2 Acute Respiratory Failure Flashcards
2 issues that can happen with gas exchange (examples)
Failure of either leads to what?
Ventilations:
-physical movement of air
(musculoskeletal/nervous system)
Perfusion/oxygenation (respiration):
-diffusion of I2 and CO2 between the alveoli
-membrane thickness
failure of either = respiratory failure
Acute respiratory failure
Definition
How does it occur
Altered gas exchange where resp system:
—fails to oxygenate
Or
—fails to eliminate CO2
ARF occurs rapidly (no time to compensate)
Acute resp failure types
NOT ON EXAM
(NOT ON EXAM)
Type1: hypoxemic
Type 2: hypercapnic
Failure to oxygenate
-2 issues that can cause it (examples)
Hypoventilation
-drug overdose (CNS depression)
-failure to exchange gas (decrease O2, increase CO2)
Intrapulmonary shunting:
-decreased perfusion to lungs
-pulmonary edema, pneumonia, atelectasis
Shunt issue in lungs
2 types
Blood leaves heart without exchanging gas
—Anatomic: heart defect bypasses lungs
—Intrapulmonary: pneumonia (fluid prevents gas exhange)
INADEQUATE OXYGENATION
Hypoxemia leads to what?
What is happening on a cellular level
Waste product we get
How that was product is buffered
Hypoxemia leads to hypoxia
Cells shift to anaerobic metabolism
—leads to lactic acid build up
—HCO3 required as a buffer
INADEQUATE OXYGENATION
4 other issues
Diffusion limitation
-gas exchange imapired (alveolar damaged)
(ARDS, pulmonary fibrosis)
Low CO:
Decreased CO = less oxygenated blood delivered
(Cells convert to anaerobic metabolism = lactic acid)
Low HGB:
(Sickle cell, carbon monoxide poisoning)
Tissue hypoxia:
(Aneaerobic metablism, lactic acidosis)
Failure of ventilation
4 issues
CNS problem: suppressed drive to breath
-OD, SCI, TBI
Neuromuscular condition
-guillain-barre syndrome (decrease drive to breath)
Chest wall problem
-flail chest/trauma
Problems w/ airway and alveoli
-COPD, CF
Assessment finding for ARF (6)
Early signs
Late signs
WOB
O2 sats
ABG
CXR
Early vs late signs in ARF
Early signs in older adults
Early:
-restlessness/agitation
-tachypneic
-tachycardia
Late:
-lethargic
-bradypneic
-bradycardia
-belly breathing
Early signs older adults:
-confusion, agitation, change in mental status
ARF interventions
-maintain patent airway how (3)
Optimize o2 (what we want)
Mobilize secretions
Decrease O2 demand
Airway:
-Bipap
-mechanical vent
-highflow NC
O2:
-goal PaO2 > 60, Sat >90
Secretions:
-positioning, coughing, chest PT, hydration
Other:
-decreased O2 demand
(Address fever, sz, restlessness)
Criteria for ARDS
(acute respiratory distress syndrome)
-Acute onset within 1 week of clinical insult
(Pneumonia, trauma to chest) something happened
-bilateral pulmonary opacities
-altered PaO2/FIO2 ratio
(Less than 300)
How to get an PaO2/FIO2 ratio
What is good
What is bad
What is severe ARDS
PaO2 divided by FIO2
Ex: 60 paO2 divded by 90% FIOS (0.90)
Good: over 300
Bad: under 300
Severe ARDS: under 100
Direct causes of ARDS
Pulmonary contusions
Trauma
Aspiration
Pneumonia
Emboli
Indirect causes of ARDS
Sepsis
Overdose
Transfusion acute lung injury
Anaphylaxis
Pancreatitis
S/s of ARDS (8)
Increased WOB
Hyperventilation (normal breath sounds)
Resp. Alkalosis then acidosis in late stage
Increase HR/fever
Chest xray =whiteout
Increased PIP ventilation
Severe hypoxemia
Deteriorating PaO2/FIO2 ratio
Neuromuscular blockades
2 names
Must infuse what with a paralytic?
Assessment you can do
3 things to do with vent patients
Cisatrcurium or vecuronium
Must infuse sedatives and pain meds w/ paralytics
Assess: train of four (tells us how paralyzed they are)
3 things to do:
-ROM
-SCDs
-lubricant for eyes
Treatment for ARDS
Treat cause (oxygenation and ventilation)
Treatment of ARDs
Normal PEEP
If PEEP is too high
-low tidal volume to decrease what?
-normal tidal volumes in healthy person?
Normal PEEP: 5
High PEEP: cause lung trauma
Low tidal volume to decrease volutrauma
Normal tidal volume: 500
Treatment of ARDS
Permissive hypercapnia? Except
Oxygen goal?
May have what BP issue with ARDS patient on vent and what to do?
Permissive hypercapnia:
- PaCO2 up to 60 is okay in early phases
except in TBI patients (bad for brain)
Goal: wean FIO2 to .60 or below but maintain adequate O2
May run hypotensive (lungs full we dont get that return)
-watch for HOTN and treat it
Treatment of ARDS
Positioning?
ECMO
Comfort meds
Decrease what?
Monitor what?
Prone up to 12 hours
may use ECMO
Comfort: sedation and analgesia
Decrease O2 consumption: paralytic/sedation
Monitor:
-fluid/electrolytes
-need adequate nutrition
-PaO2/FIO2 ratio
