Mod 8 ARDS Flashcards
What happens when there is increased membrane permeability?
Fluid shifts and spilling out into the alveoli
What happens when there is a loss of surface area for gas exchange in ards?
- what causes it?
Caused by atelectasis, causing blockages.
- Meaning there is increased intrapulmonary shunting
Berlin criteria: Timing
Main aims of supportive care for ARDS?
Oxygen therapy
Most important principle of ARDS treatment
Identify the underlying causes!
Mech Vent approach for ARDS on a ventilator?
High PEEP/ Low FiO2
or
Low PEEP and High FiO2
Lung protective strategies as well (Pplat < 30cmH2O)
Extra treatment on top of O2 + PEEP
Prone positioning
- helps to improve oxygenation [V/Q]
- Used for severe patients with P/F ratio <150
Extra lung protective strategies
vv-ECMO for severe patients to help with gas exchange and improve oxygenation
- usage of NMBA’s can help with oxygenation (helps lower oxygen uptake)
What is the development time of ARDS?
Acute resp. disease that develops within 7 days of onset.
what symptoms are typical w/ARDS?
- Diffuse inflammatory lung injury
- Increased membrane permeability
- Loss of SA for gas exchange
- Bilateral Opacities on CxR, leading to hypoxemia
The Berlin criteria for ARDS comprises of [4]?
- Timing
- Imaging
- Origin of edema
- Oxygenation
Berlin criteria for ARDS: What’s timing?
Within one week of a known clinical insult or new/worsening resp.symptoms
Berlin criteria for ARDS: Imaging
Bilateral opacities
- not fully explained by effusions, local/lung collapse or nodules
Berlin criteria for ARDS: Origin of Edema?
- Resp. Failure not fully explained by cardiac failure or fluid overload
- Requires an objective assessment (echo) to exclude hydrostatic edema if risk factors are not present
Berlin criteria for ARDS: Mild ARDS
PaO2/FiO2 = P/F Ratio
[300 - 200] w/PEEP > 5cmH2O
Berlin criteria for Moderate ARDS
P/F Ratio < [200-100] w/PEEP > 5
Berlin criteria for Severe ARDS
P/F Ratio < 100
w/PEEP > 5 cmH2O
How often should the ARDS criteria be reevaluated?
24 hrs after onset
- Pt persistence is essential for the correct diagnosis of ARDS
Is the incidence of ARDS known?
nope
Annual mortality rate for ARDS?
Estimated to be > 30000 pts per year
Mortality rates in very severe ARDS
25 - 45%
ARDS is believed to cause what to the body?
bonus
- what are 6 complications that can be seen with ARDS?
systemic manifestations; leading to multi-organ failure/death
such as:
- severe difficulty in breathing (Leads to decreased oxygenation of the blood and reduced delivery of oxygen to the body’s tissues.)
- Systemic inflammation (cause damage to other organs)
- Hypoxemia (decreased arterial O2 lvls)
- Alveolar damage (fluid accumulation)
- Increased WOB -> fatigue -> resp. muscle failure
- Reduced lung compliance (difficult to expand and contract)
ARDS may be caused by which 2 main etiologies?
- Direct lung injury
- Indirect lung injury
What is a direct lung injury? (5)
- Pneumonia aspiration
- Toxic inhalation
- Chest/lung trauma
- near drowning
- Aggressive mech. ventilation
What is indirect lung injury
- Sepsis
- Burns
- non-thoracic trauma
- Massive blood transfusion
- drug overdose
What is the leading cause of ARDS?
Pneumonia and Sepsis
ARDS pathology is related to what 3 traits?
hint
- what is affected on the body?
- Altered pulmonary capillary permeability (increased)
- Atelectasis
- Increased intrapulmonary shunt
All associated w/impaired gas exchange
The histological correlation of ARDS consists of diffuse alveolar damage consisting of what conditions?
- Atelectasis
- intra-alveolar hemorrhage
- intra-alveolar and interstitial edema
- hyaline membrane formation
ARDS progresses via 3 distinct phases
- Exudative phase
- fibroproliferative phase
- Fibrotic phase
ARDS Pathophysiology: Exudative phase traits?
- Innate immune cell mediated cell damage (Severe inflammation)
- Altered composition/quantity of pulmonary surfactant
- Bacterial or viral infection
- Shock
- combined resp. and metabolic acidosis
What are aspects of cell-mediated cell damage bc of ARDS?
- think severe inflammation
- Impaired fluid clearance
- Influx of neutrophils, macrophages, lymphocytes into the alveoli
- exudative of plasma and debris into alveolar spaces
- unregulated release of potent cytosine mediators and immune cells enter the lungs
ARDS Pathophysiology: fibroproliferative phase traits
edit/add stuff
slide 12
- Lung repair processes trying to restore alveolar functions
-
Look at ARDS.net via interventions link
How do you know if progression of a disease pathology is indicative of ARDS?
ARDS = Compliance issue.
- if there is a decrease in compliance.
Secretions in the ETT is indicative of what type of problem?
Resistance
How do you know if a pneumothorax has occured?
Pneumo is a sudden development.
