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Basic concepts of fluid and electrolyte therapy 2nd edition – Part 5


Authors:
Dileep N. Lobo, MB BS, MS, DM, FRCS, FACS, FRCPE
Professor of Gastrointestinal Surgery Nottingham Digestive Diseases Centre and National
Institute for Health Research (NIHR) Nottingham Biomedical Research Centre
Nottingham University Hospitals and University of Nottingham
Queen’s Medical Centre, Nottingham, UK

Andrew J. P. Lewington, BSc, MB BS, MA (Ed), MD, FRCP
Consultant Renal Physician/Honorary Clinical Associate Professor
Leeds Teaching Hospitals
Leeds, UK

Simon P. Allison, MD, FRCP
Formerly Consultant Physician/Professor in Clinical Nutrition
Nottingham University Hospitals
Queen’s Medical Centre, Nottingham, UK

BJS Academy is delighted to host the second edition of the textbook ‘basic concepts of fluid and electrolyte therapy’, by Lobo, Lewington and Allison.

The authors have kindly divided the book into four easily digestible sections, and then some multiple choice questions at the end. Now test yourself that you have learned all you need to manage fluid balance in the surgical patient.

Surgeons sometimes focus a little too much on the technical aspects of their work, but without a sound knowledge of fluid and electrolyte management, their efforts in the operating theatre may easily be undone.

All surgeons will benefit from reading this book and gaining an understanding of how best to optimise fluid management in their patients.

Jonothan Earnshaw

Director, BJS Academy


The authors have made every effort to ensure that drug dosages in this book are in accordance with current recommendations and practice at the time of publication.

However, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions.



PREFACE

The first edition of this book was published in 2013 with the aim of improving understanding and clinical practice in the field of fluid and electrolyte therapy. Studies at that time suggested that, even though fluid and electrolyte preparations are the most commonly prescribed medications in hospitals, management of fluid and electrolyte disorders was suboptimal, possibly due to inadequate teaching, causing avoidable morbidity and even mortality. It should not be forgotten that fluid therapy, like other forms of treatment, has the capacity to do harm as well as good unless administered with care and based on sound knowledge.

A second edition was felt appropriate in the light of further advances in knowledge and practice over the last 9 years. We have updated the book, adding new chapters, figures, tables and flow charts to help the reader. New chapters include Ageing and Fluid Balance, Chronic Kidney Disease, Fluid Overload and the De-escalation Phase, and Perioperative Fluid Therapy and Outcomes. We have also tried to maintain consistency with published national and international guidelines, where available. References have now been cited in the text. To limit the number of references, we have tried, as far as possible to cite important review articles from which original studies may be sourced. However, relevant original works have been referred to when appropriate. We have included multiple choice questions so that readers may test their knowledge after reading the book.

The subject of fluid balance in paediatrics is not addressed and this book should be regarded as relevant to adults only. It is still not our intention to write a comprehensive textbook dealing with complex problems, but to provide a basic hand-book for students, nurses, trainee doctors and other health care professionals to help them to understand and solve some of the most common practical problems they face in day to day hospital practice. We hope that it will also stimulate them to pursue the subject in greater detail with further reading and practical experience. In difficult cases, or where there is uncertainty, trainee health care professionals should never hesitate to ask for advice from senior and experienced colleagues.

Dileep N. Lobo

Andrew J. P. Lewington

Simon P. Allison



MULTIPLE CHOICE QUESTIONS

Please choose the single best answer:

1 The best measure of water balance is:

  • a. Changes in serum sodium concentration
  • b. Accurately maintained fluid balance charts
  • c. Urinary osmolality
  • d. Serial weighing
  • e. Serum creatinine concentration

2 During the flow phase of the metabolic response to injury:

  • a. There is a high urinary sodium concentration
  • b. Hypokalaemia is common
  • c. Dangerous hyperkalaemia is common
  • d. There is renal retention of sodium and water
  • e. Urea production rates are decreased

3 The extracellular fluid volume:

  • a. Is 30% of body weight
  • b. Increases during short-term fasting
  • c. Is 20% of body weight
  • d. Consists of the interstitial fluid only
  • e. Is supported osmotically mainly by albumin

4 In health, albumin leaks from the intravascular space:

  • a. At a rate of 5%/h
  • b. At a rate of 10%/h
  • c. At a rate of 15%/h
  • d. At a rate that decreases after surgery
  • e. At a rate that decreases in sepsis

5 Albumin which leaks from the intravascular to the interstitial space:

  • a. Returns to the circulation via the veins
  • b. Is catabolised to its constituent amino acids
  • c. Is bound to glucose
  • d. Causes inflammation
  • e. Is returned to the circulation via the lymphatics

6 In diabetic ketoacidosis:

  • a. Treatment should be delayed until investigations are completed
  • b. Crystalloids should be infused without delay
  • c. The blood sugar should be lowered with insulin as rapidly as possible
  • d. As the blood sugar falls, serum sodium concentration also falls
  • e. Hypokalaemia is common

7 A fall in serum sodium concentration most commonly denotes:

  • a. A negative sodium balance
  • b. A positive water balance
  • c. Acute kidney injury
  • d. Hypoaldosteronism
  • e. Congestive heart failure

8 A serum potassium concentration >6 mmol/L:

  • a. Requires no action other than further monitoring
  • b. Is common in the early postoperative period
  • c. Risks cardiac arrest
  • d. Is commonly associated with diuretic treatment
  • e. Is suggestive of the syndrome of inappropriate antidiuretic hormone secretion

9 The strong ion difference of 0.9% saline solution is:

  • a. 0 mmol/L
  • b. 154 mmol/L
  • c. 30 mmol/L
  • d. 308 mmol/L
  • e. -10 mmol/L

10 A common presenting feature of hyperglycaemic hyperosmolar nonketotic state is:

  • a. Acidosis
  • b. Acidaemia
  • c. Hypokalaemia
  • d. Negative salt balance
  • e. Positive water balance

11 The osmolality of 0.9% saline is:

  • a. 308 mOsm/kg
  • b. 308 mOsm/L
  • c. 154 mOsm/kg
  • d. 154 mOsm/L
  • e. 305 mOsm/kg

12 Hyperchloraemia is associated with:

  • a. A metabolic acidosis
  • b. A metabolic alkalosis
  • c. An increase in the strong ion difference
  • d. Hyponatraemia
  • e. Increased urine output

13 6% hydroxyethyl starch:

  • a. Is the fluid of choice for resuscitation of the septic patient
  • b. Increases the risk of acute kidney injury in critically ill patients
  • c. Has a greater risk of causing anaphylaxis than gelatins
  • d. Should be used in a minimum dose of 70 ml/kg/day
  • e. Should not be used for intraoperative goal directed fluid therapy

14 A feature of the refeeding syndrome is:

  • a. Hyperphosphataemia
  • b. Hypocalcaemia
  • c. Hypokalaemia
  • d. Hypernatraemia
  • e. Hyponatraemia

15 Infusion of hypotonic solutions can cause:

  • a. Cerebral oedema in neurosurgical patients
  • b. Hypernatraemia
  • c. Salt and water retention
  • d. Acute kidney injury
  • e. Oliguria

16 An intravenous fluid infusion rate of 41.6 ml/h delivers:

  • a. 1 litre over 36 hours
  • b. 1 litre over 24 hours
  • c. 1 litre over 6 hours
  • d. 2 litres over 24 hours
  • e. 1 litre over 18 hours

17 The preferred solution for maintenance of fluid balance intravenously is:

  • a. 0.9% saline
  • b. 4% dextrose in 0.18% saline with added potassium
  • c. Hartmann’s solution
  • d. 4% gelatin
  • e. 5% dextrose

18 The flow phase of the metabolic response to injury is characterised by:

  • a. Potassium retention
  • b. Water diuresis
  • c. Sodium retention
  • d. Hyponatraemia
  • e. Hyperkalaemia

19 A peripheral intravenous cannula should be resited at least:

  • a. Once a week
  • b. Daily
  • c. Every 72 hours
  • d. 12 hourly
  • e. Once a fortnight

20 Which one of the following statements about the properties of colloids is true?

  • a. The larger the size of molecules in the colloid solution the longer it is retained in the intravascular compartment
  • b. The oncotic pressure of the solution is inversely related to the number of molecules in the solution
  • c. The size of molecules in the colloid solution is inversely related to the half-life of the solution
  • d. The number of molecules in the colloid solution is inversely related to the half-life of the solution
  • e. The smaller the size of molecules in the colloid solution the longer it is retained in the intravascular compartment

21 Regarding body fluid compartments:

  • a. Body water comprises 85% of total body weight
  • b. The extra-cellular water compartment comprises 40% of total body weight
  • c. The intra-cellular water compartment comprises 20% of total body weight
  • d. The interstitial fluid compartment is part of the intra-cellular water compartment
  • e. The intavascular and interstitial fluid concentrations of electrolytes are similar

22 The following is the correct composition (in mmol/L) of Hartmann’s Solution:

  • a. Sodium 131, Potassium 5, Calcium 2, Chloride 111, Lactate 29
  • b. Sodium 154, Potassium 5, Calcium 2, Chloride 154, Lactate 20
  • c. Sodium 131, Potassium 3, Calcium 5, Chloride 50, Lactate 29
  • d. Sodium 154, Potassium 2, Calcium 2, Chloride 154, Lactate 20
  • e. Sodium 111, Potassium 5, Calcium 2, Chloride 111, Lactate 29

23 The following are required daily in healthy adults:

  • a. Water 35-55 ml/kg, Sodium 3-4 mmol/kg, Potassium 1-2 mmol/kg
  • b. Water 25-30 ml/kg, Sodium 1-1.2 mmol/kg, Potassium 1 mmol/kg
  • c. Water 10 ml/kg, Sodium 1 mmol/kg, Potassium 3 mmol/kg
  • d. Water 30 ml/kg, Sodium 3 mmol/kg, Potassium 1 mmol/kg
  • e. Water 35-55 ml/kg, Sodium 1-1.2 mmol/kg, Potassium 3 mmol/kg

24 Which one of the following statements about 0.9% sodium chloride solution (“Normal Saline”) is true?

  • a. 1-Litre contains 90 grams of sodium
  • b. It contains 131 mmol/L sodium
  • c. It contains 154 mmol/L chloride
  • d. It has a pH of 7.5
  • e. When given in excess it causes a hypocholoraemic alkalosis

25 The metabolic response to surgery or trauma causes:

  • a. Increased urinary loss of sodium, increased urinary loss of potassium, increased urine output
  • b. Decreased urinary loss of sodium, decreased urinary loss of potassium, increased urine output
  • c. Increased urinary loss of sodium, increased urinary loss of potassium, decreased urine output
  • d. Decreased urinary loss of sodium, decreased urinary loss of potassium, water retention, increased urine output
  • e. Decreased urinary loss of sodium, increased urinary loss of potassium, water retention, decreased urine output

26 The following are characteristics of 1-Litre of 5% Dextrose solution:

  • a. Sodium 154 mmol, Chloride 154 mmol, Glucose 500 grams, pH 4
  • b. Sodium 70 mmol, Chloride 70 mmol, Glucose 50 grams, pH 7.5
  • c. Sodium 0 mmol, Chloride 0 mmol, Glucose 500 grams, pH 7.5
  • d. Sodium 0 mmol, Chloride 0 mmol, Glucose 50 grams, pH 4
  • e. Sodium 70 mmol, Chloride 70 mmol, Glucose 50 grams, pH 6

27 The following are constituents of 1-Litre of Dextrose (4%)/Saline (0.18%) solution:

  • a. Sodium 154 mmol, Chloride 154 mmol, Glucose 40 grams
  • b. Sodium 31 mmol, Chloride 31 mmol, Glucose 40 grams
  • c. Sodium 131 mmol, Chloride 131 mmol, Glucose 40 grams
  • d. Sodium 70 mmol, Chloride 70 mmol, Glucose 400 grams
  • e. Sodium 131 mmol, Chloride 131 mmol, Glucose 400 grams

28 Injury or inflammation result in:

  • a. A decrease in capillary permeability and an increase in plasma albumin concentrations
  • b. A decrease in capillary permeability and an increase in interstitial albumin concentrations
  • c. An increase in capillary permeability and an increase in plasma albumin concentrations
  • d. An increase in capillary permeability and a decrease in plasma albumin concentrations
  • e. No change in capillary permeability and a decrease in plasma albumin concentrations

29 Which of the following fluid prescriptions is most appropriate for a 70-kg man on the first postoperative day after a standard right hemicolectomy:

  • a. 3-Litres 0.9% Sodium Chloride with a total of 70 mmol Potassium
  • b. 3-Litres 0.9% Sodium Chloride with a total of 120 mmol Potassium
  • c. 2.5-Litres 5% Dextrose with a total of 70 mmol Potassium
  • d. 1-Litre Dextrose saline and 1.5-Litres 0.5% Dextrose with a total of 70 mmol Potassium
  • e. 2-Litres 4% Dextrose/0.18% Saline with a total of 70 mmol Potassium

30 Which one of the following statements concerning body compartments is true?

  • a. Sodium is the major intracellular cation
  • b. Potassium is the major extracellular cation
  • c. Chloride is the major intracellular anion
  • d. Sodium is the major extracellular cation
  • e. Albumin is the major intracellular anion

31 Which of the following statements concerning the anion gap is true?

  • a. The anion gap always increases in a metabolic acidosis
  • b. The anion gap is equal to the concentration of (Sodium + Magnesium) – (Chloride + Phosphate)
  • c. The normal range for the anion gap is 30-40 mmol/L
  • d. The anion gap always increases in a metabolic alkalosis
  • e. The anion gap is equal to the concentration of (Sodium + Potassium) – (Chloride + Bicarbonate)

32 Advantages of using colloids include:

  • a. A larger volume of colloid is required to achieve the same plasma volume expanding effects as crystalloids
  • b. Colloids protect platelet function
  • c. There is less risk of anaphylaxis with using colloids
  • d. Colloids are cheaper to use than crystalloids
  • e. Smaller volumes of colloid are needed to resuscitate patients (compared with crystalloids)

33 An arterial blood gas profile of pH 7.21, PaCO2 6.5 kPa, PaO2 15 kPa, Bicarbonate 15 mmol/L, Base Excess -10 mmol/L implies which of the following physiological conditions:

  • a. Mixed metabolic and respiratory acidosis without compensation
  • b. Primary metabolic acidosis with respiratory compensation
  • c. Primary metabolic acidosis without compensation
  • d. Mixed metabolic and respiratory acidosis with partial compensation
  • e. Primary respiratory acidosis with metabolic compensation

34 Consequences of excess 0.9% sodium chloride infusion include:

  • a. Renal tubular acidosis
  • b. An increase in plasma oncotic pressure
  • c. Metabolic alkalosis
  • d. A decrease in the strong ion difference
  • e. Hyponatraemia

35 Concerning the use of fluids for acute resuscitation of critically ill surgical patients:

  • a. 5% dextrose is the ideal resuscitation fluid
  • b. The aim is to restore intracellular volume
  • c. Larger volumes of hypertonic saline must be used to achieve the same plasma expanding effects as 0.9% saline
  • d. The recommended fluid in daily practice is 20% albumin
  • e. The goal of fluid replacement is to improve microcirculatory perfusion

36 The following statements about central venous pressure (CVP) monitoring are true:

  • a. CVP is directly related to blood volume
  • b. Following a fluid challenge, a persistent rise in CVP implies further volume expansion is required
  • c. CVP is an accurate marker of left-heart function
  • d. CVP is inversely related to blood volume
  • e. Following a fluid challenge, a declining CVP implies further volume expansion is required

37 The average sodium deficit in moderate diabetic ketoacidosis is:

  • a. 100-120 mmol
  • b. 500-600 mmol
  • c. 280-350 mmol
  • d. >700 mmol
  • e. <100 mmol

38 The average potassium deficit in severe diabetic ketoacidosis is:

  • a. <100 mmol
  • b. 120-220 mmol
  • c. >700 mmol
  • d. 280-350 mmol
  • e. >350 mmol

39 The average sodium deficit in a diabetic patient with hyperosmolar nonketotic state is:

  • a. 100-150 mmol
  • b. 150-220 mmol
  • c. 350-700 mmol
  • d. >700 mmol
  • e. <100 mmol

40 Excess salt and water administration:

  • a. Is inevitable during fluid resuscitation for shock
  • b. Has little consequence on outcome after surgery
  • c. Improves gastrointestinal function
  • d. Causes oedema when there is a positive fluid balance of 1 L
  • e. Should usually be treated with diuretics

41 In older adults admitted to hospital:

  • a. Hyponatraemia is common
  • b. Salt and water excess is more common than deficit
  • c. Hypokalaemia is more common than hyponatraemia
  • d. Fluid balance problems are rare
  • e. Skin turgor is a good marker of fluid balance status

42 Refeeding syndrome:

  • a. Is associated with a decrease in serum calcium
  • b. Can lead to irreversible neurological damage
  • c. Is not related to the degree or duration of starvation
  • d. Is caused by excessive energy intake during refeeding and not by excess of any one particular nutrient
  • e. Is easier to treat than prevent

43 Salt and water deficit can cause:

  • a. Pre-renal acute kidney injury
  • b. A fall in haematocrit
  • c. Hypokalaemia
  • d. Convulsions
  • e. Hypoparathyroidism

44 Hypomagnesaemia can cause:

  • a. Hypercalcaemia
  • b. Muscle rigidity
  • c. Hypoparathyroidism
  • d. Neuromuscular irritability
  • e. Diarrhoea

45 Hypophosphataemia:

  • a. Is a feature of the metabolic response to injury
  • b. Can be secondary to hypokalaemia
  • c. Is a feature of the refeeding syndrome
  • d. Can cause hypernatraemia
  • e. Can produce constipation

46 Which of the following is a feature of Stage 1 acute kidney injury?

  • a. Increase in serum creatinine by ≥26 μmol/L within 12 h or increase in serum creatinine

≥1.5-1.9× baseline or a urine output <0.5 ml/kg/h for >2 consecutive hours

  • b. Increase in serum creatinine by ≥26 μmol/L within 24 h or increase in serum creatinine

≥2-2.9× baseline or a urine output <0.5 ml/kg/h for >6 consecutive hours

  • c. Increase in serum creatinine by ≥26 μmol/L within 24 h or increase in serum creatinine

≥1.5-1.9× baseline or a urine output <0.5 ml/kg/h for >6 consecutive hours

  • d. Increase in serum creatinine by ≥26 μmol/L within 24 h or increase in serum creatinine

≥1.5-1.9× baseline or a urine output <0.5 ml/kg/h for >12 consecutive hours

  • e. Increase in serum creatinine by ≥26 μmol/L within 12 h or increase in serum creatinine

≥1.5-1.9× baseline or a urine output <0.3 ml/kg/h for >6 consecutive hours

47 Which of the following is not a cause of intrinsic acute kidney injury:

  • a. Ischaemia-reperfusion injury
  • b. Intravenous iodinated contrast media
  • c. Myeloma
  • d. Cholesterol embolisation
  • e. Retroperitoneal fibrosis

48 During the de-escalation phase of the treatment of shock:

  • a. Intravenous starches are the treatment of choice
  • b. High dose inotropes may be necessary
  • c. Renal replacement therapy may be necessary to achieve a negative fluid balance
  • d. Fluid replacement volume should be 1 L more than the urine output
  • e. 10 mg frusemide should be added to every litre of 0.9% saline prescribed

49 Chronic kidney disease:

  • a. Is defined by an eGFR less than 60 ml/min/1.73m2, by the presence of markers of kidney damage (structural or albuminuria), or both, for at least 3 months
  • b. The diagnosis of chronic kidney disease requires two serum creatinine values measured at least 180 days apart
  • c. Diabetes mellitus accounts for 10% of all cases of chronic kidney disease
  • d. Treatment should aim to maintain blood pressure <150/90 mm Hg
  • e. Anaemia in advanced chronic kidney disease is commonly due to blood loss

50 Both fluid deficit and fluid overload can result in:

  • a. Hyperchloraemic metabolic acidosis
  • b. Raised intraabdominal pressure
  • c. Splanchnic oedema
  • d. Mitochondrial and endothelial dysfunction
  • e. Oculogyric crisis

51 Hyponatraemia is most commonly caused by:

  • a. Sodium loss or deficit
  • b. The metabolic response to injury
  • c. Starvation
  • d. Excess water intake
  • e. Antihypertensive drugs

52 ECG changes in hyperkalaemia include all of the following except:

  • a. Prominent U waves
  • b. Tall, tented T waves
  • c. Flattened P waves
  • d. Widening of the QRS complex
  • e. Ventricular fibrillation

53 In patients with acute kidney injury, early referral is recommended for all of the following except:

  • a. Serum creatinine ≥3 × baseline value
  • b. pH <7.15
  • c. methanol poisoning
  • d. bloody diarrhoea, haemolysis and thrombocytopaenia
  • e. Urine output <0.5 ml/kg/h for 3 consecutive h

54 Hyperchloraemic acidosis can cause all of the following except:

  • a. Oliguria
  • b. Increased glomerular filtration rate
  • c. Increased renal afferent arteriolar resistance
  • d. Decreased urinary sodium excretion
  • e. Release of adenosine

55 Which of the following is correct with regards to osmolality?

  • a. It is measured in mOsm/kg
  • b. It is the sum of mmol of ions divided by the volume of fluid
  • c. Osmolality is usually greater than osmolarity
  • d. The osmolality of plasma takes into account albumin concentration
  • e. Lactate is a major contributor to serum osmolality

56 Which of the following can cause metabolic alkalosis?

  • a. Infusion of large volumes of 0.9% saline
  • b. Cushing’s syndrome
  • c. Hypovolaemic shock
  • d. Metformin
  • e. Chronic kidney disease

57 Which of the following drugs can raise the serum potassium concentration?

  • a. Insulin
  • b. Angiotensin converting enzyme inhibitors
  • c. Thiazide diuretics
  • d. Salbutamol
  • e. Hydrocortisone

58 The normal anion gap is:

  • a. -2 to 2 mmol/L
  • b. 0-3 mmol/L
  • c. 5-11 mmol/L
  • d. 12-17 mmol/L
  • e. 20-25 mmol/L

59 Which of the following body fluid compartments has the largest volume of water?

  • a. The interstitial space
  • b. The intracellular space
  • c. The extracellular space
  • d. The intravascular space
  • e. Lymph

60 Which of the following control water homeostasis?

  • a. Carotid sinus baroreceptors
  • b. Atrial natriuretic peptide
  • c. Brain natriuretic peptide
  • d. Renin-angiotensin-aldosterone system
  • e. Osmoreceptors in the hypothalamus

61 The hour-1 bundle for initial resuscitation for sepsis and septic shock include all of the following except:

  • a. Measuring serum lactate concentration
  • b. Intravenous crystalloid administration @ 30 ml/kg for hypotension
  • c. Start vasopressors in hypotensive patients to maintain systolic blood pressure >100 mm Hg
  • d. Obtaining blood cultures before administering antibiotics
  • e. Administration of broad spectrum intravenous antibiotics

62 Which of the following is not advisable in the treatment of haemorrhagic shock?

  • a. Supplementary oxygen should be given to maintain oxygen saturation at >95%
  • b. Administer an initial, warmed fluid bolus of 6% hydroxyethyl starch. The usual initial dose is 1 L for adults
  • c. Early administration of blood products at a low ratio of packed red blood cells to plasma and platelets can prevent the development of coagulopathy and thrombocytopenia
  • d. Definitive control of haemorrhage and restoration of adequate circulating volume
  • e. Insertion of a nasogastric tube

63 Which of the following is true?

  • a. The sodium content of sweat is similar to that of plasma
  • b. High volume nasogastric aspirates can lead to a hyperkalaemic acidosis
  • c. The potassium concentration in small intestinal secretions is 5-10 mmol/L
  • d. Pancreatic juice has a bicarbonate concentration of 80-100 mmol/L
  • e. The sodium concentration in bile is half than in plasma

64 Which of the following is a risk factor for salt and water depletion in the older adult?

  • a. Living alone and social deprivation
  • b. Liver disease
  • c. Obesity
  • d. Congestive cardiac failure
  • e. Cold weather

65 Which of the following medications can cause hyperkalaemia in the elderly?

  • a. Frusemide
  • b. Thiazide diuretics
  • c. Salbutamol
  • d. Angiotensin converting enzyme inhibitors
  • e. Senna

66 Which of the following is true regarding free water?

  • a. Most of the free water in the postoperative period is provided by intravenous administration of 0.9% saline
  • b. 5% dextrose does not provide any free water
  • c. Most of the free water in the postoperative period is provided by intravenous administration of Hartmann’s solution
  • d. Free water clearance is greater in response to hypertonic fluid administration than to hypotonic fluid administration
  • e. Free water clearance is defined as the volume of plasma that is cleared of solute-free water per unit time

67 Which of the following is not true about estimated glomerular filtration rate?

  • a. It is a mathematically derived value
  • b. It is based on the serum creatinine concentration, age, sex and race
  • c. It can also be calculated based on the blood urea concentration, age, sex and race
  • d. It is expressed in ml/min/1.73m2
  • e. The eGFR value approximates to the percentage of kidney function

68 Which is not true about the passive leg raising test?

  • a. It is best undertaken by lying the patient flat and passively raising their legs to 15°
  • b. It is a bedside method to assess likely response to fluid administration
  • c. If the patient develops dyspnoea, it indicates that the patient may be fluid overloaded
  • d. Signs of haemodynamic improvement (e.g. rise in blood pressure, decrease in tachycardia, improved peripheral perfusion) at 30–90 seconds suggest an intravascular volume deficit likely to respond to intravenous fluids
  • e. It may be undertaken with the patient initially semi-recumbent and then tilting the entire bed through 45°

69 Which of the following blood laboratory values is not in the normal range?

  • a. Bicarbonate 24-32 mmol/L
  • b. Magnesium 0.8-1.2 mmol/L
  • c. Lactate 0.6-1.8 mmol/L
  • d. Chloride 95-105 mmol/L
  • e. Ionised calcium 2.2-2.6 mmol/lL

70 If you had to administer 2 litres of fluid over 24 hours, what rate would you set the infusion pump at?

  • a. 100 ml/h
  • b. 83 ml/h
  • c. 110 ml/h
  • d. 90 ml/h
  • e. 60 ml/h

71 Which of the following medicines is not normally metabolised and/or excreted by the kidneys:

  • a. Penicillins
  • b. Cehpalosporins
  • c. Vancomycin
  • d. Fractionated heparin
  • e. Clindamycin

72 Clinical features of chronic kidney disease include all of the following except:

  • a. Polycythaemia
  • b. Restless legs
  • c. Bone pain
  • d. Muscle weakness
  • e. Prutitus

73 Patients scheduled for elective surgery should be:

  • a. Starved for 12 hours before the induction of anaesthesia
  • b. Starved for 8 hours before the induction of anaesthesia
  • c. Allowed to eat for up to 4 hours and drink clear liquids for up to 1 hour before the induction of anaesthesia
  • d. Starved for 24 hours before the induction of anaesthesia
  • e. Allowed to eat for up to 6 hours and drink clear liquids for up to 2 hours before the induction of anaesthesia

74 Salt and water overload after gastrointestinal surgery can lead to:

  • a. Increased mesenteric blood flow
  • b. Anastomotic dehiscence due to impaired wound healing
  • c. Improved venous return
  • d. Increased intestinal contractility
  • e. Intestinal intramucosal alkalosis

75 The aims of postoperative fluid therapy include all of the following except:

  • a. Avoidance of excessive fluid administration
  • b. Achieving a state of as near zero fluid balance as possible
  • c. Early resumption of oral fluids and diet
  • d. Providing parenteral or enteral nutrition for the first five to seven days
  • e. Supplementing patients with intravenous fluids if oral intake is inadequate

ANSWERS TO MULTIPLE CHOICE QUESTIONS

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