Fluid and Nutrition

Question 1

How much Na and K should we take In each day?

Answer 1

150 sodium

100 potassium

Question 2

How much of human body is water?

Intracellular vs extracellular

Answer 2

in 70kg male = 42L

1/3rd is extracellular > 14L
2/3rds is intracellular > 28L

Question 3

What fluids are require for maintenance?

Answer 3

NaCl + KCL 20
the 2 x 5% dextrose with KCL 20

Gives total of 154 sodium and 60 K

Question 4

What is In a bag of Hartman’s?

Answer 4

131 Na
6 K 
111 Cl
29 Bicarb 
2.2 Ca

Question 5

What is the parklands formula?

Answer 5

resuscitation in burns = 4 x weight x % burns = mls given in first 24 hours

Question 6

How does colloid work?

Answer 6

Larger molecular weight = stays intravascular for lower = greater oncotic pressure

Question 7

Physiological change in response to surgery?

Answer 7

Rise in catecholamines, cortisol and aldosterone
These hormones = retention of Na and water

Fall In renal perfusion = renin = AT2 = aldosterone = Na reabsorption at expense of K and H+ = metabolic alkalosis

Stress mediated ADH release

Post op potassium will be raised due the excess from cell damage, which outweighs what kidney an excrete
You will also have a normal phase of oliguria and hypernatraemia

Question 8

Paediatric fluid replacement - what can’t we use outside neonatal period?

Answer 8

Saline / glucose mixtures, particularly 0.18% / glucose 4%

Question 9

Paediatric fluid replacement - Intraoperative fluid types?

Answer 9

Neonates = 10% glucose

Other kids = isotonic crystalloid

Question 10

Paediatric fluid replacement formula?

Answer 10

First 10kg = 100ml
Next 10 kg = 50ml
Subsequent Kg = 20ml

Question 11

Diarrhoea vs vomit electrolyte content?

Answer 11

Vomit = 120 sodium, 10 K
Diarrhoea = slightly lower sodium 40 K

Question 12

what counts as malnutrition?

Answer 12

BMI < 18.5
BMI < 20 with >5% weight loss in 3-6 months
>10% weight loss in 3-6 months

Question 13

If a patients a safe swallow following caesarean, gynae surgery or abdo surgery when can they feed?

Answer 13

within 24 hours ideally

Question 14

Different types of enteral feeds?

Answer 14

Polymeric liquid = Intact protein, starches and long chain FA’s
If unable to feed e.g. unconscious

Elemental = simple AA’s and sugars
- requires minimal bowel digestion = used of bowel resection

Disease specific
e.g. low protein In renal / liver failure, low fat in gallstones

Question 15

Indications for enteral feeding?

Answer 15

Catabolic
Coma / ITU
Malnutrition
Dysphagia e.g. stroke

Question 16

Indications for TPN?

Answer 16

Prolonged ileus
Short bowel syndrome
High output fistula
Severe Crohns / malnutrition / pancreatitis

Question 17

How to deliver TPN?

Answer 17

not via peripheral line due to high osmolality

Short term = CVC

Long term = Hickman / PICC

Question 18

Complications of TPN?

Answer 18

Line related = Arrhythmias, pneumothorax, infection, central venous thrombosis

Feed related = Villous atrophy of GIT, refeeding syndrome, long term use associated with fatty liver and deranged LFT’s

Question 19

Mechanism behind refeeding syndrome?

Answer 19

When starved you are catabolic = no insulin and intra cellular depletion of phosphate

The you start eating you have massive production of insulin and massive intracellular uptake of phosphate = phosphate <0.5

Question 20

Symptoms of hypophosphataemia ?

Answer 20

Rhabdomyolysis
Seizures 
Shock
Arrhythmias
Respiratory insufficiency