Gas Exchange Flashcards
What is oxygenation ?
the mechanisms that facilitate or impair the body’s ability to supply oxygen to all cells of the body
What is ventilation ?
process of moving gases into and out of the lungs
What is perfusion ?
ability of the CV system to pump oxygenated blood to the tissues and return deoxygenated blood to the lungs
What is diffusion ?
exchange of respiratory gases in the alveoli and capillaries
What component of blood carries O2 and CO2 ?
hemoglobin
What body systems support oxygen transport ?
lungs and cardiovascular (CV) system
What side of the heart does oxygenated blood go to ?
Left side
What side of the heart does deoxygenated blood go to ?
Right side
What is cardiac output ?
amount of blood ejected from the left ventricle each minute
What is stroke volume ?
amount of blood ejected from the left ventricle with each contraction
What is preload ?
amount of blood in the LV at the end of diastole
What is afterload ?
resistance to left ventricular ejection
What components are part of cardiac output ?
Stroke volume (SV) x heart rate (HR)
How does stress affect oxygenation ?
a continuous state of stress or severe anxiety increases the metabolic rate and oxygen demand of the body
Why would anemia affect your oxygenation ?
if you don’t have enough RBCs then you won’t be able to carry enough O2
What is hyperventilation ?
ventilation in excess of that required
- rate and depth of respirations increases
What are some signs and symptoms of hyperventilation ?
- rapid respirations
- sighing breaths
- numbness and tingling of hands/feet
- lightheadedness
- loss of consciousness
What is hypoventilation ?
alveolar ventilation inadequate to meet the body’s oxygen demand
- respiratory rate and depth is low
What are some signs and symptoms of hypoventilation ?
- mental status changes
- dysrhythmias
- convulsions
- unconscious
- death
What are some causes of hypoventilation ?
- neuromuscular disorders
- atelectasis
- drugs (respiratory depression)
- trauma
What are some causes of hyperventilation ?
- severe anxiety
- infection
- COPD/Asthma
- DKA
- brain injury
What is hypoxia ?
inadequate tissue oxygenation at the cellular level, late sign cyanosis
What are some causes of hypoxia ?
- decreased in Hgb and lowered O2-carrying capacity of blood
- diminished inspired O2
- decreased in diffusion of O2 from the alveoli to the blood
- impaired ventilation
- poor tissue perfusion
What are some signs and symptoms of hypoxia ?
- decreased LOC
- increased RR and HR
- dizziness
- restlessness, inability to concentrate
- apprehensive
What are some late signs of hypoxia ?
- decreased RR and HR
- cyanosis
What is pneumonia ?
acute inflammation of the lung that is most frequently caused by a microorganism
- fluid and exudate in the alveoli
How does HOB up Semi-Fowlers help with respiration ?
helps to drain secretions from specific segments of the lungs and bronchi into the trachea
What are some additional interventions for respirations ?
- deep breathing and coughing
- pursed lip breathing
- flutter valve (clearing secretions)
- encourage fluids
- hydration
- humidification
- nebulization
What are some oxygenation safety info ?
- O2 must be prescribed and adjusted only with an order
- can prescribe O2 if pt is unstable but need to request order
- electrical equipment must be functioning and grounded
- no smoking/open flames
- secure O2 cylinders and store them upright and chained or secured in a holder
- check O2 level of portable tanks before transporting pt
What is the max amount of O2 per L/min does the nasal cannula use ?
6 L/min
- 24 to 44% O2
What % of O2 is in room air ?
21%
What % of O2 is 1L/min ?
24%
What is the rule for nasal cannula O2 concentrations ?
Starting at 1 L/min, increasing the oxygen flow by 1 L/min will increase the inspired oxygen concentration by about four percentage point
What is the max amount of O2 per L/min with a simple face mask ?
5-10L/min
- 35 to 60%
What is the max amount of O2 per L/min with a partial O2 mask ?
10-15L/min
- 60 to 90%
- reservoir bag must be inflated
What is the max amount of O2 per L/min with a non-rebreather O2 mask ?
10-15L/min
- 80 to 98%
- reservoir bag must be inflated
What is a venturi mask ?
delivers higher O2 concentration depending on the flow-control meter selected
- 4 to 15L/min
- 24 to 60%
What is the difference between BiPAP and CPAP ?
- BiPAP: gives 2 different pressure settings for inhale and exhale & set rate of breaths per min
- CPAP: stays at one single pressure setting and is to keep their airway open without being hooked up to O2
Why is suctioning important ?
with pt’s that are unable to clear respiratory secretions from the airways by coughing or other less invasive procedures
What is the max amount of time to suction ?
do not suction longer than 10-15 secs at a time
- allow 60 secs between passes
For continuous open suctioning up to what amount of mmHg is used ?
120 mmHg
For continuous closed suctioning up to what amount of mmHg is used ?
160 mmHg
How often is trach care for ?
minimum of every 24 hrs/daily
When doing trach care what do you change ?
- inner cannula
- site cleaning
- dressing change
(suctioning is not “daily trach care”)
For what situations would trach care and inner cannula changes be more often ?
new tracheostomies or pulmonary infections
What would you asses and document for trach care ?
q4hrs
- any trach care done
- type and size of trach
- stoma assessment
- all safety measures in place
- trach ties assessed (2 fingers underneath/skin assess)
When are Passy-Muir Speaking valves used and why ?
used with tracheostomy and ventilator patients
- helps them with speaking and communicating better
What is a chest tube ?
catheter placed through the thorax to remove air and fluids from the pleural space
What is the purpose of chest tubes ?
- remove air and fluids from the pleural space
- prevent air or fluid from reentering the pleural space
- re-establish normal intra-pleural and intra-pulmonary pressures
Where is a chest tube inserted ?
between the ribs into the chest (pleural space) and is connected to a closed water or dry seal
What is used to keep a chest tube in place ?
stitch (suture) and adhesive tape
What are some signs and symptoms of a hemo- or pneumothorax ?
- acute chest pain
- labored breathing
- dyspnea
- increased BP, HR, RR
- decreased O2 sat
- uneven chest wall movement
- deviation of airway
- very anxious
What are some chest tube interventions ?
- Maintain: secure and airtight dressing, & underwater seal, & tubing for patency & pt
- monitor and secure all connections
- observe for bubbling
- record output (quantity, characteristics)
- dressing changes per agency
Is bubbling in a chest tube canister normal ?
- bubbling in suction canister is normal
- continuous bubbling in the water seal is a sign of an air leak
What is the purpose of the incentive spirometer ?
to increase inspiratory volume, strengthen lungs and to help clear out secretions
For what L/min of O2 do we administer a humidifier ?
4L/min or greater
What is the purpose of a Venturi mask ?
for pt’s who need a very specific % of O2
- most accurate form of O2 delivery
What is the purpose of a face tent ?
fits loosely around the face and is often used for pt’s that feel claustrophobic
How are the simple face mask and non-breather face mask different ?
- simple face mask has holes at the end to allow for expiration
- non breather has valves that close during expiration
