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33 Cards in this Set
- Front
- Back
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15A-10 Factors that increase coronary blood flow:A - hypoxia B - aortic systolic blood pressure C - hyperthyroidism D - aortic compliance
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Answer: AMyocardial oxygen consumption is the most important determinant of coronary blood flow.
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15A-11Cardiogenic shock is caused by:A - ArrhythmiaB - Decreased stroke volumeC - Decreased arteriolar pressureD - Decreased venous pressure
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Answer: B
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15A-29Haemoglobin structure isA. Two porphyrin rings with 2 Fe3+ ionsB. Four porphyrin rings with 4x Fe3+ ionsC. Two porphyrin rings qith 2x Fe 2+ ionsD. Four porphyrin rings with 4x Fe2+ ionsE. Two porphyrin rings with 4 x Fe 2+ ions
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Answer: DKam 3rd edition page 271 Protoporphyrin combines with iron in the ferrous state (Fe++) to form haem. Each haem combines with a globin chainAn Hb molecule is formed by a tetrameter of four globin chains, each with its own haem group in a hydrophobic pocket
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15A-37. Cerebral blood flowA: Indirectly proportional to glucoseB: Increases with neuronal activityC: Equals mean arterial pressure minus intracranial pressureD: Equals 30% of cardiac outputE: Increases with increased age
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Answer: B, CBF:A&B: regional cortical blood flow is associated with regional neural activity (flow/metabolic coupling), glucose uptake also corresponds with regional neuronal activityC: CPP=MAP-ICP, CBF=CPP/ResistanceD:15% cardiac output - 50-65mL/min per 100 g of brain, 750-900ml/min, 1400g brain - 2% body weight.E: decrease with age (internet reference)Reference Berne p243 Kam p50
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15A-73Amiodarone: A. Half life 24-36 hrs B. act on cardiac K+ channels C. Doesn't cause hypotension when given IV D. ?
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Answer is BAmiodarone:A: elimination half life 4 hours to 52 daysB: blocks K+ ion channels, Na Channel, beta blockade, and calcium channel blockade.C: oral - nil effect on BP, Intravenous - decrease LV contractilitySmith-Scarth-SasadaGoodman & GillmanStoelting
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15A-74: Adenosine and amiodarone: A. Both class 3 anti-arrythmics B. both cause bronchospasm & tachycardia C. Half life 10 secs & 10 hrs respectively D. Slow AV conduction & prolong pr interval E. Both used for treatment of svt & vt
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Answer DA: Amiodarone is class 3, but Adenosine is class 5 of Singh Vaughan Williams classificationB: Adenosine can cause bronhcospasm, amiodarone not known to cause thisC: plasma half life of adenosine is <10s, amiodarone hours to months.D: Adenosine transiently slows sinus rate and AV nodal conduction velocity and increases AV nodal refractoriness. Amiodarone prolong action potential and decrease conduction velocity.E: amiodarone works for SVT and VT, but Adenosine only work for SVT.
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15A-75Ceasing metoprolol preoperatively can cause: A. myocardial ischaemia B. bradycardia C. premature labour D. hypoglycaemia E. bronchospasm
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Answer: AUpregulation of β-adrenergic receptors occurs with chronic administration of β-adrenergic antagonists such that abrupt discontinuation of treatment may lead to supraventricular tachycardia that is particularly undesirable in patients with coronary artery disease. Slowly tapering the dose of β-adrenergic antagonist will prevent withdrawal responses.B: opposit is trueC:not premature labour, but low birthweight, nenatal bradycardia and hypoglycemia with beta blockers, and major defect if used in 1st trimester.D: causes hypoglycemia, ceasing it would probably cause the oppositeE: can cause bronchospasm, ceasing it would cause the opposite
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15A-76Esmolol: A. metabolized by plasma esteraseB. long effect timeC. more lipid soluble than propranololD. onset of peak eff
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Answer: A is trueB: After a typical initial dose of 0.5 mg/kg IV over about 60 seconds, the full therapeutic effect is evident within 5 minutes, and its action ceases within 10 to 30 minutes after administration is discontinued.C: false, esmolol poor lipid solubility limit transfer to CNS and placenta, propranolol readily crosses tge BBB.D: 5mins
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15A-79 Which drug is contraindicated in Pre eclampsia A Methyldopa B Labetalol C Hydralazine D Perindopril E Clonidine
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Answer:DA: being used as outpatient management during pregnancyB: Intravenous useC: Intravenous useD: ACE & ARB tetratogenic in first trimester, renal, oligohydramnios, skull hypoplasia in second and third trimesters.E: currently in use
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15A-80 Adminstration of clonidine can cause A. Tachycardia B. ? C. Transient Hypertension D Seizures E. Delirium
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Answer: CA: false, slow HR and marked bradycardia, stimulates parasympathetic outflowB:?C: TrueD:probably not as cause sedationE: false, sedative used to treat delirium
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15A-85 Regarding adverse/side effects of Clonidine A: Hypotensive side effect is exacerbated by tricyclic antidepressants (TCAs) B: Tachycardia C: Excess salivation D: Sudden cessation causes hypertensive crisisE. ?
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Answer: DA:TCA inhibit the antihypertensive effects clonidine by blockade of noradrenaline reuptake.B:false, slow HR and marked bradycardia, stimulates parasympathetic outflowC: false, cause dry mouth in 50% of patientsD: true
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15A-86Spironolactone:A: K sparing effect by potentiating/agonisim of aldosterone/receptorsB: PO, its theraputic effect is complete in/by 24 hoursC: K sparing effect agonised?/antagonised by NSAIDsD: Causes increased K movement across luminal membraneE: Risk of HYPERkalaemia with B blockers
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Answer: CA: fALSE, competitive antagonist of aldosterone in the DCT, inhibiting Na reabsorption and increasing K+ resabsorption, promoting saliureis, and potentiating that produced by other diureticsB: FALSE, slow onset of action, diuretic effects takes 3 - 4 days to establishC: possible. NSAID can reduce the diuretic, natriuretic, and antihypertensive effect of loop, potassium-sparing and thiazide diuretics. Combination with NSAIDs, has been associated with severe hyperkalemia.D: false, supposed to potassium sparingE: dont think so, often used together
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15A-97 Which of these drugs crosses the blood brain barrier? ( repeat) A. Propranolol B. HeparinC. suxmethoniumD. EdrophoniumE. Dopamine
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Answer: A
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15A-x8 Avoiding ACE-I in pregnant because:A. serious foetal malformations if taken during 2nd and 3rd trimesterB. foetus unlikely to be harmed if taken during first trimesterC. should be avoided completely in pregnancyD. All of the aboveThis is a made up question as the blank bank did not give any choices.
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Answer: D ACEI & ARB: tetratogenic in first trimester, renal failure, oligohydramnios, skull hypoplasia in second and third trimesters. One article suggest ok to use in first trimester but safety not guaranteed.Another article found major congenital malformations ASD, PDA, hydrocephalus and spina bifida even during use in first trimester only,But better alternative antihypertensives, so should be avoided.
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15A-22 Na/K ATPase A. Is electrogenic B. Is impaired by low extracellular ECF conc C. 3 ATP used for each 3 na pumped D. 3 K+ in for 2 Na+ out
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Answer: AA: 3 Na+ out, 2 K+ in, leaving net deficit of positive ions inside causing negative potential insideB: Not really, Na+K+ATPase can run in reverse, if Na and K electrochemical gradients can be increased to degree that the energy stored in their gradients is greater than chemical energy for ATP hydrolysis, these ions can move down that gradient, the pump can synthesize ATP from ADP and phosphate, it can donate and produce ATP or use ATP to change its conformation to pump Na out and K in. Relative conce of ATP, ADP, and phosphate and electrochemical gradient for Na and K determine direction of enzyme actionC: The pump is energy dependent, one ATP molecule is split for every three sodium ions extruded, not 3 ATPD: 3 Na+ out, 2 K+ in
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15A-23 Nernst potential: A: electrical neutrality existsB: chemical equilibrium across membrane C: potential at which there is no net movement of ions.D: at which na out? Is greater than na in E: at which cl/ca? In? Is greater than out
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Answer:CNernst potential is the maximum electomotive force that can be generated by a given ratio of concentrations of an ion, or that the maximum ratio of concentration that can be sustained by a potential difference imposed from an external force, The diffusion potential across a membrane that exactly opposes the net diffusion of a particular ion through the membrane is called the Nernst potential for that ion, determined by ratio of concentration of that specific ion on the two sides of the membrane, greater ratio, greater the tendency for diffusion in one direction and the Nernst potential required to prevent additional net diffusion is greater. Nernst equation: z= valence, R =gas constant, T = absolute temperature, F=Faraday constant.2nd equation 61/z because, R and F are constants, and body temp is 37C =310kelvin. R=8.3, temp 37celsius =310K, F=9.6x10
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15A-24 Best way to measure breath by breath oxygen A Paramagnetic analyser B. Fuel Cell C. Clarke Electrode D. Sniff test E. Hot wire anemometerF: Infrared absorptionG: mass spectroscopy
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Answer: AParamagnetic oxygen analysis – most commonly used in breath to breath analysis in anaesthetic breathing circuits. When introduced into a magnetic field, some substance locate themselves in the strongest portion of that field, ie paramagnetic. Oxygen is the only important paramagnetic substance in anaesthesia, when gas containing oxygen is passed through a switched magnetic field, gas expand and contract, causing pressure wave that is proportional to oxygen partial pressure, reference and sample gas are are joined by a differential pressure or flow sensor, the difference detected is converted to electrical signal that is displayed as partial pressure or volumes percent. Short rise time allow both inspired and end tidal to be measured even at high resp rates.Infrared – most often used to measure CO2, nitrous oxide, and volatile agents, atoms with >2 dissimilar atoms have unique IR absortion spectra. Amount IR absorbed is proportional to conc, determined by comparing the IR absorbance of a known reference sample. Non-polar molecules argon, nitrogen, oxygen, helium, xenon can not be measured. Tend to underestimate inspired level and overestimate end tidal values at high Resp rates. Clarke electrode / fuel cell : electrochemical oxygen analyzer consists of a sensor, which is exposed to the gas being analyzed, and the analyzer box, which contains the electronic circuitry,display, and alarms. The sensor contains a cathode and an anode surrounded by electrolyte. gel is held in place by a membrane that is nonpermeable to ions, proteins, and other such materials but is permeable to oxygen. membrane should not be touched, because dirt and grease reduce its usable area. In most cases, the sensor is placed in the inspiratory limb of the breathing system. Most of these analyzers respond slowly to changes in oxygen pressure, so they cannot be used to measure end-tidal concentrations. Some newer monitors can analyse oxygen quickly enough to measure inspired and exhaled concentrations. Life of sensor is measured in percent hours, higher conc exposure shofter the sensor life. Daily calibration, expose to air when not in use to prolong life spectrophotometry : shining radiation thru sample, wavelength absorbed relates to type of gas and amount is proportional to concentration : principle of the pulse oximeter (oxy < deoxy at 660 nm and more at 940 nm)
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15A-30 The FRC in a child is: A. 20ml/kg B. 30ml/kg C. 40ml/kg D. 50ml/kg
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Answer: B
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15A-57 Regarding peripheral chemoreceptors: A. their blood flow is 3x their metabolic rate B. Something about response rate C. Type 1 fibres are in contact with glossopharyngeal nerve D. Type 2 fibres are ..?.. E. Aortic body is responsible for most respiratory responses
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Answer: CA: 10x metabolic rateB: Fast response rate, lung-to-carotid body circulation time (about 6 s), most reponse in 5 - 10mins, plateau in 20-30mins, Nunn page 72, biphsic response - over hours, plateau up to 24 hours. , if altitude response up to 2-3 days.C: Type 1 glomus cells are in synaptic contact with nerve endings of the glossopharyngeal nerveD: ?Type 2 glomus cells function as stem cells?E: Carotid body is responsible for respiratory responses and aortic body for CVS responses
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15A-64. Peripheral chemoreceptors: A. Respond to decreased O2 saturation B. Respond to increased arterial pH C. Respond to decreased arterial CO2 tension D. Nonlinear increase with arterial oxygen tension E. Slow response to changes in arterial carbon dioxide tension
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Answer: DA: false. respond to decreased pO2B:false. stimulated by increase H+ therefore decreased pHC: false, stimulated by increased CO2 tensionD: true. PO2/ventilation curve is in the shape of rectangular hyperbole. E: false, Fast response, within seconds
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15A-58 Severe hypercapnia is most likely to be associated with... A. Increased catecholamines B. Increased urine output C. Increased myocardial contractility D. shift O2Hgb dissociation curve to the leftE. Reduce systemic BP
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Answer: AB: high PCO2 constriction of afferent arteriolesC: direct depressant effects on myocardium, except opposed by rise of catecholamine releaseD: false, right shift.E: false
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15A-59 In which form is the majority of CO2 carried in blood? A. Carbamino groups bound to proteins B. Carbamino groups bound to haemoglobin C. Dissolved in plasma D. Bicarbonate in red blood cells E. Bicarbonate in plasma
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Answer:EHCO3- - largest fraction 13.42mmol/L in plasma, and 5.88mmol/L in RBC.see page 160 table 10.2 in Nunn
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15A-60Which respiratory parameter cannot be obtained using spirometry? A. Tidal volume B. Vital capacity C. Inspiratory capacity D. Residual volume E. Expiratory reserve capacity
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Answer:D
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15A-61 In IPPV and PEEP, what changes would you expect: A. Change in a systolic parameter B. Change in a diastolic parameter C. On echocardiography you would notice a left shift in inter ventricular septum D. a few other wrong answers...
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Answer:increase in mean intra-thoracic pressure, as seen during positive pressure ventilation, impairs venous return, increases pulmonary vascular resistance and so reduces cardiac output
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62. 15A-62PEEP leads to A. variable effect on FRCB. reduced lung complianceC. reduce lung waterD. reduce airway resistanceE. No effect on lung compliance
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Answer: DA: increase FRCB. increase compliance in dependent lung and reduce compliance in non-dependent lungC: redistributes lung waterD: trueE:
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63. 15A-63 Mixed venous PO2 would be due to: A. West Zone 3 B. oxygen consumptionC. Hgb concentrationD. cardiac outputmade up question as no choice in black bank
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Answer: in my humble opinion, all are components of the below fick equation, and therefore all are possible answers.Fick's equationO2 consumption = Q x Hgb x (SaO2 - SvO2)
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65. CM44 Turbulent flow is LESS likely with A. Decreased viscosity B. Increased temperature C. Reynold number > 2000 D. Bifurcation E. Increased radius
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Answer: B (by elimination)Re = density x velocity x Diameter / viscositytemp reduce densityviscosity of liquid decrease with increase temp (breaks cohesive forces between liquids)viscosity of gas increase with increasing temp(increases molecular interchange as gas move faster at higher temp)
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66. 15A-66 Regarding muscles of respiration A: Diaphragm moves 1 cm in normal breathingB: Diaphragm can be an accessory muscle of expiration C: Internal intercostal muscles are inspiratoryD: 50% of normal breathing is due to intercostalsE: SCM is an accessory muscle of inspiration that acts by raising the first rib
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Answer: AA: diaphragm moves 1cm in normal breathingB: false, diarrphragm not used in expirationC: internal are expiratoryD: intercostals do very little during quiet breathingE: elevates sternum, nil attachments to the ribs.
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70. RE82 Airway Resistance: A: Decreases with decreasing viscosity B: Increases with increasing lung volume C: The pressure between the alveoli and mouth divided by flow (?exact wording) D: E: Mediated by α receptors
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Answer: CA:Resistance = 8nL / TT r4 if laminar flow, but airway mostly transitional flowB: falseC: trueD:E:Beta 2
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15A-142 The following are complications of oxygen therapy EXCEPT:
A. CO2 narcosis
B. seizures with partial pressures administered over 1,000 mmHg C. haemorrhagic pulmonary interstitial oedema
D. fibrolental hypoplasia
E absorption atelectasis
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Answer: BA:trueB: above 3 ATMC: maybe trueD: TrueE: True
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15A-145 Bronchial artery supplies: A. Provide a low pressure flow to lung parenchyma B. Provide blood to all bronchioles down to the respiratory bronchioles C. Are branches from the intercostal arteriesD. Provides blood supply to both visceral and parietal pleura E. Provides supply to some lung parenchyma
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Answer: BA:false: arise from aorta so will be high pressure flowB: true, supply as far as small bronchioles, disappear as soon as alveoli appearC:possible, variable in number and origin especially right side, aorta, intercostals, internal mammary, right subclavian, of common trunk off aortaD: false parietal supplied by intercostals, visceral is bronchialE: true - but not just some but all parenchyma except alveoli
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15A-x12 Arterial blood gas:pH 7.54 pCO2 27 HCO3 22Which ONE of the following explains these ABG results: A: Altitude for several weeks B: Hyperventilation for 5 minutes C: DKA D: Prolonged vomiting E: ?
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Answer: sorry not sure yet
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15A-x17 Peripheral chemoreceptors respond to: A: pH B: pO2 C: pCO2D: all of the above
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Answer:D
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