Intro to O2 therapy Flashcards
Too much O2 will damage what? Physiological damage
- increased free radical leading to oxidative damage to vital organs
- mucosal inflammation
- cillia inactivation
- hemolysis
- desctruction of Type I pneumocytes
- increased production of Type II pnuemocytes
O2 Toxicity occurs at what levels?
375mmHg with FiO2~0.50 over 14hrs
O2 therapy precautions
- affects lungs at clinical PO2 levels- patchy infiltrates on x-ray in lower lung
CNS- hyperbaric pressures
pathophysiology; too much O2?
- damage capillary endothelium
- interstitial edema
- AC memberane thickiening
- changes in levels of type I and type II pneumocytes
- shunting–> hypoxemia
Increased metabolism by O2
- increased cellular byproducts than antioxidants can clean up
- recruit neutrophils (WBC)–> more inflammation and free radicals
Absorption Atelactasis
- nitrogen washout
- no non- diffusing gas remain in the lungs
- when O2 leaves, the alveoli will be vacant and collapsed
O2 hazards
- increased risk for fire
- cautious when using electronic equipment, scalpels, cardioconversion, cardio shock
Nasal Cath
FiO2: 0.24-0.44 with flow of 1-6LPM. 4% increases forver 1LPM inrease
- for babies
Nasal Canula
FiO2: 0.24-0.44 with flow of 1-6LPM. 4% increases forver 1LPM inrease
Simple mask
5-8LPM; FiO2 .40-.60
High flow NC
1-15LPM replaces PRBM
PRBM
6-15LPM (usually start at 10LPM); FiO2 0.60-0.80 and up
NRBM
8-15LPM; FiO2>0.80
Trans Tracheal Cathter
for difficult airways
placed through cricoid cartliage or between second and third tracheal ring
Oxymask
1-15LPM;FiO2 0.24-0.90
Low flow O2 devices
- Variable FiO2
- does not meet total inspiratory demands of patients
Percent O2 in atmosphere
21%
What is O2 used for
ATP production, angiogenesis, vasodilation/ vasoconstriction, suppress anaerobic bacteria
Hypoxia
inadequate O2 for cellular metabolism
hypoxemia
low blood O2 levels
causes of hypoxemia
decreased alveolar oxygen tension, increased altitude, inadequate ventilation (hypopnea, apnea)
Hypoxemia by shunt
perfusion no ventilation
hypoxemia via deapspace
ventilation without perfusion
response to hypoxemia
Increased MV, increased Cardiac output, Increased production of RBCs
signs and symptoms of hypoxemia
cyanosis, arrythmia, disorientation, polycythemia (high Hb - more chronic), lethargy
4 types of Hypoxia
hypoxic, anemic, ciruculatory, histotoxic
hypoxic hypoxia
not enough O2 in cells
responds to O2 therapy
circulatory hypoxia
normal blood O2 levels but not enough blood reaching the tissues
NO response to O2 therapy
histotoxiic hypoxia
Sufficient blood O2 levels and O2 delivered but inability of the tissues to use O2. e.g. CN poisoning
NO respose to O2 therapy
anemic hypoxia
not enough RBC to deliver O2 to tissues. Either due to RBC deformity, CO poisoning.
May respond to O2 therapy
