Question Answer
3 types of scalar graphics Pressure-time, Flow-time, Volume-time
Time is always on which axis in scalars x-axis
2 types of Loops Pressure-volume, Flow-volume
Changes in Pressure-volume loop indicate what? changes in restriction(increase or decrease in compliance)
Changes in Flow-volume loops indicate what type of disease? obstructive
2 applications for Pressure-time scalar Determine breath type and use breath type to determine mode
In a pressure-time scalar, a dip in pressure during breath indicates what? insufficient flow
Which scalar waveform can identify obstructive disease? flow-time
Which scalar waveform can identify insufficient flow? pressure-time
Which loop waveform can identify obstructive disease? flow-volume
Which loop waveform can identify restrictive disease pressure-volume
In a pressure volume loop, volume doesnt begin until what is reached? inflection point
What is the inflection point? pressure needed to open alveoli
Why does compliance improve at infelction point? alveolar recruitment
How do you determine optimal PEEP? it is slightly above LIP
What is the upper inflection point? change in pressure without change in volume
Why does a “beak” occur in Pressure-volume loop? overdistention, overinflation of alveoli
When a “duckbill” or “beak” occurs on Pressure-volume loop, what do you do? reduce Vt, pressure until disappears
A pressure-volume loop shifted down and right indicates decreased compliance (increased PIP for volume)
A pressure-volume loop shift up and left indicates increased compliance(decreased PIP for volume)
When flow doesnt return to zero baseline on a flow volume loop, what is present? Air-trapping(Auto-PEEP)
In a pressure-time scalar, what does it indicate when PIP increases but Plat stays the same increased airway resistance(obstruction)
How do you resolve increased airway resistance as seen in a pressure-time curve bronchodilator, Sx, decrease I-time, Larger ETT
In a pressure-time scalar, what is indicated when PIP and Plat both increase? decreased airway compliace (restrictive)
How do you resolve decrease in compliance as seen on pressure-time scalar? decrease Vt, increase RR, permissive hypercapnia, PEEP therapy
A prolonged expiratory time seen on a flow-time scalar indicates what? airway resistance d/t obstruction
How to decrease airway resistance as seen on flow time curve? Tx, Sx, decrease I-time, larger ETT
If the pressure-time scalar waveform is scalloped it means flow is set too low, how cant you fix this? decrease I-time(increase flow), bronchodilator, Sx, decrease pressure sensitivity or chang to flowby
A large negative deflection on a pressure-time scalar indicates what excessive pt effort
How is an excessive pt effort shown on a pressure-volume loop? a deep fishtail on the negative portion of loop
Any loops showing volume will show the expiratory volume less than inspiratory volume (broken loop) which is d/t leak