PHYSIO 3 Flashcards
A 34 year old man presents with a peptic ulcer. Which of the following is responsible for the release of gastric acid?
Chief cells Parietal cells Brunners Glands G Cells None of the above
Parietal cells
Parietal cells are responsible for the release of gastric acid. Brunners glands are found in the duodenum.
Which of the following does not lead to relaxation of the lower oesophageal sphincter?
Metoclopramide Botulinum toxin type A Nicotine Alcohol Theophylline
Metoclopramide
Metoclopramide acts directly on the smooth muscle of the LOS to cause it to contract.
Theophylline is a phosphodiesterase inhibitor (mimics action of prostaglandin E1) which causes relaxation of the LOS.
Which of the following is not released from the islets of Langerhans?
Pancreatic polypeptide Glucagon Secretin Somatostatin Insulin
Secretin
Secretin is released from mucosal cells in the duodenum and jejunum.
Which of the following is not classically seen in coning resulting from raised intra cranial pressure?
Coma Hypotension Unreactive mid sized pupils Cheyne Stokes style respiratory efforts Bradycardia
Hypotension
Cushings triad
Widening of the pulse pressure
Respiratory changes
Bradycardia
Due to raised ICP systemic hypertension is usually seen. Compression of the respiratory centre will typically result in Cheyne Stokes style respiration.
Control of ventilation. Which statement is false?
Peripheral chemoreceptors are located in the bifurcation of the carotid arteries and arch of the aorta Central chemoreceptors respond to changes in O2 The respiratory centres control the rate and depth of respiration Involuntary control of respiration is from the medulla and pons Irritant receptors cause bronchospasm
Central chemoreceptors respond to changes in O2
- Central chemoreceptors: Respond to increased H+ in BRAIN INTERSTITIAL FLUID to increase ventilation.
A 54 year old lady has her serum calcium measured. Assuming her renal function is normal, what proportion of calcium filtered at the glomerulus will be reabsorbed by the renal tubules?
5% 15% 25% 50% 95%
95%
Most filtered calcium is reabsorbed (95%) a rare disorder of familial hypocalcemic calciurea may affect this proportion.
Which of the following does not cause hyperkalaemia?
Haemolysis Burns Familial periodic paralysis Type 4 renal tubular acidosis Severe malnutrition
Severe malnutrition
‘Machine’ - Causes of Increased Serum K+
M - Medications - ACE inhibitors, NSAIDS A - Acidosis - Metabolic and respiratory C - Cellular destruction - Burns, traumatic injury H - Hypoaldosteronism, haemolysis I - Intake - Excessive N - Nephrons, renal failure E - Excretion - Impaired
Familial periodic paralysis has subtypes associated with hyper and hypokalaemia.
Which of the following statements is true of glucagon?
Glucagon is produced in response to hyperglycaemia Released by beta cells Inhibits gluconeogenesis Produced in response to an increase of amino acids Composed of 2 alpha polypeptide chains linked by hydrogen bonds
Produced in response to an increase of amino acids
Glucagon is a protein comprised of a single polypeptide chain.
Produced by alpha cells of pancreatic islets of Langerhans in response to hypoglycaemia and amino acids.
It increases plasma glucose and ketones
A 52 year old man develops septic shock following a Hartmans procedure for perforated diverticular disease. He is started on an adrenaline infusion. Which of the following is least likely to occur?
Peripheral vasoconstriction Coronary artery vasospasm Gluconeogenesis Lipolysis Tachycardia
Coronary artery vasospasm
It’s cardiac effects are mediated via β 1 receptors. The coronary arteries which have β 2 receptors are unaffected.
Intra cranial pressure is governed by the principles of the Monroe-Kellie doctrine. To which of the following does this concept not apply?
A 2 month old child A 2 year old child A 5 year old child A 10 year old child An adult
A 2 month old child
The Monroe-Kelly Doctrine assumes that the cranial cavity is a rigid box. In children with non fused fontanells this is not the case.
Which of the following is not caused by cortisol in the stress response?
Anti-inflammatory effects Hypoglycaemia Skeletal muscle protein breakdown Stimulation of lipolysis Mineralocorticoid effects
Hypoglycaemia
An ‘anti insulin’ effect occurs leading to hyperglycaemia.
Which of the following features does not put a patient at risk of refeeding syndrome?
BMI < 16 kg/m2 Alcohol abuse Thyrotoxicosis Chemotherapy Diuretics
Thyrotoxicosis
Diuretics increase the risk of re-feeding syndrome through a process of increasing the risk of depletion of key electrolytes.
Which of the following statements relating to the regulation of renal blood flow is untrue?
In a healthy 70Kg male, the glomerular filtration rate will be the same at a systolic blood pressure of 120mmHg as a systolic blood pressure of 95 mmHg Over 90% of the blood supply to the kidney is distributed to the cortex The kidney receives approximately 25% of the total cardiac output at rest A decrease in renal perfusion pressure will cause the juxtaglomerular cells to secrete renin Systolic blood pressures of less than 65mmHg will cause the mesangial cells to secrete aldosterone
Systolic blood pressures of less than 65mmHg will cause the mesangial cells to secrete aldosterone
Mesangial cells are contractile cells that are located in the tubule and have no direct endocrine function.
A 39 year old lady undergoes a laparoscopic cholecystectomy as a daycase. The operation is more difficult than anticipated and the surgeon places a drain to the liver bed. In recovery 1.5 litres of blood is seen to enter the drain. Which of the following substances is the first to be released in this situation?
Angiotensinogen Renin Angiotensin I Angiotensin II Aldosterone
Renin
The decrease in blood pressure will be sensed by the juxtaglomerular cells in the kidney. This will cause renin secretion.
Which of the following drugs causes hyperkalaemia?
Heparin Ciprofloxacin Salbutamol Levothyroxine Codeine phosphate
Heparin
Both unfractionated and low-molecular weight heparin can cause hyperkalaemia. This is thought to be caused by inhibition of aldosterone secretion. Salbutamol is a recognised treatment for hyperkalaemia.
A 25-year-old man who has been morbidly obese for the past five years is reviewed in the surgical bariatric clinic. In this patient, release of which of the following hormones would increase appetite?
Leptin Thyroxine Adiponectin Ghrelin Serotonin
Ghrelin
Obesity hormones
leptin decreases appetite
ghrelin increases appetite
Whilst thyroxine can increase appetite it does not fit with the clinical picture being described.
Which of the following is not linked to excess glucocorticoids?
Osteonecrosis Osteoporosis Hypokalaemia Hyponatraemia Growth retardation in children
Hyponatraemia
Steroids are associated with retention of sodium and water.
A 54-year-old woman is admitted to the Surgical Admissions Unit with abdominal pain. Blood tests taken on admission show the following:
Magnesium 0.40 mmol/l (normal value 0.7-1.0 mmol/l)
Which one of the following factors is most likely to be responsible for this result?
Excessive resuscitation with intravenous saline Digoxin therapy Diarrhoea Hypothermia Rhabdomyolysis
Diarrhoea
Cause of low magnesium Diuretics Total parenteral nutrition Diarrhoea Alcohol Hypokalaemia, hypocalcaemia
A 43 year old man has a nasogastric tube inserted. The nurse takes a small aspirate of the fluid from the stomach and tests the pH of the aspirate. What is the normal intragastric pH?
0.5 2 4 5 6
2
The intragastric pH is usually 2. Administration of proton pump inhibitors can result in almost complete abolition of acidity
A 33 year old female is admitted for varicose vein surgery. She is fit and well. After the procedure she is persistently bleeding. She is known to have menorrhagia. Investigations show a prolonged bleeding time and increased APTT. She has a normal PT and platelet count. What is the most likely cause?
Anti phospholipid syndrome Haemophilia Factor V Leiden deficiency von Willebrands disease Protein C and S deficiency
von Willebrands disease
Bleeding post operatively, epistaxis and menorrhagia may indicate a diagnosis of vWD. Haemoarthroses are rare. The bleeding time is usually normal in haemophilia (X-linked) and vitamin K deficiency.
