Saturday, October 31, 2015

Q: In  acute decompensated pulmonary embolism (PE), how long does it take to see improvement of right ventricular (RV) function after receiving thrombolytic therapy?


Answer: About 12 hours

Patients who receives successful thrombolytic therapy usually finds improved RV function within 12 hours. In contrast, as expected patients treated only with anticoagulation may take up to one week to see improved RV function.




References:

1. Konstantinides S, Tiede N, Geibel A, et al. Comparison of alteplase versus heparin for resolution of major pulmonary embolism. Am J Cardiol 1998; 82:966. 

2. Sharma GV, Burleson VA, Sasahara AA. Effect of thrombolytic therapy on pulmonary-capillary blood volume in patients with pulmonary embolism. N Engl J Med 1980; 303:842. 

3. Come PC. Echocardiographic evaluation of pulmonary embolism and its response to therapeutic interventions. Chest 1992; 101:151S.

Friday, October 30, 2015

Q: The overall incidence of Pulmonary Embolism (PE) is higher in (choose one)

A) Male or  B) Female


Answer: Male

Contrary to popular belief - overall incidence of Pulmonary Embolism (PE) is higher in males. 

Clinical significance: During PE evaluation, same level of suspicion should be exercise for male patients as for female patients.



References:

1. Silverstein MD, Heit JA, Mohr DN, et al. Trends in the incidence of deep vein thrombosis and pulmonary embolism: a 25-year population-based study. Arch Intern Med 1998; 158:585. 

2. Naess IA, Christiansen SC, Romundstad P, et al. Incidence and mortality of venous thrombosis: a population-based study. J Thromb Haemost 2007; 5:692. 

3. Tagalakis V, Patenaude V, Kahn SR, Suissa S. Incidence of and mortality from venous thromboembolism in a real-world population: the Q-VTE Study Cohort. Am J Med 2013; 126:832.e13.

Thursday, October 29, 2015

Q: Which valve abnormality is common after insertion of continuous Left Ventricular Assist Device (LVAD)? 


Answer:  Aortic regurgitation 

 New aortic regurgitation may occur in about one fourth of patients who receives LVAD.  It may become clinically symptomatic requiring surgical fix. Temporary fix is to increase the speed of LVAD up to the point where aortic valve opening is observed under echocardiogram. This is recommended under the assumption that most aortic regurgitation after LVAD occurs in patients whose aortic valve stays closed. But permanent treatment is via surgery. Prophylactic stitch procedure at the time of LVAD insertion has also been proposed to avoid aortic regurgitation later.



References:

1.  Pak SW, Uriel N, Takayama H, et al. Prevalence of de novo aortic insufficiency during long-term support with left ventricular assist devices. J Heart Lung Transplant 2010; 29:1172.

2. Cowger J, Pagani FD, Haft JW, et al. The development of aortic insufficiency in left ventricular assist device-supported patients. Circ Heart Fail 2010; 3:668.

Wednesday, October 28, 2015

Q: Which one of the following should be avoided in patients who are at high risk of cardiogenic shock (pre-shock state) secondary to acute myocardial infarction?

A) aspirin
B) beta-blocker
C) heparin
D) intra-aortic balloon pump 
E) GP IIb/IIIa inhibitors



Answer:  B

Though beta-blockers are mainstay of treatment in coronary artery disease they can be detrimental in acute phase after acute MI, in patients who are in pre-shock state (impending cardiogenic shock). This may be due to the fact that beta-blockers have negative inotropic effect. According to COMMIT trial randomization to early beta blockade in patients who have not developed shock yet, there was a 30 percent higher occurrence of cardiogenic shock in patients 
  • Above age 70
  •  systolic blood pressure (BP) less than 120 mm Hg 
  •  heart rate greater than 110 beats per minute
  •  those with Killip Class over 1
All other choices are in fact indicated in acute MI management.



Reference: 

Chen ZM, et al. "Early intravenous then oral metoprolol in 45 852 patients with acute myocardial infarction: randomised placebo-controlled trial". The Lancet. 2005. 366(9497):1622-1632.

Tuesday, October 27, 2015

Q: 58 year old male with end stage renal disease (ESRD) developed  acute gout. All of the following can be used except

A) Glucocorticoids

B) NSAIDs 
C) Colchicine
D) Proton pump inhibitors (PPIs)
E) Acetaminophen 



Answer: C

Colchicine should be avoided in ESRD patients even if they are on hemodialysis as colchicine does not get removed by hemodialysis. Patients may develop toxicity fairly quickly. Glucocorticoids in any form i.e  intraarticular, oral or parenteral is the first line of treatment in these patients, which is in contrast to non-renal patients. Once patient is on hemodialysis NSAIDs should be ok to use in mild to moderate attacks. PPIs and acetaminophen have no contraindications in gout.


Monday, October 26, 2015

Q: All of the following are risk factors for surgical site infections (SSIs) after colorectal surgery except?

A) Perioperative blood transfusion
B) Creation of an ostomy
C) Postoperative ileus
D) Obesity
E) Male Gender



Answer:  C

Objective of above question is to highlight the danger of blood transfusion during surgery (Choice A), which is sometime taken as trivial but is an important risk factor for surgical site infections (SSIs). Some degree of postoperative ileus is expected in all colorectal surgeries (Choice C).

Creation of an ostomy, prolong immobilization, obesity and male gender are known and easy to guess risk factors for surgical site infections (SSIs).



Reference:

Tang R, Chen HH, Wang YL, et al. Risk factors for surgical site infection after elective resection of the colon and rectum: a single-center prospective study of 2,809 consecutive patients. Ann Surg 2001; 234:181.

Sunday, October 25, 2015

Q: 72 year old female who is admitted for GI bleed found to have depressed mental status in the morning. Patient received a dose of 2mg lorazepam previous night for insomnia. You suspect Lorazepam effect and called for Flumazenil. Which one added precaution should be taken in such scenarios in ICU?



Answer: Checking blood sugar

Anytime if patient is encountered with altered mental status in ICU hypoglycemia should be ruled out simultaneously. Patient in above question is admitted with GI bleed and may have nothing per mouth status (NPO).

Saturday, October 24, 2015

Q: What is the clinical significance of measuring serial serum (Lactate dehydrogenase) LDH level in Pneumocystis pneumonia (PCP) in HIV patients?



Answer: It is of prognostic significance

A rising LDH level in Pneumocystis pneumonia (PCP) in HIV patients despite appropriate treatment predicts a poor prognosis. 



References:

1. Zaman MK, White DA. Serum lactate dehydrogenase levels and Pneumocystis carinii pneumonia. Diagnostic and prognostic significance. Am Rev Respir Dis 1988; 137:796. 

2. Butt AA, Michaels S, Kissinger P. The association of serum lactate dehydrogenase level with selected opportunistic infections and HIV progression. Int J Infect Dis 2002; 6:178.

Friday, October 23, 2015

Q: 88 year old female is admitted to ICU after fall and peritrochanteric fracture as a 'soft admission'! Patient has history of coronary artery disease. Orthopedic surgeon is planning to take her to OR. All labs are essentially stable. Hemoglobin is 11.4 g/dL. Which one precaution you will add?



Answer: Type and cross and pRBC ready for OR 

Peritrochanteric hip fractures are prone for peri-operative bleeding in elderly patients. Backup should be prepared if initial hemoglobin level is below 12 g/dL



References: 

1. Dillon MF, Collins D, Rice J, et al. Preoperative characteristics identify patients with hip fractures at risk of transfusion. Clin Orthop Relat Res 2005; 439:201. 

2. Adunsky A, Lichtenstein A, Mizrahi E, et al. Blood transfusion requirements in elderly hip fracture patients. Arch Gerontol Geriatr 2003; 36:75.

Thursday, October 22, 2015

Q; 47 year old male with history of cirrhosis is admitted to ICU with exacerbation of hepatic encephalopathy. Attempts to insert naso-gastric tube to administer lactulose is unsuccessful and caused nasal bleeding due to hepatic coagulopathy. What is your other option?



Answer: Lactulose can be administered by enema.

Lactulose is a disaccharide. It acidifies the colon as it degrades. Acidification of colon causes migration of ammonia from the blood into the colon, where ammonium (NH3) get converted  to  ammonium ion (NH4) +. The trapped ammonium ion then get excreted in stool. Usual dose is to mix 300 mL of lactulose solution in 700 mL of water or saline. Solution is then administered via enema for about 30 minutes retention. Patients with high degree of coma may not be very co-operative. Also, soiling of bed, skin infection and 'mess' it creates for nursing staff, makes enema an undesirable option. Overall objective is to improve hepatic encephalopathy up to the point where patient can tolerate insertion of NGT or PO intake.


Reference: 

Raza M A, Bhatti R S, Akram J. Effect of rectal lactulose administration with oral therapy on time to recovery from hepatic encephalopathy: A randomized study. Annals of Saudi Medicine. 2004; 24(5): 374-377.

Wednesday, October 21, 2015

Q: How "principle of justice" and "principle of utility" justifies liver transplantation in alcohol induced liver failure?


Answer: 


Principle of justice argues that alcoholism is a disease process like any other disease and requires same compassion.


Compiled with -


Principle of utility, which argues that no study have so far shown that liver transplantation in alcohol induced liver failure has lesser outcome in morbidity or mortality than any other group.


Monday, October 19, 2015

Q: Permissive hypercapnia is relatively contra-indicated in all of the following except?

A) Acute myocardial infarction

B) Severe COPD

C) Active Seizure

D) Hypovolemia 

E) Bradycardia


Answer:  B

Permissive hypercapnia is usually very well tolerated by all patients but caution is required in few situations such as hypercapnia may decrease seizure threshold. Similarly, hypercapnia exacerbates vasodilation and patient should be made at least euvolemic  before allowing hypercapnia. Acute myocardial infarction may negatively get affected by hypercpania due to sympathomimetic output. Bradycardia may get worse as hypercapnia and associated acidosis has negative inotropic effects.

Hypercapnia is actually advocated in severe respiratory failure secondary to ARDS or COPD. 



References
1. Foëx P, Fordham RM. Intrinsic myocardial recovery from the negative inotropic effects of acute hypercapnia. Cardiovasc Res 1972; 6:257 

2. Feihl F, Perret C. Permissive hypercapnia. How permissive should we be? Am J Respir Crit Care Med 1994; 150:1722

3. Kavanagh BP, Laffey JG. Hypercapnia: permissive and therapeutic. Minerva Anestesiol 2006; 72:567.

Sunday, October 18, 2015

Pearls of recruitment maneuver
  1. Usually used 'rule of thumb' of  recruitment maneuver is "40-40" - application of a high level of continuous positive airway pressure of 40 cm H2O for 40 seconds, though most of the alveolar recruitment occurs during the first ten seconds of the maneuver
  2. Hypotension associated with recruitment maneuver is usually benign and recovers within 30 seconds - so don't panic.
  3. Recruitment maneuver gives best results if followed by high levels of PEEP (usually equal to more than 14-16 cm H2O)
  4. Recruitment maneuvers may essentially needed after a patient has been disconnected from the ventilator. Even few seconds without PEEP may cause alveolar collapse.

References:

 1. Fan E, Wilcox ME, Brower RG, et al. Recruitment maneuvers for acute lung injury: a systematic review. Am J Respir Crit Care Med 2008; 178:1156.


 2. Arnal JM, Paquet J, Wysocki M, et al. Optimal duration of a sustained inflation recruitment maneuver in ARDS patients. Intensive Care Med 2011; 37:1588. 


 3. Foti G, Cereda M, Sparacino ME, et al. Effects of periodic lung recruitment maneuvers on gas exchange and respiratory mechanics in mechanically ventilated acute respiratory distress syndrome (ARDS) patients. Intensive Care Med 2000; 26:501. 


4.Maggiore SM, Lellouche F, Pigeot J, et al. Prevention of endotracheal suctioning-induced alveolar derecruitment in acute lung injury. Am J Respir Crit Care Med 2003; 167:1215.

Saturday, October 17, 2015

Q: What is the usual liver function test (LFT) pattern indicative of liver failure secondary to Wilson's Disease?


Answer:  A ratio of alkaline phosphatase* to total bilirubin^ of less than four.

In Wilson's disease, LFT demonstrate total bilirubin elevation way out of proportion to alkaline phosphatase, which on the other spectrum is usually very low. 


*international units/L
^mg/dL

Friday, October 16, 2015

Q: 84 year old male is admitted to ICU with community acquired pneumonia and on Non-invasive Positive Pressure Ventilation (NIPPV). Chest X-ray shows left sided massive accumulation of pleural effusion. You want to avoid intubation. As you start draining pleural fluid, patient developed cough and complains of chest pain?



Answer:  Re-expansion pulmonary edema

Patients with large effusions are at an increased risk of reexpansion pulmonary edema, as they may develop a significant  decrease in pleural pressure even with a small amount of pleural fluid removal. While removing pleural fluid, if patient develops coughing, or complain of chest pain and shortness of breath, or if monitor shows improved oxygenation which is followed by decreased saturation - are signs of possible risks of development of  reexpansion pulmonary edema. Ideally, tube should be clamped if any sign of  reexpansion pulmonary edema and should be waited till symptoms resolved before draining further pleural fluid. Risk of reexpansion pulmonary edema can be minimized by draining not more than one litre of fluid at a time in massive pleural effusion.



References:. 


Mahfood S, Hix WR, Aaron BL, et al. Reexpansion pulmonary edema. Ann Thorac Surg 1988

Thursday, October 15, 2015

Q: All of the following are indications of Intra-Aortic Balloon Pump (IABP) except?

A)  Acute ischemic cardiogenic shock
B) Acute mitral regurgitation
C) Ventricular septal rupture
D) Left main coronary artery stenosis
E) Severe sepsis


Answer: E

IABP is a life rescuing procedure in hemodynamic instability. Being an intensivist it is of apparent importance to call for IABP if patient develops complications from acute myocardial infarction particularly if ventricular wall rupture or papillary muscle rupture. Absolute contraindication to IABP is aortic regurgitation, aortic dissection, significant aortic aneurysm, severe sepsis, clinically significant bleeding disorder or severe peripheral artery disease to insert IABP. Complications are expected in older and female patients as well as with diabetes, hypertension, requiring more than 9.5F catheter size or smaller body surface area.



Reference: 

Kushner FG, Hand M, Smith SC Jr, et al. 2009 focused updates: ACC/AHA guidelines for the management of patients with ST-elevation myocardial infarction (updating the 2004 guideline and 2007 focused update) and ACC/AHA/SCAI guidelines on percutaneous coronary intervention (updating the 2005 guideline and 2007 focused update) a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2009; 54:2205.

Wednesday, October 14, 2015

Q: Patient has been made "comfort care" due to terminal illness and neurologic coma . Family is very distressed due to persistently open eyes. How you can help patient and family?


Answer: Malnutrition leads to loss of the retro-orbital fat pad and orbit fall back posteriorly within its socket. Patient may not be able to close eyelids properly and persistently open exposure may cause conjunctival ulceration. Use of lubricants and artificial tears may prevent pain from ulceration. Simultaneously, it is important to explain the process to family and provide emotional support.

Tuesday, October 13, 2015

Q: You decided to put arterial line in dorsalis pedis artery. You get reminded by nursing student at bedside that all arterial lines should be placed after checking collateral blood flow like performing Allen test for radial artery placement. How you can perform collateral blood flow check before dorsalis artery catheter insertion?



Answer:

Occuld the dorsalis pedis artery and compress the nail bed of the great toe - relieve pressure after few seconds -. In intact collateral blood flow, color at nail bed should restore within 2-3 seconds (capillary refill). It would be of help to simultaneously perform Buerger’s Test. Raise the patient’s feet to 45 degrees. In the presence of poor arterial supply, pallor rapidly develops in feet.

Monday, October 12, 2015

Q: What are the 5 requirements of measuring bladder pressure for Intra-Abdominal Hypertension? 


Answer: As per World Society of Abdominal Compartment Syndrome (WSACS), bladder pressure should be be measured 


  • in a supine position (head of the bed no more than 20 degrees)
  • at end-expiration (absence of active abdominal muscle contraction)
  • transducer zeroed at the iliac crest in the mid-axillary line
  • Not more than 25 ml of saline should be instilled 
  • wait 30 to 60 seconds after instillation to record the pressure (allow the detrusor muscle to relax). 


Reference: 

 Malbrain ML, Cheatham ML, Kirkpatrick A, Sugrue M, Parr M, De Waele J, Balogh Z, Leppaniemi A, Olvera C, Ivatury R, D'Amours S, Wendon J, Hillman K, Johansson K, Kolkman K, Wilmer A: Results from the international conference of experts on intra-abdominal hypertension and abdominal compartment syndrome. I. definitions. Intensive Care Med 32: 1722–1732, 2006


Videohttps://youtu.be/-hLmsHtMhG0

Sunday, October 11, 2015

Q: How severity of pericardial effusion can be roughly quantified on the basis of Echocardiography?


Answer:

  • Small effusions - up to 100 ml - echo-free space  less than 10 mm in thickness at its greatest width
  • Moderate effusions - up to 500 ml - echo-free space up to 20 mm at its greatest width. 
  • Large effusions - more than 500 m -  the echo-free space is greater than 20 mm at its greatest width. 
All echo data should be read in close conjunction with clinical exams and hemodynamic data.

Saturday, October 10, 2015

10 essentials of Traumatic Brain Injury (TBI)


  1. Keep PaO2 more than 60 mmHg 
  2.  Keep systolic BP at least at 90 mmHg 
  3.  Head of bed elevation if increased intracranial pressure (ICP)  
  4.  Mannitol if increased intracranial pressure (ICP)Don't wait for CT
  5.  Target ICP is less than 20 mmHg 
  6.  Target cerebral perfusion pressure (CPP) is 60 
  7.  7 days prophylaxis of antiepileptic drugs 
  8.  Control of hyperglycemia 
  9.  Control of fever (and infection) 
  10.  DVT prophylaxis is NOT conta-indicated in TBI

Friday, October 9, 2015

Q: Which common error occurs while writing orders for "Dexmedetomidine"?


Answer: Most intravenous infusions in ICU are mcg/kg/min but Dexmedetomidine should be prescribed as mcg/kg/hour

Usual regular dose for Dexmedetomidine 0.2 to 0.7 mcg/kg/hour.


Thursday, October 8, 2015

Q: What is Paratonia?

Answer: Paratonia, also known as gegenhalten is defined as increased resistance that becomes less prominent when the patient is distracted. 

Clinical significance: It may be a sign of dementia and co-relates with the degree of dementia.


Reference: 

1.  Hobbelen, JS; Koopmans, RT, Verhey, FR, Van Peppen, RP, de Bie, RA (2006). "Paratonia: a Delphi procedure for consensus definition.". Journal of geriatric physical therapy (2001) 29 (2): 50–6

Wednesday, October 7, 2015

Q: 44 year old male with HIV is transferred from floor with respiratory failure on fourth day of hospitalization. Patient CT scan of chest has been done. Report reads: "moderate pleural effusion with thickened parietal pleura". What would be your concern?


Answer: Empyema 

In emypyema bacteria quickly get  cleared from the pleural space but there is a deposition of a dense layer of fibrin on pleurae. Thickened pleura with parapneumonic effusion is highly suggestive of empyema.



 Reference: 

 Waite RJ, Carbonneau RJ, Balikian JP, et al. Parietal pleural changes in empyema: appearances at CT. Radiology 1990; 175:145.

Tuesday, October 6, 2015

Q: All of the following are true of Primary Spontaneous Pneumothorax (PSP) except?

A) Age between 20 and 40

B) History of smoking
C) Family history
D) Physical exertion
E) Association with homocystinuria



Answer: D


Paradoxically and interestingly, Primary Spontaneous Pneumothorax (PSP) usually happens at rest. All other risk factors given above are true with PSP. It is also associated with marfan syndrome and menstruation (catamenial pneumothorax).



References;

 1. Bense L, Wiman LG, Hedenstierna G. Onset of symptoms in spontaneous pneumothorax: correlations to physical activity. Eur J Respir Dis 1987; 71:181. 

 2. Johnson MM. Catamenial pneumothorax and other thoracic manifestations of endometriosis. Clin Chest Med 2004; 25:311.

Monday, October 5, 2015

Q: 77 year old male is admitted to ICU as a pre-op for Aortic Valve Replacement. Patient previously had two times CABG (cardiac bypass)  32 year and 15 years ago respectively. Patient's pulmonary function test (PFT), CXR as well as all labs performed as outpatient are under normal parameters. Surgeon requests you to obtain CT scan of the chest. What could be the reason?



Answer: With previous multiple sternotomies, chances of peri-op bleeding may be high. Better understanding of scar  adherences via CT scan of chest in such situations may  help in minimizing  life-threatening surgical bleeding.



Reference:

Morishita K, Kawaharada N, Fukada J, et al. Three or more median sternotomies for patients with valve disease: role of computed tomography. Ann Thorac Surg 2003; 75:1476.

Sunday, October 4, 2015

Insertion of Transvenous Pacemaker

Q: Why left subclavian should be avoided for insertion of  temporary transvenous pacemaker?


Answer: Left subclavian vein should be spared for possible future permanent pacemaker placement.


 

Saturday, October 3, 2015

Q: At what level of hyperkalemia in Dig. toxicity, treatment with digoxin Fab fragments should be considered?


Answer:  Potassium level greater than 5 mEq/L 

Digoxin toxicity may rapidly cause hyperkalemia and low threshold should be kept in view of potential life threatening situations which may arise.

Every case should be individualized and all initial treatment options should be utilized as insulin with glucose, sodium bicarbonate, correcting hypomagnesemia etc. But rapidly rising potassium, arrhythmia or altered mental status should be treated with low threshold as digoxin Fab fragments is relatively a safe option though costly.



 Reference:

 Michael J. Murray, Douglas B. Coursin, Ronald G. Pearl, Donald S. Prough - Critical Care Medicine: Perioperative Management: Published under the auspices of the American Society of Critical Care Anesthesiologists (ASCCA) / Edition 2 - Page 831

Friday, October 2, 2015

Q: Pulmonary edema may occur after synchronized cardioversion in atrial fibrillation. What is the mechanism behind it?


Answer: With cardioversion in atrial fibrillation, the return of atrial systole causes a significant elevation in left atrial pressure which consequently may cause pulmonary edema. This is more common in atrial fibrillation associated with valvular heart disease or left ventricular dysfunction.



Reference: 

Gowda RM, Misra D, Khan IA, Schweitzer P. Acute pulmonary edema after cardioversion of cardiac arrhythmias. Int J Cardiol 2003; 92:271.

Thursday, October 1, 2015

Q: What is the cut off time limit between acute and chronic hypernatremia?



Answer: 48 hours

Acute hypernatremia can be treated in normal manner with goal to lower the serum sodium by 1 to 2 meq/L per hour and normonatremia can be achieved within 24 hours.

But by default all patients should be considered having chronic hypernatremia unless until proved otherwise. This is due to the fact that life threatening complications may occur due to rapid correction of chronic hypernatremia. Extreme care should be taken to not to make correction more than 10 meq/L in 24 hours.