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  • Question 1 - A 68-year-old man underwent sigmoid resection with diverting colostomy for a ruptured sigmoid...

    Correct

    • A 68-year-old man underwent sigmoid resection with diverting colostomy for a ruptured sigmoid diverticulum 10 days ago. He received gentamicin and ampicillin post-op. 2 days after he was discharged from the hospital, he was readmitted because of high grade fever and chills. His blood culture grew Gram-negative bacilli. Which organism is most likely responsible for the patient's infection?

      Your Answer: Bacteroides fragilis

      Explanation:

      Bacteroides fragilis is an anaerobic, Gram-negative, rod-shaped bacterium. It is part of the normal flora of the human colon and is generally a commensal, but can cause infection if displaced into the bloodstream or surrounding tissue following surgery, disease, or trauma.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      11.6
      Seconds
  • Question 2 - A CT-scan report of a patient with gastric carcinoma shows that the lymph...

    Correct

    • A CT-scan report of a patient with gastric carcinoma shows that the lymph nodes around the coeliac trunk are enlarged. The coeliac trunk:

      Your Answer: Gives rise to the splenic, left gastric and common hepatic arteries

      Explanation:

      The coeliac trunk is a branch of the aorta arising just below the aortic hiatus of the diaphragm to pass nearly horizontally forward to divide into 3 large branches i.e. the left gastric, the hepatic and the splenic arteries. Occasionally it may give off one of the inferior phrenic arteries. It is covered by the lesser omentum and on the right side bordered by the right coeliac ganglion and the cardiac end of the stomach. Inferiorly it is bordered by the upper border of the pancreas and splenic vein. The embryonic midgut is supplied by the superior mesenteric artery.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      17.6
      Seconds
  • Question 3 - Which of the following is the most likely cause of massive splenomegaly in...

    Correct

    • Which of the following is the most likely cause of massive splenomegaly in a 35-year old gentleman?

      Your Answer: Myelofibrosis

      Explanation:

      Causes of massive splenomegaly include chronic myelogenous leukaemia, chronic lymphocytic leukaemia, lymphoma, hairy cell leukaemia, myelofibrosis, polycythaemia vera, sarcoidosis, Gaucher’s disease and malaria.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      4.5
      Seconds
  • Question 4 - A 78-year-old diabetic man undergoes renal function tests. Which of the following substances...

    Correct

    • A 78-year-old diabetic man undergoes renal function tests. Which of the following substances will be the most accurate for measuring glomerular filtration rate (GFR)?

      Your Answer: Inulin

      Explanation:

      Glomerular filtration rate (GFR) is the volume of fluid filtered from the renal glomerular capillaries into the Bowman’s capsule per unit time. Clinically, this is often measured to determine renal function. Inulin was originally used as it is not reabsorbed by the kidney after glomerular filtration, therefore its rate of excretion is directly proportional to the rate of filtration of water and solutes across the glomerular filter. However, in clinical practice, creatinine clearance is used to measure GFR. Creatinine is an endogenous molecule, synthesised in the body, that is freely filtered by the glomerulus (but also secreted by the renal tubules in very small amounts). Creatinine clearance exceeds GFR due to creatinine secretion, and is therefore a close approximation of the GFR.

    • This question is part of the following fields:

      • Physiology
      • Renal
      8
      Seconds
  • Question 5 - The circle of Willis is an arterial anastomosis in the base of the...

    Correct

    • The circle of Willis is an arterial anastomosis in the base of the brain and is one of the cerebrovascular safeguards in the brain. Where is the circle of Willis contained?

      Your Answer: Cisterna basalis

      Explanation:

      Cisterns refers to a system of intercommunicating pools formed by the subarachnoid space at the base of the brain and around the brainstem. Cisterna basalis/basal cistern (interpeduncular cistern) is found at the base of the brain between the two temporal lobes and it contains the arterial circle of Willis. The lumbar cistern is contained in the spinal canal while the foramen magna refers to the opening at the base of the skull though which the spinal cord enters into the skull.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      2.9
      Seconds
  • Question 6 - Reed-Sternberg cells are characteristic of: ...

    Correct

    • Reed-Sternberg cells are characteristic of:

      Your Answer: Hodgkin's lymphoma

      Explanation:

      Reed-Sternberg cells are characteristic of Hodgkin’s lymphoma.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      8
      Seconds
  • Question 7 - An electronic manufacturing engineer had abdominal distension and underwent a CT scan of...

    Correct

    • An electronic manufacturing engineer had abdominal distension and underwent a CT scan of the abdomen. Thereafter he was diagnosed with hepatic angiosarcoma. Exposure to what agent is responsible for the development of this neoplasm?

      Your Answer: Arsenic

      Explanation:

      Hepatic angiosarcomas are associated with particular carcinogens which includes: arsenic , thorotrast, and polyvinyl chloride. With exposure to this three agents, there is a very long latent period of many years between exposure and the development of tumours.

    • This question is part of the following fields:

      • Neoplasia
      • Pathology
      7.1
      Seconds
  • Question 8 - The most likely cause of prominent U waves on the electrocardiogram (ECG) of...

    Correct

    • The most likely cause of prominent U waves on the electrocardiogram (ECG) of a patient is:

      Your Answer: Hypokalaemia

      Explanation:

      The U-wave, not always visible in ECGs, is thought to represent repolarisation of papillary muscles or Purkinje fibres. When seen, it is very small and occurs after the T-wave. Inverted U-waves indicate myocardial ischaemia or left ventricular volume overload. Prominent U-waves are most commonly seen in hypokalaemia. Other causes include hypercalcaemia, thyrotoxicosis, digitalis exposure, adrenaline and class 1A and 3 anti-arrhythmic agents. It can also be seen in congenital long-QT syndrome and in intracranial haemorrhage.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      3.9
      Seconds
  • Question 9 - A 30-year-old female was alarmed when she started to experience hair loss and...

    Correct

    • A 30-year-old female was alarmed when she started to experience hair loss and balding, however, she also noted increased hair on her face and body and developed an acne breakout. Deepening of her voice also became prominent. She was referred to an oncologist and was diagnosed with a hormone-producing tumour. What is the most likely diagnosis ?

      Your Answer: Arrhenoblastoma

      Explanation:

      Arrhenoblastoma, known as ‘Sertoli–Leydig tumour’ is a rare ovarian stromal neoplasm that secretes testosterone. It is mostly seen in women in the reproductive years. The key clinical features of this tumour is due to excessive production of testosterone which leads to progressive masculinisation in a woman who was typical normal beforehand. The lesion tends to grow slowly and rarely metastasises. Treatment is surgical removal of the tumour and the prognosis is generally good.

    • This question is part of the following fields:

      • Neoplasia
      • Pathology
      19.1
      Seconds
  • Question 10 - Which of the following statements regarding the arteries in the neck are TRUE?...

    Correct

    • Which of the following statements regarding the arteries in the neck are TRUE?

      Your Answer: The thyrocervical trunk typically gives rise to the inferior thyroid artery, transverse cervical artery and suprascapular artery

      Explanation:

      The thyrocervical trunk is one of the three branches of the first part of the subclavian artery and gives numerous branches which supply viscera of the neck, the brachial plexus, neck muscles and scapular anastomoses. The vertebral arteries are major arteries of the neck. They arise as branches from the subclavian arteries and merge to form the single midline basilar artery. The carotid sinus is a dilated area at the base of the internal carotid artery just superior to the bifurcation of the internal carotid and external carotid at the level of the superior border of thyroid cartilage.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      13.4
      Seconds
  • Question 11 - Dicloxacillin is an antibiotic; the subclass that dicloxacillin belongs to is: ...

    Correct

    • Dicloxacillin is an antibiotic; the subclass that dicloxacillin belongs to is:

      Your Answer: Penicillin

      Explanation:

      Dicloxacillin is a narrow-spectrum beta-lactam antibiotic. It is used to treat infections caused by susceptible Gram-positive bacteria and most effective against beta-lactamase-producing organisms such as Staphylococcus aureus. To decrease the development of resistance, dicloxacillin is recommended to treat infections that are suspected or proven to be caused by beta-lactamase-producing bacteria.

    • This question is part of the following fields:

      • Pathology
      • Pharmacology
      6.3
      Seconds
  • Question 12 - Which of the following is a large artery that runs immediately posterior to...

    Correct

    • Which of the following is a large artery that runs immediately posterior to the stomach?

      Your Answer: Splenic

      Explanation:

      The splenic artery is the large artery that would be found running off the posterior wall of the stomach. It is a branch of the coeliac trunk and sends off branches to the pancreas before reaching the spleen. The gastroduodenal artery on the other hand is found inferior to the stomach, posterior to the first portion of the duodenum. The left gastroepiploic artery runs from the left to the right of the greater curvature of the stomach. The common hepatic artery runs on the superior aspect of the lesser curvature of the stomach, and is a branch of the coeliac trunk. The superior mesenteric artery arises from the abdominal aorta just below the junction of the coeliac trunk.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      21.5
      Seconds
  • Question 13 - Calculate the stroke volume in an adult male with the following parameters:

    Heart...

    Correct

    • Calculate the stroke volume in an adult male with the following parameters:

      Heart rate 70 beats/min

      Arterial [O2] 0.24 ml O2/min

      Venous [O2] 0.16 ml O2/mi

      Whole body O2 consumption 500 ml/min

      Pulmonary diastolic pressure 15 mmHg

      Pulmonary systolic pressure 25 mmHg

      Wedge pressure 5 mmHg.

      Your Answer: 90 ml

      Explanation:

      Fick’s principle states that, VO2 = (CO × CAO2) – (CO × CVO2) where VO2 = oxygen consumption, CO = cardiac output, CAO2 = oxygen concentration of arterial blood and CVO2 = oxygen concentration of venous blood. Thus, CO = VO2/CAO2– CVO2, CO = 500/0.24–0.16, CO = 500/0.8, CO = 6.25 l/min. Cardiac output is also given by product of stroke volume and heart rate. Thus, stroke volume = cardiac output / heart rate = 6.25/70 × 1000 stroke volume = 90 ml approximately.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      34.9
      Seconds
  • Question 14 - A 10-year-old boy was sent for an x-ray of the leg because he...

    Incorrect

    • A 10-year-old boy was sent for an x-ray of the leg because he was complaining of pain and swelling. The x-ray showed the classic sign of Codman's triangle. What is the most likely diagnosis of this patient?

      Your Answer: Chondrosarcoma

      Correct Answer: Osteosarcoma

      Explanation:

      Codman’s triangle is the triangular area of new subperiosteal bone that is created when a lesion, often a tumour, raises the periosteum away from the bone. The main causes for this sign are osteosarcoma, Ewing’s sarcoma, eumycetoma, and a subperiosteal abscess.

    • This question is part of the following fields:

      • Neoplasia
      • Pathology
      18.4
      Seconds
  • Question 15 - A 34-year old gentleman presented with acute pancreatitis to the emergency department. On...

    Correct

    • A 34-year old gentleman presented with acute pancreatitis to the emergency department. On enquiry, there was found to be a history of recurrent pancreatitis, eruptive xanthomas and raised plasma triglyceride levels associated with chylomicrons. Which of the following will be found deficient in this patient?

      Your Answer: Lipoprotein lipase

      Explanation:

      The clinical features mentioned here suggest the diagnosis of hypertriglyceridemia due to lipoprotein lipase (LPL) deficiency. LPL aids in hydrolysing the lipids in lipoproteins into free fatty acids and glycerol. Apo-CII acts as a co-factor. Deficiency of this enzyme leads to hypertriglyceridemia.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      53.2
      Seconds
  • Question 16 - Anthrax is an infection caused by the bacterium Bacillus anthracis. Anthrax spores have been used...

    Correct

    • Anthrax is an infection caused by the bacterium Bacillus anthracis. Anthrax spores have been used as a biological warfare weapon. What is the drug of choice in treating anthrax infection?

      Your Answer: Ciprofloxacin

      Explanation:

      Early antibiotic treatment of anthrax is essential. A delay may significantly lessen the chances for survival of the patient. Treatment for anthrax infection include large doses of intravenous and oral antibiotics, such as fluoroquinolones (ciprofloxacin), doxycycline, erythromycin, vancomycin, or penicillin.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      12.8
      Seconds
  • Question 17 - Which nuclei of the posterior grey column of the spinal cord are likely...

    Correct

    • Which nuclei of the posterior grey column of the spinal cord are likely affected in a patient who has lost the sensation of pain and temperature?

      Your Answer: Substantia gelatinosa

      Explanation:

      Substantia gelatinosa is one of the nuclei in the posterior grey column along side other posterior grey column nuclei like the nucleus dorsalis, nucleus proprius, and posteromarginal nucleus. These nuclei are a collection of cells in the posterior grey area found in throughout the spinal cord. The substantia gelatinosa receives direct input from the dorsal nerve roots (sensory), especially from thermoreceptors and nociceptors (receptors for temperature and pain).

    • This question is part of the following fields:

      • Anatomy
      • Neurology
      13.3
      Seconds
  • Question 18 - During gastrectomy, the operating surgeon ligates the short gastric arteries along the greater...

    Correct

    • During gastrectomy, the operating surgeon ligates the short gastric arteries along the greater curvature of the stomach. Where do the short gastric arteries branch from?

      Your Answer: Splenic artery

      Explanation:

      Short gastric arteries arise from the splenic artery at the end or from its terminal divisions. They are about 5 or 7 in number, passing from the left to the right in between the layers of the gastrosplenic ligament to be distributed along the greater curvature of the stomach.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      11.1
      Seconds
  • Question 19 - An operation to remove a segment of the oesophagus through a right thoracotomy...

    Correct

    • An operation to remove a segment of the oesophagus through a right thoracotomy is complicated when a tear develops in a large venous structure in the posterior mediastinum that empties into the superior vena cava. Which of the following structures is likely to be injured?

      Your Answer: Azygos vein

      Explanation:

      The azygos vein is formed by the union of the right subcostal veins and the ascending lumbar veins at the level of the 12th thoracic vertebra. It enters the thorax through the aortic hiatus to ascend in the posterior mediastinum and arching over the right main bronchus posteriorly at the root of the right lung to join the superior vena cava before it pierces the pericardium.

      The basilic vein is a vein on the medial aspect of the arm that ascends to become the axillary vein.

      The cephalic vein is also a vein of the arm.

      The external jugular and brachiocephalic vein are not in the posterior mediastinum.

      The median cubital vein is found in the cubital fossa of the arm.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      11.4
      Seconds
  • Question 20 - Which of the following muscle divide the posterior triangle of the neck into...

    Correct

    • Which of the following muscle divide the posterior triangle of the neck into the occipital and the subclavian triangle?

      Your Answer: Inferior belly of the omohyoid

      Explanation:

      The posterior triangle (or lateral cervical region) is a region of the neck bounded in front by the sternocleidomastoid; behind, by the anterior margin of the trapezius; inferiorly by the middle third of the clavicle and superiorly by the occipital bone. The posterior triangle is crossed, about 2.5 cm above the clavicle, by the inferior belly of the omohyoid muscle, which divides the space into two triangles: an upper or occipital triangle and a lower or subclavian triangle (or supraclavicular triangle).

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      16.8
      Seconds
  • Question 21 - An explorative laparotomy is done on a 23 year old following a gunshot...

    Correct

    • An explorative laparotomy is done on a 23 year old following a gunshot abdominal injury through the right iliac fossa. It is found that the ileocolic artery is severed and the bullet had perforated the caecum. From which branch does the ileocolic artery originate?

      Your Answer: Superior mesenteric artery

      Explanation:

      Ileocolic artery branches off from the superior mesenteric artery. It then divides to give a superior and inferior branch.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      13.9
      Seconds
  • Question 22 - The Brunner glands secrete an alkaline product that helps maintain an optimal pH...

    Correct

    • The Brunner glands secrete an alkaline product that helps maintain an optimal pH for pancreatic enzyme activity. Where are these glands located?

      Your Answer: Submucosa of the duodeneum

      Explanation:

      The Brunner glands are located in the submucosa of the duodenum. These glands are connected to the interstitial lumen by ducts that open into certain crypts. They secrete an alkaline product that protects the duodenal mucosa from the acidic chyme and helps achieve an optimal pH for the enzymes.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      10.6
      Seconds
  • Question 23 - A patient is brought to the accident and emergency department. He is said...

    Correct

    • A patient is brought to the accident and emergency department. He is said to have been involved in a mall explosion. Chest imaging reveals metal fragments in his thoracic cavity. He also has a pericardial effusion suggestive of a pericardial tear. An emergency thoracotomy is done which revealed a tear of the pericardium inferiorly. The surgeon began to explore for fragments in the pericardial sac with his hand from below the apex. He slips his fingers upward and to the right within the sac until they were stopped by the cul-de-sac formed by the pericardial reflection near the base of the heart. His finger tips were now in the:

      Your Answer: Oblique pericardial sinus

      Explanation:

      Transverse sinus: part of pericardial cavity that is behind the aorta and pulmonary trunk and in front of the superior vena cava separating the outflow vessels from the inflow vessels.

      Oblique pericardial sinus: is behind the left atrium where the visceral pericardium reflects onto the pulmonary veins and the inferior vena cava. Sliding a finger under the heart will take you to this sinus.

      Coronary sinus: large vein that drains the heart into the right atrium. Located on the surface of the heart.

      Coronary sulcus: groove on the heart demarcating the atria from the ventricles.

      Costomediastinal recess: part of the pleural sac where the costal pleura transitions to become the mediastinal pleura.

      Sulcus terminalis: a groove between the right atrium and the vena cava.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      10.6
      Seconds
  • Question 24 - Which one of the following muscles is innervated by the facial nerve? ...

    Correct

    • Which one of the following muscles is innervated by the facial nerve?

      Your Answer: Buccinator

      Explanation:

      Buccinator is a muscle of facial expression and is therefore innervated by the facial nerve. The lateral pterygoid, masseter, anterior belly of digastric and temporalis are all muscles of mastication and therefore innervated by the mandibular division of the trigeminal nerve.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck; Neurology
      5.5
      Seconds
  • Question 25 - A 65-year old patient with altered bowl movement experienced the worsening of...

    Correct

    • A 65-year old patient with altered bowl movement experienced the worsening of shortness of breath and exertional chest pains over the course of 8 weeks. Examination shows pallor and jugular venous distension. Furthermore, a test of the stool for occult blood is positive. Laboratory studies show:

      Haemoglobin 7.4 g/dl

      Mean corpuscular volume 70 fl Leukocyte count 5400/mm3

      Platelet count 580 000/mm3 Erythrocyte sedimentation 33 mm/h

      A blood smear shows hypochromic, microcytic RBCs with moderate poikilocytosis. Which of the following is the most likely diagnosis?

      Your Answer: Iron deficiency anaemia

      Explanation:

      Iron deficiency anaemia is the most common type of anaemia. It can occur due to deficiency of iron due to decreased intake or due to faulty absorption. An MCV less than 80 will indicated iron deficiency anaemia. On the smear the RBC will be microcytic hypochromic and will also show piokilocytosis. iron profiles tests are important to make a diagnosis. Clinically the patient will be pale and lethargic.

    • This question is part of the following fields:

      • General
      • Physiology
      22.1
      Seconds
  • Question 26 - A 17-year-old female was given an antibiotic for a urinary tract infection. After...

    Correct

    • A 17-year-old female was given an antibiotic for a urinary tract infection. After taking the medication the patient developed Steven-Johnson syndrome. Which particular antibiotic usually causes Steven-Johnson syndrome?

      Your Answer: Sulphonamides

      Explanation:

      Stevens–Johnson syndrome (SJS) is a type of severe skin reaction. The most common cause is certain medications such as lamotrigine, carbamazepine, allopurinol, sulphonamide antibiotics, and nevirapine.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      4.2
      Seconds
  • Question 27 - How much blood can the pulmonary vessels of a 45-year-old healthy man accommodate...

    Incorrect

    • How much blood can the pulmonary vessels of a 45-year-old healthy man accommodate when he is at rest?

      Your Answer: 250 ml

      Correct Answer: 500 ml

      Explanation:

      Pulmonary circulation is the portion of the cardiovascular system which carries deoxygenated blood away from the heart, to the lungs, and returns oxygenated blood back to the heart. The vessels of the pulmonary circulation are very compliant (easily distensible) and so typically accommodate about 500 ml of blood in an adult man. This large lung blood volume can serve as a reservoir for the left ventricle, particularly during periods when left ventricular output momentarily exceeds venous return.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      12.3
      Seconds
  • Question 28 - The middle meningeal artery is the largest among the arteries that supplies that...

    Correct

    • The middle meningeal artery is the largest among the arteries that supplies that dura mater of the brain. The middle meningeal artery is a branch of the?

      Your Answer: Maxillary artery

      Explanation:

      The middle meningeal artery is the largest of the three (paired) arteries that supply the meninges.

      The middle meningeal artery is a large arterial branch of the maxillary artery which is a terminal branch of the external carotid artery. Upon originating, the middle meningeal artery passes through the foramen spinosum. In the skull, it courses in the middle cranial fossa where it provides several branches.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      5.6
      Seconds
  • Question 29 - In the human body, veins often run a course parallel to the artery...

    Correct

    • In the human body, veins often run a course parallel to the artery that has the same name. Which of the following listed veins doesn't run parallel to the artery of the same name?

      Your Answer: Inferior mesenteric

      Explanation:

      The inferior mesenteric artery and inferior mesenteric vein don’t run in tandem because the vein is part of the portal venous system-draining into the splenic vein which drains into the hepatic portal vein. The inferior mesenteric artery is a branch of the descending aorta at the level of L3. The inferior mesenteric vein and artery, however, drain the same region i.e. the descending and sigmoid colon and rectum.

      Superior epigastric vessels course together and are the continuation of the internal thoracic artery and vein.

      Superficial circumflex iliac vessels course together in the superficial fat of the abdominal wall.

      Superior rectal vessels are the terminal ends of the inferior mesenteric vessels, located on the posterior surface of the rectum.

      The ileocolic artery and vein are branches off the superior mesenteric vessels. Both course in the mesentery, supplying/draining the caecum, appendix, terminal portion of the ileum. The inferior epigastric vessels run together.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      7.8
      Seconds
  • Question 30 - A 25-year-old female had a painful abdomen and several episodes of vomiting. She...

    Correct

    • A 25-year-old female had a painful abdomen and several episodes of vomiting. She was severely dehydrated when she was brought to the hospital. Her ABG showed a pH 7.7, p(O2) 75 mmHg, p(CO2) 46 mmHg and bicarbonate 48 mmol/l. The most likely interpretation of this ABG report would be:

      Your Answer: Metabolic alkalosis

      Explanation:

      Metabolic alkalosis is a primary increase in bicarbonate (HCO3−) with or without compensatory increase in carbon dioxide partial pressure (Pco2); pH may be high or nearly normal. Metabolic alkalosis occurs as a consequence of a loss of H+ from the body or a gain in HCO3 -. In its pure form, it manifests as alkalemia (pH >7.40). As a compensatory mechanism, metabolic alkalosis leads to alveolar hypoventilation with a rise in arterial carbon dioxide tension p(CO2), which diminishes the change in pH that would otherwise occur. Normally, arterial p(CO2) increases by 0.5–0.7 mmHg for every 1 mmol/l increase in plasma bicarbonate concentration, a compensatory response that occurs very rapidly. If the change in p(CO2) is not within this range, then a mixed acid–base disturbance occurs. Likewise, if the increase in p(CO2) is less than the expected change, then a primary respiratory alkalosis is also present. However an elevated serum bicarbonate concentration can also occur due to a compensatory response to primary respiratory acidosis. A bicarbonate concentration greater than 35 mmol/l is almost always caused by metabolic alkalosis (as is the case in this clinical scenario). Calculation of the serum anion gap can also help to differentiate between primary metabolic alkalosis and the metabolic compensation for respiratory acidosis. The anion gap is frequently elevated to a modest degree in metabolic alkalosis because of the increase in the negative charge of albumin and the enhanced production of lactate. However, the only definitive way to diagnose metabolic alkalosis is by performing a simultaneous blood gases analysis, which reveals elevation of both pH and arterial p(CO2) and increased calculated bicarbonate.

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Pathology
      13.3
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Microbiology (3/3) 100%
Pathology (9/10) 90%
Abdomen (6/6) 100%
Anatomy (14/14) 100%
Haematology (2/2) 100%
Physiology (5/6) 83%
Renal (1/1) 100%
Head & Neck (4/4) 100%
Neoplasia (2/3) 67%
Cardiovascular (2/2) 100%
Pharmacology (1/1) 100%
Gastroenterology (1/1) 100%
Neurology (1/1) 100%
Thorax (2/2) 100%
Head & Neck; Neurology (1/1) 100%
General (1/1) 100%
Respiratory (0/1) 0%
Fluids & Electrolytes (1/1) 100%
Passmed