2013.2 Flashcards

Question

29. What cannot be used for tocolysis in a 34/40 pregnant woman: ``` A. Clonidine B. Indomethacin C. Magnesium D. Salbutamol E. Nifedipine ```

Answer 1

B. Indomethacin - avoid after 32/40 (risk of premature closure of DA, decreased renal function/oligohydramnios, NEC and IVH in the fetus) Answer could also be clonidine as this is not a tocolytic

Answer 2

C. Portal pedicle

Answer 3

B. Decreased anaesthetic requirement CEACCP 2012 - Illegal substances in anaesthetic and intensive care practices: Cannabis - The conduct of anaesthesia is little different from that of tobacco smokers, except that in acute intoxication, the effects of agitation and sedation need to be addressed CEACCP 2002 - Drug abusers and anaesthesia: Cannabis - CNS effects are arcane and complex. Although the main effect of THC is to produce tranquility, relaxation and, in larger doses, sedation, it also produces some euphoria and sympathetic stimulation and most subjects have an elevated heart rate following recent intake. Hallucinations have been described after large doses. Cannabis is most commonly smoked in combination with tobacco, but may also be ingested for a less intense but more prolonged effect. Chronic bronchitis and other respiratory complaints are said to be more common in cannabis than tobacco smokers. Anaesthetic considerations (of sedative drugs) - Recent administration of sedatives decreases MAC of inhaled anaesthetics and reduces the requirement for IV induction agents.

Answer 4

D. TOE (in theatre) If pt haemodynamically stable, CT angiogram of chest/great vessels would be appropriate.

Answer 5

C. Cease warfarin and recommence post-procedure.

Answer 6

B. CT head

Answer 7

A. Adenosine

Answer 8

E. Equipotentiality

Answer 9

E. Haemodialysis Toxicology Handbook (2nd ed): Risk stratification: 300 mg/kg - severe intoxication; metabolic acidosis, altered mental state, seizures > 500 mg/kg - potentially lethal Haemodialysis effectively removes salicylate but is rarely required if early decontamination (activated charcoal) and urinary alkalinisation (with bicarb) are implemented. Consider this intervention in the following circumstances: - Urinary alkalinisation not feasible - Serum salicylate levels rising to > 4.4 mmol/L despite decontamination and urinary alkalisation - Severe toxicity as evidenced by altered mental status, academia or renal failure - Very high serum salicylate levels (acute poisoning: > 7.2 mmol/L, chronic poisoning: > 4.4 mmol/L - The threshold to dialyse is lower in the elderly

Answer 10

C. L3-4 Draw an imaginary line between the top of the iliac crests. This intersects the spine at approximately the L3-4 interspace (mark this if necessary) o The conus medullaris finishes near L3 at birth, but at L1-2 by adulthood o Aim for the L3-4 or L4-5 interspace (Pete Howe reckons L3/4 is the answer)

Answer 11

B. 4 hours for formula ANZCA guidelines (from PS 15 - Recommendations for the Perioperative Care of Patients Selected for Day Care Surgery): - Children > 6 weeks: limited solid food and formula milk up to 6 hours, breast milk up to 4 hours, clear fluids up to 2 hours - Infants

Answer 12

D. Sedation score

Answer 13

B. COPD Diffusing capacity (or DLCO) is the carbon monoxide uptake from a single inspiration in a standard time (usually 10 sec). Since air consists of very minute or trace quantities of CO, 10 seconds is considered to be the standard time for inhalation, then rapidly blow it out (exhale). The exhaled gas is tested to determine how much of the tracer gas was absorbed during the breath. This will pick up diffusion impairments, for instance in pulmonary fibrosis.[16] This must be corrected for anemia (because rapid CO diffusion is dependent on hemoglobin in RBC's; a low hemoglobin concentration, anemia, will reduce DLCO) and pulmonary hemorrhage (excess RBC's in the interstitium or alveoli can absorb CO and artificially increase the DLCO capacity). Atmospheric pressure and/or altitude will also affect measured DLCO, and so a correction factor is needed to adjust for standard pressure. Online calculators are available to correct for hemoglobin levels and altitude and/or pressure where the measurement was taken.

Answer 14

D. Remove and place epidural 1 level higher

Answer 15

E. Cisatracurium | Although if this is elective, surgery should be deferred until she has had proper work-up for her anaphylaxis

Answer 16

E. FFP (150-300 mL) + Prothrombinex (50 units/kg) | if Prothombinex unavailable, give FFP 15 mL/kg

Answer 17

D. Have an external diameter which is larger than a normal PVC endotracheal tube

Answer 18

E. (Corneal abrasion is) relieved by topical LA.

Answer 19

A. Carbimazole (takes too long to work) Thyroid storm management (outpatient management): Block hormone synthesis and release: o Propylthiouracil 200mg orally 4-6/24 (blocks hormone formation and block conversion to T3 OR o Carbimazole 20mg 8/24 AND o Lugols iodine solution 0.5ml orally TDS to block hormone release AND Decrease conversion of thyroxine (T4) to triiodothyronine (T3): o Dexamethasone 4mg IV 12/24 Control tachycardia and rate dependent heart failure: o Propanolol 40-80 mg orally 6/24 OR o Esmolol 250-500 mcg/kg IV, as a loading dose, followed by 50-100mcg/kg/minute OR o Metoprolol 5mg IV over 2-3mins, repeated if necessary at 5min intervals up to a total of 15mg Restore hydration Give sedation if needed Oh’s manual: Plasmapheresis can be used

Answer 20

D. Weakness of abductor pollicis brevis

Answer 21

C. Increased cardiac output

Answer 22

E. Patient performs a Valsalva

Answer 23

B. 70 Expected systolic BP for children older than 1 year = 80 + (age in years x 2) mmHg Term neonates - SBP = 60-70 mmHg (MAP to defend in neonates = post-conceptual age in weeks, up to ~ 48 weeks PCA)

Answer 24

A. Desflurane

Answer 25

C. Increased RV:LV area, abnormal septal wall motion, TR, RA dilation

Answer 26

B. Diameter of the tube

Answer 27

D. 25 NNT = 1/ARR Starting incidence must be 12%, therefore reduction is 4% 1/0.04=100/4=25

Answer 28

???? PaO2 will gradually decrease with apnoea (due to diffusion atelectasis and shunt) CEACCP - Physiology of apnoea and benefits of pre-oxygenation (2009): A patent airway will allow oxygen to diffuse into the apnoeic lung. Maintaining a patent airway and exposure to 100% oxygen produces ‘apnoeic mass-movement oxygenation’, which has been shown in animal and simulated human studies to maintain oxygen saturation for up to 100 min. This passive diffusion of oxygen is more effective if the denitrogenation of the alveolar space is as complete as possible and a tight fitting-mask is used. It is important to ensure very high oxygen fraction FIO2 to extend the safe duration of apnoea; increasing the oxygen fraction applied to the airway from 90% to 100% more than doubles the time to critical hypoxia with an open airway. This has a much greater effect on time to critical hypoxia than increasing the FIO2 applied to the airway from 21% to 90%. Although the application of 100% oxygen to a patent airway in an apnoeic patient delays the onset of critical hypoxia, this approach will not reverse hypoxaemia that has already developed. Furthermore, it does not prevent the steady development of hypercapnia and associated acidosis, which over time becomes life threatening.

Answer 29

C. Respiratory rate

Answer 30

D. Raised intracranial pressure

Answer 31

D. Proceed to surgery with no further investigation | surgery is urgent

Answer 32

E. 0.9% saline CEACCP - Traumatic brain injury: an evidence-based review of management (2013): For most patients an isotonic fluid such as normal saline is suitable. There is some evidence that hypertonic saline may be useful as a resuscitation fluid, with one study showing increased survival in a subgroup of patients with TBI and GCS. However, definitive clinical trials are awaited. Hypotonic fluids must be avoided. Colloids confer no benefit, indeed the Saline or Albumin for Fluid Resuscitation in Patients with Traumatic Brain Injury (SAFE) study found an increased risk of death in patients who received albumin rather than saline. After TBI there is a profound catecholamine response, with cortisol release and glucose intolerance making hyperglycaemia common. Glucose-containing fluids should be avoided and blood sugar monitored.

Answer 33

C. Administer methylpred and IVIG 2 days pre-op Stoelting ITP: Thrombocytopenia, diagnosis of exclusion. Most adults proceed to a chronic form of ITP in which a continued high level of marrow platelet production is required to maintain a chronically low to near normal platelet count in the face of shortened platelet life span. Severe bleeding does not occur until the platelet count is below 10,000/mm3. Patients with chronic ITP have platelet counts of 20,000 to 100,000/mm3. Transfused platelets also have a shortened life span. Most ITP patients rapidly destroy infused platelets, up to 30% of patients demonstrate near-normal posttransfusion platelet survival. Anaesthetic management: Severe ITP a/w bleeding in adults should be treated as a medical emergency with high-dose corticosteroids for the first 3 days. If there is need for emergency surgery or clinical evidence of ICH, patient should be given intravenous immunoglobulin and platelets at least every 8-12hrs. If ITP persists for longer than 3-4 months, it is extremely unlikely that patient will spontaneously recover. In this case splenectomy should be considered if platelet count is less than 10,000 – 20,000/mm3. Approx 50% of patient will achieve permanent remission.

Answer 34

C. More difficult to pre-oxygenate Also, much higher metabolic rate. FRC is the same (in mL/kg) as an adult. Alveolar ventilation is much higher in a neonate compared to an adult and this contributes to some of the increased metabolic rate (i.e. higher total work of breathing as a result of increased MV).

Answer 35

D. The same partial pressure as is obtained at 1 atmosphere (and 1/3 the concentration) • % concentration will decrease at increased atmospheric pressure but partial pressure will not change (i.e. if partial pressure output is 7.6mmHg (= 1%) at 1 atm, at 2 atm it will still be 7.6mmHg, but this now represents 0.5%) Desflurane vaporiser: • Delivers a constant % not a constant partial pressure • To deliver a constant partial pressure, the concentration dialled must be changed if atmospheric pressure changes Required dial setting = (usual dial setting (%) x 760)/Ambient partial pressure (mmHg) Eg: ambient pressure = 608mmHg and you need 10% Desflurane Required dial setting = (10 x 760)/608 = 12.5%

Answer 36

B. Right hydropneumothorax

Answer 37

C. Psychogenic polydipsia (hypotonic hyponatraemia due to excessive water intake; appropriate ADH suppression resulting in high output dilute urine) A and B incorrect - DI is associated with hypernatraemia - Central DI: reduced ADH secretion results in high output of poorly concentrated urine despite high serum Na and osmolality (correctable with DDAVP) - Nephrogenic DI: kidney insensitive to the effects of ADH (on V2 receptors), results in high output of poorly concentrated urine despite high serum Na and osmolality (not correctable with DDAVP) Cerebral salt wasting - hypotonic hyponatraemia, high urinary sodium, high urine osmolality. Often mistaken for SIADH which shares these characteristics. Distinguishing features are polyuria and hypovolaemia (neither of which are seen in SIADH) SIADH - diagnostic criteria: □ Hyponatraemia □ Hypo-osmolality (serum osm 100 (urine osm often > serum osm) □ Hypothyroidism and adrenal insufficiency excluded as causes □ No use of diuretics within a week of testing Causes: drugs, CNS, chest, malignancy

Answer 38

C. Primary hyperaldosteronism (Refractory hypertension, hypervolaeima, metabolic alkalosis, hypokalaemia, muscle weakness, nephrogenic DI, impaired glucose tolerance) Cushings - excess plasma cortisol; clinical features: moon face, truncal obesity, proximal myopathy, diabetes mellitus, OSA, LVH, HTN, high Na/HCO3/glucose, low K/Ca

Answer 39

? Mallampati score (I would go with this based on the paper below), ? pretracheal tissue volume Myatt J, Trends in Anaesthesia and Critical Care (2010) - Airway management in obese patients MP score: In the study by Juvin et al. a Mallampati score of 3 or 4 was the only independent risk factor for difficult intubation in obese patients with a specificity and positive predictive value of 62% and 29% respectively. This reflected the findings of another study of 100 morbidly obese patients (BMI > 40 kg/m2), where the product of the graded laryngoscopy view and number of intubation attempts was used to define difficult intubation. Mallampati score of 3 or 4 was also significantly associated with difficult tracheal intubation in the study by Gonzalez et al. Neck circumference: Neck circumference is generally measured at the level of the superior border of the cricoid cartilage. Large-neck circumference has been shown in several studies to be a predictor of difficult intubation in morbidly obese patients. In the study by Brodsky et al., a neck circumference of 40 cm was associated with a 5% probability of problematic intubation (described as grade of laryngoscopy view multiplied by intubation attempts ≥3), whereas at 60 cm, the probability was 35% (P = 0.02). Furthermore, a large-neck circumference was significantly associated with male gender (P

Answer 40

E. Bland-Altman plot (Describes the agreement between two measurement techniques; the means of corresponding measurements for the the two data sets are first calculated. Each of the samples is then represented on the graph by assigning the mean of the two measurements as the abscissa (x-axis) value, and the difference between the two values as the ordinate (y-axis) value.) Friedman's test - tests the null hypothesis that repeated measures or matched groups come from populations with the same median. Pearson's correlation - measure of strength of association

Answer 41

A. Auscultate the lungs

Answer 42

C. C7 Biceps brachii - C5/6 Triceps brachii - C7/8

Answer 43

B. 24 weeks (earliest gestation where fetal viability is possible, should you choose to act on information provided by the monitor and arrange urgent delivery)

Answer 44

B. Adenosine

Answer 45

D. Patient's wishes have been considered Where the death of the patient is reportable to the Coroner, the investigating Police, forensic pathologist and State Coroner should be contacted pre-mortem by the organ donor coordinator to seek advice as to the appropriateness for post-mortem organ donation, seek the Coroner’s consent, and to arrange the logistics of post-mortem notification and confirmation of donation approval.  All potential DCD donors should be referred to the Organ Donor Coordinator for evaluation of suitability for donation and audit. This is in line with current practice for organ donation.

Answer 46

A. C1-esterase inhibitor deficiency RCH website: Hereditary angioedema (HAE) causes recurrent episodes of angioedema in the upper respiratory, gastrointestinal tract or in subcutaneous tissues. Acute episodes of angioedema may be triggered by infection, stress, menstruation, surgery, dental work, trauma and some medicines (including oestrogen-containing contraceptives and ACE-inhibitors) or may have no clear trigger. HAE is a rare autosomal dominant condition in which C1 esterase inhibitor levels are reduced (HAE type I) or poorly functional (HAE type II). HAE is diagnosed by the finding of low C1 esterase inhibitor level or function. C4 level is also low during episodes of angioedema. Clinical features include: • Angioedema without pruritis and without urticaria (hives) • Abdominal pain (+/- nausea/vomiting) due to intestinal oedema • Laryngeal oedema Angioedema episodes usually take several hours to develop, and if untreated last 1-5 days. Antihistamines and corticosteroids have no role in the management of HAE related angioedema. The role of adrenaline in the treatment of HAE is not well established. There are anecdotal reports of efficacy using nebulised or intramuscular adrenaline to treat upper airway angioedema, however C1 esterase inhibitor is the treatment of choice for airway angioedema caused by HAE.

Answer 47

E. Rhabdomyolysis

Answer 48

E. Reduce sevoflurane

Answer 49

A. Amitriptyline Acute Pain Management - Scientific Evidence (2010) Amitriptyline and tramadol provided good control of phantom limb and stump pain in amputees (level II) Perioperative gabapentin was ineffective in reducing incidence and severity of phantom limb pain (level II) ---------------------------------------------- All of the listed drugs except gabapentin have serotonergic effects, so care will need to be taken with her concurrent paroxetine use.

Answer 50

D. Using the FLACC scale (behavioural pain assessment tool for 2-7 year-olds) FLACC - face, legs, activity, cry, consolability (score 0-2 for each) Wong-Baker Faces scale is a self-report pain assessment tool for 4-12 year-olds. Sims and Johnson: 3 different types of pain assessment tools: - Self-report (preferred, but only suitable for children older than 3-4 years who are able to self-report) - Behavioural - Physiological (poor specificity) Any assessment tool you use in clinical practice should be developmentally appropriate, sensitive, specific and validated for the population to which your patient belongs. Remember also that children may regress to an earlier developmental stage when sick or stressed.

Answer 51

D. 30 hours CEACCP - Transdermal drug delivery in pain management (2011) Estimated 30 h for plasma concentration to decrease by 50% after patch removal.

Answer 52

E. Absence of breathing

Answer 53

A. Increased intracellular gene expression APM - scientific evidence (2010): The intracellular changes associated with sensitisation may also activate a number of transcription factors both in DRG and dorsal horn neurons, with resultant changes in gene and protein expression (Ji et al, 2009).

Answer 54

B. CT chest (emedicine): CT scan of the chest and mediastinum • CT has become a routine part of the diagnostic evaluation of mediastinal tumors, cysts, and other masses. • CT is the test of choice for mediastinal masses. This test can greatly assist in determining the exact location of the mediastinal tumor and its relationship to adjacent structures. It also is useful in differentiating masses that originate in the mediastinum from those that encroach upon the mediastinum from the lung or other structures. It also detects pulmonary and mediastinal metastasis and differentiates from mediastinal fatty masses. • The CT scan is very useful in differentiating tissue densities. This assists greatly in distinguishing structures that are cystic or vascular from those that are solid. • CT scanning can reveal evidence of local invasion of adjacent structures by a mass or the presence of intrathoracic metastases. Magnetic resonance imaging • MRI is not routinely used to investigate germ cell neoplasms. MRI is more useful than CT to determine mediastinal invasion and involvement of the brachial plexus, diaphragm, or neural foramen, but this information is rarely useful from a clinical perspective. • MRI offers direct multiplanar imaging. It can be used when iodinated contrast cannot be administered. It provides increased detail in the subcarinal and aortopulmonary window areas, as well as the inferior aspects of the mediastinum at the level of the diaphragm. • MRI is more useful than the CT scan in the evaluation of invasion or extension of tumors, especially tumors closely associated with the heart. MRI is superior to the CT scan for the evaluation of masses located at the thoracic inlet or at the thoracoabdominal level. CT is superior in detecting pulmonary metastasis, spacial relationship to other mediastinal structures, and bony destruction. Echocardiography and ultrasonography • Ultrasonographic methods have been used to differentiate solid from cystic mediastinal masses and to assist in determining a connection between a mass and adjacent structures. These studies are more useful in the evaluation of masses associated with the heart and in vascular abnormalities. • In general, given the accuracy and detail provided by CT scan, MRI, and selected radionuclide scans, ultrasound techniques generally are not used as primary tools in the evaluation of mediastinal tumors and cysts. Positron emission tomography • Positron emission tomography (PET) has been studied extensively for the evaluation of a number of neoplasms, such as lung, colorectal, breast, lymphoma, and melanoma. • Its use in the evaluation of mediastinal tumors is being evaluated. It has been reported to be useful with thymic neuroendocrine tumors.

Answer 55

4.0-6.7% CHA2DS2-VAS CHF, HTN, age >/= 75 (2 pts), diabetes, stroke (2 pts), vascular disease, age 65-74, sex (female) 2-3 risk factors - 2.2-3.2% annual risk (moderate risk) 4-5 risk factors - 4.0-6.7% annual risk (high risk) 6 or more risk factors - 9.8% annual risk (very high risk) Anyone scoring 2 or more should be anticoagulated for stroke prevention.

Answer 56

E. Ventilate in the prone position

Answer 57

C. 6-8 days

Answer 58

B. The electrical fuse will immediately break and disconnect the device from the power supply. CEACCP - Electrical safety in the operating theatres (2003): Any conducting part of Class I equipment accessible to the user, such as the metal casing, is connected to earth by an earth wire. This wire becomes the third pin of the plug connecting the equipment to the mains socket. If a fault occurs which allows the live supply to come into contact with an accessible part, current flows down the earth wire. This new circuit has a lower resistance, resulting in an increased current which melts the protective fuses and breaks the circuit, removing the source of potential electrocution. In addition to the fuse in the mains socket, Class I equipment should have fuses at the equipment end of the mains supply lead, in both the live and neutral conductors so that this protection is operative even if the equipment is connected to an incorrectly wired socket outlet. From RCH Electrical Safety site: Class I equipment is fitted with a three core mains cable containing a protective earth wire. Exposed metal parts on class I equipment are connected to this earth wire. Should a fault develop inside the equipment and the exposed metal comes into contact with the mains, the earthing conductor will conduct the fault current to ground. Regular testing procedures ensure that earthing conductors are intact, as the integrity of the earth wire is of vital importance. RCD's (safety switches) are used in patient treatment areas to monitor and protect the mains supply. RCD's sense leakage currents flowing to earth from the equipment. If a significant leakage current flows, the RCD will detect it and shut off the power supplied to the equipment within 40 milliseconds. Hospital RCD's are more sensitive than those fitted in homes. A hospital RCD will trip at 10 milliamperes leakage current. Power outlets supplied through an RCD have a 'Supply Available' lamp. The lamp will extinguish when the RCD trips due to excessive leakage current.

Answer 59

D. Give 2 rescue breaths before commencement of CPR (false)

Answer 60

? B. best answer Drug reaction time is similar to peripheral IV route. Because the intramedullary vessel of the marrow space empties directly into the large central venous system, the onset times of medications administered via the IO route are comparable to those administered IV. There may be a somewhat prolonged duration of action of various medications with IO administration suggesting that the marrow cavity may act as a depot. (Intraosseous Infusions: A Review for the Anesthesiologist with a Focus on Pediatric Use Anaesthesia & analgesia 2010) Research studies have shown that medications administered through the proximal humerus via the intraosseous (IO) route, reach the heart at the same rate as drugs given through a central line – even during cardiac arrest. (EZ-IO website) A. False - IOs should be sited in the proximal medial tibia C. False - 13-gauge Kormed/Jamshidi (American Pharmaseal Laboratories, Glendale, CA) disposable bone marrow aspiration needle was the easiest to insert, did not become plugged with tissue during insertion, and was placed successfully on the first attempt. EZ-IO is 15G. Typically 15, 16,18G needles are used. D. False - bicarbonate does not damage bones but causes muscle necrosis if extravasation occurs E. False - Lung specimens from both upper and lower lobes were subsequently examined. Fat emboli (1–3 per high-power field) were found in approximately 30% of the lung samples with no statistically significant difference among the 4 groups. However, when evaluating changes in arterial blood gases to assess ventilation-perfusion relationships, there was no clinical effect noted related to the fat emboli. in a prospective nonrandomized trial that included 50 adults, fat embolism was not among the complications noted

Answer 61

A. Risk of uncontrolled haemorrhage Current Anaesthesia & Critical Care (2008) 19, 150–162 Indications for GA: - Overweight, difficult surgical access, additional procedure (prolonged procedure) All these studies report that EVAR under regional or local anaesthesia is feasible and effective, and none appears to show worse outcomes. However, no definitive evidence exists that they are superior techniques over general anaesthesia. The evidence supporting the use of regional or general anaesthesia for EVAR is lacking, most studies on this subject are descriptive in nature and should be interpreted with caution. The choice of anaesthesia will inevitably be tailored to the individual case. It is also worth bearing in mind that the technical success of EVAR does not appear to be related to the mode of anaesthesia.

Answer 62

E. Increased myocardial contractility (lack of depressant effect of general anaesthetic agent on the myocardium). Depending on where she sits on the Starling curve, both GA and neuraxial (with sympathetic blockade) will influence ejection fraction in the same direction as both will decrease preload and afterload.

Answer 63

A. Decreased urinary calcium While PTH increases the proportion of calcium reabsorbed in the distal nephron, the overall concentration of calcium appearing in the urine is often increased due to the increased filtered calcium load. Other actions of PTH: increased osteoclast activity (calcium and phosphate released from bone), increased renal phosphate excretion, increased vitamin D production.

Answer 64

C. Gas sample line leak!

Answer 65

A. Desflurane Sherman J, Anesth Analg (2012) - 'Life cycle greenhouse gas emissions of anesthetic drugs' BACKGROUND: Anesthesiologists must consider the entire life cycle of drugs in order to include environmental impacts into clinical decisions. In the present study we used life cycle assessment to examine the climate change impacts of 5 anesthetic drugs: sevoflurane, desflurane, isoflurane, nitrous oxide, and propofol. METHODS: A full cradle-to-grave approach was used, encompassing resource extraction, drug manufacturing, transport to health care facilities, drug delivery to the patient, and disposal or emission to the environment. At each stage of the life cycle, energy, material inputs, and emissions were considered, as well as use-specific impacts of each drug. The 4 inhalation anesthetics are greenhouse gases (GHGs), and so life cycle GHG emissions include waste anesthetic gases vented to the atmosphere and emissions (largely carbon dioxide) that arise from other life cycle stages. RESULTS: Desflurane accounts for the largest life cycle GHG impact among the anesthetic drugs considered here: 15 times that of isoflurane and 20 times that of sevoflurane on a per MAC-hour basis when administered in an O(2)/air admixture. GHG emissions increase significantly for all drugs when administered in an N(2)O/O(2) admixture. For all of the inhalation anesthetics, GHG impacts are dominated by uncontrolled emissions of waste anesthetic gases. GHG impacts of propofol are comparatively quite small, nearly 4 orders of magnitude lower than those of desflurane or nitrous oxide. Unlike the inhaled drugs, the GHG impacts of propofol primarily stem from the electricity required for the syringe pump and not from drug production or direct release to the environment. DISCUSSION: Our results reiterate previous published data on the GHG effects of these inhaled drugs, while providing a life cycle context. There are several practical environmental impact mitigation strategies. Desflurane and nitrous oxide should be restricted to cases where they may reduce morbidity and mortality over alternative drugs. Clinicians should avoid unnecessarily high fresh gas flow rates for all inhaled drugs. There are waste anesthetic gas capturing systems, and even in advance of reprocessed gas applications, strong consideration should be given to their use. From our results it appears likely that techniques other than inhalation anesthetics, such as total i.v. anesthesia, neuraxial, or peripheral nerve blocks, would be least harmful to the environment.

Answer 66

D. The provision of significant information Competence is independent of the provision of information (which is not reliant on the patient but on the person delivering the information)

Answer 67

A. Arrange for a cardiology follow-up and outpatient angiogram because he is at increased risk of future myocardial infarction.

Answer 68

E. Warfarin (St John's wort is an enzyme inducer - will increase metabolism of warfarin; also increases metabolism of clopidogrel but this results in more of the active component as clopidogrel is a pro-drug)

Answer 69

E. Reduce vascularity of thyroid gland

Answer 70

A. Inferior trunk (the medial cutaneous nerve of forearm arises from the medial cord, which originates from C8/T1 roots --> these roots converge to form the lower trunk)

Answer 71

B. Class 2

Answer 72

C. Maximal distance from radiation source CEACCP - Radiation safety for anaesthetists (2012) Intensity of radiation = 1/distance sqaured At least 3 feet from source 6 feet of air provides the same protection as 9 inches of concrete or 2.5mm lead ------------------------------------------------ Lead aprons do not stop all the x-rays. Typically at least a 80% reduction in radiation exposure is obtained by wearing a lead apron. It should be noted that the apron's effectiveness is reduced when more penetrating radiation is employed (e.g., the ABC boost's kVp for thick patients)

Answer 73

B. Isolated factor VII deficiency Consumer info: Prothrombinex-VF is used in patients who require reversal of anticoagulant therapy and for the prevention and treatment of bleeding in patients with low levels of factor II, IX or X. It is not recommended for the management of patients with isolated factor V or factor VII deficiency.

Answer 74

C. Peak velocity across aortic valve of 4.2 m/s Mild - 2.6-2.9 m/s Moderate - 3.0-4.0 m/s Severe - > 4.0 m/s

Answer 75

C. Normochromic anaemia occurs in over 85% of cases (false)

Answer 76

E. Muscle biopsy woman This is the only option that will give a definitive answer. Muscle biopsying her father would avoid an unnecessary general anaesthetic in a pregnant woman for what is basically elective surgery (although muscle biopsy could also be done under spinal anaesthetic). However, this would only be helpful if his biopsy turns out to be negative. If it is positive or equivocal, she will need to have one anyway. Also, there is a remote possibility of MH susceptibility being transmitted via her mother.

Answer 77

B. 50% PPV = (sens x prev)/([sens x prev] + [1 - spec][1 - prev])

Answer 78

D. The effect will last 5 days (false - lasts 12-24 hours; the response can also decrease with repeated doses because of the development of tachyphylaxis) Stoelting Desmopressin is a synthetic analogue of the antidiuretic hormone vasopressin that, when given intravenously, stimulates release of vWF from endothelial cells to produce an immediate rise in plasma vWF and factor VIII activity. Success in treating vWD patients with desmopressin depends on the disease type. Patients with type 1 vWD show the best response. The value of treatment with desmopressin in patients with type 2 disease is less certain. Patients with type 3 vWD do not respond to the drug since these patients lack endothelial stores of vWF. Desmopressin is available in both intravenous and intranasal preparations. Desmopressin is administered intravenously in a dose of 0.3 mcg/kg. Desmopressin therapy is most effective in treating mild bleeding episodes or in preventing bleeding during minor surgery. Patients with baseline vWF and factor VIII levels of more than 10 to 20 IU/dL seem to do best with this drug, demonstrating a threefold to fivefold increase in vWF levels. However, even if the response is suboptimal, bleeding may be partially contained, or, in the case of surgical prophylaxis, blood loss and the need for transfusion can be reduced.

Answer 79

B. Increased mortality BOOST 2 trial (NEJM, May 2013) A total of 2448 infants were recruited. Among the 1187 infants whose treatment used the revised oximeter-calibration algorithm, the rate of death was significantly higher in the lower-target group than in the higher-target group (23.1% vs. 15.9%; relative risk in the lower-target group, 1.45; 95% confidence interval [CI], 1.15 to 1.84; P=0.002). There was heterogeneity for mortality between the original algorithm and the revised algorithm (P=0.006) but not for other outcomes. In all 2448 infants, those in the lower-target group for oxygen saturation had a reduced rate of retinopathy of prematurity (10.6% vs. 13.5%; relative risk, 0.79; 95% CI, 0.63 to 1.00; P=0.045) and an increased rate of necrotizing enterocolitis (10.4% vs. 8.0%; relative risk, 1.31; 95% CI, 1.02 to 1.68; P=0.04). There were no significant between-group differences in rates of other outcomes or adverse events. 

Answer 80

A. Genitofemoral neuralgia

Answer 81

D. Patients with a Le Fort II fracture should have evaluation of the base of skull prior to nasal intubation Pure Le Fort fractures are uncommon in clinical practice, and most midfacial fractures are an amalgam of various types of Le Fort fractures. Pure Le Fort fractures occur in less than 50% of midfacial fractures.  Le Fort II and III fractures involve orbital wall fractures, and the eye must be completely evaluated. Intracranial injury must also be ruled out, and suspicion for CSF rhinorrhea should be high.

Answer 82

A. Advanced age

Answer 83

E. Adrenaline nebuliser 1:1000 0.5 mL/kg Sims and Johnson: Risk factors: - Small children - ETT too large (be wary if there is no leak from an uncuffed tube at 20 cmH2O and the procedure is going to be prolonged) - Cuffed ETT cuff pressure too high - Traumatic intubation - Movement of the ETT within the trachea during the procedure - Oedema at the level of the cricoid cartilage from the surgery or pre-existing conditions such as URTI Treatment: - Observation alone if no significant obstruction… otherwise: - IV dexamethasone 0.5-0.6 mg/kg up to max 12 mg - Nebulised adrenaline (1:1000 IV preparation - 0.5 mL/kg up to max of 5 mL - use undiluted in nebuliser bowl) - (Heliox… > 60% helium in oxygen) - but most kids won't tolerate the close fitting mask

Answer 84

D. Following complete resolution of motor blockade Stoelting Physiology and Pharmacology Transient Neurologic Symptoms Transient neurologic symptoms manifest as moderate to severe pain in the lower back, buttocks, and posterior thighs that appears within 6 to 36 hours after complete recovery from uneventful single-shot spinal anesthesia. Sensory and motor neurologic examination is not abnormal and relief of pain with trigger point injections and nonsteroidal anti-inflammatory drugs suggests a musculoskeletal component. In some patients, the pain is sufficiently intense to require treatment with opioids. Full recovery from transient neurologic symptoms usually occurs within 1 to 7 days. The incidence of transient neurologic symptoms is not altered by decreasing spinal lidocaine concentrations from 2% to 1% or 0.5% and are similar to the incidence of symptoms described with 5% lidocaine. Spinal anesthesia produced with 0.5% bupivacaine or 0.5% tetracaine is associated with a lower incidence of transient neurologic symptoms compared with lidocaine.