ARF/ ARDS Flashcards
hypoxia vs hypoxemia
hypoxemia = low O2 in blood (PaO2<80 mm Hg, <60 if chronic lung disease)
hypoxia= low O2 in tissues
ventilation vs perfusion
• Ventilation (V) AIR MOVEMENT
• Perfusion (Q) BLOOD FLOW
what happens when ventilation and perfusion are mismatched?
When they do not match in the lung (or an area of the lung
)–> Respiratory failure
is a PE a perfusion or ventilation issue?
perfusion
is pneumothorax a perfusion or a ventilation issue?
ventilation
what causes respiratory failure- ventilation, oxygenation, both?
–Ventilation or
–Oxygenation or
–Both
what happens in ventilation failure? is the perfusion normal or abnormal?
The problem is with Air Movement
–Inadequate air movement in alveoli
• Perfusion is normal
• Air cannot move in and out of the lungs enough
• Oxygen cannot get to the alveoli
• CO2 is stuck in the alveoli
• Blood is flowing by to pick up oxygen but it is a wasted trip…There isn’t enough O2 in the alveoli to pick up (only CO2)
causes of ventilation failure?
• Physical Problems with chest and lungs
• Injury or failure of the respiratory control center
• Inability to control function of respiratory muscles
causes of ventilation failure
• Drug overdose
• Rib Fractures
• Pneumothorax
• Airway obstruction
• Paralysis
• Brain injury
• Spinal Cord injury
• Physical Problems with chest and lungs
• Injury or failure of the respiratory control center
• Inability to control function of respiratory muscles
causes of perfusion failure
• Pulmonary emboli
• Pneumonia
• Pulmonary edema
causes of combined oxygen and perfusion failure?
• Leads to worse respiratory failure/ hypoxemia than ventilation or perfusion failure alone
• Abnormal lungs seen with
–Chronic bronchitis
–Asthma
–Cystic fibrosis
–Emphysema
–ARDS
assessment findings for acute resp. failure?
Heart rate? pulses? breathing style? bp? mental status?
• Dyspnea
• Orthopnea
• Respiratory Pattern
• Lung Sounds
• Pulse Oximetry
• ETCO2 (end tidal co2 monitoring- Co2 breathing out at end of breath, 35-45)
• ABG’s
• Restlessness, agitation, irritability
• Confusion
• Change in LOC
• Hypotension
• Bradycardia
• Weak pulses
interventions for acute resp. failure?
Oxygen, Oxygen, Oxygen
• Treat underlying cause
• Positioning
• Assist with anxiety
• Energy conserving measures
ARDS causes (3 main categories)
(ARF, systemic inflammation, lung injury)
• Acute Respiratory Failure with
–Reduced Compliance (lungs are getting stiff/rigid- can lead to fibrosis)
–Dyspnea
–Pulmonary edema
–Diffuse pulmonary infiltrates
–Severe Hypoxemia
• Often associated with another disease process that may cause acute lung injury (ALI) from systemic inflammatory response
–Sepsis
–Pancreatitis
–Trauma
–Transfusions
• Also caused by direct injury to lungs
–Aspiration
–Pneumonia
pathophysiology of ARDS
With ARDS, the alveolar-capillary membrane become more permeable
• This allows fluid, waste and protein mediators into alveoli
• Reduced production of surfactant (reduced compliance)
• ALVEOLAR ARE UNABLE TO EXCHANGE GAS
ARDS assessment findings
• Increased work of breathing
• Loud breathing- adventitious breathing sounds
• Cyanosis
• Use of accessory muscles for breathing
• Confusion
ards diagnostics (4)
• ABG
• Chest X-ray
• Sputum culture – bacterial component for underlying thing we could treat like pneumonia
• PF ratio (PaO2, FiO2 ration) <300 = indicative ARDS
why do a sputum culture with ards?
test for bacterial component for underlying thing we could treat like pneumonia
PF Ratio < _____ = indicative of ARDS
<300
Why do we give ARDS patients PEEP?
◦ alveoli collapsed at end of respiration in ARDS, give a little bit of positive pressure prevents collapse of alveoli
◦ a normal person does not have collapsed alveoli at end of breath becuase we have the surfactant we need to keep them open
ARDS intervention
Peep
mechanical ventilation
sedation
paralytics
analgesics
proning
mobility
ecmo
iv fluid- maybe
enteral nutrition
why put ARDS patients in prone position?
◦ more alveoli in posterior portion of lungs, proning allows for their expansion
