Intensive Care Medicine Flashcards
What is the mnemonic used to summarise the basic ICU care bundle
FASTHUG
F - Feeding A - Analgaesia S - Sedation T - Thromboprophylaxis H - Head Up U - Ulcer Prophylaxis G - Glucose control
Why is feeding the ICU patient vitally important
Protein Energy Malnutrition (Negative Nitrogen Balance) —> Impaired immunity + Sepsis and wound break down.
What are the methods of feeding in the ICU
Enteral
- NGT/NJT/Gastrostomy/Jejunostomy
Parenteral
- TPN
When is TPN indicated
Enteral nutrition is contraindicated
- Gastric stasis
- Intractable diarrhoea
- Malabsorption
How is TPN administered
CVL - with strict asepsis
What are the complications of TPN
Infection
Septicaemia
Hyperbilirubinaemia
Why is analgaesia paramount
The patient needs to be able to cough and expand the lungs.
Multimodal NB
Why is sedation required in the ICU and what is used for this?
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
What are the measures used for thromboprophylaxis in the ICU
- Prophylactic LMWH
- Graduated compression stockings
- Calf compression devices
Why are ICU patient’s nursed head up and how many degrees head up is required for these benefits?
15 degrees head-up
- Reduces aspiration of feeds (d/t passive regurgitation)
- Decreases incidence of ventilator associated pneumonia
What are the options for ulcer prophylaxis in the ICU
Sucralfate - 1 g 6hrly NGT
H2RA / PPI
What is the benefit of maintaining euglycaemia (4 -8 mmol/L)
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
What are the indications for mechanical ventilation
- Ventilation failure: PaCO2 increased with pH < 7.2
- Oxygenation failure: PaO2 < 11 kPa FiO2 > 0.4
- RICP and cerebral ischaemia (O2 demand : supply)
- 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
How is IPPV divided
Volume Control and Pressure Control
What is IMV vs SIMV
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.
What are the benefits of PEEP
- Increases FRC
- Improves pulmonary compliance
- Improves V:Q matching
- Improves oxygenation
What is CPAP
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
How does CPAP improve oxygenation and why is it beneficial
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.
What pressure is used for CPAP:
5 - 10 cmH20
When can a patient be weaned off the ventilator
Ease of weaning is inversely related to duration on the ventilator
- Disease prompted IPPV is reversed or under control
- Effective cough or VC > 1000 ml (±15ml/kg)
What are the principles of cardiovascular supportive care in the ICU
- Optimise preload and afterload
- Reverse myocardial depressants
- hypoxia
- hypercapnoea
- acidosis
- hypovolaemia
- hypocalcaemia - Inotrope
How does adrenalin effect its different receptors at high and low doses
Low doses - predominant beta effect - inotropy
High doses - predominant alpha effect - VC
Which receptors does noradrenalin predominantly act
alpha receptors –> vasoconstriction
Which receptors does dobutamine predominantly effect and what other important effect does it have
Beta mediated increase in CO
Decreases SVR
What is the mechanism of action of milrinone
Phosphodiesterase 3 inhibitor
–> Dilates pulmonary vasculature and useful in pulmonary hypertension.
Why is dopamine no longer used as an inotrope
Traditionally it was used for renal protection.
This has since been disproved and dopamine is no longer used.
What agents can be used to reduce afterload and reduce myocardial O2 demand.
When are these agents used clinically
Direct acting vasodilators
- Hydralazine
- Sodium Nitroprusside (SNP)
- Nitroglycerine (GTN) - most frequently used
Alpha blockers
- Phenoxybenzamine
- Phentolamine
Heart failure
Control of angina and reduce ischaemia
What are the indications for renal replacement therapy (RRT)
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
Define AKI
Acute Kidney Injury
One of the following
- Rise in SCr by > 26.5 in < 48 hrs
- SCr increase by 1.5 times baseline < 7 days
- UO < 0.5 ml/kg/hour for > 6 hours (exclude obstruction)
Define the RIFLE criteria
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
