midterm Flashcards
oxygen transport to tissues depends on
- cardiac output
- arterial oxygen concentration of hemoglobin
- metabolic requirements
room air has how much oxygen
21%
what is the goal of oxygen therapy
provide adequate transport of oxygen in the blood while decreasing the work of breathing and reducing stress on the myocardium
what is hypoxemia
decrease in arterial oxygen tension in the blood
manifestations of hypoxemia
- change in mental status
- dyspnea
- increased blood pressure
- change in heart rate
- dysrhythmia
- diaphoresis
- cool extremities
- central cyanosis (late sign)
what does hypoxemia lead to
hypoxia
what is hypoxia
a decrease in oxygen supply to the tissues
rapidly developing hypoxia may resemble what
alcohol intoxication
hypoxemic hypoxia
decreased oxygen levels in the blood resulting in decreased oxygen perfusion to the tissues
causes of hypoxemic hypoxia
- hypoventilation
- high altitude
- pulmonary embolism
- shunts (alveoli collapsed)
treatment for hypoxemic hypoxia
- increase alveolar ventilation
- oxygen
types of hypoxia
- hypoxemic
- circulatory
- anemic
- histotoxic
circulatory hypoxia
inadequate capillary circulation causes reduced tissue pressure (arterial oxygen remains normal)
causes of circulatory hypoxia
- decreased cardiac output
- local vascular obstruction
- low flow (shock, cardiac arrest)
treatment for circulatory hypoxia
identify and treat the cause
anemic hypoxia
decreased effective hemoglobin concentration causes decrease in oxygen carrying capacity of blood
(rarely accompanied by hypoxemia)
what causes a similar effect as anemic hypoxia
carbon monoxide poisoning
histotoxic hypoxia
a toxic substance that interferes with the ability of tissues to use available oxygen
ex. cyanide
oxygen toxicity
when too high an oxygen concentration (>50%) is administered for extended periods (>48 hours)
what causes oxygen toxicity
overproduction of oxygen free radicals
what can help defend against free radicals
vitamin E, C and beta-carotene
S&S of oxygen toxicity
- substernal discomfort
- dyspnea
- restlessness
- fatigue, malaise
flow rate of nasal cannula
1-6 L/min
>4 requires humidification
simple face mask flow rate
6-12 L/min
partial nonrebreather flow rate
10-15 L/min
how do patients with COPD stimulate respiration differently
they use a decrease in oxygen to stimulate respiration rather than increased CO2
do not give oxygen because it removes this stimulation and can cause a progressive increase in arterial CO2 pressure
what is an incentive spirometer used for
- helps a patient to deep breathe
- should be used 10 times an hour
what is an oropharyngeal airway for
allows airway patency in an unconscious patient
what is postural drainage
- allows gravity to assist in removal of bronchial secretions
- 2-4 times a day, before meals and at bedtime
- patient should remain in position for 10-15 minutes, breathe in slowly through nose and out slowly through pursed lips
- chest percussion and vibration help dislodge mucus (performed 3-5 minutes in each position)
how much urine should be collected for a culture
3mL
how much urine should be collected for routine analysis
20mL
how long should a catheter be clamped before collection
10-15 minutes
medical asepsis
“clean technique”
hand hygiene, gloves, cleaning the environment
in medical asepsis, something is considered contaminated if it
contains or is suspected to contain microorganisms
surgical asepsis
“sterile technique”
eliminates microorganisms and spores
in surgical asepsis, something is considered contaminated if it
touches something not sterile
3 situations surgical asepsis should be used for
- during procedure that perforates the skin
- if the skin integrity is broken (trauma, burns, incisions)
- during procedures that involve insertion of catheters or instruments into body cavities
4 things that contaminate something sterile
- out of vision
- below waist
- a wet contaminated surface (capillary action)
- 2.5 cm edges of a field
subQ: volume
0.5-1.5 mL
an IM injection should have how much muscle penetration
5mm
IM: needle length
1-2 inch
subQ: needle length
3/8-1/2 inch
usually 5/8
what type of insulin do you prepare first
short/rapid acting
subQ: guage
25-27
subQ: site
abdomen, back of arm, thigh
subQ pediatrics: volume
< 0.5mL
subQ pediatrics: guage
25-30
subQ pediatrics: needle length
< 1/2 inch
subQ pediatrics: site
either back of arm or thigh
subQ butterfly: volume
2-3 mL
subQ butterfly: guage
24g
clean needle stick protocol
- wash soap and water
- if necessary: first aid attendant
- review PPE and safe work practices
splash on intact skin/clothing protocol
- wash soap and water
- change clothes if necessary
- if necessary: first aid attendant
- review PPE and safe work practices
dirty needle stick
AND
splash on non-intact skin
protocol
- wash soap and water
- disinfect with alcohol swab
- apply sterile dressing if necessary
- DO NOT: squeeze, disinfect
blood/body fluid splash in eyes/nose/mouth protocol
- rinse membrane with tepid water/saline
- notify CNL
- ER within 2 hours
- source blood exposure work complete
- report exposure to occupational health nurse
hypotonic solution osmolarity
< 250 mOsm/L
isotonic solution osmolarity
250-375 mOsm/L
hypertonic solution osmolarity
> 375 mOsm/L
