22 - surgery mcqs - 181 to 190

181. Regarding the use of laxatives

a. Ispaghula husk (e.g. Fybogel) is a bulk forming agent

b. Lactulose is a glucose polymer

c. Lactulose is hydrolysed by bacteria in the small intestine

d. Senna is a GI stimulant that acts within 30 minutes

e. Laxative abuse can lead to hypokalaemia and colonic atony

---------------------------------------------

only a and e are true . lactulose is a disaccaride of galactose and fructose . it is hydrolyzed by colonic bacteria . it is then fermented to acetic acid and lactic acid . senna is a GI stimulant but takes about 8 hours to act .

--------------------------------------------

182. Hepatocellular carcinoma

a. Has a high incidence in East Africa and South-east Asia

b. Its worldwide incidence parallels the prevalence of Hepatitis B

c. Mycotoxins (e.g. aflatoxin) are an important aetiological factor

d. Over 80% of tumours are surgically resectable

e. Liver transplantation offers the only chance of cure in those with irresectable disease

--------------------------------------------

a , b , c and e are true . cirrhosis , hep B and hep C are the most important risk factors . less than 25 % of the tumors are surgically resectable .

--------------------------------------------

183. Serum alpha fetoprotein

a. Is increased in testicular tumours

b. In testicular tumours is produced by trophoblastic elements

c. Is increased in over 70% patients with hepatocellular carcinoma

d. In patients with hepatocellular carcinoma levels correlate well with size of the tumour

e. In patients with hepatocellular carcinoma levels rise following resection of the tumour

-----------------------------------------------

a , c , d are true . in testicular tumors , alpha feto protein is produced by yolk sac elements . after surgery the AFP levels usually fall .

---------------------------------------------

184. Regarding testicular tumours

a. They are the commonest malignancy in young men

b. Peak incidence for teratomas is seen at the age of 50 years

c. Seminomas are radiosensitive

d. Over 75% of Stage I teratomas are cured by surgery alone

e. Chemotherapy rarely produces a cure in those with metastatic disease

---------------------------------------

a , c , d are true . peak incidence of teratomas 25 years and the seminomas 35 years . chemotherapy can produce a cure even in metastatic disease. teratomas are not radiosensitive .

----------------------------------------

185. In patients with ascites

a. A transudate has a protein content of greater than 30 g per litre

b. Both malignancy and infection result in a transudate

c. Ovarian carcinoma is the commonest malignant cause of ascites

d. Cirrhosis results in marked sodium retention

e. Tumour cells increase the permeability of the peritoneum

-------------------------

c , d , e are true . an exudate has a protein concentratin greater than 30 g per litre . malignancy and infection cause an exudate .

-------------------------------------

186. Duct ectasia

a. If often associated with both aerobic and anaerobic bacterial infection

b. The incidence is reduced in smokers

c. May present with a green or watery nipple discharge

d. May present with nipple inversion

e. Can be adequately treated with a microdochectomy

-------------------------------------------

a , c , d are tumors . incidence is increased in smokers . treatment often requires total duct excision . microdochectomy is excision of a single duct .

------------------------------------

187. Regarding opiate analgesia

a. Patient controlled analgesia (PCA) is more effective than intermittent parenteral dosing

b. The total opiate dose is usually reduced with a PCA

c. Fentanyl is more water soluble than morphine

d. Epidural morphine can result in late respiratory depression

e. Epidural and parenteral morphine can be safely administered together

-----------------------------------------

a , b , d are true . fentanyl is more lipid soluble than morphine . opiates via the epidural and parenteral route shud never be combined

------------------------------------

188. Regarding renal failure

a. Ureteric obstruction produces pre-renal renal failure

b. Pre-renal renal failure produces a high urinary sodium (>20 mmol/l)

c. Pre-renal renal failure produces a high urine osmolality (>500 mosm/kg)

d. Non-steroidal anti-inflammatory drugs increase glomerular blood flow

e. Patients with an increased creatinine are at increased risk of postoperative renal failure

--------------------------------

only c and e are true . pre-renal renal failure is usually due to hypovolemia . NSAID'S reduce GFR .

* In pre-renal failure
o Urine specific gravity - >1.016
o Low urinary sodium - <20>
o High urinary urea - >250 mmol/l
o High osmolality - > 500 mosm/kg
* In intrinsic renal failure
o Urine specific gravity - <1.010
o High urinary sodium - >40 mmol/l
o Low urinary urea - <185>
o Isotonic urine - 300-350 mosm/kg

--------------------------------------------

189. Regarding colonic polyps

a. Juvenile polyps are usually pre-malignant

b. Metaplastic polyps often exceed 2 cm in diameter

c. Metaplastic polyps are pre-malignant

d. Villous adenomas are more prone to malignant transformation than tubular adenomas

e. Approximately 10% of the population older than 45 years have asymptomatic polyps

---------------------------------------------

d and e are true . juvenile and metaplastic polyps are not pre-malignant .

---------------------------------------------------

190. Intussusception

a. Is most common in children from 6 to 12 years

b. Presents with colicky abdominal pain, rectal bleeding and an abdominal mass

c. 10% present with diarrhoea and vomiting suggestive of gastroenteritis

d. If no shock or peritonitis hydrostatic reduction can be attempted

e. A Meckel's diverticulum can induce an intussusception

-----------------------

only a is wrong . most common in children from 6 to 12 months .

----------------------------