2012.2 Flashcards

Question

Rpt: Hb 80 g/L with reticulocyte 10%: A. Hereditary spherocytosis

Answer 1

A. Hereditary spherocytosis | haemolytic anaemia due to intrinsic defect in red cell membrane proteins

Answer 2

B. Decreased BP with inspiration greater than normal

Answer 3

A. Optic ischaemia (ischaemic optic neuropathy)

Answer 4

D. Standford B (from radiopaedia.org) DeBakey classification The DeBakey classification divides dissections into: • type I: involves ascending and descending aorta (= Stanford A) • type II: involves ascending aorta only (= Stanford A) • type III: involves descending aorta only, commencing after the origin of the left subclavian artery (= Stanford B) Standford classification Along with the DeBakey classification, the Stanford classification is used to separate aortic dissections into those that need surgical repair, and those that usually require only medical management. The Stanford classification divides dissections by the most proximal involvement: * type A: A affects ascending aorta and arch * accounts for ~60% of aortic dissections * needs surgical management * may result in: * coronary artery occlusion * aortic incompetence * rupture into pericardial sac with resulting cardiac tamponade type B: B begins beyond brachiocephalic vessels • accounts for ~40% of aortic dissections • dissection commences distal to the left sub-clavian artery medical management with blood pressure control

Answer 5

A. Patent ventriculo-atrial shunt

Answer 6

A. 0-24 hours

Answer 7

A. Aortic regurgitation ``` Contraindications: - Absolute: ○ Aortic regurgitation ○ Aortic dissection ○ Aortic stents - Relative: ○ Uncontrolled sepsis ○ AAA ○ Severe PVD ○ Major arterial reconstruction surgery ```

Answer 8

A. Increased myocardial work

Answer 9

A. Dorsal column

Answer 10

A. 8 E2, V2, M4

Answer 11

A. Decreased constipation | probably decreased risk of intravenous misuse, but marketed for decreased constipation

Answer 12

A. Arterial pulse contour analysis

Answer 13

A. Lower Hb threshold for transfusion

Answer 14

A. 7 days | Although other sources say 48 h if CrCl > 80 mL/min or 96 h if CrCl 30-50 mL/min

Answer 15

A. Day 5 at 12 midday (Wait 12 hours, so 8am at the earliest. If you turn the infusion off at 8am and then leave it in another 4 hours you'll have a chance to assess analgesia without the epidural before you take it out)

Answer 16

A. Indomethacin

Answer 17

B. 4 g | 8 mL 50%

Answer 18

A. Ruptured diaphragm

Answer 19

E. Lithotripsy Prophylactic antibiotics should be given for dental procedures that involve manipulation of gingival tissue or the periapical region of teeth or perforation of the oral mucosa (e.g. extraction, root canal, replacing avulsed teeth)

Answer 20

Modified Parkland: 3 x weight x % burn = 3 x 20 x 15 = 900 mL over 24 h 450 mL in first 8 hours 2 hours left to give 450 mL, so 225 mL/h ...+ maintenance (= 60 mL/h) = 285 mL in first hour

Answer 21

B. Continue with careful monitoring (and an ETT)

Answer 22

B. No change in QT interval in response to a Valsalva manoeuvre Long QT syndrome and anaesthesia (BJA 2003) Preoperatively, all patients with known LQTS should be on maintenance β‐blocker therapy, which must be continued up to and including the day of surgery. Preoperative assessment of its adequacy should determine that the heart rate does not exceed 130 min–1 during exercise; where exercise testing is impractical, there should ideally be no change in the QT interval in response to a Valsalva manoeuvre in a fully β‐blocked individual... ...Positive pressure ventilation strategies should ensure that sustained high intrathoracic pressures are avoided, as this mimics a Valsalva manoeuvre, which can prolong the QT interval in patients who are not completely β‐blocked.

Answer 23

B. May cause bradycardia

Answer 24

E. Proceed with a magnet handy If the patient is not pacemaker-dependent, no need to reprogram to asynchronous mode. Just have a magnet handy (which should switch the PPM to asynchronous mode, although this is not 100% reliable) in the event that EMI causes inappropriate sensing.

Answer 25

C. Impaired HPV Anesthetic Challenges in Patients After Lung Transplantation Airway reactivity does not appear to be increased. Mucociliary clearance is impaired in pulmonary allograft, which together with immunosuppression and impaired cough, place the patient at an increased risk for perioperative pneumonia. Meticulous hygiene and sterile techniques can reduce exposure of these immune-compromised patients to infectious organisms. Antibiotics should continue during the time of the operation, as should the application of immunosuppressive medications. Stress doses of steroids will be required in most cases. Hypoxic pulmonary vasoconstriction is intact in the pulmonary allograft so during an episode of rejection, pulmonary blood flow may be directed away from the transplanted lung. In patients with SLT, 60% to 70% of pulmonary perfusion is directed toward the transplanted lung.

Answer 26

Posterior cord of the brachial plexus

Answer 27

A. Medial antebrachial cutaneous nerve

Answer 28

1-3% CEACCP - Fat embolism (2007) The majority (95%) of cases occur after major trauma. Fat embolism syndrome is a serious consequence of fat emboli producing a distinct pattern of clinical symptoms and signs. It is most commonly associated with fractures of long bones and the pelvis, and is more frequent in closed, rather than open, fractures. The incidence increases with the number of fractures involved. Thus, patients with a single long bone fracture have a 1–3% chance of developing the syndrome, but it has been reported in up to 33% of patients with bilateral femoral fractures.

Answer 29

C. Normal saline

Answer 30

C. Milrinone

Answer 31

Loading dose = 20 mg/kg Dose for neonates 10kg, dose is 15mg/kg

Answer 32

Fall in SpO2

Answer 33

A. Sedation

Answer 34

A. Metabolised by plasm cholinesterase. False - metabolised by red cell and tissue esterases

Answer 35

C. Different concentration Off-label use is the use of pharmaceutical drugs for an unapproved indication or in an unapproved age group, unapproved dosage, or unapproved form of administration.

Answer 36

B. Can be used to calculate the CO

Answer 37

D. Mostly venous saturation and some arterial saturation Cerebral oximetry differs from pulse oximetry in that tissue sampling represents primarily (70-75%) venous, and less (20-25%) arterial blood. Cerebral oximetric monitoring is also not dependent upon pulsatile flow.

Answer 38

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

Answer 39

E. Elevated PaCO2 | Ventilatory function preserved

Answer 40

B. Incompatible transfusion

Answer 41

A. High NPV

Answer 42

B. Arterial line Contraindications to magnetic resonance imaging (T Dill, Heart 2008; 94:943–948) Pulmonary artery monitoring catheters and temporary transvenous pacing leads contain non-ferromagnetic but electrically conductive material. During an MRI examination radiofrequency pulses might induce currents that could lead to thermal injuries. Therefore, it is a contraindication to examine patients with such catheters by MRI.

Answer 43

A. Subcostal nerve

Answer 44

C. Acidic urine Boys > girls Peak incidence 2-8 weeks Most K loss is via renal tract Pathophysiology of acid-base/electrolyte changes in pyloric stenosis Three stages: ○ Hypochloraemic, hyponatraemic metabolic alkalosis with dehydration and alkaline urine - Gastric outlet obstruction causes loss of hydrogen chloride, water, and small amounts of sodium and potassium; bicarb formed during the production of hydrogen chloride enters the plasma, causing metabolic alkalosis - This excess bicarb appears in the urine (freely filtered but not all reabsorbed) ○ Potassium depletion with paradoxical acidic urine - Dehydration and reduced ECF volume stimulates aldosterone secretion, and sodium reabsorption in the distal tubule in exchange for potassium - this causes a significant kaliuresis and depletion of total body potassium (most potassium loss in pyloric stenosis occurs in the urine) - Because potassium is an intracellular ion, plasma potassium is a poor guide and is usually normal - In the setting of severe dehydration, the kidney is forced to defend ECF volume in preference to pH, and sodium reabsorption in the renal tubule is maximised by exchanging for H+. There is now H+ secreted in the urine, resulting in a paradoxical aciduria that makes the metabolic alkalosis even worse. ○ Shock, lactic acidosis and starvation ketosis If treatment is delayed, hypovolaemic shock and lactic acidosis develop (which is superimposed on the metabolic alkalosis)

Answer 45

A. Less sensitive, more specific

Answer 46

??? A. Systematic review author bias This is potentially a problem, although there are strict protocols that generally have to be adhered to in conducting a systematic review, which should hopefully exclude author bias.

Answer 47

A. Haemodynamically stable

Answer 48

A. Start ACEi

Answer 49

D. Uteroplacental insufficiency Early decels - head compression Variable decels - cord compression Early decelerations are usually benign and associated with the sleep cycle and often in the range of 4-8 cm of cervical dilatation. They are caused by head compression and in general are a normal physiological response to a mild increase in intracranial pressure. Importantly they are uniform in shape and start and finish with the contraction. They may be said to mirror the contraction. Variable decelerations are a repetitive or intermittent decreasing of FHR with rapid onset and recovery. Time relationships with contraction cycle may be variable but most commonly occur simultaneously with contractions. The significance of variable decelerations depends on the overall clinical picture and specific features of the decelerations themselves, as well as other features of the CTG. Variable decelerations in association with other non-reassuring or abnormal features change the category of the deceleration to ‘complicated’. Complicated variable decelerations are defined by their features as well as the other features of the CTG. These additional features indicate the likelihood of fetal hypoxia and the definition includes one or more of the following: - Rising baseline rate or fetal tachycardia - Reduced or absent baseline variability - Slow return to baseline FHR after the end of the contraction - Onset of the nadir after the peak of the contraction - Large amplitude (by 60bpm or to 60bpm) and /or long duration (60 seconds) - Loss of pre- and post-deceleration shouldering (abrupt brief increases in FHR baseline) - Presence of post deceleration smooth overshoots (temporary increase in FHR above baseline) Prolonged decelerations are defined as a decrease of FHR below the baseline of more than 15 bpm for longer than 90 seconds but less than 5 minutes. Late decelerations are defined as uniform, repetitive decreasing of FHR with, usually, slow onset mid to end of the contraction and nadir more than 20 seconds after the peak of the contraction and ending after the contraction. Late decelerations are caused by contractions in the presence of hypoxia. This means that they will occur with each contraction and the fetus is already hypoxic. There will be no features of a well oxygenated fetus, like early or typical variable decelerations, normal baseline variability or shouldering. They start after the start of the contraction and the bottom of the deceleration is more than 20 seconds after the peak of the contraction. Importantly, they return to the baseline after the contraction has finished. In the hypoxic fetus, this will include decelerations of less than 15bpm (and occasionally less than 5bpm).

Answer 50

A. Medial cord | or probably actually lower trunk at that level

Answer 51

A. False positive rate 1%

Answer 52

A. SVR x BSA

Answer 53

A. Glossoptosis

Answer 54

A. Loss of Q waves in V5-6 LITFL: * Normally the septum is activated from left to right, producing small Q waves in the lateral leads. * In LBBB, the normal direction of septal depolarisation is reversed (becomes right to left), as the impulse spreads first to the RV via the right bundle branch and then to the LV via the septum. * This sequence of activation extends the QRS duration to > 120 ms and eliminates the normal septal Q waves in the lateral leads. * The overall direction of depolarisation (from right to left) produces tall R waves in the lateral leads (I, V5-6) and deep S waves in the right precordial leads (V1-3), and usually leads to left axis deviation. * As the ventricles are activated sequentially (right, then left) rather than simultaneously, this produces a broad or notched (‘M’-shaped) R wave in the lateral leads. 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 55

A. Sedation score

Answer 56

A. Underappreciated degree of blood loss

Answer 57

A. Nothing will happen

Answer 58

A. IV magnesium

Answer 59

A. Pulmonary valve

Answer 60

A. Distal to left subclavian artery

Answer 61

A. Tricuspid valve

Answer 62

A. Pseudomonas

Answer 63

A. Sex | although CHA2DS2-VAS score has sex as the second 'S'

Answer 64

A. 960 mg | 16 mg/kg

Answer 65

A. Secondary hyperparathyroidism

Answer 66

A. Add/start antihypertensive

Answer 67

A. Hypernatraemia, hypokalaemia, normoglycaemia

Answer 68

A. 32% 1/2 upper limb = 4.5 Anterior abdomen = 9 Whole lower limb = 18 Total = 31.5

Answer 69

E. S3 Truffier's line crosses the midline of the vertebral column at the L4-5 or L5-S1 interspace, well below the termination of the spinal cord making this landmark applicable in all pediatric patients. The dural sac in neonates and infants also terminates in a more caudad location compared to adults, usually at about the level of S3 compared to the adult level of S1.

Answer 70

B. Increase inhaled sevoflurane concentration after removing LMA

Answer 71

A. 6 hours

Answer 72

B. Cardiac laceration ?? --> possible, but probably the least common complication of the ones listed

Answer 73

A. 4/6 loudness

Answer 74

C. 32-34 C

Answer 75

C. PND Asymptomatic patients, even with critical aortic stenosis, have an excellent prognosis for survival, with an expected death rate of less than 1% per year; only 4% of sudden cardiac deaths in severe aortic stenosis occur in asymptomatic patients. Among symptomatic patients with medically treated, moderate-to-severe aortic stenosis, mortality rates from the onset of symptoms are approximately 25% at 1 year and 50% at 2 years. More than 50% of deaths are sudden. In patients in whom the aortic valve obstruction remains unrelieved, the onset of symptoms predicts a poor outcome with medical therapy; the approximate time interval from the onset of symptoms to death is 1.5-2 years for heart failure, 3 years for syncope, and 5 years for angina.

Answer 76

A. Prolonged labour

Answer 77

A. Adductor pollicis

Answer 78

C. Sevo~Iso > Des > N2O Fat:blood coefficients - N2O: 2.3 - Des: 27 - Iso: 45 - Sevo: 48

Answer 79

A. Adenosine 100 mcg/kg

Answer 80

A. Muscle rigidity

Answer 81

A. Hypertonic saline

Answer 82

A. Guillain-Barre Guillain–Barré syndrome (GBS), sometimes Landry's paralysis or Guillain–Barré–Strohl syndrome, is an acute polyneuropathy, a disorder affecting the peripheral nervous system. Ascending paralysis, weakness beginning in the feet and hands and migrating towards the trunk, is the most typical symptom, and some subtypes cause change in sensation or pain, as well as dysfunction of the autonomic nervous system. It can cause life-threatening complications, in particular if the respiratory muscles are affected or if the autonomic nervous system is involved. The disease is usually triggered by an infection.

Answer 83

A. Aspirin

Answer 84

A. An unexpected drop in ETagent

Answer 85

A. Resistance x compliance

Answer 86

A. Low ferritin, low serum iron

Answer 87

A. Flaccid paralysis

Answer 88

B. Clonidine E. Midazolam (neither contraindicated)

Answer 89

A. 1 mg/kg propofol

Answer 90

B. Procainamide

Answer 91

C. Lingual nerve Tongue: anterior two thirds – general sensation provided by lingual branch of V3 (taste from chorda tympani branch of VII); posterior third – general sensation and taste both provided by glossopharyngeal nerve (IX) The lingual nerve is a branch of the mandibular nerve, which in turn is a branch of the trigeminal nerve, and it is this nerve that supplies sensory innervation to the anterior two thirds of the tongue. The chorda tympani branch of the facial nerve, which supplies taste sensation to the anterior two thirds of the tongue, also runs with the lingual nerve. The lingual nerve passes between the lateral and medial pterygoid muscles then passes the ramus of the mandible before crossing obliquely to the side of the tongue and passing medially to the inferior surface of the tongue base and the medial aspect of the mandible close to the third molar. The most likely mechanism of lingual nerve injury is mechanical compression between the shaft of the LMA and the lower incisors or excessive cuff pressure.

Answer 92

B. May be performed supine or prone Entry point is the groove between biceps femoris tendon and vastus lateralis. A popliteal sciatic block alone would not be sufficient for ankle surgery (need saphenous as well). As effective as posterior (proximal) sciatic nerve block for surgery below the knee. Inversion/plantar flexion: tibial nerve Eversion: superficial peroneal nerve Dorsiflexion: deep peroneal nerve

Answer 93

Patient factors - Extremes of body habitus (thin, obese) - Old age - Male sex - History of vascular disease, diabetes, smoking - Coagulopathy, or presence of haematoma near nerve - Infection/abscess near nerve - Pre-existing generalised neuropathy - Hereditary predisposition - Structural anomaly/congenital abnormality (e.g. constriction at thoracic outlet or condylar groove, arthritic narrowing of joint space) Surgical factors - Neurosurgery, cardiothoracic surgery, general surgery, orthopaedic surgery - Use of tourniquets and tight fitting casts - Rib retraction (e.g. in thoracic and cardiac surgery - may stretch brachial plexus) - Pneumonectomy, axillary lymph node dissection --> can stretch long thoracic nerve (motor deficit of serratus anterior muscle, disrupted scapula movement) - Long hospital stay Anaesthetic factors and positioning - Direct needle damage during regional anaesthesia; LA can directly cause nerve toxicity (esp. high concentration LAs) - Inadequate padding - Poor positioning - Perioperative hypotension, hypovolaemia - Hypothermia (high incidence of nerve injury after induced hypothermia)

Answer 94

A. Cerebral salt wasting B. SIADH (either could be correct, depending on volume status and urine output) SIADH - Diagnostic criteria: □ Hyponatraemia □ Hypo-osmolality (serum osm 20 mmol/L, urine 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 Cerebral salt wasting syndrome can be mistaken for SIADH as the biochemical picture is similar. Like SIADH it results in a hypotonic hyponatraemia, high urinary sodium, and high urine osmolality. The distinguishing features are that in CSWS the patient is hypovolaemic, with polyuria. It is rare and typically associated with recent intracranial surgery. The process is usually self-limiting and treated with isotonic saline.

Answer 95

C. Prothrombinex and FFP Warfarin reversal Prothrombinex-VF, a three-factor PCC, is the only product currently in routine use in Australia and New Zealand for warfarin reversal. Due to its low levels of factor VII, the Warfarin Reversal Consensus Guidelines published in 2004 recommended that it be supplemented with FFP. Prothrombinex-VF is able to completely reverse an excessive INR within 15 minutes, but the infused clotting factors have half-lives similar to endogenous clotting factors. Therefore, vitamin K 5–10 mg should be given intravenously with the PCC to sustain the reversal effect. The intravenous route achieves a more rapid response compared with oral administration, with an onset of action seen within 6–8 hours. However, both routes achieve a similar correction of INR by 24 hours.

Answer 96

A. Increased investigations for neonatal sepsis

Answer 97

A. Standardize description of physical status

Answer 98

A. Four times

Answer 99

B. (Effervescent) ranitidine

Answer 100

A. Most likely to get gas embolism at initial CO2 insufflation

Answer 101

A. Adrenaline

Answer 102

A. Pulmonary hypertension

Answer 103

A. Auriculotemporal nerve (branch of mandibular nerve) | posterior third supplied by lesser occipital nerve from C2

Answer 104

A. Transtentorial herniation

Answer 105

A. Neostigmine will reverse

Answer 106

A. Muscle rigidity