Ventilation Flashcards
Type 1 RF
Hypoxaemic
Type 2 RF
Hypoxia and hypercapnia
Type 3 RF
Perioperative
Type 4 RF
Shock
Indications for CPAP
Neonates
OSA
Obesity
Extubation
Heart failure (pulm oedema)
Physiological effects of CPAP
Reduces pulmonary vascular resistance
Reduce LV preload
Reduce venous return
Improved FRC
Reduces atelectasis
Improve VQ mismatch
Improve surface area
Indications for BIPAP
T2RF / COPD
Asthma (controversial)
Cardiogenic pulm oedema (not routine)
Post intubation
Chest wall trauma
Neuromuscular diseases
Contraindications for NIV/bipap
Facial trauma
#BOS (pneumocephalus)
Airway protection needed
Makes tolerability
Apnoea
Benefits of NIV. V Invasise
Avoids intubation
Quick and easy
Lower infection risks
Less drugs
Easier to wean
Allows communication
Eating and drinking
Lung protective ventilation considerations
Mode irrelevant
Minimise volume and pressure
Tv 6-8ml / kg
Optimise PEEP
Plateau pressures below 30
Ventilator basics
Control - volume, pressure, dual
Trigger - machine or pt
Cycling - how vent switches to exp
(Time, flow, pressure)
SIMV
Synchronised intermittent mandatory ventilation
Volume or pressure control
Cycled time or pt
Permits along breathing
CIMV
Continuous mandatory ventilation
Volume or pressure
Cycled time
Prevents spont breathing
APRV
Airway pressure release ventilation
High levels of peep with times cycle releases
Maintains recruitment
Encourages spont breathing
P high
T high
P-high = highest level of pressure
T-high = time in seconds spent at pressure
HFOV
High frequency oscillation ventilation
Increases mortality
Dysynchrony
Pts demand not met by ventilator
Fighting the ventilator
Causes? Pain? Anxiety? Awareness?
Double triggering
Reflects inadequate machine support:
Increase inspiratory time or convert to pressure support
ARDS statistics
17-34 per 100,000
10-15% of ITU admissions
Mortality 40%
Describe ARDS
Spectrum of poorly understood conditions
Acute (<1 week from insult) diffuse, imagine bilateral opacities not explained by effusion or HF, mild moderate severe
ARDS risk factors
Pneumonia
Aspiration
Drowning
Inhalation injury
Indirect: Sepsis, trauma, pancreatitis, burns
ARDS pathophysiological consequences
VQ mismatch
Reduced lung compliance
Pulmonary hypertension
ARDS treatment
Treat underlying cause
Protective strategy
General ITU care
ARDS General points for management
Deceleration flow (VC auto flow)
Optimum peep
Low tv
Plat pressure <30
Permissive hypercapnia (ph > 7.2)
Refractory hypoxia: prone, NMB, ECMO
Asthma immediate treatment
Oxygen, salbutamol, atrovent, steroids, magnesium, rule out TPx, intubation
Features of severe asthma
Peak exp flow <33-50%
Can’t complete sentences
Resps > 25/min
Hypoxia
Normal paco2
Silent chest
Hotn
Exhaustion or low gcs
Considerations when intubating asthmatics
Relative hypovolaemia
Anticipate CVS collapse (neg v pos pres)
Ketamine
Avoid opioids
How to assess intrinsic peep
Auto peep
(Bronchospasm)
How to asses intrinsic peep
Expiratory hold on vent
Extremists asthma management
ECMO
Ket infusion
Disconnect from vent manually decompress
Thoracostomies
