Week 5 - I - Renal Pharmacology and IV Fluid maintenance (Adults/Children(Holliday-Segar)/Neonates

Question 1

behaviour of a drug with regard to absorption, distribution, metabolism and elimination What is this?

Answer 1

Pharmacokinetics

Question 2

When is renal elimination reduced?

Answer 2

In renal impairment

Question 3

What is the diagnosis of this man?

Answer 3

The man has acute left ventricular failure

Question 4

What factors from the drug perspective view have led to the acute left ventricular failure?

Answer 4

The NSAIDs has caused sodium retention as it cause vasoconstriction of the afferent arteriole His diuretic being stopped due to gout has also led to the build up of fluid causing increased BP (verapamil causing depression of myocardial function - apparently - decreases force of contraction

Question 5

What does this show that the patient has? Question: 2) What are the possible causes of the biochemical results in this man?

Answer 5

Acute kidney injury The patinet has background chronic kidney disease secondary to hypertension and his diabetes Aspirin has induced renal impairment

Question 6

How would it be checked if the patient has long standing CKD with an acute attack or if it is just acute kidney injury?

Answer 6

Do an ultrasound scan

Question 7

serum biochemistry shows the following: Na+ 119mmol/L (NR 135-147 mmol/L) K+ 6.8 mmol/L (NR 3.5-4.9 mmol/L) Creat 665 micromol/L (NR 60-98 mol/L) What is the most worrying facotr here?

Answer 7

The elevated potassium

Question 8

You admit him to hospital asap His admission blood gas: pH 7.20 (NR 7.35-7.45) pO2 14.0 kPa (NR 12.0-14.7) pCO2 2.1 kPa (NR 4.7-6.1) Bic 14 mmol/L (NR 24-30) What does this ABG show?

Answer 8

This shows metabolic acidosis with respiratory compensation

Question 9

Where would metabolic acidosis be on a Davenport diagram?

Answer 9

Would be in the bottom left of the diagram

Question 10

What is the emergency treatment of the hyperkalaemia?

Answer 10

10ml 10% calcium gluconate over 10 minutes 10units short acting Insulin (ActRapid) in 50ml 50% dextrose over 10 minutes 10mg salbutamol nebulised

Question 11

What would be done for the acute renal failure?

Answer 11

Catheterise the patient and give saline

Question 12

What could be causing her proteinuria? What could be causing her hypertension?

Answer 12

Proteinuria causes - penicillamine causing glomerulonephritis Amyloid secondary to rheumatoid arthritis Hypertension causing glomerulosclerosis Diclofenac could be causing the hypertension

Question 13

What action would this lady required?

Answer 13

BP control - ACEinhibitor

Question 14

A blood count six weeks later shows her platelet count to be 100 x 109/L (NR 150-500 x 109/L) Questions: 4) What is the likely cause?

Answer 14

Penicillamine - causes mylosuppresion Stop penicillamine prescription and restart when platelet recover

Question 15

What type of glomerulonephritis is penicillamine associated with?

Answer 15

Membranous nephropathy

Question 16

What is a diazide tablet?

Answer 16

This is a combination of a thiazide diuretic and potassium sparing diuretic (hydrochlorothiazide and triamterene)

Question 17

1) What has happened to him and why?

Answer 17

Salt and water loss due to the triple diuresis

Question 18

Investigations: Creatinine is 350 mol/L, K+ 5.6 mmol/L Urine osmolality 520 mosm/kg, Urine sodium 16 mmol/L What type of acute kidney injury has the man entered?

Answer 18

Prerenal failure

Question 19

A year later, he suffers an attack of gout for which his GP prescribes diclofenac Two weeks later his breathlessness increases, his ankles swell and his BP rises His creatinine also increases to 200micromol/L What has happened?

Answer 19

The NSAID has caused sodium retention leading to an increased blood pressure and an increased serum creatinine as the GFR has decreased

Question 20

If a patinet presents with a GFR of 0 , what does this mean for their urine output?

Answer 20

Patient would be anuric - no urine is produced

Question 21

IV FLUID MAINTENANCE - 4th year stuff What is the type of fluid and what range is the sodium in this fluid that is given as a bolus and as maintenance fluids to patients who require IV fluid therapy?

Answer 21

Initially use isotonic crystalloids that contain sodium in range 131 - 154 mmol/litre * Saline is an example of an isotonic crystalloid fluid

Question 22

IV FLUID MAINTENANCE - ADULTS What is the initial bolus of fluid given to an adult who requires fluids and over how long? When does this change?

Answer 22

* Give 500ml bolus of fluid to an adult over 15 minutess * If heart failure, give 250 ml bolus of fluid over 15 minutes

Question 23

What is the maintenance fluids given to an adult requiring fluids? What if the adult has underlying cardiac problems?

Answer 23

Give 25-30ml/kg/day for an adult If the patient has underlying cardiac problems give 20-25 ml/kg/day for an adult

Question 24

IV FLUID MAINTENANCE - CHILDREN AND YOUNG PEOPLE What is the initial bolus of fluid given to a child / young person who requires fluids and over how long?

Answer 24

Give a bolus of 20 ml / kg over 10/15 minutes

Question 25

What is the maintenance fluids regime carried out in children / young people? - utlises the Holliday Segar Formula (both ml/kg/day and ml/kg/hr)

Answer 25

100:50:20

• * 100ml/kg/day for first 10kg of weight
• * 50ml/kg/day for second 10kg of weight
• * 20ml/kg/day for any additional weight over 20kg

4:2:1

• * 4ml/kg/hr for first 10kg of weight
• * 2ml/kg/hr for second 10kg of weight
• * 1ml/kg/hr for any additional weight over 20kg

Question 26

What would the maintenance fluid requirements be for a 30kg child?

(give answer using both ml/day and ml/hr)

Answer 26

• * 100ml/kg/day for first 10kg - 1000ml
• * 50ml/kg/day for second 10kg - 500ml
• * 20ml/kg/day for above 20kg - 200ml
  
  • Total = 1700ml/day
• * 4ml/kg/hr for first 10kg - 40ml
• * 2ml/kg/hr for second 10kg - 20ml
• * 1ml/kg/hr for above 20kg - 10ml
  
  • Total = 70ml/hr (70 x 24 = 1680ml/day so equations match)

Question 27

What fluid limit do male and female children/young persn rarely need more than?

Answer 27

Male children rarely need more than 2500ml in a 24 hour period (would need to be a 70kg male child/young person) Female children rarely need more than 2000ml in a 24 hour period (would need to be a 45kg female child/young person)

Question 28

IV FLUID MAINTENANCE - NEONATES What is the initial bolus of fluid given to a neonate who requires fluids and over how long?

Answer 28

Give an initial bolus of 10-20 ml/kg over 10/15 minutes

Question 29

What is the maintenance fluid regimen carried out in a neonate for: * Day 1 * Day 2 * Day 3 * Day 4 * Day 5-28

Answer 29

• Day 1 - 50-50ml/kg/day
• Day 2 - 70-80ml/kg/day
• Day 3 - 80-100ml/kg/day
• Day 4 - 100-120ml/kg/day
• Day 5-28 - 120-150 ml/kg/day