14 - surgery mcqs - 101 to 110

61. Hirschsprung's disease

a. Is due to absent ganglion cells in Auerbach's plexus

b. 10% cases have involvement of the recto-sigmoid segment

c. 10% cases present with delayed passage of meconium in the first 24 hours after birth

d. The affected segment of bowel appears dilated on barium enema

e. On rectal biopsy there increased acetylcholinesterase containing cells in the muscularis

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only a and e are true . 75 % cases involve the rectosigmoid . 10 % cases have total colonic involvement . 80% present with delayed passage of meconium . on barium enema the segment has a cone shaped contracted zone .

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62. Renal cell carcinoma

a. Arises from the distal convoluted tubule of the kidney

b. Presents with haematuria, loin pain and a mass in 10% of patients

c. Can present with polycythaemia

d. Spread occurs into renal vein and inferior vena cava in 10% patients

e. Should be treated with a nephrouretectomy

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b, c , d are true . renal cell carcinomas arise from the proximal tubule . polycythemia is due to the production of erythropoeitin . nephroureterectomy is done for renal transitional cell carcinoma . radical nephrectomy is done for renal cell carcinoma .

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63. Laparoscopic cholecystectomy

a. Is usually performed using a four port technique

b. The Veress needle is an 'open' technique for inducing the pneumoperitoneum

c. A supraumbilical abdominal scar is a contraindication to laparoscopic cholecystectomy

d. Dissection of Calot's triangle should be performed before the cystic duct is clipped

e. Most series report a conversion rate of over 20%

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a , c , d are true . veress needle is a closed technique of inducing the pneumoperitoneum . the hasson technique is the most commonly used open technique . conversion rates are now typically less than 5 %

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64. Regarding cardiovascular disease in the surgical patient

a. Following a myocardial infarct elective surgery should be deferred for over 6 months

b. 60% of post-operative re-infarctions are clinically silent

c. The mortality of a post-operative myocardial infarct is about 40%

d. The risk of a post-operative infarct is reduced in hypertensive patients

e. Left ventricular ejection fraction is a useful marker of cardiovascular function

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a , b , c , e are true . following a myocardial infarct is risk of post- operative reinfarction is 0 -3 months - 35 % , 3 - 6 months - 15 % , greater than 6 months - 4%

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65. The following cause a microcytic anaemia

a. B12 deficiency

b. Folate deficiency

c. Thalassaemia minor

d. Hypothyroidism

e. Iron deficiency

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only c and e cause microcytic anemia . all the remaining cause macrocytic anemia .

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66. In obstructive jaundice

a. Urinary conjugated bilirubin is increased

b. Serum unconjugated bilirubin is increased

c. Urinary urobilinogen is reduced

d. Serum conjugated bilirubin is reduced

e. Faecal stercobilinogen is reduced

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a , c , e are true . serum and urinary conjugated bilirubin is increased. both fetal stercobilinogen and urinary urobilinogen are reduced .

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67. The following are clinical features of a large pulmonary embolism

a. Pleuritic chest pain

b. Haemoptysis

c. High fever

d. Bradycardia

e. Collapsed neck veins

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only a and b are true . low grade pyrexia is seen . tachycardia and tachypnea are the usual features . neck veins are distended due to right heart dysfunction .

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68. In patients with a proven pulmonary embolus

a. Only 10% have clinical evidence of deep venous thrombosis

b. The classic ECG features are described S1Q3T3

c. Arterial blood gases are normal in 50% of patients

d. Low molecular weight heparins are as effective a heparin infusion

e. Thrombolysis should be considered if evidence of haemodynamic instability

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all are true .

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69. Regarding the anatomy of the inguinal canal

a. The internal ring lies midway between the symphysis pubis and anterior superior iliac spine

b. The internal ring lies medial to the inferior epigastric vessels

c. The external oblique aponeurosis forms the anterior boundary

d. The inguinal ligament forms the inferior boundary

e. The conjoint tendon forms the lateral part of the posterior wall

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a , c , d are true . internal ring lies lateral to the inferior epigastric vessels . the conjoint tendon forms the medial part of the posterior wall .

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70. The thyroid gland

a. Arises from the pharyngeal floor between the 1st and 2nd pharyngeal pouches

b. The isthmus lies at the level of the thyroid cartilage

c. The superior thyroid artery lies close to the external laryngeal nerve

d. The inferior thyroid artery arises from the costo-cervical trunk

e. The middle thyroid vein joins the external jugular artery

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only a and c are true . the thyroid isthmus lies at the level of the second and third tracheal rings . the inferior thyroid artery arises from the thyro - cevical trunk . the middle thyroid vein joins the internal jugular vein.

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