Intensive Care Medicine

Question 1

What is the mnemonic used to summarise the basic ICU care bundle

Answer 1

FASTHUG

F - Feeding 
A - Analgaesia
S - Sedation
T - Thromboprophylaxis
H - Head Up
U - Ulcer Prophylaxis
G - Glucose control

Question 2

Why is feeding the ICU patient vitally important

Answer 2

Protein Energy Malnutrition (Negative Nitrogen Balance) —> Impaired immunity + Sepsis and wound break down.

Question 3

What are the methods of feeding in the ICU

Answer 3

Enteral
- NGT/NJT/Gastrostomy/Jejunostomy

Parenteral
- TPN

Question 4

When is TPN indicated

Answer 4

Enteral nutrition is contraindicated

• Gastric stasis
• Intractable diarrhoea
• Malabsorption

Question 5

How is TPN administered

Answer 5

CVL - with strict asepsis

Question 6

What are the complications of TPN

Answer 6

Infection
Septicaemia
Hyperbilirubinaemia

Question 7

Why is analgaesia paramount

Answer 7

The patient needs to be able to cough and expand the lungs.

Multimodal NB

Question 8

Why is sedation required in the ICU and what is used for this?

Answer 8

Inadequate pain control and anxiety has physiological sequelae.

Facilitation of mechanical ventilation
Decrease O2 demand
Impose day - night cycles

Prolonged benzos no longer used
Propofol infusions used

Question 9

What are the measures used for thromboprophylaxis in the ICU

Answer 9

1. Prophylactic LMWH
2. Graduated compression stockings
3. Calf compression devices

Question 10

Why are ICU patient’s nursed head up and how many degrees head up is required for these benefits?

Answer 10

15 degrees head-up

• Reduces aspiration of feeds (d/t passive regurgitation)
• Decreases incidence of ventilator associated pneumonia

Question 11

What are the options for ulcer prophylaxis in the ICU

Answer 11

Sucralfate - 1 g 6hrly NGT

H2RA / PPI

Question 12

What is the benefit of maintaining euglycaemia (4 -8 mmol/L)

Answer 12

Decreases septic complications
Decreases cardiac complications
Improves wound healing

Measure Hgt 2 hourly

insulin infusion commonly required due to hyperglycaemia related to the stress response

Question 13

What are the indications for mechanical ventilation

Answer 13

1. Ventilation failure: PaCO2 increased with pH < 7.2
2. Oxygenation failure: PaO2 < 11 kPa FiO2 > 0.4
3. RICP and cerebral ischaemia (O2 demand : supply)
4. Reduce work of breathing

RR > 30
pH < 7 .2 (with Increased PaCO2)
PaO2 < 8 kPa or < 11 kPA with FiO2 > 0.4

Exhaustion
Confusion
Severe shock

Question 14

How is IPPV divided

Answer 14

Volume Control and Pressure Control

Question 15

What is IMV vs SIMV

Answer 15

IMV - Intermittent Mandatory Ventilation
- Fixed number of fixed volume breaths are administered

SIMV - Synchronised Intermittent Mandatory Ventilation
- Mandatory ventilator breaths are synchronised with the patient’s own breaths to prevent stacking and hyper-inflating the lungs.

Question 16

What are the benefits of PEEP

Answer 16

1. Increases FRC
2. Improves pulmonary compliance
3. Improves V:Q matching
4. Improves oxygenation

Question 17

What is CPAP

Answer 17

This is continuous positive pressure applied during SPONTANEOUS VENTILATION to the expiratory side of the breathing circuit - requires tight fitting mask and an alert an co-operative patient.

Airway reflexes must be intact to prevent aspiration

Question 18

How does CPAP improve oxygenation and why is it beneficial

Answer 18

Baseline pressure in the upper airways is set above zero —> prevent alveolar collapse and atelectasis and recruit collapsed alveoli.

It will improve lung compliance and reduce the work of breathing by repositioning the lung on a more advantageous part of the lung compliance (Pressure - Volume) curve.

Its benefit is that it can be used in the ward so a patient does not need an ICU bed.

Question 19

What pressure is used for CPAP:

Answer 19

5 - 10 cmH20

Question 20

When can a patient be weaned off the ventilator

Answer 20

Ease of weaning is inversely related to duration on the ventilator

1. Disease prompted IPPV is reversed or under control
2. Effective cough or VC > 1000 ml (±15ml/kg)

Question 21

What are the principles of cardiovascular supportive care in the ICU

Answer 21

1. Optimise preload and afterload
2. Reverse myocardial depressants
   - hypoxia
   - hypercapnoea
   - acidosis
   - hypovolaemia
   - hypocalcaemia
3. Inotrope

Question 22

How does adrenalin effect its different receptors at high and low doses

Answer 22

Low doses - predominant beta effect - inotropy

High doses - predominant alpha effect - VC

Question 23

Which receptors does noradrenalin predominantly act

Answer 23

alpha receptors –> vasoconstriction

Question 24

Which receptors does dobutamine predominantly effect and what other important effect does it have

Answer 24

Beta mediated increase in CO

Decreases SVR

Question 25

What is the mechanism of action of milrinone

Answer 25

Phosphodiesterase 3 inhibitor | --> Dilates pulmonary vasculature and useful in pulmonary hypertension.

Question 26

Why is dopamine no longer used as an inotrope

Answer 26

Traditionally it was used for renal protection. | This has since been disproved and dopamine is no longer used.

Question 27

What agents can be used to reduce afterload and reduce myocardial O2 demand. When are these agents used clinically

Answer 27

Direct acting vasodilators 1. Hydralazine 2. Sodium Nitroprusside (SNP) 3. Nitroglycerine (GTN) - most frequently used Alpha blockers 1. Phenoxybenzamine 2. Phentolamine Heart failure Control of angina and reduce ischaemia

Question 28

What are the indications for renal replacement therapy (RRT)

Answer 28

Acidaemia pH < 7.2 (unresponsive) Electrolytes K > 7 (unresponsive) Intoxicants (Toxic alcohols, Li, ASA) Overload of fluid (Pulmonary oedema unresponsive) Oliguria < 200ml in 12 hour Uraemia Urea > 35 mmol/L - Uraemic encephalopathy - Uraemic pericarditis - Uraemic neuropathy - Uraemic myopathy - Uraemic coagulopathy

Question 29

Define AKI

Answer 29

Acute Kidney Injury One of the following 1. Rise in SCr by > 26.5 in < 48 hrs 2. SCr increase by 1.5 times baseline < 7 days 3. UO < 0.5 ml/kg/hour for > 6 hours (exclude obstruction)

Question 30

Define the RIFLE criteria

Answer 30

Criteria to classify the severity of acute kidney injury R - Risk SCr up by > 26.5 OR 1.5 - 1.9 x baseline UO < 0.5 ml/kg/hr for 6 - 12 hrs I - Injury SCr up by 2.0 - 2.9 times baseline UO < 0.5 for 12 - 24 hrs F - Failure SCR up by > 3 times baseline UO < 0.3 ml/kg > 24 hrs Anuria > 12 hrs L - Loss Needs RRT > 4 weeks E - End Stage Needs RRT > 3 months