to follow in resolution of acute pericarditis? (select one) 

 A) True 
B) False


Answer: A

Besides clinical symptoms, C-reactive protein (CRP) is an excellent marker to suggest resolution of acute pericarditis. If acute pericarditis does not get better with aspirin, colchicine or NSAIDs within 5-7 days, it suggests alternative cause other than viral or idiopathic. In such scenarios, checking CRP may be of help.

#cardiology
#laboratory-medicine


Reference:

Imazio M, Brucato A, Maestroni S, et al. Prevalence of C-reactive protein elevation and time course of normalization in acute pericarditis: implications for the diagnosis, therapy, and prognosis of pericarditis. Circulation 2011; 123:1092.

Anti-rejection meds pericarditis

Q: Cyclosporine associated pericarditis is more common after which organ transplant? (select one) 

 A) Heart 
 B) Kidney


 Answer: A

Post transplant pericarditis is common and can occur due to variety of reasons. Renal transplant patients are more at risk due to development of uremia. Other leading causes are cytomegalovirus and anti-rejection medications. 

Among anti-rejection medications, Sirolimus tends to do pericarditis more in renal transplant patients, while cyclosporine associated pericarditis is more common in post heart transplant patients.

#trasnsplant
#pharmacology
#cardiology


References: 

1. Hastillo A, Thompson JA, Lower RR, et al. Cyclosporine-induced pericardial effusion after cardiac transplantation. Am J Cardiol 1987; 59:1220.

2. Sever MS, Steinmuller DR, Hayes JM, et al. Pericarditis following renal transplantation. Transplantation 1991; 51:1229.

Diuretic induced hyponatremia

Q: Which of the diuretics tend to cause hyponatremia more?

A) Thiazide diuretics
B) Loop diuretics


Answer: A

Thiazide diuretic tends to cause hyponatremia due to their reduced diluting ability. This interferes with water excretion.This is a direct effect of reduced sodium chloride reabsorption without water in the distal tubule.

#nephrology
#lectrolytes


Reference:

Frenkel NJ, Vogt L, De Rooij SE, et al. Thiazide-induced hyponatraemia is associated with increased water intake and impaired urea-mediated water excretion at low plasma antidiuretic hormone and urine aquaporin-2. J Hypertens 2015; 33:627.

Hungry Bone Syndrome

Case: 62 year old male with End Stage Renal Disease (ESRD) is admitted to ICU after parathyroidectomy. All of the following electrolyte imbalances are expected except?

A) Hypocalcemia 
B) Hypophosphatemia 
C) Hypomagnesemia 
D) Hyperkalemia 
E) Hypernatremia


Answer:  E

The objective of the above question is to highlight the electrolyte imbalances in "Hungry Bone Syndrome" (HBS), a possible scenario after parathyroidectomy, particularly in ESRD patients. The hallmark of HBS is hypocalcemia (choice A) but other electrolyte imbalances may occur (choices B, C, D). ESRD patients are more prone to have hyponatremia due to volume-overload instead of hypernatremia (choice E).

#surgicalcriticalcare
#electrolyteimbalance
#nephrology


References:

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

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

Preserving donor lung

Q: While inflating donor lungs with oxygen, all of the following are true except?

A) It preserves the integrity of pulmonary surfactant
B) It improves the epithelial fluid transport 
C) Lung inflation is limited to an airway pressure of 20 cm H2O
D) Inflation should be done with 100% FiO2
E) Trachea should be clamped after inflation


Answer: D

Inflation of lungs with oxygen during the ischemic time protects the lungs. All of the choices are correct except it requires only 30-50% of FiO2. In fact, 100% FiO2 can be injurious due to oxygen toxicity.


#transplantation
#pulmonary


References:

1. DeCampos KN, Keshavjee S, Liu M, Slutsky AS. Optimal inflation volume for hypothermic preservation of rat lungs. J Heart Lung Transplant 1998; 17:599. 

2. Kayano K, Toda K, Naka Y, Pinsky DJ. Identification of optimal conditions for lung graft storage with Euro-Collins solution by use of a rat orthotopic lung transplant model. Circulation 1999; 100:II257.

3.  Eberlein M, Reed RM, Permutt S, et al. Parameters of donor-recipient size mismatch and survival after bilateral lung transplantation. J Heart Lung Transplant 2012; 31:1207.

Propranolol in thyroid storm

Q: Why propranolol is a preferred Beta-blocker in thyroid storm? 

Answer: Propranolol is a preferred Beta-blocker in thyroid storm because it inhibits the type 1 deiodinase, which may help reduce serum T3 level, besides treating the symptoms. Also, it can be given orally, via nasogastric route or intravenous.

#endocrine
#pharmacology


Reference:

Cooper DS, Daniels GH, Ladenson PW, Ridgway EC. Hyperthyroxinemia in patients treated with high-dose propranolol. Am J Med 1982; 73:867.

MDMA overdose

Q: 23 year old male is admitted to ICU after attending all night "circuit party" on new year's eve. Intoxication with 3,4-methylenedioxymethamphetamine (MDMA) is highly suspected. Patient starts having seizures in ICU and required intubation for the protection of airway. Patient is found to be hyperthermic at 41°C. Serum sodium is reported as 114 mEq/dL. All of the following can be administrated except?

A)  Benzodiazepines 
B) Activated charcoal 
C) Phenytoin 
D) 3% (hypertonic) saline 
E) Active external cooling


Answer:  C

MDMA, popularly known as 'Ecstasy' is a dangerous drug. It is a common drug used for "raves" or "circuit parties". Benzodiazepine is the mainstay of treatment.  Following drugs should be avoided, though clinicians may tend to use them.

• haloperidol 
• phenytoin 
• beta-blockers 
• antipyretics

Haldol may decrease the seizure threshold, interfere with heat dissipation, as well as may prolong the QTc interval. Pure beta-blockers may cause unopposed alpha-adrenergic stimulation. Seizure in MDMA intoxication is mostly due to hyponatremia and do not respond to phenytoin. Similarly, hyperthermia does not respond to antipyretics and may require active cooling.

#toxicology
#electrolyteimbalance
#neurology


References:

Kalant H. The pharmacology and toxicology of "ecstasy" (MDMA) and related drugs. CMAJ 2001; 165:917. 

Armenian P, Mamantov TM, Tsutaoka BT, et al. Multiple MDMA (Ecstasy) overdoses at a rave event: a case series. J Intensive Care Med 2013; 28:252.