Saturday, December 20, 2008

Neuroanaesthesia Quiz




Recently I conducted a neuroanaesthesia test for our DNB students. It was designed to test their depth of understanding of fundamental concepts of anaesthesia for neurosurgery. By the way, Chintan, the topper got a prize from our HOD, Dr. Muralidhar.

If you want the answer key to this quiz, you will have to leave a comment.

NEUROANAESTHESIA QUIZ

Answer all questions. There is no negative marking. MCQs can have more than one correct answer and all the answer should be correct to get a mark.

Time: 45 mins

  Brain represents ___ % of body weight and receives about ____ % of cardiac output. Oxygen consumption of brain is about ___ ml/ 100 gms of brain tissue per minute, so total brain oxygen consumption constitutes about ____ % of total body oxygen utilization.

3. Normal ICP is __________

4. What can you understand by the illustration shown below


5. Two components of cerebral metabolic activity are

6. CMR decreases by _____ per °C of temperature reduction

7. Why isn’t it a good idea to rapidly normalize PaCO2 in a patient who has had a prolonged period of hyperventilation?

8. What do these different waveforms represent?(Name the different waveforms)



9. Main energy substrate used for energy production is ________

10. What is inverse steal phenomenon?

11. Complete the following table which shows the effects of anesthetics on CBF and CMRO2( Increase = ‘+’ , decrease = ‘–‘ and No change = '0' )

CBF

CMRO2

Halothane

Isoflurane

Sevoflurane

Propofol

Thiopentone

Midazolam

Fentanyl

N20 with IV agents

12. “Pulsatality index” is measured by which monitoring modality _____________

13. What do you know about Near Infrared Spectroscopy?

14. Rationale of using beta blockers as premedication in neuroanaesthesia ____________

15. The following monitoring techniques are used to detect venous air embolism. Arrange them in decreasing order of sensitivity

a. Pulmonary artery catheter

b. ETCO2

c. TEE

d. Precordial Doppler

e. Mass spectrometry of ETN2

16. During preanaesthetic evaluation of a head injury patient you notice that he has flexion withdrawal response and is making some incomprehensible sounds. He doesn’t open his eyes even on painful stimulus. What is his GCS score?

17. Methods to control intracranial hypertension (at least four).

18. All the following are true about GABA except

a. GABA is inhibitory neurotransmitter

b. There are two major types of GABA receptors- GABAA and GABAB

c. GABAA acts by opening chloride channels and GABAB acts by opening potassium channels

d. Barbiturates and Benzodiazepines act by enhancing action at GABAB

19. All are true about cerebral autoregulation except

a. It occurs between 50-150 mm Hg

b. It is a Myogenic response

c. Occurs immediately after the pressure change

d. Range of autoregulation is shifted to a higher pressure in hypertensives

e. Abolished by trauma, hypoxia, and inhalational anesthetics

20. All the following are true about CSF except

a. It is formed at a rate of 0.3-0.4ml /min allowing complete replacement 3-4 times a day

b. One of the three major components that occupy the space in skull, with other two being brain(neurons and glia) and Blood perfusing the brain

c. Furosemide and acetazolamide doesn’t decrease CSF production

d. Formed by choroid plexus epithelial cells

e. Has a higher protein concentration than serum

21. When the brain is stiff (low compliance) and enlarged, ICP

a. rises only minimally when the patient coughs

b. rises significantly with a small increase in arterial CO2

c. is unaffected by arterial desaturation (hypoxia)

d. falls if the patient is put in the head-down position

e. rises if the head is twisted to the left or right

22. Cerebral perfusion pressure (CPP)

i. is satisfactory if more than 70 mmHg in a patient with a head injury

ii. is calculated by adding mean arterial pressure (MAP) and ICP

iii. falls if arterial BP falls following induction of anaesthesia

iv. can be calculated by “guessing” ICP to be 20 mmHg after a head injury causing 5 min unconsciousness

b. when low should be treated by infusing dextrose-saline solution

23. All the following processes protect against ischemic damage of brain except,

a. Maintaining normal blood flow

b. Reducing metabolic rate, thereby maintaining ATP levels

c. Scavenging free radicals

d. Increasing intracellular concentration of sodium and calcium

e. Facilitating release of excitatory amino acids

24. Following a severe head injury, ICP will rise to damaging levels if

a. the patient develops airway obstruction

b. the patient becomes severely hypertensive

c. the patient is allowed to breathe halothane spontaneously during an anaesthetic

d. arterial hypoxemia occurs

e. the patient suffers severe pain from other injuries which is not treated

25. All the following are true with respect to focal ischemia of brain tissue except.

a. There are three regions in the ischemic zone

b. “Penumbra” is a region of normal blood flow

c. Inverse steal is beneficial in focal ischemia of brain tissue

d. Apoptosis occurs at less compromised region of ischemia and necrosis occurs at the core of ischemic area

26. All the following are true about effects of inhalational anesthetics on CBF except

a. Isoflurane and sevoflurane are the ideal volatile anesthetics for neurosurgery

b. Desflurane is recommended for space occupying lesions

c. Induction doses of sevoflurane( 1.5-2 MAC) causes epileptiform seizures in some patients

d. Volatile agents abolish PCO2 reactivity of CBF

27. Concerning intravenous agents

a. ketamine has no effect on ICP

b. thiopentone reduces ICP by direct cerebral vasoconstriction

c. a moderate fall in arterial BP following thiopentone in a patient with cerebral decompensation (raised ICP) need not be treated immediately

d. propofol does not effect cerebral metabolic rate

e. the patient will recover rapidly when anaesthesia has been maintained by a thiopentone infusion

28. EEG

a. Generated by pyramidal cells of granular cortex

b. Deep sleep and deep anaesthesia produce delta waves

c. Theta waves are high frequency, low amplitude waves seen in awake adults

d. Indicated intraoperatively in detection of cerebral ischemia, assessment of pharmacologic interventions(burst suppression) and brain death, diagnosis and management of intractable epilepsy

e. Plot of voltage against time

f. Frequency increased by high dose of intravenous agents like thiopentone, propofol, BZDs and etomidate

29. All the following are true about Sensory evoked potentials except,

a. There are three modalities – SSEPs, BAEPs, VEPs

b. Individual peaks are described in terms of amplitude, latency and polarity

c. For SSEP – 50% reduction in amplitude is clinically significant

d. Evoked potential of brainstem origin are more vulnerable anesthetic influence when compared to those of cortical origin

e. VEPs arise from the brain stem

f. Volatile agents cause dose dependent increase in latency and decrease in amplitude of cortical evoked potentials

30. Mannitol

a. Given IV in the dose of 0.25 – 1 gm/kg; action begins within 10-12 minutes and lasts for 2 hours

b. Larger doses produce longer duration of action

c. Is effective only when BBB is intact

d. Should be given rapidly for it to attain its peak onset of action early

e. Can cause a rebound increase of ICP

f. Prolonged use of mannitol may produce dehydration, electrolyte disturbances, hyperosmolality, and impaired renal function

31. About jugular bulb venous oximetry all are true except,

a. Estimates balance between cerebral oxygen demand and supply

b. Normal SjVO2 is 60-70%

c. Changes in oxygenation of systemic blood influences SjVO2

d. SjVO2 increases to >75% during ischemic injury

e. It doesn’t detect focal ischemia

32. Wakeup test

a. Commonly used in scoliosis surgery to identify reversible damage to CNS by spinal distraction

b. Patient is woken up after complete reversal of muscle relaxation

c. Patient “awareness” is one of the adverse effects of the test

d. TIVA is the anesthetic technique of choice

33. In semi sitting position all are true except

a. Reduced venous return to the heart

b. Increased chances of venous air embolism due to sub atmospheric pressures in cerebral veins and dural sinuses

c. Pressure transducer should be kept at the level of external auditory meatus

d. Spontaneous ventilation is better than controlled, since the latter further reduces the venous return

e. Provides very good access to posterior fossa tumors

34. White matter receives more blood than grey matter, since it plays a crucial role in the normal functioning of grey matter – T / F

35. Optimum burst suppression is obtained more commonly by thiopentone when compared to other anaesthetic agents. T / F

36. Cerebral oxygen consumption decreases above 420 C. T/ F and why?

37. The magnitude of CBF reduction with Hypocapnia is greater during volatile anaesthetic. T / F and why?

38. Resting membrane potential of a neuron is nearer to the equilibrium potential of sodium. T/F

39. Children have higher CMRO2 than adults. T/F

40. Muscle relaxant can be given in just adequate doses while monitoring cranial nerves. T/F

41. Mill wheel murmur is one of the very useful early signs of venous air embolism. T/F

46 comments:

ajey said...

very interesting and stimulating questions, thank you sir.

sumit said...

a thorugh coverage of neuroanesthesia

Jim's Blog said...

Excellent questions. Thanks

Jim's Blog said...

May I have the answer sheet?

Ira said...

great idea and quiz. i would like to check my answers. thanks

mido said...
This comment has been removed by the author.
mido said...

this is a very great work. it intended to fire the brain thanks alot.

jairojerez said...

Excellent quiz. We nned the aswer key for our group, please.
Very grateful,
-Jairo

jairojerez said...

Excellent quiz.
Please send answer key for our group.
Very grateful,
-Jairo

jairojerez said...

please the anwer key
thanks

Abdel Nour said...

thanks, please send me answer key

hussein said...

thank you for the questions

Wangui said...

Really helped consolidate what i'd been reading!! Thanks

Jason said...

thanks for the quiz

Jason said...

where are the answers to the quiz?

Shaktiman said...

Nice post.
Utah Plastic Surgery Bountiful Ut

amandeep said...

it is thourgh coverage of subject

Dr Shankar said...

Its nice work you have touched almost all the areas of NA

Excellent
now forward the answer sheet for the same

domingo895 said...

Can I have the answers to the neuroanesthesia quiz sir?

Dr Ali Raja said...

dear anil,
i thoroughly enjoyed solving this quiz. sir will you please provide me answer key so that i can evaluate myself.
ALI raja

akka said...

Thorough job covering many aspects of neuroanesthesia.

akka said...

thorough job

akka said...

good job

akka said...

good job

akka said...

good job

transientforlife said...

awesome, please email me answers

dr.hosam5000 said...

Excelent questions very comprehensive cover allthe topic thanks

dr.hosam5000 said...

May l have fhe answer sheet please

Liz M said...

Awesome and thorough questions. Please send me an answer key so I can evaluate myself. Thanks for the wonderful blog you've created.

Anesthesia01 said...

This will be very helpful for my upcoming Nuero exam. Would love to check my knowledge. Thanks for posting.

aasam said...

A very healthy exercise after reviewing the neuroanesthesia to know, how much you gain....
Really a great effort

5b8e1fd4-5330-11e3-99a7-000bcdca4d7a said...

detailed

5b8e1fd4-5330-11e3-99a7-000bcdca4d7a said...

detailed

5b8e1fd4-5330-11e3-99a7-000bcdca4d7a said...

detailed

5b8e1fd4-5330-11e3-99a7-000bcdca4d7a said...

detailed

Nareg Gharibjanian said...
This comment has been removed by the author.
Mohd kangoo said...

Excellent attempt to to check our knowledge of Neuroanesthesia

dr.sudhanshu said...

may i have the answer sheet?? its very nice test sir

bornloser said...

Interesting and stimulating question.Would wish to check my scores.Please send me the answer key.

manish said...

very interesting and basic questions

manish said...

interesting

manish said...

interesting

manish said...

it was really very interesting knowledgeble

manish said...

may i have the answer sheet ??

Billy Bob said...

I would like to check my answers please

Suma Ahmad said...

conceptual questions. Thank you... May I have the answers..