Oxygenation Flashcards
Alterations in respiratory function:
hypoventilation
hyperventilation
hypoxia
Hypoventilation:
Alveolar ventilation is inadequate to meet the oxygen demand of the body or eliminate sufficient carbon dioxide
Atelectasis is
a collapse of the alveoli, prevents normal exchange of oxygen and carbon dioxide
Hypoxia is
inadequate tissue oxygenation at the CELLULAR level.
Results from a deficiency in oxygen delivery or oxygen use at the cellular level
life threatening
Hypoxemia is
suboptimal normal partial pressure of oxygen.
Untreated hypoxemia will result in hypoxia.
Hypoxemia is common cause of hypoxia however hypoxia can exist without hypoxemia
Causes of Hypoxemia
Poor alveolar ventilation due to decreased tidal volume or respiratory rate
Decreased diffusion of oxygen from alveoli to pulmonary capillaries as a result of THICKENING of the alveolar-capillary membrane ventilation/perfusion mismatch
Shunting- occurs when venous blood travels from the right to left side of heart without passing by inflated alveoli resulting in MIXING of venous and arterial blood
Ventilation/perfusion mismatch
Causes of Hypoxia:
Anemic hypoxia
Ischemic stagnant hypoxia
Histotoxic hypoxia/dysoxia
Anemic hypoxia:
decreased ability to transport oxygen and can be result of low hemoglobin levels (anemia, hypovolemic shock) or reduced function of hemoglobin (carbon monoxide poisoning)
Ischemic/stagnant hypoxia:
occurs when there is decreased delivery of oxygen to tissue cells as a result of insufficient blood flow and which may be the result of systemic conditions (cardiac failure) or local disruption to circulation (tissue edema or local arterial damage).
Histotoxic hypoxia:
occurs when tissues are unable to properly utilize oxygen despite adequate oxygen supply and which occurs as a result of cellular poisons (cyanide), abnormal tissue oxygen requirements, or poor oxygen diffusion across cell membrane (tissue edema)
Hypoxemia ranges:
pO2 of less than 60 mmHG or an oxygen saturation of less than 90% leaving oxygen saturations in the range of 90-95%
Respiratory failure is defined as a
pO2 less than 50 mmHg and a pCO2 greater than 50 mmHG
Ventilation:
process of moving gases into and out of the lungs
Atelectasis:
collapse of the alveoli that prevents normal exchange of oxygen and carbon dioxide
External respiration:
exchange of O2 and CO2 between alveoli and blood
Gas transport:
blood transports O2 and CO2 to body cells
Internal respiration
exchange of O2 and CO2 between blood and cells
Blood and tissue oxygenation is through the process of ___________ (3)
Ventilation
Perfusion
Diffusion
Accumulation of carbonic acid in the body leads to
respiratory acid-base disorder termed respiratory acidosis
Majority of CARBON DIOXIDE molecules are transported in the blood as
BICARBONATE HCO2
Factors affecting respiration could stem from
integrity of the airway system (ventilation)
functioning cardiovascular system (perfusion)
functioning alveoli (diffusion)
functioning medulla & chemoreceptors
Physiologic factors Gas-exchange:
decrease oxygen-carrying capacity
hypovolemia
decrease inspired oxygen concentration
increased metabolic rate
Physiologic factors affecting gas-exchange:
Lung elasticity/compliance (ability to stretch and recoil)
Airway obstruction
musculature condition
trauma
neuromuscular disease
central nervous system
influences of chronic disease
Alteration in cardiac function that could affect oxygenation:
cardiac arrhythmias
congestive heart failure
valvular dysfunction
cardiac ischemia
Fick’s law of Diffusion
rate of a diffusion of gas is dependent on surface area and thickness of membrane
Factors affecting oxygenation
Developmental factors (age)
infants/toddlers
school age children and adolescents
young-middle age adults
older adults
medication
respiratory history
occupation
Psycho-social factors affecting oxygenation
environment
stress
emotions
health
Lifestyle factors: nutrition exercise smoking substance abuse
Afterload
resistance to left ventricular ejection
Angina pectoris
transient imbalance between myocardial oxygen supply and demand
results in aching, sharp, tingling or burning chest pain
Atelectasis
collapse of the alveoli that prevents normal exchange of oxygen and carbon dioxide
Bronchoscopy
procedure that allows viewing of airway through a thin viewing instrument called a bronchoscope.
During a bronchoscopy, your doctor will examine your throat, larynx , trachea , and lower airways.
Cardiac index
assessment of patient’s cardiac output based on size
Cardiac output
amount of blood ejected from the left ventricle each minute
normal: 4-6 L/min
increases during exercise, pregnancy, fever and decreases during sleep
Cardiopulmonary rehabilitation
helps patients achieve and maintain an optimal level of health through controlled physical exercise
nutrition counseling
relaxation and stress management techniques
prescribed medications and oxygen
cardiopulmonary resuscitation
CAB
Chest compression
Airway
Breathing
ventilation is done after first cycle of 30 chest compressions
Chest physiotherapy
group of therapies for mobilizing pulmonary secretions
include postural drainage, chest percussion and vibration
CPT is followed by productive coughing or suctioning of a patient who has decreased ability to cough
Chest tube
a catheter inserted through the thorax to remove air and fluids from the pleural space to prevent air or fluid from reentering the pleural space or to reestablish normal intrapleural and intrapulmonic pressures
common after chest surgery and chest trauma
used for treatment of pneumothorax or hemothorax to promote lung reexpansion
Cyanosis
bluish or purplish discolouration of the skin or mucous membranes due to the tissues near the skin surface having low oxygen saturation.
Diaphragmatic breathing
useful for patients with pulmonary disease, posted patients and women in labor to promote relaxation and provide pain control
improves efficiency of breathing by decreasing air trapping and reducing the WOB
Diffusion
movement of oxygen in the blood
dyspnea
associated with hypoxia
subjective sensation of difficult or uncomfortable breathing
shortness of breath usually associated with exercise or excitement, pulmonary diseases, cardiovascular diseases, neuromuscular conditions and anemia
exaggerated respiratory effort
Dysrhythmias
electrical impulses that do not originate from the SA node cause conduction disturbances
rhythm disturbances, deviation from the normal sinus rhythm
occur as a primary conduction disturbance such as in response to ischemia, valvular abnormality, anxiety, drug toxicity, caffeine, alcohol/tobacco, complication of acid base or electrolyte imbalance
Electrocardiogram (ECG)
electrical activity of the conduction system
monitors the regularity and path of the electrical impulse through the conduction system
does not reflect muscular work of heart
Normal sequence on ECG is called
normal sinus rhythm
Expiration
PASSIVE process that depends on the elastic recoil properties of the lungs, requiring little or no muscle work
Inspiration
active process stimulated by chemical receptors in aorta
Hematemesis
vomiting of blood
Hemoptysis
coughing up blood
Hemothroax
accumulation of blood and fluid in the pleural cavity between the parietal and visceral pleura and usually result of trauma
Humidification
process of adding water to gas
Hyperventilation
lungs remove carbon dioxide faster than it is produced by cellular respiration
anxiety, infection, drugs or acid base imbalance induce hyperventilation
RAPID RESPIRATIONS, SIGHING BREATHS, NUBNESS AND TINGLING OF HANDS/FEET, LIGHT HEADEDNESS, LOSS OF CONSCIOUSNESS
Hypoventilation
alveolar ventilation is inadequate to meet the oxygen demand of the body or eliminate sufficient carbon dioxide
body retains CO2
- can lead to respiratory acidosis/arrest
mental status change, dysrhythmias, potential cardiac arrest
Nasal cannula
simple comfortable device used for precise oxygen delivery
Simple masks
short term oxygen therapy …
useful for short periods such as patient transportation
Partial rebreather
a breathing set that recycles exhaled air and mixes that with a breathing gas containing oxygen. This reduces the amount of breathing gas needed.
Non-rebreather
requires that the patient can breathe unassisted, but unlike low flow nasal cannula, the NRB allows for the delivery of higher concentrations of oxygen.
CPAP
Continuous positive airway pressure
treats patients with obstructive sleep apnea, heart failure and preterm infants with underdeveloped lungs
BIPAP
Bilevel positive airway pressure
provides both inspiratory positive airway pressure (IPAP) and expiratory airway pressure (EPAP)
difference between two pressures indicates amount of pressure support patient needs
Ventilator (ET)
Endotracheal tube
short term artificial airway to administer invasive mechanical ventilation, relieve upper airway obstruction, protect against aspiration or clear secretions
Ventilator (Tracheostomy)
long term assistance
surgical invasion made into trachea
patients can’t speak because tube is inserted below vocal cords
Normal respiratory rate of newborn
30-60 breaths/min
PQRST
Provokes
quality
region/radiation
severity scale
timing
Tachypnea
R>24
Bradypnea
R<10
Hypovolemia
Extracellular fluid loss and reduced circulating blood volume
4 factors that influence adequacy of circulation, ventilation, perfusion and transport of respiratory gases to tissues
physiological
developmental
lifestyle
environmental
Orthopnea
abnormal condition in which a patient uses multiple pillows when reclining to breathe easier or sits leaning forward with arms elevated
Apnea
absence of respirations lasting for 15 seconds or longer
Cheyne-stokes respiration
occurs when there is decreased blood flow or injury to the brainstem
Oxygenated blood leaves the heart and is pushed to the tissues via
aorta
The ______ returns deoxygenated blood from the body to the heart
inferior vena cava
Deoxygenated blood moves from the right atrium to the lungs via __
pulmonary artery
Oxygenated blood from the lungs flows into the ____
left atrium
Deoxygenated blood from the body flows through the ____ system to the heart, flowing into the _________
venous system
right atrium
Oxygenated blood is pumped to all parts of the body from the _______
left ventricle
Deoxygenated blood from the heart is pumped from the ______ to the _______ for oxygenation
right ventricle
lungs
Upper respiratory tract includes
nose
nasal cavity
sinuses
pharynx
Lower respiratory tract contains
larynx, where the vocal cords are
trachea
bronchi, bronchioles, alveoli
Which nerve do impulses travel through to stimulate diaphragm to move downward during inspiration
phrenic nerve
Intercostal nerve stimulates the
intercostal muscles along the ribs to contract
During ____, the diaphragm relaxes, the chest and lung tissues ____ and intraalveolar pressure ___ causing air to be forced out of lungs
expiration
recoil
increases
During expiration, pressure is
decreased volume in thoracic cavity
increases pressure in lungs causing air to flow out
Inspiration volume and air pressure
increased volume in thoracic cavity
decreased air pressure- draws air into lungs
External respiration:
exchange of gases between the lungs and blood
Internal respiration
exchange of gases between the blood and tissues
cellular respiration
cells use the oxygen for metabolism, releasing carbon dioxide
Which part of respiratory tract does air pass after moving through trachea?
Bronchioles
alveoli
Perfusion is
when oxygen enriched blood then travels to the body’s tissues
Damage to the epicardium would cause
impaired secretion of serous fluid
increased friction during heart contractions
Steps of inspiration and expiration
Respiratory center in brain releases an impulse to nerves
phrenic nerve stimulates the diaphragm to move downward and the intercostal nerve causes the intercostal muscles to contract
the chest cavity expands, causing decreased idntraalveolar pressure
atmospheric pressure exceeds idntraalveolar pressure, causing air to move into the respiratory tract and the lungs fill with air
diaphragm relaxes and idntraalveolar pressure increases
air is forced out from the lungs
Coronary arteries include the
right coronary
left main
left anterior descending
circumflex
Common disorder that impairs airflow in lungs due to inflammation and structural damage
chronic obstructive pulmonary disease which includes emphysema and chronic bronchitis
Chronic bronchitis characteristics
inflammation of the large airways
increased mucus production
chronic cough
Fick’s law of diffusion:
rate of diffusion of gas is dependent on SURFACE AREA and THICKNESS of the membrane
