2013-A Courtesy of user emrufo Flashcards

Question

[Aug12][Mar13] New: Thoracodorsal nerve arises from? A Inferior trunk B Lateral cord C dorsal scapular n D posterior cord

Answer 1

Thoracodorsal (middle subscapular) nerve arises from the posterior cord and receives innervation from C6,7,8. It innervates the Latissimus dorsi muscle. Roots->Trunks->Divisions->Cords->Branches -----------

Answer 2

B. Magnesium and A. Indomethacin even ?D. salbutamol - B>A and D? See Chestnut. Table 34-4. Cochrane review on Magnesium in preterm labour (2002) found 'no evidence of a clinically important tocolytic effect for magnesium sulphate; it did not have any substantial effect of the proportion of women delivering within 48 hours, either overall, or in any subgroup analysis. Moreover, there was no evidence of any substantial improvements in neonatal morbidity. IN CONTRAST, MgSO4 was associated with an INCREASE IN FETAL AND PAEDIATRIC DEATHS. The higher death rate was present in the SUBGROUP where the maintenance dose of MgSO4, as in the study's protocol, was high, rather than low.' Indomethacin can cause premature closure of ductus arteriosus in the fetus if given in 3rd trimester Depends on reference. NSW health policy directive states that BEFORE 34/40 there are 5 classes of tocolytic agents available in Australia currently: CCB, Beta-agonists, nitric oxide donors, prostaglandin synthetase inhibitors and magnesium sulphate. The evidence to support the use of magnesium sulphate as a first line tocolytic is poor so it is not recommended. The use of beta-agonists (like salbutamol) or multiple tocolytics is associated with a high incidence of serious adverse drug reactions. Both nitric oxide donors (like GTN) and prostaglandin synthetase inhibitors (like indomethacin) MAY HAVE A ROLE PRIOR TO 28 WEEKS.

Answer 3

A. Right upper lobe - see wiki Mar10 exam

Answer 4

D. Transtentorial herniation

Answer 5

``` D. Amiodarone 5mg/kg - See www.resus.org.au Guideline 12.5 A. False - incorrect dose. at 18/12 estimated weight is ~11kg (2(age+4)). Dose is 0.1-0.3mg/kg. Otherwise adenosine is FIRST LINE, with amiodarone being second line. B. False - Patient is not severely hypotensive yet! From above ref: 'SVT may cause severe hypotension or pulseless in which case synchronised DC shock should be given immediately in a dose of 0.5-1.0 J/kg (mono phasic shock or biphasic shock) but up to 2J/kg if necessary'. C. False - see B D. TRUE. see A. E. False - bit premature... ```

Answer 6

C - False and answer to choose; Samples should be taken immediately, 1 hour after reaction and 6 or up to 24 hours after reaction ref 2004 CEACCP article The CEACCP article from Aug 04 answers these questions, it states A. 8% cross reactivity between cephlasporins and penicillin B. Colloids can precipitate histamine release and make the situation worse and are recommend to avoid C. Tryptase is elevted in both- making this option incorrect D. Collect blood immediately, at 1hr and a third sample between 6 and 24 hrs

Answer 7

``` D. Muscle rigidity and possibly B. ↑ CK if CK = creatine kinase NOT creatinine kinase (only using Levenson's crier for dx of NMS) -- DSM IV-TR criteria: Severe muscle rigidity and elevated temperature associated with use of neuroleptic medication as well as two or more of the following - - diaphoresis - dysphagia - tremor - incontinence - changes in level of consciousness ranging from confusion to coma - mutism - tachycardia - elevated or labile BP - leukocytosis - laboratory evidence of muscle injury ``` ``` Levenson's criteria (3 major, or 2 major and 4 minor criteria are needed for dx) Major criteria - fever - rigidity - elevated creatine kinase (CK) Minor criteria - tachycardia - abnormal BP - altered consciousness - diaphoresis - leukocytosis ```

Answer 8

D. myofibrillar necrosis on muscle biopsy false hence answer - A. MRI spectroscopy - true - Nuclear magnetic resonance spectroscopy measures the concentrations of ATP, phosphocreatine and other phosphomonoesters, along with pH, both in vivo and non invasively, in muscle and other tissue. Several studies have shown delayed reconstitution of pH, ATP, and increased phosphocreatine in MH patients during and after graded exercise. A recent study reports 100% concordance between abnormalities in adenosine triphosphate and high-energy phosphates produced by a specific exercise protocol and the results of muscle biopsy. B. Ca release from B lymphocytes in response to caffeine stimulation- true - Recently, Sei et al.22 have shown RYR-1 receptors on B lymphocytes in humans. This implied that these cells might demonstrate changes in calcium flux similar to those demonstrated in muscle. They found that lympho- cytes from MH patients, when incubated with 4-chloro- m-cresol, showed increased intracellular calcium con- centrations. However, halothane did not affect intracellular calcium concentrations. C. mutations in ryanodine receptor gene - true - Most recently, the demonstration that a mutation in the gene that encodes the calcium release channel (the ryanodine receptor, RYR-1) underlies porcine MH in- creased the expectation of a simple DNA-based test for MH in humans as well. D. myofibrillar necrosis on muscle biopsy - false E. plasma creatine kinase levels above 800 u/L - true- Creatine kinase concentrations are chronically in- creased in perhaps 50% of MH patients. - ----------- "Another approach has been the use of nuclear magnetic resonance spectroscopy to measure ATP, pH, creatine phosphate and other high-energy phosphates non-invasively. With exercise, MH susceptibles demonstrate a greater depletion of high-energy phosphates and fall in pH, compared to normals." Caffeine stimulated release of calcium from B Lymphocytes - "The B lymphocytes from MH patients also display exaggerated changes in cellular calcium levels upon exposure to caffeine and other calcium-release agents compared to normals." Resting CK >800 Muscle contraction on exposure to halothane - caffeine/halothane contracture test (CHCT) continues to be the gold standard Myofibrillary necrosis on histology - ASA Abstracts 2001 Histopathological Examination Does Not Improve Differentiation between Malignant Hyperthermia Susceptible and Normal Patients Frank Wappler, M.D.; Franziska von Breunig, M.D.; Marko Fiege, M.D.; Ralf Weisshorn, M.D.; Jochen Schulte am Esch, M.D. Department of Anesthesiology, University Hospital Eppendorf, Hamburg, Germany In contrast to the results of recent investigations in a small population of MH patients, histological differences between MHS and MHN could not be demonstrated. Histological investigations can neither improve MH diagnosis nor contribute to a better definition of the MHE status. Therefore, the IVCT remains the only reliable test method in diagnosis of MH susceptibility. However, histological examinations might be helpful to determine unknown neuromuscular diseases (e. g. central core disease, carnitine deficiency syndrome) in patients undergoing IVCT.

Answer 9

B. Neck circumference F. for Mar13 exam JB Brodsky, HJM Lemmens, JG Brock-Utne, MVierra, LJ Saidman, Morbid Obesity and Tracheal Intubation. Anesth Analg 2002;94:732–6 ➮ Factors looked at included: "height, weight, neck circumference, width of mouth opening, sternomental distance, thyromental distance and Mallampati score" ➮ "Logistic regression identified neck circumference as the best single predictor of problematic intubation. Mallampati score inclusion did not further improve the model in our limited study with only 12 problematic intubations. In patients with a large neck, the view during direct laryngoscopy was poorer."

Answer 10

- white over right, smoke over fire. | - ----------

Answer 11

D. may be detected by an unexpected drop in end-tidal volatile anaesthetic agent concentration CJA 48:847-849 (2001) A breathing circuit disconnection detected by anaesthetic agent monitoring

Answer 12

D. wide range of damping coefficient associated with good performance if system has high natural frequency. However from Miller: Most catheter-transducer systems are underdamped but have an acceptable natural frequency that exceeds 12 Hz. If the system's natural frequency is lower than 7.5 Hz, the pressure waveform is often distorted, and no amount of damping adjustment can restore the monitored waveform to adequately resemble the original waveform.[47] If, on the other hand, the natural frequency can be increased sufficiently (e.g., 24 Hz), damping will have minimal effect on the monitored waveform, and faithful reproduction of intravascular pressure is achieved more easily (Figs. 40-6 and 40-7). In other words, the lower the natural frequency of the monitoring system, the more narrow the range of damping coefficients that can be tolerated to ensure faithful reproduction of the pressure wave. For example, if the monitoring system's natural frequency is 10 Hz, the damping coefficient must be between 0.45 and 0.6 for accurate monitoring of the pressure waveform. If the damping coefficient is too low, the monitoring system will be underdamped, resonate, and display factitiously elevated systolic blood pressure; if the damping coefficient is too high, the system will be overdamped, systolic pressure will be falsely decreased, and fine detail in the pressure trace will be lost. ``` ie. The higher the natural frequency of the system it will tolerate a wider range of damping… not the other way around… so does that make D false too? poorly remembered. - by exclusion. A. false - From Common Errors in Clinical Measurement. Anaes Int Care Med 05 Vol 6 Issue 12: "Damping of the pressure waveform due to poor positioning of the cannula, or the use of overly compliant tubing, underestimates systolic pressure and overestimates diastolic pressure. The mean pressure is still reasonably accurate." B. false - see A C. false - see A. E. False - see A. ----------- ```

Answer 13

E or A - see wiki - n 'J Med Ethics 2004;30:286–290' - not available through ANZCA so here is the relevant part: "Consider the case of a patient, Mr A, who is due to undergo surgical repair of a 10 cm abdominal aortic aneurysm, but who refuses intraoperative blood transfusion, because he is worried about the infinitesimally small risk of contracting variant Jakob-Creutzfeld disease (vCJD) through transfusion. The anaesthetist may explore these fears in a preoperative visit, and may discuss alternative methods of fluid replacement or conservation during this potentially very bloody operation. If the patient still refuses blood transfu-sion, however, the anaesthetist is faced with a conundrum— it would be morally and professionally very difficult to justify proceeding without potential recourse to transfusion, because of the markedly greater risk of severe patient morbidity or mortality. This example differs from the problems posed by blood refusing Jehovah's Witnesses, in that such patients refuse blood on the basis of a strongly held religious belief, a belief that to them, forms a core value, and is therefore to be respected. Mr A, however, although making an autonomous decision about an admittedly possible but realistically negligible risk is undoubtedly making a poor decision, and one that may be viewed as being at odds with his normal beliefs and values. The easiest course is to respect Mr A's decision, and proceed. Alternatively, the anaesthetist may respect Mr A's decision, but refuse to anaesthetise him because of the substantially increased perioperative risk to Mr A. Hard cases make hard decisions, however, and in this case, the anaesthetist would be justified in coercing Mr A into accepting blood; untreated, a 10 cm aneurysm would be likely to rupture within a year, with a 90% mortality if this occurred outside hospital, an occurrence that the anaesthetist may decide does not conform with Mr A's values (Mr A being an otherwise happy family man). The anaesthetist may feel that Mr A has attached undue weight to the risk of vCJD, and may continue to try and convince Mr A to accept blood."

Answer 14

. Carbon monoxide -- From Stoelting: 'Carbon monoxide formation reflects degradation of volatile anaesthetics that contain a CHF2 moiety (des, enf and iso) by the sting bases in desiccated CO2 absorbents. Factors which influence magnitude of carbon monoxide production from volatile anaesthetics include: - dryness of CO2 absorbent with hydration preventing formation - high temperatures of CO2 absorbent as during low fresh gas flows and/or increased metabolic production of CO2 - PROLONGED HIGH FRESH GAS FLOWS THAT CAUSE DESICCATION (DRYNESS) OF THE CO2 ABSORBENT, and - type of absorbent Desflurane produces the highest carbon monoxide concentration (then enf and iso).

Answer 15

A. an alpha-agonist is the inotrope of choice - A. an alpha-agonist is the inotrope of choice - probably true and best answer: there are No α-1 adrenergic receptors are present in the pulmonary circulation (Blaise, Anaesthesiology, 2003, 99(6):1421) so α-1 agonists are fine and may assist RV function by increasing coronary perfusion pressure (although some prefer dobutamine initially becuase it increases contractility and may pulmonary vasodilate) the wording is confusing and might subequently change now. Both the Blaise article and Stoelting 5th ed. suggest that causes of hypotension are multifactorial and should be treated accordingly. Specifically pulm HTN crisis requiring inotropy, the 'inotrope' of choice might be milrione (or possibly dobutamine), however R heart ischaemia and low SVR (with fixed PVR) are important causes of hypotension specifically treated with noradrenaline B. hypothermia is protective against rises in pulmonary artery pressure - false Hypothermia increases PVR (A & A ,Volume 96(6), June 2003, pp 1603-1616) C. isoflurane will tend to decrease pulmonary artery pressure - false PVR does not change with volatiles except N2O which does increase PVR (Stoelting Pharmacology p47) Isoflurane has no effect on baseline pulmonary vessel tone. (Blaise, Anaesthesiology, 2003, 99(6):1421) D. ketamine is an appropriate anaesthetic agent - false 'In patients who have pulmonary artery pressure, ketamine seems to cause a more pronounced increase in pulmonary than systemic vascular resistance' (Miller, p348) 'The sympathomimetic properties of ketamine may preclude use in the setting of pulmonary hypertension (Yao, p96) In-vitro ketamine increases PVR in rat lung...(and)...ketamine attenuates endothelium-dependent pulmonary vasorelaxation in response to acetylcholine and bradykinin ...(and)...sympathetic innervation of the pulmonary circulation does exist (Blaise, Anaesthesiology, 2003, 99(6):1421) E. right heart failure is not a concern - false -----------

Answer 16

D. digitalis toxicity Digoxin is associated with ST depression and other arrhythmias and calcium channel blockers with AV conduction disturbances. (harrison’s 1267-70) Q waves: transmural MI, LBBB, hyperkalaemia, WPW, amyloid, HOCM, cardiac contusion, myocarditis, dextrocardia, reverse limb leads. Epstein page 52. -----------

Answer 17

B. procainamide ~~ Avoid Class I anti-arrhythmics, mexilitine & sotalol (in renal failure) Magnesium – first line treatment according to emedicine Isoprenaline – second line treatment according to emedicine Lignocaine – has been used to treat resistant TDP Phenytoin – useful, as it shortens the QTc – according to Harrisons β blockade is the mainstay for congenital prolonged QT (Lown Ganong Levine) – remember that fat Med Reg in Dunedin on his first on call night in Nelson ----------- M6,1404 Torsades de pointes, which may mimic VF or VT, is a life threatening arrhythmia that occurs in the presence of disturbed repolarisation (hence its association with prolonged QT interval). Discontinuation of drugs that predispose to QT interval prolongation and correction of electrolyte abnormalities are essential in the treatment of torsades de pointes. Acute therapy may include defibrillation, 1 to 2g of intravenous magnesium sulfate, amiodarone (n.b not considered a good therapy in most texts ), isoprenaline and overdrive pacing. By mechanisms that are poorly understood, mexiletine may exacerbate existing arrhythmias and may evoke torsades de pointes. AMIODARONE - prolongation of the QT interval is commonly observed during chronic treatment but induction of torsades de pointes is seen only rarely. The most important unwanted effect of sotalol may be its arrhythmogenic activity, which includes provoking torsades de pointes. The likelihood of this effect is increased by hypokalaemia, and is greater in women than in men. Since sotalol is eliminated mainly by excretion, unchanged in the urine, the danger of torsades de pointes is also increased where there is renal dysfunction. http://www.lhsc.on.ca/critcare/icu/cctc/procprot/pharmacy/mono2/procainamide.html Adverse Effects of procainamide Cardiac: o arrhythmias: ventricular tachycardia or fibrillation, Torsades de Pointes (associated with high levels of procainamide and/or NAPA (N-acetyl procainamide); secondary to prolonged QT interval) o heart block o prolongation of PR, QRS, QT intervals (up to 50%) o bradycardia, asystole o decreased BP, decreased

Answer 18

A. Normoglycaemia, hypernatremia , hypokalemia -- see wiki (tendency for impaired glucose tolerance…) Also tend to have low magnesium. -----------

Answer 19

C. psoriasis get psoriasis with crohns but not UC -----------

Answer 20

Most cephalad level a safe spinal in a neonate would be? A L2-3 B L3-4 C L4-5 D L5-S1

Answer 21

A? This patient has pseudohyponatraemia secondary to hyperglycaemia. Most likely he is septic given clinical picture. I chose antibiotics over insulin as delay for antibiotics increases mortality. realistically you would treat both give IV fluids and resuscitate. I hate mcqs.

Answer 22

A. High SVP see wiki. Des also has a low BP not high BP.

Answer 23

?C | -----------

Answer 24

B (but increase in everything else!) -----------

Answer 25

B. (age+4)x2 The "standard" anaesthetic formula are: From age 1-8: wt= (age in years x 2) + 8 [which is equal to (age+4)x2] From age 8-12 wt = (age in years) x 3 -----------

Answer 26

A. Remove LMA and deepen with sevoflurane | -----------

Answer 27

?A. Underappreciated degree of blood loss - difficult to find references. From Anaesth Intensive Care 2010;38:1088-1084: 'Fourteen cardiac arrests were recalled and details were specified for four: hyperkalaemia, major haemorrhage and CVS collapse in one patient with cerebral palsy and three DMD patients. Ten deaths were recalled, detail specified for six: three associated with major haemorrhage or transfusion (one DMD in the arrest group and one DMD with TRALI, one idiopathic scoliosis patient), one AMI in a pt with cardiomyopathy but no other myopathy, one brainstem stroke (with thoracic spin bifid a) and one due to sepsis. Closed questions on venous/arterial thrombosis, infection (wound or instrumentation), failed fusion rates, awareness or intraoperative recall during wake-up tests were not included.' -----------

Answer 28

d. Increased myocardial work - - a. false - increases ICP (Miller) b. false - increases IOP (Miller) c. false - decreases pulmonary compliance (Miller) d. ?true - presumably increased preload and venous return results in increased cardiac output and therefore myocardial work. e. ?false - presumably increased preload and venous return translates to increased pulmonary venous flow and pressure if resistance is unchanged - ----------

Answer 29

A: Presence of patent ventriculo-atrial drain/shunt and B: PFO if large! -- From Anaesth Int Care 2005; 33:323-331 Table 3 Absolute contraindications to the sitting position - PATENT VENTRICULO-ATRIAL SHUNT - Severe CVS disease - LARGE PFO or other pulmonary-systemic shunt - Cerebral ischaemia when upright and awake - Anaesthesia or surgical team unfamiliar with position Relative - small PFO - extremes of age - uncontrolled HT - COAD (may not tolerate VAE as well if it occurs) -----------

Answer 30

A. Loss of septal Q's in V5 and V6 - Diagnostic Criteria - QRS duration of 120 ms - Dominant S wave in V1 - Broad monophasic R wave in lateral leads (I, aVL, V5-V6) - Absence of Q waves in lateral leads (I, V5-V6; small Q waves are still allowed in aVL) - Prolonged R wave peak time > 60ms in left precordial leads (V5-6) -----------

Answer 31

A. Presence of thrill see wiki. Dyspnoea may or may not be present in severe AS (though 50% of patients with severe AS will have dyspnoea). From "Aortic Stenosis and Non Cardiac Surgery" CEACCP 2005; 5(1):1-4 A - True - "A precordial thrill may be felt, especially on leaning forward in expiration. Its presence is reasonably specific for severe aortic stenosis" B - False - Severe AS mean gradient 40-50mmHg C - False - Severe AS valve area 0.6-0.8cm2 D - ? False - may be present in other grades of AS E - False - "There are three cardinal symptoms in aortic stenosis; angina, syncope and dyspnoea. However, symptoms do not correlate well to the severity of the stenosis" -----------

Answer 32

D. Stanford B -- Stanford A involves ascending aorta (DeBakey types I and II); Stanford B involves the descending aorta below the subclavian artery (DeBakey III) and has traditionally been managed with medication. Stanford C does not exist? -----------

Answer 33

A. Able to achieve lobar isolation Bronchial Blockers ADVANTAGES Easy recognition of anatomy if the tip of a single lumen tube is above carina Best device for pt with difficult airway No cuff damage during intubation No need to replace ETT if post-op ventilation required Selective lobar isolation is possible (mentioned at end of article, not in table) DISADVANTAGES Small channel for suctioning Conversion from 1- to 2- then to 1-lung ventilation (problematic for novice) High maintenance device (dislodgement or seal loss during surgery) ``` Double-Lumen ETT's ADVANTAGES Large lumen facilitates suctioning Best device for absolute lung separation Conversion from 2 to 1-lung ventilation easy and reliable DISADVANTAGES Difficulty selecting proper size Difficult to place during laryngoscopy Damage to tracheal cuff Major tracheo-bronchial injuries ```

Answer 34

C. 1.7 - The objective is to establish that after surgical resection of the lung for a tumor, there will be sufficient pulmonary reserve to keep the patient comfortable, and will not become a respiratory cripple. To answer the question we can refer to the BJA CEACCP article from 2006, or Miller (7th edition). Basically they have the same concept, although the numbers used differ, but the end results are similar. These can be used for pneumonectomy or lobectomy, but I assume this question is referring to a right lower lobectomy rather than the introductory suggestion of a pneumonectomy (initially a bit confusing). Based on the CEACCP article (2006), we can calculate a predicted post-op FEV1 (ppoFEV1) by calculating how many broncho-pulmonary segments of lung will remain after surgery. The starting number varies depending on the text/classification you use, but this article suggests 19 lung segments in total - 10 on the right (RUL=3, RML=2, RLL=5), and 9 on the left (LUL=3, Lingula=2, LLL=4). Given that the right lung is physically and functionally larger than the left this makes sense. Therefore for a right lower lobectomy we will be removing 5 segments, and therefore be left with 14 segments. The ppoFEV1 will be 14/19 x 2.4L = 0.7368 x 2.4L = 1.77L. Based on the numbers used in Miller there are 42 segments in total: 22 segments (or subsegments) in the right lung (RUL=6, RML=4, RLL=12), and 20 in the left lung (LUL=10, LLL=10). The calculation is the same, but with different numbers: A right lower lobectomy will remove 12 segments, and we will be left with 30. Therefore ppoFEV1 will be 30/42 x 2.4L = 0.7143 x 2.4L = 1.71L. The numbers used in Miller obviously give an answer that is closer to one of the options in the remembered question, so based on this I would say ANSWER=C. -----------

Answer 35

A. Epidural blood patch 30-50% effective - false so answer to choose blood patch effective in 80% at 24 hrs - see my comment on wiki. -----------

Answer 36

C. IV magnesium See Global Initiative for Asthma 2012 update figure 4.4-2 Management of Asthma exacerbations in acute care setting. Intravenous magnesium is part of treatment for severe episode (along with oxygen, inhaled b2 agonist and inhaled anticholinergic and systemic glucocorticosteroids.)

Answer 37

``` C. Haemophilia B (Christmas disease) - All others make her hypercoagulable - Factor V Leiden confers resistance to breakdown by protein C & S system. It results in hypercoagulability, and is therefore the wrong answer. ``` Protein C deficiency results in reduced FV & VIII breakdown and hypercoagulability, and is therefore the wrong answer. Haemophilia B, is X-linked but the phenotype in females is variable. It does cause increased bleeding. And is the answer to choose. ATIII deficiency is associated with a hypercoagulable state, and is the wrong answer. Lupus anticoagulant, causes in vitro prolongation of the APTT but in vivo, results in hypercoagulability, and is the wrong answer. -----------

Answer 38

``` A. Pulmonary hypertension - From CEACCP article on AFE 7(5) p 152 ' Amniotic fluid and fetal cells cause an increase in both systemic and pulmonary vascular resistances resulting in acute pulmonary hypertension. Survivors of this response develop left ventricular failure and pulmonary oedema ' ----------- ```

Answer 39

A. High negative predictive value - Thallium scanning in coronary artery disease (CAD) using radioactive thallium-201(201-Tl) is a widely available technique which is sensitive, accurate and noninvasive. It detects CAD accurately in patients with: atypical chest pain and a positive exercise ECG or typical chest pain and a negative exercise ECG. In known CAD, it determines the severity, extent and haemodynamic significance of a stenosis. In patients with recurrent chest pain following coronary artery graft surgery (CAGS) or angioplasty, scanning can detect the presence and severity of any ischaemia, when graft occlusion or restenosis has occurred. 201-Tl has important prognostic value in predicting cardiac complications (death and acute myocardial infarction) in patients undergoing major surgery - usually vascular. In patients with acute myocardial infarction, it may contribute to risk stratification. -from Aust Prescr 1994;17:57-61 Possibly 'A' depending on the stem. In the recent vascular surgery webinar/podcast Dr Machlin emphasised that, in the context of using perfusion scans to predict perioperative ischaemic events, a negative study was of much more benefit i.e. they have a high NPV but a low PPV. No one perfusion scan was any better than the others, it just depended what was available in your institution.SGB From the 2007 AHA guidelines, 'because of a very high sensitivity of abnormal stress nuclear imaging studies for detecting patients at risk for perioperative cardiac events, the negative predictive value of a normal scan has remained uniformly high at approximately 99% for MI or cardiac death' -----------

Answer 40

a. Increased cardiac output - Example of Hypervolemic hemodilution. a. Increased CO occurs - not sure if it is immediate?! b. Capillary dilatation - unsure though theoretically can occur due to non-anion gap metabolic acidosis that would result from 3L of NS! c. Increased O2 delivery - unsure… again if CO increases and acidosis is result of NS infusion then ODC is shifted right… all things point to increased O2 delivery d. Right shift in ODC - true if acidosis occurs from NS. Not sure if it is immediate? - From Miller Ch 57: Withdrawal of whole blood and replacement with crystalloid or colloid solution decreases arterial O2 content but compensatory hemodynamic mechanisms and the existence of surplus O2-delivery capacity make acute normovolemic hemodilution safe. A sudden decrease in RBC concentration decreases blood viscosity, thereby decreasing peripheral resistance and increasing cardiac output. If CO can effectively compensate, O2 delivery to the tissues at a hct of 25-30% is as good as, but no better than O2 delivery at a HCT 30-35%. -----------

Answer 41

A: Dorsal column -- From www.scoliosisjournal.com/content/5/1/8 "Somatosensory evoked potentials (SSEP) measure the integrity of the sensory pathways in the dorsal columns of the spinal cord, by stimulating a peripheral sensory nerve and measuring the electrical response in the brain. The introducetion of SSEP monitoring to spinal surgery has significantly reduced the rate of intraoperative injury." -----------

Answer 42

C 0.01% -- CHADS2 (CCF, Hypertension, Age ≥75 years, DM, Stroke/TIA or Thromboembolism) - pts score would be 1 which gives annual stroke risk of 2.8% - does that translate to a daily stroke risk of ~0.01% ? CHA2DS2-VASc (CCF, HT, Age ≥75 years, DM, Stroke/Tia or thromboembolism, Vascular disease (IHD, PVD etc), Age 65-74, Sex category (female)) - pts score would be 3 - scores 2 for being 75 - so his annual stroke risk would be 2.2% -----------

Answer 43

``` C: Sepsis (though previous grp said B) -- From AANA Journal/June 2005/Vol 73 (3): 'The AANA and ASA closed claims analysis underscores seriousness of pharyngoesophageal perforation. Despite the relatively rare occurrence of this type of injury compared to other airway injuries, pharyngoesophageal perforation, especially when diagnosis and treatment were delayed, was associated with the poorest outcome. The late sequelae of undiagnosed pharyngoesophageal perforation are mediastinitis, retropharyngeal abscess, pneumonia, pericarditis, and death. Earlier signs are pneumothorax and pneumomediastinum (Table 1).' ----------- ```

Answer 44

c. Suction the trachea -- From www.resus.org guideline 13.5 INTUBATION UNDER SPECIFIC CIRCUMSTANCES Meconium stained liquor (See also Guideline 13.4). Routine intrapartum oropharyngeal and nasopharyngeal suctioning is not recommended for infants born with either clear or meconium-stained amniotic fluid [Class A, LOE II8, 9] There is insufficient evidence to recommend a change in the current practice of endotracheal suctioning of non-vigorous infants born through meconium-stained amniotic fluid [Class B, expert consensus opinion10-12]. If it is done, it should be performed only: • Immediately after birth. • If an experienced practitioner and all needed equipment are immediately available. • Before the onset of breathing or crying and in infants with decreased muscle tone. It should not be done if the infant is vigorous and breathing or crying. It should be done once, and then any subsequent resuscitation that is needed should be commenced expeditiously [Class B, expert consensus opinion].

Answer 45

E. Alteration in gene expression -- A. false. Magnesium inhibits calcium ions from entering cells by blocking NMDA receptors, which causes an antinociceptive effect. Furthermore, this antinociceptive effect is related to its prevention of central sensitisation caused by peripheral tissue injury. Increased intracellular CALCIUM levels seem to play a role in initiation of central sensitisation, and the build-up of intracellular Ca is associated with various receptors on postsynaptic neurone of the spinal dorsal horn such as NMDA, AMPA, and glutamate receptors. Of these, NMDA receptor activation has been demonstrated to be essential for initiating and maintaining central sensitization. Extracellular magnesium blocks NMDA receptor in a voltage-dependent manner. Ref: Magnesium in the Central Nervous System 2011 (University of Adelaide Press) B. false. see above reference C. false. Glutamate is the major neurotransmitter. (See The Journal of Pain, Vol 10, No 9 (September), 2009: pp 895-926) D. false. C-fiber activity is responsible. E. true. -----------

Answer 46

a. compliance x resistance Compliance - measurement of lung distensibility and expressed as change in volume divided by change in pressure. Normal lung+thorax compliance is 0.1L/cmH2O. Low compliance - more pressure will be needed to deliver given volume (e.g. ARDS). Emphysema is typical of increased lung compliance Resistance - pressure needed to deliver flow of gas and expressed as change in pressure divided by flow. Normal is 0.5-1.5 cmH2O/L/sec. Time Constant of the lung is a phenomenon whereby a given percentage of passively exhaled breath will require a constant amount of time to be exhaled regardless of the starting volume given constant lung mechanics. Mathematically is compliance multiplied by airway resistance and resulting value has units of seconds. http://www.lexingtonpulmonary.com/education/lungmech/lungmech.html

Answer 47

b. Pneumonia -- http://www.bmj.com/content/331/7529/1374 heart failure came in 2nd -----------

Answer 48

a. Mitral stenosis -- source - dr google. -----------

Answer 49

b. 0.34 -- ref: 'Cerebral Awakening Concentration of Sevoflurane and Isoflurane Predicted during Slow and Fast Alveolar washout' Anesthesia and Analgesia 1993. Mac awake for sevo was the same for both slow and fast washout. -----------

Answer 50

13 ``` Motor 6= obey commands 5= localizes pain 4= flexion withdrawal from pain 3= abnormal flexion (decorticate) 2= abnormal extension (decerebrate) 1= nada Voice 5= alert and orientated 4= confused 3= inappropriate words 2= incomprehensible sounds 1= nada Eyes 4= open 3= to voice 2= pain 1 = nada ----------- ```

Answer 51

A. Glossoptopsis From Stoelting Anaesthesia and Coexisting disease "Pierre Robin syndrome consists of micrognathia usually accompanied by glossoptosis (posterior displacement of the tongue) and cleft palate. Mandibular hypoplasia may be responsible for displacement of the tongue into the pharynx, which subsequently prevents fusion of the palate. Acute upper airway obstruction can occur in neonates or infants with Pierre Robin syndrome. Feeding problems, failure to thrive, and cyanotic episodes are other early complications of this syndrome. Associated congenital heart disease is frequent. Fortunately, sufficient mandibular growth during early childhood markedly reduces the degree of airway problems in later years." -----------

Answer 52

d. 70 -- 1mmHg = 1.36 cmH2O 13/1.36 = 10mmHg CPP = MAP - ICP or CVP whichever is greater (normally) In head up/sitting position with a craniotomy - Need to take into consideration hydrostatic pressure (ρgh) ICP is open to atmosphere therefore ICP = zero CVP corrected for height is negative due to subtraction of the hydrostatic gradient (-5) Thus CPP = (MAP - ρgh) - the maximum of (ICP-ρgh), (CVP-ρgh) or Patm, where ρgh is hydrostatic pressure at height from skull to BP measurement site, Patm =0 ref: http://www.apsf.org/newsletters/html/2008/summer/11_modified_calculation.htm - ----------

Answer 53

B. Facial nerve -- Just before entering this foramen, the FACIAL nerve gives off the chorda tympani, which pierces the posterior wall of the tympanic cavity close to the deep surface of the ear drum. It runs forward over the pars flaccida of the tympanic membrane and the neck of the malleus, lying immediately beneath the mucous membrane throughout its course. It passes out through the front of the middle ear by piercing the bone at a canaliculus at the inner end of the petrotympanic fissure. It emerges from this fissure to join the LINGUAL nerve about 2.5 cm below the base of the skull. Through the chorda tympani, taste fibres are conveyed from the anterior two-thirds of the tongue and secretomotor fibres reach the submandibular ganglion. The literature only speaks of damage to LINGUAL nerve (as strictly speaking this is the nerve that is damaged though it carries fibers from the FACIAL nerve). Other nerves that may be damaged is hypoglossal or recurrent laryngeal. The facial nerve is 'INVOLVED' - depends how question was actually worded!

Answer 54

b. Auscultation with a stethoscope > d. pulse oximetry -- Guideline 13-3 from Aust Resus Council Dec2010 Heart rate can be determined by listening to the heart with a stethoscope (most reliable) or in the first few minutes after birth, by feeling for pulsations at the base of the umbilical cord [Class A, expert consensus opinion]. The base of the umbilical cord is preferable to other palpation locations, but if a pulse is not felt at the base of the cord this is not a reliable sign that the heart rate is absent. Other central and peripheral pulses are difficult to feel in newborn infants making the absence of these pulses an unreliable sign.4-6 Pulse oximetry can provide an accurate and continuous display of the heart rate within about a minute of birth [LOE IV 7, 8]. -- From 2010 International Consensus on CPR Part 11: Neonatal Resus - Of clinical assessments, auscultation of the heart is the most accurate, with palpation of the umbilical cord less so. However, both are relatively insensitive (LOE 2 and 4). - Several studies have addressed the accuracy of pulse oximetry in measuring heart rate in the delivery room and have shown the feasibility of pulse oximetry during newborn resus, but none of these studies examined impact of these measurements on resus outcomes (LOE 4) - Pulse oximetry (SpO2) and HR can be measured reliably after 90s from birth with a pulse oximeter designed to reduce movement artefact and a neonatal probe (LOE 4). - Preductal values, obtained from the R wrist or hand, are higher than post ductal values. Applying the oximeter probe to the subject before connecting it to the instrument will produce reliable results more quickly (LOE 4). -----------

Answer 55

a. Phenytoin - from wiki: "Treatment of seizures in porphyriacs is a difficult situation given that most anticonvulsants are contraindicated (such as phenytoin, carbamazepine, thiopentone) because they induce hepatic P450 enzymes. (This consumes heme and thus reduces the negative feedback on ALA synthesase which is then free to generate heme/porphyrins products.) Drugs considered safe to use in convulsing porphyriacs include: midazolam, propofol, gabapentin and magnesium." Also, from UTD 'Management of acute intermittent porphyria': - Seizures are treated by carefully correcting hyponatremia, if present. Almost all anticonvulsant drugs have at least some potential for exacerbating acute porphyries. Clonazepam may be less harmful than phenytoin, barbiturates or valproic acid. Bromides, gabapentin and vigabatrin are safe.

Answer 56

A. 4/6 loudness (Aug12 version) -- From http://www.aafp.org/afp/1999/0801/p558.html "Characteristics of pathologic murmurs include a sound level of grade 3 or louder, a diastolic murmur or an increase in intensity when the patient is standing". Also from Am J Cardiol. 2008 Oct 15;102(8):1107-10. Samuel A. Levine and the history of grading systolic murmurs: "Of 19 subjects with grade 3 or 4 murmurs, all were determined to have organic heart disease or anemia. Thus, louder systolic murmurs were found to be a significant finding, as were the cause location and effects of posture". 1/6: very soft and not heard at first 2/6: soft, but can be detected almost immediately by an experienced auscultator 3/6: moderate; no thrill 4/6: loud; thrill just palpable 5/6: very loud; thrill easily palpable 6/6: very very loud; can be heard without placing stethoscope on the chest! See Table 1 CEACCP article: Innocent - Asymptomatic, early systolic or continuous (venous hum), blowing/musical/vibratory in quality, No precordial thrill, often varies with posture Pathological - symptomatic (hx recurrent chest infections, cyanosis, tachypnoea, sweating, feeding difficulties, failure to thrive), Diastolic, pan systolic or late systolic Variable/harsh in quality precordial thrill sometimes present Rarely varies with posture (HOCM murmur increases with standing) ALSO - Most CHD is identified before 3 months old but any child under 1 yr with a murmur should be referred to a paediatric cardiologist before anaesthesia, even if asymptomatic as significant lesions may be slow to present. Be suspicious of children with syndromes assoc with CHD - Down's syndrome - CHARGE (coloboma of eye, heart defects, atresia of choanae, retardation, genital/urinary abnormalities, ear abnormalities/deafness) - VATER (vertebral anomalies, anal atresia, TOF, radial dysplasia) - Turner's - DiGeorge In older children watch for decreased extol, squatting during play (tet spells), syncope -- serious heart disease Family history of sudden death -- suspect HOCM, has autosomal dominant inheritance but often asymptomatic. ECG - look for ventricular hypertrophy In an asymptomatic child over 1 yr old with an innocent murmur and normal ECG -- probably safe to proceed with surgery and refer for investigation after operation

Answer 57

B. paroxysmal nocturnal dyspnoea Patients die within an average of 5 yrs after onset of angina, 3 yrs after onset of syncope and 2 years after onset of heart failure symptoms. -----------

Answer 58

C. Enalapril 2.5mg BD See AHA 2007 CVS evaluation for non cardiac surgery AND AHA 2009 update for treatment of heart failure. Dose of metoprolol is extremely high to start with but he should also be started on a beta blocker. -----------

Answer 59

B. Vertebral arteries -- various online resources have stated vertebral artery (rather than ICA) -----------

Answer 60

C or ?D (prev grp answer) D - for March13 -- From Evidence Based Practice Anaesthesiology Ch17: - 2a - partial view of glottis visible - 2b - only arytenoids visible (2b is associated with greater difficulty) - 3a - epiglottis can be seen and lifted - 3b - epiglottis seen but CANNOT be lifted 6 grades and 3 functional classes: easy: laryngeal inlet visible and indubitable under direct vision (1 and 2a) restricted: posterior glottic structures visible or epiglottis visible and can be lifted (2b and 3a) these views likely to benefit from indirect intubation methods difficult: epiglottis cannot be lifted or when no laryngeal structures are visible - likely need specialist methods for intubation and may need to be performed blindly (3b and 4) - ----------

Answer 61

B. Aortic Dissection | -----------

Answer 62

C. Pulmonary valve (where is the ASD spot?) -- From Talley O'Connor 5th ed. ASD: - Ostia secundum (90%) where defect does not involve AV valves and ostia primum where defect involves AV valves - Auscultation: fixed splitting of S2, defect produces no direct murmur but increased flow through R side of heart can produce low pitched diastolic tricuspid flow murmur and more often a pulmonary systolic ejection murmur louder on inspiration. - From emedicine: - Findings on examination depend on degree of L-R shunt and hemodynamic consequences. - Hyperdynamic RV impulse due to increased diastolic filling and stroke volume. - Palpable pulsation of PA and ejection click can be detected because of a dilated pulmonary artery - S1 is typically split and second component may be increased in intensity due to forceful RV contraction and delayed closure of TV - S2 is often widely split and fixed due to reduced respiratory variation from delayed PV closure (only seen if PAP is normal and PVR is low). This is the CHARACTERISTIC abnormality found in almost ALL pts with large L-R shunts. - blood flow across ASD does not cause a murmur at site of shunt because no substantial pressure gradient exists between the atria. - however ASD with moderate-large L-R shunts -> pulmonary systolic ejection murmur (crescendo-decrescendo) due to increased stroke volume rather than any valvular problems. - large L-R shunts often have rumbling mid diastolic murmur at TV because of increased flow. Auscultatory findings may resemble those of mild valvular or infundibular pulmonic stenosis and idiopathic dilation of pulmonary artery. - these all produce a systolic ejection murmur but DIFFER from ASD by movement of S2 with respiration, a pulmonary ejection click or absence of a tricuspid flow murmur. - ----------

Answer 63

A. Blood flow through non ventilated lung "The major cause of hypoxemia is the shunt of de-oxygenated blood through the non-ventilated lung. " - from www.thoracic-anesthesia.com by Peter Slinger -----------

Answer 64

C. adductor pollicis brevis | -----------

Answer 65

C. 90 degrees counterclockwise Counter clockwise rotation turns bevel inferiorly. Tip passes under epiglottis, gap is closed and tube enters larynx symmetrically. -----------

Answer 66

all these options seem wrong. -- a. false! - 9mm gap is excessive. Diagnosis of atlantoaxial instability can be made with gap > 3-4 mm (depending on reference) ?with flexion extension views. b. c. posterior atlantodental interval>14mm - false. From medicine Rheumatoid Arthritis spine imaging: 'Studies suggest PADI is a better method of assessment because it directly measures the spinal canal and therefore shows how much is narrowed by the subluxation. PADI is the distance between posterior surface of the odontoid and the anterior margin of the posterior ring of the atlas. At all cervical levels cord requires minimum canal width f 10mm; CSF 2mm, dura 2mm. Thus, minimum PADI of 14mm is needed to avoid cord compression. Normal spinal canal measures 17-29mm at C1. Boden et al 93 study -> PADI leads to instability in 25% of patients with RA. Two main categories of c-spine instability: atlanto-axial subluxation and sub axial subluxation. The latter is uncommon and occurs below C2 and leads to earlier symptoms of nerve compression. AAS - Anterior (in 80%). C1 vertebra moves forward on C2 due to transverse ligament destruction -> risk of spinal cord compression by odontoid peg. Subluxation exists when distance between atlas and odontoid peg exceeds 4mm in pts >44yo and 3mm in younger pts. Anterior AAS is worsened by neck flexion - Posterior (in 5%). Destruction of peg may cause backward movement of C1 on C2 - may be seen on lateral extension views. Worsened by neck extension. - Vertical (10-20%). Destruction of lateral mass of C1 -> sublimation of peg through foramen magnum and compression of the cervico-medullary junction. - Lateral or rotatory subluxation. Results from degenerative changes in C1/C2 facet joints. It can lead to spinal nerve compression and vertebral artery compression.