i) It can be confirmed by checking for a pulse FALSE
ii) 3mg of atropine should be administered every 3 minutes FALSE
iii) Tension pneumothorax may be the cause of the arrest TRUE
iv) Three monophasic shocks of 200J, 200J nd 360J should be administered FALSE
v) asystole appears on the monitor as a completely flat line FALSE
Explanations
i) Reagarding asystolic arrest: It can be confirmed by checking for a pulse (FALSE)
there are four checks needed to confirm asystole including: pulse check, check the leads on the patients chest and the monitor, check the gain on the monitor and cycle through the leads
ii) Reagarding asystolic arrest: 3mg of atropine should be administered every 3 minutes (FALSE)
3mg of atropine is a consider drug in asystole but, if administered, it is given as a single dose
iii) Reagarding asystolic arrest: Tension pneumothorax may be the cause of the arrest (TRUE)
In cardiac arrest consider the four H's and four T's for possible causes: hypoxia, hypothermia, hypo/hyperkalaemia (metabolic disturbance), hypovoleamia, tension pneumothorax, tamponade, thrombo-embolic disorders, toxic/therapeutic
iv) Reagarding asystolic arrest: Three monophasic shocks of 200J, 200J nd 360J should be administered (FALSE)
defibrillation is essential in the management of VF/pulseless VT, asystole is on the non-shockable side of the ALS algorithm
v) Reagarding asystolic arrest: asystole appears on the monitor as a completely flat line (FALSE)
if you have a completelty flat line do the asystole checks. There should still be some baseline activity.
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22. Regarding symptomatic pre-eclampsia
i) It may develop from 12 weeks gestation FALSE
ii) Diuresis is a prodromal symptom prior to a fit FALSE
iii) Hyporeflexia is a recognised sign. FALSE
iv) The circulating blood volume is decreased. TRUE
v) Diazepam is the treatment of choice for imminent eclampsia. FALSE
Explanations
i) Regarding symptomatic pre-eclampsia It may develop from 12 weeks gestation (FALSE)
May develop from 20 weeks onwards.
ii) Regarding symptomatic pre-eclampsia Diuresis is a prodromal symptom prior to a fit (FALSE)
The prodromal period is characterised by oliguria as the circulating volume is reduced.
iii) Regarding symptomatic pre-eclampsia Hyporeflexia is a recognised sign. (FALSE)
HYPERreflexia is a pre-eclamptic sign and if present requires close monitoring and prevention of subsequent fits.
iv) Regarding symptomatic pre-eclampsia The circulating blood volume is decreased. (TRUE)
This is due to numerous factors including: hypoproteinaemic induced oedema and decreased aldosterone secretion.
v) Regarding symptomatic pre-eclampsia Diazepam is the treatment of choice for imminent eclampsia. (FALSE)
Magnesium sulphate has been shown to be more effective. It is given as a loading dose with subsequent maintanence by continuous infusion. Monitor reflexes and urine output, look for signs of Mg+ toxicity.
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23.Features of hypercalcaemia include:
i) Constipation TRUE
ii) Tetany FALSE
iii) Polyuria and polydipsia TRUE
iv) Increased incidence of gall stones FALSE
v) Headache TRUE
Explanations
i) Features of hypercalcaemia include: Constipation (TRUE)
Constipation does occur
ii) Features of hypercalcaemia include: Tetany (FALSE)
This is a feature of hypocalcaemia
iii) Features of hypercalcaemia include: Polyuria and polydipsia (TRUE)
Polyuria and polydipsia occur as the kideny tries to excrete calcium.
iv) Features of hypercalcaemia include: Increased incidence of gall stones (FALSE)
Hypercalcaemia results in an increased incidence in ureteric stones, not gall stones.
v) Features of hypercalcaemia include: Headache (TRUE)
Headache is a feature of hypercalcaemia
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24. The following statements about skin conditions are true
i) Mycosis fungoides is caused by a dermatophyte infection FALSE
ii) Impetigo is caused by staph.epidermis FALSE
iii) Lupus vulgaris is found on the head and neck in over 85% of cases TRUE
iv) Psoriasis arthropathy affects under 15% of people with psoriasis in the UK TRUE
v) In the UK population, pemphigus is less common than bullous pemphigoid TRUE
Explanations
i) The following statements about skin conditions are true Mycosis fungoides is caused by a dermatophyte infection (FALSE)
Despite the misleading name, this is a cutaneous T-cell lymphoma
ii) The following statements about skin conditions are true Impetigo is caused by staph.epidermis (FALSE)
Impetigo is caused by staph. aureus infection
iii) The following statements about skin conditions are true Lupus vulgaris is found on the head and neck in over 85% of cases (TRUE)
Lupus vulgaris is rarely found elsewhere
iv) The following statements about skin conditions are true Psoriasis arthropathy affects under 15% of people with psoriasis in the UK (TRUE)
The majority of people with psoriasis in the UK are not affected by the associated arthropathy
v) The following statements about skin conditions are true In the UK population, pemphigus is less common than bullous pemphigoid (TRUE)
Pemphigus is a severe disease, causing intraepidermal blistering. Bullous pemphigoid occurs at the dermo–epidermal junction.
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25.Regarding Grave's Disease:
i) There is approximately equal prevalance between the two sexes. FALSE
ii) There is a characteristic atrophy and reduction in size of the thyroid gland. FALSE
iii) It is an autoimmune thyroid disease. TRUE
iv) It is characteristically associated with hypothyroidism FALSE
v) It is a more common in areas where there is a general iodine-deficieny in the diet. FALSE
Explanations
i) Regarding Grave's Disease: There is approximately equal prevalance between the two sexes. (FALSE)
Female:Male - 9:1.
ii) Regarding Grave's Disease: There is a characteristic atrophy and reduction in size of the thyroid gland. (FALSE)
Totally the opposite occurs. It increases in size to form a goitre due to epithelial proliferation, increase in stromal vascularity, and lymphoctyic infiltration.
iii) Regarding Grave's Disease: It is an autoimmune thyroid disease. (TRUE)
Autoantibodies are produced and are directed against the TSH receptor on the thyroid membrane.
iv) Regarding Grave's Disease: It is characteristically associated with hypothyroidism (FALSE)
Grave's disease is typically associated with hyperthyroidism. Antibodies are directed against the TSH receptor on the thyroid membrane. The binding of the antibody stimulates the receptor in a similar way to TSH and therefore increases thyroid hormone production via up-regulation of the adenyl cyclase-cAMP system.
v) Regarding Grave's Disease: It is a more common in areas where there is a general iodine-deficieny in the diet. (FALSE)
Iodine deficiency does not predispose to Grave's Disease.
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26. Acute renal failure:
i) Causes hypocalcaemia TRUE
ii) Causes a metabolic alkalosis FALSE
iii) Total body potassium can be reduced by administration of an insulin dextrose infusion FALSE
iv) Intravenous calcium chloride is indicated in the treatment of hyperkalaemia TRUE
v) Calcium resonium can be used to lower total body potassium but works slowly TRUE
Explanations
i) Acute renal failure: Causes hypocalcaemia (TRUE)
Hypocalcaemia is common in acute renal failure
ii) Acute renal failure: Causes a metabolic alkalosis (FALSE)
Causes a metabolic acidosis
iii) Acute renal failure: Total body potassium can be reduced by administration of an insulin dextrose infusion (FALSE)
Hyperkalaemia is common in ARF and can be rapidly fatal. The rate in change of serum potassium concentration is often more important than the absolute concentration. Guidelines suggest treating any hyperkalaemia above 6.5.
An insulin dextrose infusion helps to reduce serum potassium by encouraging cellular uptake of potassium, however it is only a temporary measure and does not change the total concentration of potassium in the body
iv) Acute renal failure: Intravenous calcium chloride is indicated in the treatment of hyperkalaemia (TRUE)
10ml of 10% calcium chloride IV stabalises the myocardium, reducing the risk of arrhythmia. (calcium is cardio-protective; hypocalcaemia and hyperkalaemia are a dangerous mix)
v) Acute renal failure: Calcium resonium can be used to lower total body potassium but works slowly (TRUE)
Calcium resonium can be given orally or rectally, it helps bind potassium and thus reduced total body potassium. It works slowly and is poorly tolerated via the oral route (it is like drinking a mixture of chalk and water!)
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27. Atrial septal defects
i) Predispose to the development of atrial fibrillation TRUE
ii) Predispose to recurrent chest infections in children TRUE
iii) Are associated with fixed splitting of the second heart sound on auscultation TRUE
iv) Typicaly cause clubbing FALSE
v) A chest radiograph will typicaly show reduced pulmonary vascular markings FALSE
Explanations
i) Atrial septal defects Predispose to the development of atrial fibrillation (TRUE)
Adults with untreated atrial septal defects commonly develop atrial fibrillation in their 30s and 40s.
ii) Atrial septal defects Predispose to recurrent chest infections in children (TRUE)
Chest infections occur more commonly in children with atrial septal defects
iii) Atrial septal defects Are associated with fixed splitting of the second heart sound on auscultation (TRUE)
Fixed splitting implies splitting of the heart sound that does not vary with respiration. This occurs due to a left to right shunt causing increased right ventricular volumes, resulting in delayed right ventricular systole.
iv) Atrial septal defects Typicaly cause clubbing (FALSE)
Clubbing is associated with cyanotic heart disease. Atrial septal defects typically cause a left to right shunt and therefore oxygen depleted blood does not tend to cross on to the left side of the heart and thus arterial oxygen tension is usually normal.
v) Atrial septal defects A chest radiograph will typicaly show reduced pulmonary vascular markings (FALSE)
The left to right shunt will result in increased volume on the right side and therefore increased pulmonary blood flow resulting in enlarged pulmonary arteries and increased vascular markings.
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28 .The following statements about inflammatory bowel disease are true
i) Crohn’s disease only affects the small bowel FALSE
ii) Non-caseating granulomas are a feature of Crohn’s disease TRUE
iii) Ulcerative colitis often extends beyond the mucosa and sub-mucosa FALSE
iv) Crypt abscesses are a recognised feature of ulcerative colitis TRUE
v) A barium enema is indicated following the plain abdominal appearance of toxic megacolon FALSE
Explanations
i) The following statements about inflammatory bowel disease are true Crohn’s disease only affects the small bowel (FALSE)
Chron's disease can affect any part of the GI tract: anywhere from the mouth to the anus. The terminal ileum is a common site
ii) The following statements about inflammatory bowel disease are true Non-caseating granulomas are a feature of Crohn’s disease (TRUE)
Non-caseating granulomas are a key features of Crohn's disease
iii) The following statements about inflammatory bowel disease are true Ulcerative colitis often extends beyond the mucosa and sub-mucosa (FALSE)
Ulcerative colitis is characteristically limited to the mucosa and sub-mucosa although performation of the bowel may occur. This contrasts with Crohn's, where lesions are transmural
iv) The following statements about inflammatory bowel disease are true Crypt abscesses are a recognised feature of ulcerative colitis (TRUE)
Ulcerative colitis is characterized by accumulations of polymorphonuclear neutrophils in the crypts of the colon: crypt abscesses
Some are also seen in Crohn's, but to a lesser extent
v) The following statements about inflammatory bowel disease are true A barium enema is indicated following the plain abdominal appearance of toxic megacolon (FALSE)
There is a significant danger of bowel perforation if an enema is performed!
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29 . The following are predisposing factors for gallstones.
i) Obesity. TRUE
ii) Nulliparity FALSE
iii) Oral Contraceptive Pill. TRUE
iv) Chronic Haemolytic Disease TRUE
v) Male. FALSE
Explanations
i) The following are predisposing factors for gallstones. Obesity. (TRUE)
Obesity increases risk.
ii) The following are predisposing factors for gallstones. Nulliparity (FALSE)
Multiparity increases the risk of gallstones.
iii) The following are predisposing factors for gallstones. Oral Contraceptive Pill. (TRUE)
Certain drugs can be predisposing factors for example oral contraceptives and diuretics.
iv) The following are predisposing factors for gallstones. Chronic Haemolytic Disease (TRUE)
Due to excess production of bile pigments.
v) The following are predisposing factors for gallstones. Male. (FALSE)
More common in females.
Further notes:
Remember all the 'Fs' for predisposing factors of gallstones: Fat, Female, Forty, Fertile (ie multiparity).
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30 . Renal cancers:
i) Are more common in coffee drinkers TRUE
ii) Spread is both haematogenous and lympatic TRUE
iii) Bone secondarys are characteristically osteosclerotic FALSE
iv) Is associated with characteristic 'cannon ball' metastases in the lungs TRUE
v) Respond well to chemotherapy FALSE
Explanations
i) Renal cancers: Are more common in coffee drinkers (TRUE)
RCC is more common in males, cigarette smokers and coffee drinkers.
ii) Renal cancers: Spread is both haematogenous and lympatic (TRUE)
Spread is haematogenous and lymphatic. Common sites of metastases include the lung, liver and bones.
iii) Renal cancers: Bone secondarys are characteristically osteosclerotic (FALSE)
Bone secondaries are usually purely lytic
iv) Renal cancers: Is associated with characteristic 'cannon ball' metastases in the lungs (TRUE)
Is associated with characteristic 'cannon ball' metastases in the lungs
v) Renal cancers: Respond well to chemotherapy (FALSE)
Surgical resection is the only hope of cure. Renal cancer responds poorly to chemotherapy and radiotherapy.
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31.Tumours of the salivary glands:
i) Over 50% of salivary tumours arise in the sub-mandibular gland FALSE
ii) Over 75% of all salivary tumours are malignant FALSE
iii) FNA is a useful diagnostic tool TRUE
iv) Warthin's tumour is characteristically aggressive and metastasises early FALSE
v) Frey's syndrome occurs immediaetly after parotid surgery in about 25% of cases FALSE
Explanations
i) Tumours of the salivary glands: Over 50% of salivary tumours arise in the sub-mandibular gland (FALSE)
80% of all salivary tumours arise in the parotid gland
ii) Tumours of the salivary glands: Over 75% of all salivary tumours are malignant (FALSE)
About 15% of all salivary tumours are malignant. The majority of salivary neoplasms are benign pleomorphic adenomas.
iii) Tumours of the salivary glands: FNA is a useful diagnostic tool (TRUE)
Diagnosis is made by FNA and CT
iv) Tumours of the salivary glands: Warthin's tumour is characteristically aggressive and metastasises early (FALSE)
Warthin's tumour (adenolymphoma) is benign. MAlignant transformation has not been observed. 5% recurrence rate after surgery. 10% are bilateral
v) Tumours of the salivary glands: Frey's syndrome occurs immediaetly after parotid surgery in about 25% of cases (FALSE)
Frey's syndrome is characterised by gustatory sweating and occurs after parotid surgery. It occurs in up to 25% of patients, BUT it is a late complication occuring at 6-9 months post surgery - it occurs because of in-appropriate re-growth of secretor motor nerve fibres that end up innervating the skin and sweat glands rather than the parotid gland itself.
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32. Hepatocellular carcinoma
i) Has an equal sex incidence FALSE
ii) Chromium exposure is a recognised risk factor FALSE
iii) Characteristically presents in the 4th or 5th decade of life in Western Countries FALSE
iv) Jaundice usually occurs early in the disease process FALSE
v) CA 125 is the most useful tumour marker and is used to screen for recurrent disase FALSE
Explanations
i) Hepatocellular carcinoma Has an equal sex incidence (FALSE)
Hepatocellular carcinoma is 4 times more common in men
ii) Hepatocellular carcinoma Chromium exposure is a recognised risk factor (FALSE)
Risk factots
- Chronic liver diseases, esp. hepatitis, alcohol related
- Aflatoxin
- Anabolic steroids
- Vinyl chloride (gaseous monomer used to create PVC)
iii) Hepatocellular carcinoma Characteristically presents in the 4th or 5th decade of life in Western Countries (FALSE)
Median age of presentation of 40 in Asia and Sub-Saharan Africa.
Median age of presentation is approximately 80 in America and Western Europe
iv) Hepatocellular carcinoma Jaundice usually occurs early in the disease process (FALSE)
Jaundice tends to occur late.
v) Hepatocellular carcinoma CA 125 is the most useful tumour marker and is used to screen for recurrent disase (FALSE)
Alpha fetoprotein (AFP) is the most useful marker and may be used to screen at risk populations as well as monitor for recurrent disease.
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33.
Bladder cancer
i) 25% of cases in the UK are squamous cell carcinomas FALSE
ii) T1 disease is best treated by radical cystectomy FALSE
iii) Intravesical installation of BCG may help decrease recurrence and progression of superficial bladder cancers TRUE
iv) Carcinoma in situ (Tis) is associated with a worse prognosis TRUE
v) T1 disease is associated with over 80% 5 year survival TRUE
Explanations
i) Bladder cancer 25% of cases in the UK are squamous cell carcinomas (FALSE)
95% of tumours in the UK are transitional cell carcinomas.
Squamous cell carcinomas account for less than 5% of cases in the UK, but are much more common in parts of the world where schistosomiasis is endemic
ii) Bladder cancer T1 disease is best treated by radical cystectomy (FALSE)
T1 disease is best treated by cystoscopic resection followed by continuous monitoring for recurrence /metanchronous tumour
iii) Bladder cancer Intravesical installation of BCG may help decrease recurrence and progression of superficial bladder cancers (TRUE)
BCG is a live attenuated organism that promotes an immunolgical reaction in the bladder that promotes destruction of the tumour. Should be avoided if there is gross haematuria as there is a low risk of systemic infection with BCG.
iv) Bladder cancer Carcinoma in situ (Tis) is associated with a worse prognosis (TRUE)
The presence of carcinoma in situ is a marker of poorer prognosis
v) Bladder cancer T1 disease is associated with over 80% 5 year survival (TRUE)
5 year survival statistics are good with 85-95% of those with T1 disease surviving for 5 years.
Superficial disease will commonly reccur but can be treated by reccurrent cystoscopic resection +/- immunological /chemotheraputic intravesical agents.
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34. Breast cancer:
i) 5-10% of cases have a familial predisposition TRUE
ii) Life time risk of breast cancer in the UK is just over 10% TRUE
iii) Nulliparity reduced the risk of breast cancer FALSE
iv) BRCA 1 gene is located on Chromosome 5 FALSE
v) Having a sister affected by breast cancer confers a greater risk than having your mother affected by breast cancer TRUE
Explanations
i) Breast cancer: 5-10% of cases have a familial predisposition (TRUE)
5-10% of cases have a familial predisposition, however only 2% are associated with BRCA 1 and BRCA 2
ii) Breast cancer: Life time risk of breast cancer in the UK is just over 10% (TRUE)
Epidemiological data suggests lifetime risks are:
USA: 1:7
UK: 1:9
iii) Breast cancer: Nulliparity reduced the risk of breast cancer (FALSE)
Breast cancer is strongly related to life time oestrogen exposure thus risk factors include:
- Early menarchy
- Late menopause
- Nulliparity (multiparity and earlier age of 1st pregnancy are relatively protective)
- HRT and OCP
iv) Breast cancer: BRCA 1 gene is located on Chromosome 5 (FALSE)
BRCA 1 gene Ch 17
BRCA 2 gene Ch 13
v) Breast cancer: Having a sister affected by breast cancer confers a greater risk than having your mother affected by breast cancer (TRUE)
Possible relative risks associated with the presence of disease in relatives:
- Mother x 1.8
- Sister x 2.5
- Mother and Sister x 5.6
- Mother and sister developing Ca at under 40 years: x 9.0
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35. Statistical analysis and audit:
i) A type I error is said to have occurred when the populations are different but the results are not statistically significant FALSE
ii) An unpaired T-test compares two populations based on the assumption that the two populations exhibit Gaussian distribution TRUE
iii) Parametric tests are performed when population groups follow a Gaussian distribution TRUE
iv) Audit seeks to define best practice by comparing treatment regimens FALSE
v) For a disease with an prevalence of 1/1000 a test is developed that is 100% sensitive and 90% specific. The positive predictive value of this test would be 10% FALSE
Explanations
i) Statistical analysis and audit: A type I error is said to have occurred when the populations are different but the results are not statistically significant (FALSE)
Type I error:
- 2 identical populations
- Statistics show a difference between populations when there is none
Type II error:
- 2 different populations
- Results fail to show a statistical difference
ii) Statistical analysis and audit: An unpaired T-test compares two populations based on the assumption that the two populations exhibit Gaussian distribution (TRUE)
An unpaired T-test compares two populations based on the assumption that the two populations exhibit Gaussian distribution
iii) Statistical analysis and audit: Parametric tests are performed when population groups follow a Gaussian distribution (TRUE)
Parametric tests are performed when population groups follow a Gaussian distribution
iv) Statistical analysis and audit: Audit seeks to define best practice by comparing treatment regimens (FALSE)
Audit involves identifying best practice (eg: by searching the literature). Current practice and outcomes are then studied and compared to best practice, if there are short commings current practice should be changed and then re-audit should be completed.
Research seeks to define best practice by comparing treatment regimens
v) Statistical analysis and audit: For a disease with an prevalence of 1/1000 a test is developed that is 100% sensitive and 90% specific. The positive predictive value of this test would be 10% (FALSE)
This question requires some thought and production of the table below:
| Diseased | Not diseased | ||
| Positive test result | 1 (true positive) | 100 (false positive) | Positive predictive value = [True positive /(true positive + false positive)] x100 = [1/(1+100)] x100 = 0.99% |
| Negative test result | 0 (false negative) | 899 (true negative) | Negative predictive value = [True negative / (true negative + false negative)] x100 = [899/(899 + 0)] x100 = 100% |
| Sensitivity = [True positive /(true positive + false negative)] x100 = [1/(1+0)] x 100 = 100% | Specificity = [True negative / (true negative + false positive)] x100 = [899/(899+100)] x100 = 89.9% |
We know that the prevalence is 1/1000, therefore we need 1000 in all (all squares add up to 1000) and only 1 person in the disease positive column. We also know the test is 100% sensitive - thus the one person must be in the true positive box. We also know that the disease negative column must add up to 999. We know the test is only 90% specific thus 10% of these 999 people will be in the false positive box and 90% will in in the true negative box. We can therefore complete the above table and can now calculate the negative and positice predictive values as above.
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