Mechanical Ventilation Terminology
Name that Ventilator Alarm
Ventilator Graphics
Airway Pressure Monitoring
Formulas
100
The amount of air inhaled and exhaled in one cycle.
What is tidal volume?
100
Air leaks causing volume loss.
What is low inspiratory pressure?
100
Interpretation of these scalars reveal what?
What is Air Trapping?
100
Possible causes of a sudden increase in PIP.
What is Increased Airway resistance, decreased lung compliance or patient-ventilator interface problem?
100
Used to gauge respiratory muscle fatigue during a Spontaneous Breathing Trial by dividing frequency by tidal volume.
What is Rapid Shallow Breathing Index or (RSBI)
200
Amount of pressure delivered to patient during spontaneous ventilation.
What is Pressure Support?
200
Patient just received fentanyl and is on pressure support ventilation and has not triggered a breath within 20 seconds.
What is apnea alarm?
200
What is the cause of the change from pressure–volume loop A to pressure–volume loop B during volume-controlled continuous mandatory ventilation (VC-CMV)?
What is overdistention of the lung causing decreased compliance?
200
Static measurement done when flow has ended at the end of inspiration and reflects alveolar pressure during a period of no gas flow.
What is Plateau pressure?
200
Measures the effectiveness of oxygen transfer across the lung and is useful in determining the severity of ARDS.
What is the PaO2 to Fio2 (P/F) ratio?
300
Positive pressure applied by ventilator at the end of expiration
What is Positive end expiratory pressure (PEEP)?
300
Your patient has copious oral secretions and their O2 saturation has decreased.
What is high pressure alarm?
300
During a patient-ventilator system check the respiratory therapist sees the flow–volume loop below. What is the most appropriate action?
What is administer a bronchodilator? The expiratory flow part of the loop shows the scooped-out appearance. This is typical of a patient with airway obstruction.
300
Pressure that results from gas trapped in the lungs when inspiration begins before expiration is complete and can be measured by performing an expiratory hold maneuver.
What is Auto-PEEP?
300
The difference between the amount of oxygen in the alveoli and the amount of oxygen dissolved in the plasma and is an important measurement to help narrow the cause of hypoxemia.
What is the A-a oxygen gradient (PAO2-PaO2) or PAO2 = (Fio2 x (Patm-PH2O))-(PaCo2 /R)?
400
Highest pressure measured in the lungs upon inspiration.
What is Peak Inspiratory Pressure (PIP or Ppeak)?
400
The cuff of the ETT has a leak on full support, therefore the Vte has been between 150-250.
What is low exhaled tidal volume?
400
Looking at the waveforms what can you identify?
What is a volume leak causing active, prolonged exhalation?
400
The average pressure of inhalation and exhalation that acts on the lungs during mechanical ventilation that provides an overall assessment of the patient's ventilatory status and impacts oxygenation.
What is Mean Airway Pressure?
400
Formula used to assess the severity of hypoxic respiratory failure.
What is oxygen index (OI=Paw x Fio2 x100/PaO2)?
0 to 25 = Good outcome
25 to 40 = chance of death >40%
40 to >1000 = Mortality >80%, consider ECMO
500
The opposition to airflow in the lungs and is determined by the diameter of the airway.
What is airway resistance?
500
Your patient has increased SOB, chest pain, elevated heart rate, and abnormally rapid breathing. PIP and Pplat are increasing.
What is high pressure alarm?
500
This pressure-volume loop shows what abnormality?
What is air hunger or flow asynchrony (patient is not receiving enough flow)?
500
If both PIP and Pplat are increasing on the mechanical ventilator this is a sign that what is happening to the patient.
What is decreasing lung compliance?
500
2 formulas helpful in identifying if oxygen deliver is adequate.
What is Mixed venous oxygen tension (PvO2) and Mixed venous oxygen saturation (SvO2)?
If PvO2 is low: inadequate cardiac output, anemia or hypoxia. As O2 delivery decreases or O2 consumption increases, PvO2 and SvO2 will decrease. A PvO2 of <27 mmHg and SvO2 <50% are associated with lactic acidosis.
Remember Cardiac output, Hb and SaO2 greatly impact oxygen delivery to the tissues especially in critically ill patients.