Tests_B

Question 1

Write correct neurotransmitter

1. Pre-ganglionic neurotransmitter for para$ and $
2. Postganglionic for $
3. Postganglionic for para$

Answer 1

1. Ach
2. NA
3. Ach

Question 2

Describe the changes in the resp system that take place in the elderly?
Lung elasticity
Elastic recoil
Vital capacity and residuel lung volume

Answer 2

Derc. Lung elasticity:
Incr. in compliance
Total pulm compliance remains the same due to
Fibrocalcification of the thoracic cage - leading
To reduced compliance of chest wall

Loses elastic recoil, this leads to early a/w closure during expiration
Thus closing volume will begin to exceed FRC: (65 yrs)
Lower V/Q ratios. And lower arterial O2 tension

Vital capacity: progressive erosion
Residual Lung volume: increase

Question 3

Why is it prefered to admin GA to an obese pt with the aid of a ETT and controled ventilation? Only if a/ w can be safely established + need rapid seq induction.

Actually regional is prefered but spinal / epidural doses need to be 75-80% the normal dose.

Answer 3

Lung chest compliance is decreased: (35%)
- decr size of thorax, due to big abdomen -
diaphram splitting
- heavy chest wall
- all lead to incr in work of breathing

Decrease in FRC (normaly dcr in obesity)

• lowered lung chest compliance further incr. work of breathing
• decr in arterial oxygenation - low VQ units
• effective mx of a/w and preox very NB due to pt becoming hypoxic early due to incr. oxy demand
• effect of IAA

OSA more common in obese pts. ( obstructive slaap apnoea)
Sedative and anelgesic drugs may compromise
A/w - they need to sleep on added oxy in hosp.

Question 4

Review textbook p.149

62 year old man weighs 80 kgs
He must undergo a hemicolectomy that will last 3 hours.
He is NPO since 22h00 and the procedure is scheduled for 8h00.
He had bowel prep.
Expected bloodloss is 500ml.

What is his intraoperative fluid req?

Answer 4

Preoperative
1-1.5 ml/kg/hr NPO
Normal saline= 360ml isotonic crystalloid

Maintenance: same as above

Third space loss: 
1-6ml/kg/hr= 240-640ml
Isotonic crystalloid (more because of large surg)

Blood loss:
75ml/kg x 80 = 60000ml, thus

Question 5

List 5 drugs or classes that should be avoided in asthmatic?

Answer 5

Beta blocker
NSAIDs
Aspirine
Adenosine
Atracurium, Mivacurium

Question 6

A pt with IHD must receive GA:
Which heamodynamic changes has been shown to be a specific risk?

Why?

Which drug will reduce risk of acute ischeamia?

Answer 6

Tachycardia.

During a tachy, diastolic time is decreased
Coronary flow is time dependant.
With decreased flow (stenosis)
Ischeamia and necrosis may result

Beta adrenergic receptor blockers

Question 7

Clinical symptoms and signs of Malignant Hyperthermia?

THAT TRIM

Answer 7

Non specific - THAT
  Tachycardia
  HyperK
  Acidosis
  Tachypnoea

Specific - TRIM
  Temp incr
   Rhabdomyolysis
   Increased CO2 production
   Muscle rigidity

Early signs:
Masseter muscle spasm and other muscles
Tachycardia and HTN
One of the first signs if unexplained
PaCO2 incr production and
Metabolic acidosis. (Both due to incr
metabolism) and stimulate symp system.
Dysrythmia (hyperkaleamia)
Hyperthermia (exceed 43)
Hypercapnoea and tachypnoea

Late
   Warm to touch
   Cyanosis
   Metabolic acidosis - incr
   Peaked t waves - hyperkaleamia
   Darker blood

Question 8

What is the drug of choice for MH?

Answer 8

Dantroline sodium

Question 9

Why will elderly pts require reduced dosages of the following drugs?

Propofol
Opioid

Answer 9

Propofol:
Hepatic function declined, decr in clearance
And prolonged duration of action

Opioid:
Slow arm- brain circulation - give slowly
Longer half life and are more sensitive to effects

Question 10

Morphine:

1. Optimal route for morphine?
2. Why would you use this route?
3. What dose would you use for this route?
4. What end point would be used to know when to stop admin the initial dose?

Answer 10

1. IV
2. Rapid onset of effect
3. 1-2mg increments IVI every 5 min
   OR 0.15mg/kg imi
4. Tolerance to pain

Question 11

What are the sfx of morphine?

Answer 11

GIT : NVC

Drowsiness, sedation
Resp depression
CVS - hypoT

Question 12

Name an alternative technique to achieve anelgesia other that IV morphine?

Answer 12

Patient controlled anelgesia (PCA)
Epidural
Femoral nerve block
Ketamine low dose

Question 13

List the problems you can anticipate during an anesthetic for post-tonsillectomy bleeding?

Answer 13

Hypovoleamia
Aneamia
Swallowed blood and full stomach
Oedema of a/w structures
Lack of cooperation for LLposition
  RSI with cricoid pressure alternative
Hypothermia. (Because of fluid rescuss)

Question 14

Explain the concept of central venous pressure and how it is measured?

Answer 14

Used to:
Measure Right heart function
And intravascular blood volume

How it works:
Uses a manometer filled with IV fluid
Attached to central venous catheter
Placed into SVC (neck veins, arm, groin)

Electronic transducer may give continues CVP and waveforms.

Question 15

What is measure by a capnograph and what is the importance of it in GA?

Answer 15

Measure End tidal CO2

Monitoring intubation (correct placement)
Bronchospasm, rebreathing and circulatory collapse can be dx.  NB

Question 16

T/ F:

1. Ethanol is used as an antidote to bothe methanol and ethelyne glycol poisoning.
2. Toxic dose of salicylates are known to cause resp depression.
3. Oral acetylcysteine is effective in the Rx of paracetemol poisoning.
4. Major toxic effect of organophosphate poisoning is due to stimulation of the nicotinic cholinergic receptors.
5. Effects of cocaine is due to direct stimulation of adrenergic receptors.
6. Ketamine, a dissociative anesthetic agent, has similar effects to that of phynocyclidine (angel dust)
7. Ecstasy (MDMA) is a hallucinogenic amphetamine.
8. Methylamphetamine is also known as TIK
9. Overdose with phenothiazine like agent cause EPSE.
10. Resp failure is the most common death is scorpionism
11. The toxic venom of cape cobra venom causes a curare like effect.
12. Paracetamol is primarily a nephrotoxic agent in overdose.

Answer 16

1.
2.
3. False
4. True
5. 
6.
7. True
8. True
9. 
10. True
11.
12. False

Question 17

What is absorbtion atelectasis?

Answer 17

By raising O2 content in alveolus the Hb molecules now have sufficient oxygen.

BUT nitrogen is being lost (normally 80% of normal alveolar volume)

Nitrogen is insoluble and remains in alveolus once oxygen removed, thus acting as structure to keep alveolus open.

By filling lung with 100% oxygen you remove nitrogen and as oxygen is removed the alveolus becomes “pap” - decreasing volume.

This aggrevates VQ pathology

Question 18

List chieve toxic effects/ mechanism of:

1. Cape cobra
2. Boomslang
3. Puff adder
4. Button/ widow spider
5. Parabuthus scorpion

Answer 18

1. Neurotoxic - post synaptic adrenergic receptor
2. Heamtotoxic - prothrombin and facto X affected
   Bleeding
4. Neurotoxic - presynaptic peripheral nerve
   endings, massive neurotransmitter release
5. Neurotoxic - Na channel depolarizor

Question 19

Define osmolality?

What is the osmolality of the folowing pt:

Formula

Answer 19

Measure of the osmoles of a solute per kg solvent.

2Na + urea+ glucose

Question 20

What is a third space loss? Review

At what rate must it be replaced?

Answer 20

Fluid loss due to oedoema or transcellulR fluid displacement. Thus cannot enter vascular compartment due to high Na content in injured area.

1-6ml/kg/hr

Question 21

Name factors that can cause generalized tissue oedema?

Answer 21

Oncotic pressure decr. (Albumin)
Hydrostatic pressure increase. (HyperT)
Increase in permeability of membrane
Capp endothelial damage. (Inflammation)

Question 22

T/F:
1. Sellicks manouvre is posterior pressure on the thyroid cartilage during the process of RSI, to prevent regurgitation in a pt with a full stomach.

2. Inheritance of abnormal enz which is responsible for syx apnoea is autosomal dominant?
3. ETT with internal diameter of 6.5mm would be correct for a 6yr
4. A morbidly obese pt is not in danger of aspiration of stomach content, provided he/she has not taken anything orally for atleast 6 hours.
5. Normal neonate will become hypoxic more rapidly after onset of apnoea than a normal adult.

Answer 22

1. False - cricoid pressure
2. True
3. False (age /4 + 4)
4. False
5. True

Question 23

What is the commonest blood gas abnormality seen ass with inadequate FgF when using a non- CO2 absorbant circuit?

Answer 23

Hypercapnia

Question 24

Name 3 groups of effector organs predominantly influenced by the ANS?

Which 2 substances produced by adrenal medulla - name the one which is secreted in highest quantity in adult first

Answer 24

Heart, smooth muscle and glands

Adrenalin
Noradrenaline

Question 25

Review breathing patterns.

Answer 25

Spontaneous IPPV IPPV and PEEP CPAP

Question 26

Explain how ill-considered ventilation can cause pneumathoracis (baro or volume trauma)?

Answer 26

Alveoli exhibit interdependance - pressure is distributed amongst them (they dont burts due to pressure) Rupture of alveoli into the bronchovascular bundle - leads to interstitial oedoema, not the pleura.

Question 27

Complications of alveoli rupture into bronchovascular sheath?

Answer 27

``` Interstitual emphysema Pneumothorax Pneumopericardium Pneumomediastinum Subcut emphysema ```

Question 28

What are the CI to thiopentane?

Answer 28

Porphyria CVS (tachycardia undesired -IHD and HTN) Asthma

Question 29

List 3 local blocks where adrenaline is CI?

Answer 29

Penis, tip of nose Biers block Unstable angina pectoris Uncontroled HTN

Question 30

5 advantages of effective pain mx?

Answer 30

``` Reduces suffering Resp - increase wall compliance CVS - oxygen comsumption less Coagulation (less adverse events) Immunity improved Prevent chronic pain Saves money ```

Question 31

What are the 3 components of blanced anesthesia?

Answer 31

Anesthesia - Hypnosis Anelgesia. - pain relief muscle relaxation - curarization

Question 32

Name structure that needle transverses during a lumbar puncture, to aspirate CSF?

Answer 32

``` Skin Subcut tissue Supraspinous ligament Interspinous ligament Ligamentum flavum Epidural space Dura mater Arachnoid mater ```

Question 33

What is the importance of the ligamentum flavum during placement of the local anesthetic into the epidural space?

Answer 33

Epidural space is identified by the needle passage through an area of high resistance (ligamentum flavum) into th low- resistance epidural space.

Question 34

What effect will hypoxia have on the heart rate of the neonate?

Answer 34

Bradycardia

Question 35

Describe the pathophysiology of the aspiration of acidic stomach contents?

Answer 35

Aspirated fluid or acid spreads to the lung periphery within seconds (lavage does not help) Surfactant loss leads to decr. In compliance Inflammation leads to endothelial damage and incr. alveolar permeability Fluid filled alveoli - leading to Hypoxia Pulmonary oedema Stiff lungs

Question 36

What is diffusion hypoxia?

Answer 36

Same mechanism as aspiration

Question 37

T/F: 1. ET intubation is prefered during CPR. 2. During effective CPR, CO is normal. 3. Open cardiac massage is better that external cardiac. 4. During VF intial defib is at 5Joules/ kg 5. Capnograph reflects CO 6 . Capnograph reflects lung bloodflow. 7. Atropine is given in asystole 8. Bloodflow during CPR is the result of compression of heart bw the sternum an vertebrea only. 9. Ventilation of lungs and compression of chest during cardiopulmonary rescuss should not be done At the same time.

Answer 37

1. True 2. False 3. True 4. False 5. False 6. True 7. False 8. False

Question 38

List all methods you can to prevent aspiration of stomach content into lungs? 1. Prevent 2. Prevent further aspiration 3. Oxygenation 4. Remove trachebronchial material/ suction 5. Symptomatic supportive Rx

Answer 38

``` 1. Reduce stomach volume Promote stomach emptying Stomach pH>2.5 Stomach oesophagus: Barries pressure= LESP - intragastric pressure Laryngeal reflex depressed: maintain protective reflex ID at risk pt RSI ``` 2. Head down (lateral position of a/w easy t mntn) Suction pharynx RSI Intubate trachea 3. 100% o2 initially, later as needed to keep sats > 90% PEEP>= 5cm H2O to maintain alveolar volume Preventing alveolar flooding IPPV because lungs are stuff 4. Suction trachea, DONT LAVAGE Bronchoscopy if particulate matter 5. Rx: bronchospasm NO routine AB initially (only w infection) NO routine steroids ICU, clinical evaluation, CXR, blood gasses

Question 39

List safe drugs to use in PORPHYRIA 1. Induction agent 2. Muscle relaxant 3. Maintenace of anesthesia 4. Reversal of muscular relaxation 5. Intra and post op pain

Answer 39

1. Propofol 2. Succinylcoline, alcuronium 3. Sevoflurane 4. Neostigmine 5. Morphine

Question 40

Macs for. HIESDN. Review lecture 1. Halothane 2. Isoflurane 3. Enflurane 4. Seveflurane 5. Desflurane 6. n2O

Answer 40

1. 0.74 2. 1.15 3. 1.23 4. 1.85 5. 7.25 6. 101

Question 41

Define severe sepsis?

Answer 41

SIRS + proven infection + MOD

Question 42

What differentiates severe sepsis from septic shock? 4 practical points that you can use to initially improve survival in septic shock? Why is a pt in severe sepsis or septic shock at risk for resp failure?

Answer 42

The repsonse to IV fluids ``` Goal is to - maximise DO2 1. = CO x Oxygen content (Hb) 2. Requires 30% above physiological values Remove cause Support other organs - esp ventilation Steroids (only poor responders) Anti mediaters Heparin / activated protein C ``` ARDS

Question 43

``` Basic preop evaluation of a pt aimed at ID potential problems with intubation? Face Mouth Neck Thoracoabdominal abnormalities Age Gender Other ```

Answer 43

``` Face: Trauma, deformity, stridor, hoarseness, mandible Mouth Macroglossia, protruding teeth, mallampati 3and4 Neck Short and thick Decr. ROM (arthritis, disk disease, spondylitis) Fracture (subluxation) Obvious trauma Thoracoabdominal abnormalities Kyphoscoliosis Prominent chest/ large breasts Morbid obese Term/ near term pregnancy Age - bw 40-59 Gender - male Other Snoring / sleep apnoea syndrome ```

Question 44

Define the following: 1.Partial pressure of gas 2. Tension of a gas in liquid 3. Bloodgas partition coefficient of anes.gas 4. Rank order of their blood partition coef. Halothane, N2O , Isoflurane

Answer 44

1. the pressure exerted by a gas in a mixture, which is the pressure the gas would exert if it alone were in the container. 2. Partial pressure of gas that would be in equilibrium with it 3. The ratio of the amount of a substance at equilibrium which is defined in one phase compared with another - the 2 phase being of equal vol 4. Lowest to highest N2O, Isofluran, Halothane Take note that the higher MAC is the lower partitioning coef

Question 45

Name the 2 stimuli which can stimulate the ocular cardiac reflex during opthalmological surgery?

Answer 45

Pressure on the eyeball | Traction on the extraocular muscles

Question 46

What will the oculo cardiac reflex do to the pulse rate?

Answer 46

Decrease it

Question 47

Name the efferent and afferent limb of the oculo cardiac reflex? What drug is used to block this reflex?

Answer 47

Trigeminal Vagus Atropine / glycopurylate

Question 48

T/F: 1. Suxamthonium cause depolirization of the postsynaptic membrane of the NMJ. 2. Sux and ACh are both hydrolyzed by pseudocholinesterase 3. Sux is the only muscle relaxant in use that has a very short onset of action 4. Sux will cause a rise in serum K of 4-8mmol/l in a pt with kidney failure. 5. Pancuronium will cause a rise in pulse rate and BP

Answer 48

1. True 2. False 3. 4. False 5. True

Question 49

What is the clinical picture of a berg adder bite?

Answer 49

``` Local oedema Opthalmoplegia Anosmia HypoNa Resp failure ```

Question 50

``` ETT sizes for children Prem Neonate - 6mo 6mo - 1 yr 1 - 2 years Beyond 2 ```

Answer 50

3.0 3.0- 3.5 3.5-4.0 4.0-4.5 Age/4+4 Uncuffed

Question 51

Effect of CO poison?

Answer 51

OHEC left shift - thus oxygen carrying capacity Hypoxia at tissues Cytochrome enz bound - thus cannot oxidize CVS - myocardial ischeamia and vasodilation Direct effect on vascular SM = hypoT

Question 52

For CO poisoning what test will you do and what will you see?

Answer 52

Low sats at normal partial pressures of O2 | On blood gas

Question 53

On which organs will the long term effects of CO poisoning be seem? How will you mx such a pt?

Answer 53

Brain - neuro damage Heart - myocardial infarction 100% oxygen - increase dissociation of CO-Hb complex - tigh fitting mask and high flow oxygen Hyperbaric oxygen therapy : - unconscious pt - neuro/ psych features - COHb concentrations > 20% Supportive care: - cardiac monitoring - Rx of cardiac dysrythmias - correction of acidbase and electrolyte abnormalities

Question 54

Give the chemical rxn for the absorbtion of CO2 by soda lime?

Answer 54

CO2 + H2O = H2 CO3 H2CO3 + 2NaOH = Na2CO3 + 2H2O + heat Na2CO3 + Ca(OH)2 = CaCO3 + 2NaOH