Q: Which type of method has higher success rate during external cardioversion?
A) Hand-held
B) Self-adhesive patch
Answer: A
This is probably due to the fact that hand-held paddle during external cardioversion improves electrode-to-skin contact and reduced transthoracic impedance.
Reference:
Kirchhof P, Mönnig G, Wasmer K, et al. A trial of self-adhesive patch electrodes and hand-held paddle electrodes for external cardioversion of atrial fibrillation (MOBIPAPA). Eur Heart J 2005; 26:1292.
Wednesday, February 28, 2018
Tuesday, February 27, 2018
Five stages of hypothermia
Q: What are the five stages of hypothermia per the International Commission for Mountain Emergency Medicine (Swiss system stages)?
Answer: The International Commission for Mountain Emergency Medicine has designated following fives stages of hypothermia mostly to guide prehospital rescuers to estimate the severity of hypothermia (HT).
Durrer B, Brugger H, Syme D, International Commission for Mountain Emergency Medicine. The medical on-site treatment of hypothermia: ICAR-MEDCOM recommendation. High Alt Med Biol 2003; 4:99.
Answer: The International Commission for Mountain Emergency Medicine has designated following fives stages of hypothermia mostly to guide prehospital rescuers to estimate the severity of hypothermia (HT).
- HT I - Mild - Shivering but normal mental status - Estimated core temperature 32 to 35°C
- HT II - Moderate - No shivering but altered mental status - Estimated core temperature 28 to 32°C
- HT III - Severe - Unconscious patients -Estimated core temperature 24 to 28°C
- HT IV - Severe - Apparent death - Estimated Core temperature 13.7 to 24°C - resuscitation may be possible
- HT V - Death - Irreversible hypothermia. Core temperature - less than 9 to 13.7°C - resuscitation not possible.
References:
Monday, February 26, 2018
Age cutoff in splenic injury
Q; Why age more than 55 years is considered a high risk for failure of nonoperative management in splenic injury?
Answer: The splenic capsule thins with age and above 55 years, it becomes a risk factor for failure of nonoperative management of higher-grade splenic injuries. Above age 55, a careful decision should be made on a case by case basis to choose between operative vs nonoperative care in high-grade splenic injury.
References:
1. Siriratsivawong K, Zenati M, Watson GA, Harbrecht BG. Nonoperative management of blunt splenic trauma in the elderly: does age play a role? Am Surg 2007; 73:585.
2. Godley CD, Warren RL, Sheridan RL, McCabe CJ. Nonoperative management of blunt splenic injury in adults: age over 55 years as a powerful indicator for failure. J Am Coll Surg 1996; 183:133.
3. Krause KR, Howells GA, Bair HA, et al. Nonoperative management of blunt splenic injury in adults 55 years and older: a twenty-year experience. Am Surg 2000; 66:636.
4. Ong AW, Eilertson KE, Reilly EF, et al. Nonoperative management of splenic injuries: significance of age. J Surg Res 2016; 201:134.
Answer: The splenic capsule thins with age and above 55 years, it becomes a risk factor for failure of nonoperative management of higher-grade splenic injuries. Above age 55, a careful decision should be made on a case by case basis to choose between operative vs nonoperative care in high-grade splenic injury.
References:
1. Siriratsivawong K, Zenati M, Watson GA, Harbrecht BG. Nonoperative management of blunt splenic trauma in the elderly: does age play a role? Am Surg 2007; 73:585.
2. Godley CD, Warren RL, Sheridan RL, McCabe CJ. Nonoperative management of blunt splenic injury in adults: age over 55 years as a powerful indicator for failure. J Am Coll Surg 1996; 183:133.
3. Krause KR, Howells GA, Bair HA, et al. Nonoperative management of blunt splenic injury in adults 55 years and older: a twenty-year experience. Am Surg 2000; 66:636.
4. Ong AW, Eilertson KE, Reilly EF, et al. Nonoperative management of splenic injuries: significance of age. J Surg Res 2016; 201:134.
Sunday, February 25, 2018
Shock
Q: Traumatic brain injury can result in (select one)
A) Hypovolemic shock
B) Distributive shock
C) Cardiogenic shock
D) Obstructive shock
E) Mixed type shock
Answer: B
Objective of this question is to highlight the point that neurogenic shock is a sub-type of non-septic distributive shock.
Similarly, inflammatory shock (SIRS) as well as anaphylactic shock, liver failure, vasoplegia and beriberi are all sub-types of non-septic distributive shock.
Reference:
Vincent JL, De Backer D. Circulatory shock. N Engl J Med 2013; 369:1726.
A) Hypovolemic shock
B) Distributive shock
C) Cardiogenic shock
D) Obstructive shock
E) Mixed type shock
Answer: B
Objective of this question is to highlight the point that neurogenic shock is a sub-type of non-septic distributive shock.
Similarly, inflammatory shock (SIRS) as well as anaphylactic shock, liver failure, vasoplegia and beriberi are all sub-types of non-septic distributive shock.
Reference:
Vincent JL, De Backer D. Circulatory shock. N Engl J Med 2013; 369:1726.
Saturday, February 24, 2018
Suctioning and RSBI
Q: How long does it take after endotracheal tube (ETT) suctioning to have reliable Rapid Shallow Breathing Index (RSBI)?
Answer: Five minutes
ETT suctioning is a regular phenomenon during ventilator liberation, but it should be kept in mind that ETT suctioning increase RSBI. It takes about five minutes after ETT suctioning to get reliable RSBI.
Reference:
Seymour CW, Cross BJ, Cooke CR, et al. Physiologic impact of closed-system endotracheal suctioning in spontaneously breathing patients receiving mechanical ventilation. Respir Care 2009; 54:367.
Answer: Five minutes
ETT suctioning is a regular phenomenon during ventilator liberation, but it should be kept in mind that ETT suctioning increase RSBI. It takes about five minutes after ETT suctioning to get reliable RSBI.
Reference:
Seymour CW, Cross BJ, Cooke CR, et al. Physiologic impact of closed-system endotracheal suctioning in spontaneously breathing patients receiving mechanical ventilation. Respir Care 2009; 54:367.
Friday, February 23, 2018
Acute sarcoid arthritis in Lofgren's syndrome.
Q: 52-year-old male is admitted to ICU with severe joint pain, fever, and hypovolemia. Patient resuscitated and started on antibiotics. The patient is seen by various services and went through various tests. The final diagnosis was acute sarcoid arthritis. Which joint is mostly involved in acute sarcoid arthritis and may pinpoint towards diagnosis early in the course?
A) Knee
B) Shoulder
C) Wrist
D) Ankle
E) Pelvic
Answer: D
Acute sarcoid arthritis is a part of a triad in Lofgren's syndrome. The triad is consist of
References:
1. Abril A, Cohen MD. Rheumatologic manifestations of sarcoidosis. Curr Opin Rheumatol 2004; 16:51.
2. Grunewald J, Eklund A. Sex-specific manifestations of Löfgren's syndrome. Am J Respir Crit Care Med 2007; 175:40.
A) Knee
B) Shoulder
C) Wrist
D) Ankle
E) Pelvic
Answer: D
Acute sarcoid arthritis is a part of a triad in Lofgren's syndrome. The triad is consist of
- hilar adenopathy,
- acute arthritis, and
- erythema nodosum
References:
1. Abril A, Cohen MD. Rheumatologic manifestations of sarcoidosis. Curr Opin Rheumatol 2004; 16:51.
2. Grunewald J, Eklund A. Sex-specific manifestations of Löfgren's syndrome. Am J Respir Crit Care Med 2007; 175:40.
Thursday, February 22, 2018
Digoxin toxicity
Q: Patients with documented digoxin toxicity who receive Fab fragments should be observed in ICU for how long?
A) At least 24 hours
B) At least 48 hours
C) At least 72-96 hours
D) Once digoxin level is normalized
E) Once Fab fragment is received patient is safe to be monitored on Telemetry floor
Answer: C
Objective of above question is twofold:
1. Despite getting Fab fragments, recurrent digoxin toxicity with ventricular arrhythmia continue to occur for 72-96 hours due to digoxin's large volume of distribution. This is particularly important in patients with renal dysfunction 1.
2. Once patient receives Fab fragments, laboratory cannot read digoxin level properly and any measurement for at least seven days would be erroneous. (Choice D) 2.
References:
1. Renard C, Grene-Lerouge N, Beau N, et al. Pharmacokinetics of digoxin-specific Fab: effects of decreased renal function and age. Br J Clin Pharmacol 1997; 44:135.
2. Ujhelyi MR, Green PJ, Cummings DM, et al. Determination of free serum digoxin concentrations in digoxin toxic patients after administration of digoxin fab antibodies. Ther Drug Monit 1992; 14:147.
A) At least 24 hours
B) At least 48 hours
C) At least 72-96 hours
D) Once digoxin level is normalized
E) Once Fab fragment is received patient is safe to be monitored on Telemetry floor
Answer: C
Objective of above question is twofold:
1. Despite getting Fab fragments, recurrent digoxin toxicity with ventricular arrhythmia continue to occur for 72-96 hours due to digoxin's large volume of distribution. This is particularly important in patients with renal dysfunction 1.
2. Once patient receives Fab fragments, laboratory cannot read digoxin level properly and any measurement for at least seven days would be erroneous. (Choice D) 2.
References:
1. Renard C, Grene-Lerouge N, Beau N, et al. Pharmacokinetics of digoxin-specific Fab: effects of decreased renal function and age. Br J Clin Pharmacol 1997; 44:135.
2. Ujhelyi MR, Green PJ, Cummings DM, et al. Determination of free serum digoxin concentrations in digoxin toxic patients after administration of digoxin fab antibodies. Ther Drug Monit 1992; 14:147.
Wednesday, February 21, 2018
Adenosine in post transplanted heart
Q: Patients with the history of heart transplant have which kind of response to rapid infusion of Adenosine?
A) No response
B) Partial response
C) Suprasensitive response
D) Unpredictable response
Answer: C
Patients with cardiac transplant history usually show a suprasensitive response to adenosine. The effect of response to the drug can be threefold to fivefold. This is due to the fact that post heart transplant, the denervated donor atria, and ventricles demonstrate increased sensitivity to infusions of sympathomimetic amines.
References:
Ellenbogen KA, Thames MD, DiMarco JP, et al. Electrophysiological effects of adenosine in the transplanted human heart. Evidence of supersensitivity. Circulation 1990; 81:821.
A) No response
B) Partial response
C) Suprasensitive response
D) Unpredictable response
Answer: C
Patients with cardiac transplant history usually show a suprasensitive response to adenosine. The effect of response to the drug can be threefold to fivefold. This is due to the fact that post heart transplant, the denervated donor atria, and ventricles demonstrate increased sensitivity to infusions of sympathomimetic amines.
References:
Ellenbogen KA, Thames MD, DiMarco JP, et al. Electrophysiological effects of adenosine in the transplanted human heart. Evidence of supersensitivity. Circulation 1990; 81:821.
Tuesday, February 20, 2018
Harvey-Bradshaw Index
Q: Harvey-Bradshaw Index (HBI) is a simplified derivative of which disease to determine the severity of disease?
A) Crohn's Disease Activity Index (CDAI)
B) Severity of pneumonia index
C) ICU severity score
D) Mortality index from acute myocardial infarction
E) Post lung transplant mortality index
Answer: A
Harvey-Bradshaw Index (HBI) is a simplified derivative of the CDAI. It correlates well with CDAI. It can help ICU physicians to determine the level of urgency and choosing treatment modality. Calculators are easily available online.
Score of less than 5 on HBI is determined as clinical remission. HBI takes into account of
1. Patient sense of general well being in the last 24 hours
2. Patient report of abdominal pain in last 24 hours
3. Number of liquid stools in last 24 hours
4. Finding of an abdominal mass
5. Complications
CDAI is more extensive and complicated. It has four categories and takes into account
1. Patient reported stool pattern
2. Average abdominal pain rating over seven days
3. General well being
4. Complications
5. Finding of an abdominal mass
6. Anemia and weight change
Severity goes up with score
1. Less than 150
2. Between 151 to 220
3. Between 221 to 450
4. Above 450 (Patients with severe symptoms despite glucocorticoids or biologic agents)
References:
1. Harvey RF, Bradshaw JM. A simple index of Crohn's-disease activity. Lancet 1980; 1:514.
2. Vermeire S, Schreiber S, Sandborn WJ, et al. Correlation between the Crohn's disease activity and Harvey-Bradshaw indices in assessing Crohn's disease severity. Clin Gastroenterol Hepatol 2010; 8:357.
A) Crohn's Disease Activity Index (CDAI)
B) Severity of pneumonia index
C) ICU severity score
D) Mortality index from acute myocardial infarction
E) Post lung transplant mortality index
Answer: A
Harvey-Bradshaw Index (HBI) is a simplified derivative of the CDAI. It correlates well with CDAI. It can help ICU physicians to determine the level of urgency and choosing treatment modality. Calculators are easily available online.
Score of less than 5 on HBI is determined as clinical remission. HBI takes into account of
1. Patient sense of general well being in the last 24 hours
2. Patient report of abdominal pain in last 24 hours
3. Number of liquid stools in last 24 hours
4. Finding of an abdominal mass
5. Complications
CDAI is more extensive and complicated. It has four categories and takes into account
1. Patient reported stool pattern
2. Average abdominal pain rating over seven days
3. General well being
4. Complications
5. Finding of an abdominal mass
6. Anemia and weight change
Severity goes up with score
1. Less than 150
2. Between 151 to 220
3. Between 221 to 450
4. Above 450 (Patients with severe symptoms despite glucocorticoids or biologic agents)
References:
1. Harvey RF, Bradshaw JM. A simple index of Crohn's-disease activity. Lancet 1980; 1:514.
2. Vermeire S, Schreiber S, Sandborn WJ, et al. Correlation between the Crohn's disease activity and Harvey-Bradshaw indices in assessing Crohn's disease severity. Clin Gastroenterol Hepatol 2010; 8:357.
Monday, February 19, 2018
Jolt accentuation of a headache
Q: Jolt accentuation of a headache on physical exam raises the possibility of
A) A retinal migraine
B) Meningitis
C) Intra-cranial mass
D) Cervical radiculopathy
E) Subarachnoid hemmorhage
Answer: B
Although Brudzinski and the Kernig signs have been described as the classic for meningitis, jolt accentuation o a headache may be easier to perform and can be more sensitive 1. It is considered positive if accentuation of a headache occurs by horizontal rotation of the head at a frequency of 2-3/sec. This does not confirm or rule out 2 the diagnosis of meningitis but may make the patient eligible for a lumbar puncture (LP).
References:
1. Uchihara T, Tsukagoshi H. Jolt accentuation of headache: the most sensitive sign of CSF pleocytosis. Headache 1991; 31:167.
2. Tamune H, Takeya H, Suzuki W, et al. Absence of jolt accentuation of headache cannot accurately rule out meningitis in adults. Am J Emerg Med 2013; 31:1601.
A) A retinal migraine
B) Meningitis
C) Intra-cranial mass
D) Cervical radiculopathy
E) Subarachnoid hemmorhage
Answer: B
Although Brudzinski and the Kernig signs have been described as the classic for meningitis, jolt accentuation o a headache may be easier to perform and can be more sensitive 1. It is considered positive if accentuation of a headache occurs by horizontal rotation of the head at a frequency of 2-3/sec. This does not confirm or rule out 2 the diagnosis of meningitis but may make the patient eligible for a lumbar puncture (LP).
References:
1. Uchihara T, Tsukagoshi H. Jolt accentuation of headache: the most sensitive sign of CSF pleocytosis. Headache 1991; 31:167.
2. Tamune H, Takeya H, Suzuki W, et al. Absence of jolt accentuation of headache cannot accurately rule out meningitis in adults. Am J Emerg Med 2013; 31:1601.
Sunday, February 18, 2018
Postprandial hypotension in ESRD patients
Scenario; 62-year-old male with End Stage Renal Disease (ESRD) is admitted in ICU for community-acquired pneumonia. The patient is responding to antibiotics. Patient in ICU previously had two episodes of hypotension while in hemodialysis (HD) session, requiring stoppage of HD and infusion of a fluid bolus. Today Nephrology service wrote orders to hold food before and while the patient is in HD session?
Explanation: Studies have shown that peripheral vascular resistance (PVR) drops 20 to 120 minutes after the ingestion of food, and this effect may be pronounced in chronic ESRD patients, on HD due to autonomic dysfunction. This is one easy trick which can be useful in ICU :)
References:
1. Barakat MM, Nawab ZM, Yu AW, et al. Hemodynamic effects of intradialytic food ingestion and the effects of caffeine. J Am Soc Nephrol 1993; 3:1813.
2. Sherman RA, Torres F, Cody RP. Postprandial blood pressure changes during hemodialysis. Am J Kidney Dis 1988; 12:37.
3. Kearney MT, Cowley AJ, Stubbs TA, et al. Depressor action of insulin on skeletal muscle vasculature: a novel mechanism for postprandial hypotension in the elderly. J Am Coll Cardiol 1998; 31:209.
Explanation: Studies have shown that peripheral vascular resistance (PVR) drops 20 to 120 minutes after the ingestion of food, and this effect may be pronounced in chronic ESRD patients, on HD due to autonomic dysfunction. This is one easy trick which can be useful in ICU :)
References:
1. Barakat MM, Nawab ZM, Yu AW, et al. Hemodynamic effects of intradialytic food ingestion and the effects of caffeine. J Am Soc Nephrol 1993; 3:1813.
2. Sherman RA, Torres F, Cody RP. Postprandial blood pressure changes during hemodialysis. Am J Kidney Dis 1988; 12:37.
3. Kearney MT, Cowley AJ, Stubbs TA, et al. Depressor action of insulin on skeletal muscle vasculature: a novel mechanism for postprandial hypotension in the elderly. J Am Coll Cardiol 1998; 31:209.
Saturday, February 17, 2018
enteral formula for chylous situations
Q: Which of the following enteral formula may be useful in chylothorax or chylous ascites?
A) Standard
B) Concentrated
C) Predigested
D) Patient should be kept NPO
E) Only nocturnal enteral nutrition
Answer: C
Predigested enteral nutrition is also known as a semi-elemental or elemental formula. The main focus in this formula is on decreased fat with increased medium-chain triglycerides (MCTs). Also, the protein is hydrolyzed to short-chain peptides and a less complex form of carbohydrate is included. MCTs can't enter lymphatic capillaries in the small intestine and are advocated in patients with thoracic duct leak, chylothorax or chylous ascites. They are also recommended in malabsorptive syndromes, short gut syndromes, unresponsive gut to pancreatic enzymes supplements, and persistent diarrhea from standard enteral nutrition in ICU. As the name implies, they are like a digested form of enteral nutrition and better tolerated by the digestive system.
Abovesaid, evidence for its regular use in ICU is still weak.
References:
Seres DS, Ippolito PR. Pilot study evaluating the efficacy, tolerance and safety of a peptide-based enteral formula versus a high protein enteral formula in multiple ICU settings (medical, surgical, cardiothoracic). Clin Nutr 2017; 36:706.
A) Standard
B) Concentrated
C) Predigested
D) Patient should be kept NPO
E) Only nocturnal enteral nutrition
Answer: C
Predigested enteral nutrition is also known as a semi-elemental or elemental formula. The main focus in this formula is on decreased fat with increased medium-chain triglycerides (MCTs). Also, the protein is hydrolyzed to short-chain peptides and a less complex form of carbohydrate is included. MCTs can't enter lymphatic capillaries in the small intestine and are advocated in patients with thoracic duct leak, chylothorax or chylous ascites. They are also recommended in malabsorptive syndromes, short gut syndromes, unresponsive gut to pancreatic enzymes supplements, and persistent diarrhea from standard enteral nutrition in ICU. As the name implies, they are like a digested form of enteral nutrition and better tolerated by the digestive system.
Abovesaid, evidence for its regular use in ICU is still weak.
References:
Seres DS, Ippolito PR. Pilot study evaluating the efficacy, tolerance and safety of a peptide-based enteral formula versus a high protein enteral formula in multiple ICU settings (medical, surgical, cardiothoracic). Clin Nutr 2017; 36:706.
Friday, February 16, 2018
Warfarin
Q: All of the following can be the side-effects of warfarin except?
A) Bleeding
B) Skin necrosis
C) Teratogenicity during pregnancy
D) Cholesterol embolization
E) Vascular de-calcification
Answer: E
Instead of vascular de-calcification, actually vascular calcification has been seen in patient on warfarin therapy. It can be seen in aortic valve, coronary arteries, femoral artery. The mechanism of action is the inhibition of a vitamin K dependent matrix Gla protein. It's correlation with clinical outcomes such as stroke or coronary events is still not validated.
References:
1. Koos R, Mahnken AH, Mühlenbruch G, et al. Relation of oral anticoagulation to cardiac valvular and coronary calcium assessed by multislice spiral computed tomography. Am J Cardiol 2005; 96:747.
2. Koos R, Krueger T, Westenfeld R, et al. Relation of circulating Matrix Gla-Protein and anticoagulation status in patients with aortic valve calcification. Thromb Haemost 2009; 101:706.
3. Rennenberg RJ, van Varik BJ, Schurgers LJ, et al. Chronic coumarin treatment is associated with increased extracoronary arterial calcification in humans. Blood 2010; 115:5121.
A) Bleeding
B) Skin necrosis
C) Teratogenicity during pregnancy
D) Cholesterol embolization
E) Vascular de-calcification
Answer: E
Instead of vascular de-calcification, actually vascular calcification has been seen in patient on warfarin therapy. It can be seen in aortic valve, coronary arteries, femoral artery. The mechanism of action is the inhibition of a vitamin K dependent matrix Gla protein. It's correlation with clinical outcomes such as stroke or coronary events is still not validated.
References:
1. Koos R, Mahnken AH, Mühlenbruch G, et al. Relation of oral anticoagulation to cardiac valvular and coronary calcium assessed by multislice spiral computed tomography. Am J Cardiol 2005; 96:747.
2. Koos R, Krueger T, Westenfeld R, et al. Relation of circulating Matrix Gla-Protein and anticoagulation status in patients with aortic valve calcification. Thromb Haemost 2009; 101:706.
3. Rennenberg RJ, van Varik BJ, Schurgers LJ, et al. Chronic coumarin treatment is associated with increased extracoronary arterial calcification in humans. Blood 2010; 115:5121.
Thursday, February 15, 2018
Drug level monitoring in ICU
Q: End-stage renal disease (ESRD) and AKI can also effect hepatic drug metabolism?
A) True
B) False
Answer: True
An important but not always appreciated fact in the ICU is that liver drug metabolism may also change in patients who develop acute kidney injury (AKI). Overall, end-stage renal disease (ESRD) and AKI both reduce hepatic drug metabolism. It calls for close vigilance of drugs level monitoring, irrespective of route of excretion.
Reference:
1. Vilay AM, Churchwell MD, Mueller BA. Clinical review: Drug metabolism and nonrenal clearance in acute kidney injury. Crit Care 2008; 12:235.
A) True
B) False
Answer: True
An important but not always appreciated fact in the ICU is that liver drug metabolism may also change in patients who develop acute kidney injury (AKI). Overall, end-stage renal disease (ESRD) and AKI both reduce hepatic drug metabolism. It calls for close vigilance of drugs level monitoring, irrespective of route of excretion.
Reference:
1. Vilay AM, Churchwell MD, Mueller BA. Clinical review: Drug metabolism and nonrenal clearance in acute kidney injury. Crit Care 2008; 12:235.
Wednesday, February 14, 2018
Hyperfusion syndrome after CEA
Q: Why it is important to have a tight blood pressure control after carotid endarterectomy (CEA)?
Answer: Hypertension is a predecessor of the hyperfusion syndrome after CEA. Though it is not a common sequela of post CEA, but it can be devastating causing intracerebral hemorrhage (ICH) and seizures. It mostly occurs in first 2 weeks of the procedure. This is due to the restoration of blood flow within the previously hypoperfused cerebral hemisphere, where vessels may have lost the capacity to autoregulate. Peri and post operative BP control can prevent that. Risk factors are high-grade stenosis, carotid lesion, and recent stroke. Clinical sign is ipsilateral headache to the revascularized side which improves at upright posture. Other clinical signs are focal motor seizures, and postictal Todd's paralysis.
References:
1. Coutts SB, Hill MD, Hu WY. Hyperperfusion syndrome: toward a stricter definition. Neurosurgery 2003; 53:1053.
2. Bouri S, Thapar A, Shalhoub J, et al. Hypertension and the post-carotid endarterectomy cerebral hyperperfusion syndrome. Eur J Vasc Endovasc Surg 2011; 41:229.
3. Piepgras DG, Morgan MK, Sundt TM Jr, et al. Intracerebral hemorrhage after carotid endarterectomy. J Neurosurg 1988; 68:532.
4. Karapanayiotides T, Meuli R, Devuyst G, et al. Postcarotid endarterectomy hyperperfusion or reperfusion syndrome. Stroke 2005; 36:21.
Answer: Hypertension is a predecessor of the hyperfusion syndrome after CEA. Though it is not a common sequela of post CEA, but it can be devastating causing intracerebral hemorrhage (ICH) and seizures. It mostly occurs in first 2 weeks of the procedure. This is due to the restoration of blood flow within the previously hypoperfused cerebral hemisphere, where vessels may have lost the capacity to autoregulate. Peri and post operative BP control can prevent that. Risk factors are high-grade stenosis, carotid lesion, and recent stroke. Clinical sign is ipsilateral headache to the revascularized side which improves at upright posture. Other clinical signs are focal motor seizures, and postictal Todd's paralysis.
References:
1. Coutts SB, Hill MD, Hu WY. Hyperperfusion syndrome: toward a stricter definition. Neurosurgery 2003; 53:1053.
2. Bouri S, Thapar A, Shalhoub J, et al. Hypertension and the post-carotid endarterectomy cerebral hyperperfusion syndrome. Eur J Vasc Endovasc Surg 2011; 41:229.
3. Piepgras DG, Morgan MK, Sundt TM Jr, et al. Intracerebral hemorrhage after carotid endarterectomy. J Neurosurg 1988; 68:532.
4. Karapanayiotides T, Meuli R, Devuyst G, et al. Postcarotid endarterectomy hyperperfusion or reperfusion syndrome. Stroke 2005; 36:21.
Tuesday, February 13, 2018
Akinetic mutism
Q: Akinetic mutism is due to injury to which part of the brain?
A) Temporal lobe
B) Parietal lobe
C) Frontal lobe
D) Occipital lobe
E) It is a psychiatric phenomenon
Answer: C
The objective of above question is to highlight a relatively less known phenomenon, akinetic mutism after a neurological insult. Due to injury to the frontal lobe, a patient does not initiate speech or movements.
In akinetic mutism, a patient is not paralyzed but lack willingness. Alertness is present and patients' eyes may follow their observer or they may respond to audio clues. There are two kinds of akinetic mutism described. 1) Frontal or hyperpathic akinetic mutism as described above 2) Mesencephalic or somnolent akinetic mutism due to damage to the midbrain, where vertical gaze palsy and ophthalmoplegia can usually be demonstrated.
This is completely a distinct phenomenon. After an event of neural insult, a careful determination should be performed to differentiate between coma, persistent vegetative state, brain death, locked-in syndrome (coma vigilante) and dementia, as they all have different management and outcomes.
Treatment with intravenous magnesium sulfate has been said to be beneficial.
References:
Laureys S, Owen AM, Schiff ND. Brain function in coma, vegetative state, and related disorders. Lancet Neurol 2004; 3:537.
Nagaratnam, Nages; Kujan Nagaratnam; Kevin Ng; Patrick Diu (2004). "Akinetic mutism following stroke". Journal of Clinical Neuroscience. 11 (1): 25–30.Rozen, Todd (2012).
"Rapid resolution of akinetic mutism in delayed post-hypoxic leukoencephalopathy with intravenous magnesium sulfate". Neurorehabilitation. 30 (4): 329–332
A) Temporal lobe
B) Parietal lobe
C) Frontal lobe
D) Occipital lobe
E) It is a psychiatric phenomenon
Answer: C
The objective of above question is to highlight a relatively less known phenomenon, akinetic mutism after a neurological insult. Due to injury to the frontal lobe, a patient does not initiate speech or movements.
In akinetic mutism, a patient is not paralyzed but lack willingness. Alertness is present and patients' eyes may follow their observer or they may respond to audio clues. There are two kinds of akinetic mutism described. 1) Frontal or hyperpathic akinetic mutism as described above 2) Mesencephalic or somnolent akinetic mutism due to damage to the midbrain, where vertical gaze palsy and ophthalmoplegia can usually be demonstrated.
This is completely a distinct phenomenon. After an event of neural insult, a careful determination should be performed to differentiate between coma, persistent vegetative state, brain death, locked-in syndrome (coma vigilante) and dementia, as they all have different management and outcomes.
Treatment with intravenous magnesium sulfate has been said to be beneficial.
References:
Laureys S, Owen AM, Schiff ND. Brain function in coma, vegetative state, and related disorders. Lancet Neurol 2004; 3:537.
Nagaratnam, Nages; Kujan Nagaratnam; Kevin Ng; Patrick Diu (2004). "Akinetic mutism following stroke". Journal of Clinical Neuroscience. 11 (1): 25–30.Rozen, Todd (2012).
"Rapid resolution of akinetic mutism in delayed post-hypoxic leukoencephalopathy with intravenous magnesium sulfate". Neurorehabilitation. 30 (4): 329–332
Monday, February 12, 2018
Dialysis Catheter which did not work (case report)
Case:
A 66YO man admitted for a septic shock with acute kidney failure. A dialysis catheter was placed in the left internal jugular vein using ultrasound guidance. Abnormal positioning of the catheter was suspected after technical difficulty in initiating dialysis.
Reference:
Wissanji, T., Wang, H.T. & Marquis, F. Intensive Care Med (2018). https://doi.org/10.1007/s00134-018-5058-3
A 66YO man admitted for a septic shock with acute kidney failure. A dialysis catheter was placed in the left internal jugular vein using ultrasound guidance. Abnormal positioning of the catheter was suspected after technical difficulty in initiating dialysis.
Reference:
Wissanji, T., Wang, H.T. & Marquis, F. Intensive Care Med (2018). https://doi.org/10.1007/s00134-018-5058-3
Sunday, February 11, 2018
Serotonin Syndrome
Q: All of the following are relatively contra-indicated in Serotonin Syndrome (SS) except?
A) Cyproheptadine
B) Propranolol
C) Bromocriptine
D) Dantrolene
E) Chlorpromazine
Answer: A
Out of all of the above, Cyproheptadine is established as an antidote for SS. Cyproheptadine is a histamine-1 receptor antagonist as well as has anticholinergic activity. Benzodiazepines can also be used to control agitation.
Olanzapine is also recommended to counter SS but data is not convincing.
Chlorpromazine may increase hyperthermia.
Interestingly in SS, monitoring of tachycardia is used to gauge the effectiveness of treatment. Propranolol can mask tachycardia. Also, it can induce prolong hypotension due to it's prolong half life.
Bromocriptine is a serotonin agonist! - and should be avoided.
Dantrolene has no role in SS.
References:
1. Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med 2005; 352:1112.
2. Graudins A, Stearman A, Chan B. Treatment of the serotonin syndrome with cyproheptadine. J Emerg Med 1998; 16:615.
3. Gillman PK. The serotonin syndrome and its treatment. J Psychopharmacol 1999; 13:100.
4. McDaniel WW. Serotonin syndrome: early management with cyproheptadine. Ann Pharmacother 2001; 35:870.
A) Cyproheptadine
B) Propranolol
C) Bromocriptine
D) Dantrolene
E) Chlorpromazine
Answer: A
Out of all of the above, Cyproheptadine is established as an antidote for SS. Cyproheptadine is a histamine-1 receptor antagonist as well as has anticholinergic activity. Benzodiazepines can also be used to control agitation.
Olanzapine is also recommended to counter SS but data is not convincing.
Chlorpromazine may increase hyperthermia.
Interestingly in SS, monitoring of tachycardia is used to gauge the effectiveness of treatment. Propranolol can mask tachycardia. Also, it can induce prolong hypotension due to it's prolong half life.
Bromocriptine is a serotonin agonist! - and should be avoided.
Dantrolene has no role in SS.
References:
1. Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med 2005; 352:1112.
2. Graudins A, Stearman A, Chan B. Treatment of the serotonin syndrome with cyproheptadine. J Emerg Med 1998; 16:615.
3. Gillman PK. The serotonin syndrome and its treatment. J Psychopharmacol 1999; 13:100.
4. McDaniel WW. Serotonin syndrome: early management with cyproheptadine. Ann Pharmacother 2001; 35:870.
Saturday, February 10, 2018
Negative U wave on EKG
Q: Negative U wave on EKG during exercise testing correlates with stenosis of which coronary vessels?
A) The left main
B) Left anterior descending coronary artery (LAD)
C) Posterior descending artery
D) A and B
E) All of the above
Answer: D
U waves on EKG are usually positive deflections and best visible on leads V2 to V4. They are well known in clinical practice due to their association with hypokalemia and intracranial hemorrhage. U wave's polarity may reverse during myocardial ischemia. Negative U waves during exercise stress test is highly suggestive of ischemia from left main or LAD artery.
A) The left main
B) Left anterior descending coronary artery (LAD)
C) Posterior descending artery
D) A and B
E) All of the above
Answer: D
U waves on EKG are usually positive deflections and best visible on leads V2 to V4. They are well known in clinical practice due to their association with hypokalemia and intracranial hemorrhage. U wave's polarity may reverse during myocardial ischemia. Negative U waves during exercise stress test is highly suggestive of ischemia from left main or LAD artery.
Friday, February 9, 2018
Undesirable effects of mechanical ventilation
Q: All of the following are the effects of Positive Pressure Ventilation (PPV) except?
A) Decreased dead space
B) Reduced intraparenchymal shunt
C) Diaphragmatic dysfunction
D) Respiratory muscle atrophy
E) Impaired mucociliary motility
Answer: A
Prolonged positive pressure ventilation is associated with many undesirable effects including all of the following except choice A. Positive pressure ventilation increases ventilation (V) in alveoli that do not have a corresponding increase in perfusion (Q). It causes increased V/Q mismatch and increased dead space. The ultimate effect could become evident as hypercapnia in Arterial-Blood-Gases (ABGs).
A) Decreased dead space
B) Reduced intraparenchymal shunt
C) Diaphragmatic dysfunction
D) Respiratory muscle atrophy
E) Impaired mucociliary motility
Answer: A
Prolonged positive pressure ventilation is associated with many undesirable effects including all of the following except choice A. Positive pressure ventilation increases ventilation (V) in alveoli that do not have a corresponding increase in perfusion (Q). It causes increased V/Q mismatch and increased dead space. The ultimate effect could become evident as hypercapnia in Arterial-Blood-Gases (ABGs).
Thursday, February 8, 2018
End of life care _SUPPORT study
Q: "Maintaining a sense of humor" is part of a good death process?
A) True
B) False
Answer: True
According to SUPPORT (Study to Understand Prognosis and Preferences for Outcomes and Risks of Treatments) study in which older adults facing the end of life offered insight into a good death as they experienced their own dying, there were 19 expectations / recommendations /desires divided into five components
1. Care related to symptoms and personal care
2. Being prepared for death
3. Achieving a sense of completion
4. Being treated as a whole person
5. Relating to family, society, care providers, and transcendent
"Maintaining a sense of humor" is considered as one of the part from dying patients in #4 component.
Reference:
Steinhauser KE, Christakis NA, Clipp EC, et al. Factors considered important at the end of life by patients, family, physicians, and other care providers. JAMA 2000; 284:2476.
A) True
B) False
Answer: True
According to SUPPORT (Study to Understand Prognosis and Preferences for Outcomes and Risks of Treatments) study in which older adults facing the end of life offered insight into a good death as they experienced their own dying, there were 19 expectations / recommendations /desires divided into five components
1. Care related to symptoms and personal care
2. Being prepared for death
3. Achieving a sense of completion
4. Being treated as a whole person
5. Relating to family, society, care providers, and transcendent
"Maintaining a sense of humor" is considered as one of the part from dying patients in #4 component.
Reference:
Steinhauser KE, Christakis NA, Clipp EC, et al. Factors considered important at the end of life by patients, family, physicians, and other care providers. JAMA 2000; 284:2476.
Wednesday, February 7, 2018
Temperature measurement in hypothermic patients
Q: Which of the following method is most reliable to measure the rewarming phase in a severely hypothermic patient who is intubated?
A) Rectal
B) Bladder
C) Infra-red temporal artery
D) Lower one-third of the esophagus
E) Axillary
Answer: D
In patients with severe hypothermia lower one-third of the esophagus, and to be precise 24 cm below the larynx, is the most reliable method to track the rewarming phase. This area provides the best surrogate of the cardiac temperature. Upper one-third of the esophagus may be falsely elevated due to humidified (heated) oxygen in the endotracheal-tube (ETT). Though rectal and bladder probes are commonly used and good for mild to moderate hypothermia, but they lag behind in the rewarming phase. Axillary and temporal artery measurement of temperature are external to the body and should not be used.
Reference:
Danzl D. Accidental hypothermia. In: Wilderness Medicine, 6th ed, Auerbach PS (Ed), Elsevier, Philadelphia 2012. p.115.
A) Rectal
B) Bladder
C) Infra-red temporal artery
D) Lower one-third of the esophagus
E) Axillary
Answer: D
In patients with severe hypothermia lower one-third of the esophagus, and to be precise 24 cm below the larynx, is the most reliable method to track the rewarming phase. This area provides the best surrogate of the cardiac temperature. Upper one-third of the esophagus may be falsely elevated due to humidified (heated) oxygen in the endotracheal-tube (ETT). Though rectal and bladder probes are commonly used and good for mild to moderate hypothermia, but they lag behind in the rewarming phase. Axillary and temporal artery measurement of temperature are external to the body and should not be used.
Reference:
Danzl D. Accidental hypothermia. In: Wilderness Medicine, 6th ed, Auerbach PS (Ed), Elsevier, Philadelphia 2012. p.115.
Tuesday, February 6, 2018
Pad size on cardioversion
Q: During external electric cardioversion which size of electrode pad is preferred (select one)
A) Bigger size
B) Smaller size
Answer: A
Larger size of electrode pad (usually 12-13 cm in diameter) provides larger paddle surface area, which results in decrease resistance and increase current and may cause less cardiac muscle necrosis.
References:
1. Thomas ED, Ewy GA, Dahl CF, Ewy MD. Effectiveness of direct current defibrillation: role of paddle electrode size. Am Heart J 1977; 93:463.
2. Ewy GA, Horan WJ. Effectiveness of direct current defibrillation: role of paddle electrode size: II. Am Heart J 1977; 93:674.
3. Dahl CF, Ewy GA, Warner ED, Thomas ED. Myocardial necrosis from direct current countershock. Effect of paddle electrode size and time interval between discharges. Circulation 1974; 50:956.
A) Bigger size
B) Smaller size
Answer: A
Larger size of electrode pad (usually 12-13 cm in diameter) provides larger paddle surface area, which results in decrease resistance and increase current and may cause less cardiac muscle necrosis.
References:
1. Thomas ED, Ewy GA, Dahl CF, Ewy MD. Effectiveness of direct current defibrillation: role of paddle electrode size. Am Heart J 1977; 93:463.
2. Ewy GA, Horan WJ. Effectiveness of direct current defibrillation: role of paddle electrode size: II. Am Heart J 1977; 93:674.
3. Dahl CF, Ewy GA, Warner ED, Thomas ED. Myocardial necrosis from direct current countershock. Effect of paddle electrode size and time interval between discharges. Circulation 1974; 50:956.
Monday, February 5, 2018
Classic phrase for embolic stroke
Q: Stroke precipitated with a history of "getting up at night to urinate" is classic of which kind of stroke?
A) Intracerebral hemorrhage (ICH)
B) Subarachnoid hemorrhage (SAH)
C) Thrombotic stroke
D) Embolic stroke
E) Transient ischemic attack (TIA)
Answer: D
In contrast to ICH/SAH which are classic to precipitate secondary to sexual or physical activity, embolic stroke is classic with the history of precipitated by "getting up at night to urinate". Some patients may report activity like forceful sneezing or cough. Also, embolic strokes in contrast to thrombotic strokes are described with three of the following characteristics:
A) Intracerebral hemorrhage (ICH)
B) Subarachnoid hemorrhage (SAH)
C) Thrombotic stroke
D) Embolic stroke
E) Transient ischemic attack (TIA)
Answer: D
In contrast to ICH/SAH which are classic to precipitate secondary to sexual or physical activity, embolic stroke is classic with the history of precipitated by "getting up at night to urinate". Some patients may report activity like forceful sneezing or cough. Also, embolic strokes in contrast to thrombotic strokes are described with three of the following characteristics:
- tends to occur suddenly
- maximal at onset
- rapid recovery
Sunday, February 4, 2018
Pupillary reaction through the different stages of hepatic encephalopathy
Q: How the pupillary reaction progresses through the different stages of hepatic encephalopathy?
Answer:
Close monitoring of pupillary changes is an integral and essential part of the management of hepatic encephalopathy as it signifies the level of increased intracranial pressure.
References / further read:
1. Shawcross DL, Wendon JA. The neurological manifestations of acute liver failure. Neurochem Int. 2012 Jun;60(7):662-71.
2. Eelco F.M. Wijdicks, M.D., Ph.D. .N Engl J Med 2016; 375:1660-1670
Answer:
Close monitoring of pupillary changes is an integral and essential part of the management of hepatic encephalopathy as it signifies the level of increased intracranial pressure.
- A normal response = grade I encephalopathy
- Hyperresponsive = grade II to III encephalopathy
- Slowly responsive = grade III to IV encephalopathy
- Fixed and dilated = probable brainstem herniation
1. Shawcross DL, Wendon JA. The neurological manifestations of acute liver failure. Neurochem Int. 2012 Jun;60(7):662-71.
2. Eelco F.M. Wijdicks, M.D., Ph.D. .N Engl J Med 2016; 375:1660-1670
Saturday, February 3, 2018
Toxoplasmosis in Post Heart Transplant
Q: In which of the following, there is the highest incidence of Toxoplasmosis, post Solid Organ Transplants (SOT)?
A) Kidney
B) Liver
C) Heart
D) Pancrease
E) Lung
Answer: C
Out of all, the post cardiac transplant patients have shown to have the highest incidence of toxoplasmosis. This may be due to the fact that parasitic cysts can reside in the myocardium. Often it occurs within 90 days of the transplantation and presents with mental status change (encephalopathy). Hallmark of this disease with ring-enhancing lesions can be seen on MRI of the brain.
Reference:
Munoz P, Valerio M, Palomo J, et al. Infectious and non-infectious neurologic complications in heart transplant recipients. Medicine (Baltimore). 2010;89(3):166–175
A) Kidney
B) Liver
C) Heart
D) Pancrease
E) Lung
Answer: C
Out of all, the post cardiac transplant patients have shown to have the highest incidence of toxoplasmosis. This may be due to the fact that parasitic cysts can reside in the myocardium. Often it occurs within 90 days of the transplantation and presents with mental status change (encephalopathy). Hallmark of this disease with ring-enhancing lesions can be seen on MRI of the brain.
Reference:
Munoz P, Valerio M, Palomo J, et al. Infectious and non-infectious neurologic complications in heart transplant recipients. Medicine (Baltimore). 2010;89(3):166–175
Friday, February 2, 2018
Ocular Sonography in Elevated ICP
Q: How ocular sonography can be of help in Neuro-Critical-Care?
Answer: Biggest advantage of ocular sonography is that it is non-invasive. It can measure the diameter of optic nerve sheath, which correlates with intracranial pressure (ICP). Literature is conflicting in establishing the cutoff point but diameter above 5.5 mm is found to have a high sensitivity and specificity for ICP of >20 cm H2O.
References:
1. Amini A, Kariman H, Arhami Dolatabadi A, Hatamabadi HR, Derakhshanfar H, Mansouri B, et al. Use of the sonographic diameter of optic nerve sheath to estimate intracranial pressure. Am J Emerg Med. 2013;31:236–9.
2. Soldatos T, Karakitsos D, Chatzimichail K, et al. Optic nerve sonography in the diagnostic evaluation of adult brain injury. Crit Care 2008; 12:R67.
3. Dubourg J, Javouhey E, Geeraerts T, et al. Ultrasonography of optic nerve sheath diameter for detection of raised intracranial pressure: a systematic review and meta-analysis. Intensive Care Med 2011; 37:1059.
Answer: Biggest advantage of ocular sonography is that it is non-invasive. It can measure the diameter of optic nerve sheath, which correlates with intracranial pressure (ICP). Literature is conflicting in establishing the cutoff point but diameter above 5.5 mm is found to have a high sensitivity and specificity for ICP of >20 cm H2O.
References:
1. Amini A, Kariman H, Arhami Dolatabadi A, Hatamabadi HR, Derakhshanfar H, Mansouri B, et al. Use of the sonographic diameter of optic nerve sheath to estimate intracranial pressure. Am J Emerg Med. 2013;31:236–9.
2. Soldatos T, Karakitsos D, Chatzimichail K, et al. Optic nerve sonography in the diagnostic evaluation of adult brain injury. Crit Care 2008; 12:R67.
3. Dubourg J, Javouhey E, Geeraerts T, et al. Ultrasonography of optic nerve sheath diameter for detection of raised intracranial pressure: a systematic review and meta-analysis. Intensive Care Med 2011; 37:1059.
Thursday, February 1, 2018
Seizure in mushroom poisoning
Q: What is the drug of choice in a patient who get admitted to ICU with poisonous mushroom ingestion, develop seizures which does not respond to standard anti-seizure medications?
Answer: Pyridoxine
Gyromitrin containing mushrooms are more prone to cause seizures. Usually benzodiazepines works well to control seizures. But if patient does not respond to standard anticonvulsants, pyridoxine is the next choice. Usual dose is 5 grams. Pyridoxine works via its involvement in synthesis of GABA within CNS and works well if administrated with benzodiazepines.
Reference:
Michelot D, Toth B. Poisoning by Gyromitra esculenta--a review. J Appl Toxicol 1991; 11:235.
Answer: Pyridoxine
Gyromitrin containing mushrooms are more prone to cause seizures. Usually benzodiazepines works well to control seizures. But if patient does not respond to standard anticonvulsants, pyridoxine is the next choice. Usual dose is 5 grams. Pyridoxine works via its involvement in synthesis of GABA within CNS and works well if administrated with benzodiazepines.
Reference:
Michelot D, Toth B. Poisoning by Gyromitra esculenta--a review. J Appl Toxicol 1991; 11:235.
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