Respiratory and Hemodynamics
Card Set Information
Respiratory and Hemodynamics
What does hemodynamics tell us?
quantitative info about:
What does central venous pressure measure?
fluid volume status...and pressures in right atrium
looks at blood volume and venous return
What side filling pressure does central venous pressure measure?
What causes decreases in central venous pressure, pulmonary artery pressure and pulmonary capillary wedge pressure?
decreased venous return
Normal central venous pressure #s
What causes increase in central venous pressure?
Impedance to right atria emptying
What does the pulmonary artery pressure evaluate in the heart?
evaluates how the left ventricle is working
overall cardiac fxn
What does Pulmonary Capillary Wedge Pressure measure?
left ventricle function by measuring the amount of pressure generated by the left ventricle
Normal pulmonary capillary wedge pressure values?
What causes an increase in pulmonary capillary wedge pressure?
Impedence to LA emptying
the volume that fills the L ventricle at the end of diastole
wall tension generated by the LV during systole to open the aortic valve and eject it's contents
reflects the balance btwn oxygen supply and demand
Systemic Vascular Resistance
What does it measure?
What does systemic intra-arterial monitoring measure?
arterial blood pressure and correlates it to cuff BP
What increases preload?
What decreases preload?
What increases afterload?
What decreases afterload?
Calcium channel blocker-anti hypertensives
ROME in ABG's
Respiratory opposite (pH and CO2 going in opposite directions)
Metabolic equal (pH goes down so does HCO3...or both go up)
Define respiratory failure
inability of the cardiac and pulmonary systems to maintain an adequate exchange of oxygen and carbon dioxide in the lungs
What characterizes respiratory failure?
abnormal blood gas
What is oxygenation failure?
inadequate O2 transfer between the alveoli and the pulmonary capillary bed.
Common causes of oxygenation failure/hypoxemia?
mismatch of ventilation and perfusion
What is ventilatory failure?
mismatching in which the perfusion is normal, but ventilation is inadequate.
Thoracic pressure cant be changed enough to move air in and out of the lungs
What causes ventilatory failure?
abnormalities of the alveoli and airways
abnormalities of the chest wall
Crucial things to assess with impaired gas exchange
LOC/cap refill/skin color
Crucial things to assess with ineffective breathing pattern
RR and depth
changes in tidal volume and tidal capacity
Crucial interventions with inability to sustain spontaneous ventilation
monitor weaning from vent
decrease use of respiratory muscle depressant meds
provide periods of rest and activity
Interventions for ineffective airway clearance
monitor tidal volume and vital capacity
What makes a person be put on a vent?
severely inadequate gas exchange
progressive alveolar hypoventilation
What is the goal of mechanical ventilation?
to maintain alveolar ventilation appropriate for the client's metabolic needs
to correct hypoxemia
maximize oxygen transport
What characterizes a person is in ARDS?
acute onset of hypoxemia
bilateral chest imaging opacities
damaged alveolar capillary membrane causing it to become filled with fluid
Interventions for a person with ARDS
intubation and mechanical ventilation with PEEP
Medications given to a person with ARDS
sedatives and paralytics
Complications from ARDS
Why do people on a ventilator go in to renal failure?
the renal tissue doesnt get perfused due to hypotension, hypoxemia or hypercapnia
Also....they are given vanco a lot to prevent/treat infections
Indications for a person to be put on a vent
apnea...or impending apnea
acute respiratory failure
respiratory muscle fatigue
What are the goals of a person on a vent?
resolve hypoxemia and hypoxia
maximize oxygen carrying capacity of arterial blood
adequate cardiac output, Hgb
What is the purpose of a ventilator?
supports patients until they recover the ability to breathe independently
a bridge to long term mechanical ventilation...or until a decision is made to withdraw ventilatory support
How do you verify appropriate placement of an endotrachial tube?
End tidal CO2 detector...watch for a color change
Auscultate lungs for breath sounds
Auscultate epigastrum for the absence of air
Details about a Pressure Regulated Volume Control Ventilator
the ventilator monitors each breath and compares it to the tidal volume
If the delivered volume is too low, the pressure is increased on the next breath, and vice versa
Details about a Pressure Support Ventilator
used to assist with the weaning of a patient off a vent
patient must be able to initiate breath in this modality
Name and describe 2 non invasive mechanical ventilators
BIPAP-two different pressure levels, one for inspiration and one for expiration
CPAP-constant pressure is delivered
**Have to be able to breathe spontaneously on their own
How does an invasive ventilator work?
ET or trach is placed in the patient and air is pushed in to the patients lungs(inhalation) and exhalation is passive
What is PEEP?
positive pressure applied at the end of expiration to improve oxygenation by opening collapsed alveoli
What is the purpose of PEEP?
to maintain or improve oxygenation while limiting the risk of O2 toxicity
What does PEEP prevent?
small airway collapse at the end of expiration to increase oxygenation
List ongoing nursing care of a patient on a vent
assess position/placement of tube
doc tube placement in cm at teeth/lips
soft wrist restraints to prevent extubation
suction oral/tracheal secretions
assess respirotary status q1-2 hrs
reposition ET tube q24h
assess for skin breakdown
provide adequate nutrition
Monitoring of cuff pressure on a vent patient
must be below 20mmHg
assess for air leaks
How can you tell that there is a possible air leak in a ventilated patient?
What is a low pressure alarm signaling on a ventilated patient?
possible disconnection or leak in the system
loss of airway from total/partial extubation
ET tube/Trach cuff leak
What is a high pressure alarm signaling on a ventilated patient?
an increase pressure from sputum, fluid condensation, coughing, pneumothorax, bronchospasm, kink in tube
anything that will cause an increased resistance, obstruction
When do you suction? Rules of suctioning....
coughing, coarse rhonchi, high pressure, decreased spo2
hyperoxygenate....120max for 15 sec
assess for dysrhythmias....stop
monitor SaO2....<85% stop
dont put saline down ET Tube
How do you prevent VAP?
oral care with Peridex and tooth brushing
positioning to prevent aspiration...HOB at 30
prophylactic stress ulcer meds
dont change tubes regularly
S/S of VAP
CXR with pulmonary infiltrates
ABCDE bundle to facilitate weaning from mechanical ventilation is aimed at reducing....
development of delirium
all of which harm patients
Breathing trial..see if can spont. breath on own
Coordination....work with RT to get off vent
Delirium...are they delirious?
Early...can they get up and walk around the room while vented?
RN's collaborate with RT and Critical Care MD to wean a patient from vent....what criteria needs to be met to wean them....
awake and alert
negative inspiratory pressure >-20 H2O
Not on resp. depressant meds or anesthesia
Protective reflexes in tact
clear breath sounds
Most common way to wean a person from a ventilator
Indicators that vent weaning isnt going well...
SBP increase/decrease by 20
RR increase by 10 or above 30
HR increase/decrease by 20 or above 120
Most common sign that an older person is suffering from hypoxemia
change in mental status
Low SVO2 means....and caused by?
persons consuming more oxygen than the body has in reserves
High SVO2 means...
there's a maldistribution of blood related to SEPSIS