Question 1

During a patient case study,increasing increments of PEEP showed no significant effects until 15 cm H₂O was used,at which time the PₐO₂ improved markedly.This represents the point at which _______________.

Accepted Answer

Recruitment maneuvers can produce varying results among patients.In patients who respond to an RM,P_aO₂ increases,P_aCO₂ decreases,and the change in pressure (ΔP)required to cause an acceptable Vᴛ decreases.

Question 2

The highest pressure attained during the slow-flow (quasi-static)technique should be ______ cm H₂O.

Accepted Answer

The slow flow for static P-V measurement uses a single breath delivered at 2 L/min until the pressure reaches 45 cm H₂O.

Question 3

"Loose atelectasis," or compression atelectasis,is most often associated with _____________.

Accepted Answer

Compression atelectasis,the result of gravitational pressure from lung and heart tissue,often occurs with anesthesia.

Question 4

The "sigmoid" shape of the static pressure-volume lung recruitment maneuver indicates which of the following?

Accepted Answer

The shape of the pressure-volume curve suggests that different areas of the lung open at different pressures during the recruitment maneuver.As pressure is exerted every few seconds,different areas of the lungs are recruited.This occurs between the lower inflection point on the inspiratory limb up to the upper inflection point on the inspiratory limb.

Question 5

An invasively ventilated patient with ARDS is on PC-CMV,PIP = 30 cm H₂O,PEEP = 12 cm H₂O,FɪO₂ = 1.0.The patient's returned Vᴛ is 320 mL.The ABG results on these settings are: pH 7.3,PₐCO₂ 53 mm Hg,PₐO₂ 62 mm Hg.The patient is placed in the prone position,and after 1 hour,ABG results show: pH 7.38,PₐCO₂ 46 mm Hg,PₐO₂ 83 mm Hg.The respiratory therapist should do which of the following?

Accepted Answer

This patient has shown a positive response to the prone position; therefore,the patient can be maintained in this position for 2-12 hours.A reduction in the FɪO₂ would be appropriate,because the level is at 1.0.

Question 6

The patient with which of the following assessment findings meets the criteria for beginning weaning from PEEP?

Accepted Answer

The criteria for initiation of weaning from PEEP include: (1)an acceptable PₐO₂ (90 mm Hg)on an FɪO₂ 0.4; (2)hemodynamic stability; (3)absence of sepsis; (4)improved CL (e.g.,CS > 25 mL/cm H₂O); and (5)PₐO₂/FɪO₂ ratio > 250 to 300.Choice "A" does not meet the minimum PₐO₂ or the minimum FɪO₂ and has a low Cₛ.Choice "B" has the appropriate PₐO₂,but the FɪO₂ is high and the Cₛ is low.Choice "C" has a high PₐO₂,but the FɪO₂ is 0.7,the calculated PₐO₂/FɪO₂ ratio is 214,and the compliance is just at the acceptable level.Choice "D" has all acceptable criteria,including a calculated PₐO₂/FɪO₂ ratio of 317.

Question 7

A recruitment maneuver (RM)is being performed on a patient receiving mechanical ventilation with PCV.During the maneuver the mode remains in PCV,rate = 10/min,I:E = 1:2,and PIP = 35 cm H₂O.The following information is documented during the RM:
$\begin{array} { | l | l | l | l | l | l | l | l | l | l | } 
\hline \text { Time } & 0800 & 0805 & 0810 & 0815 & 0820 & 0825 & 0830 & 0835 & 0840 \
\hline \text { PEEP } & 10 & 15 & 20 & 25 & 30 & 25 & 20 & 15 & 10 \
\hline \begin{array} { l } 
\text { Static } \
\text { Eampliance }
\end{array} & 24 & 29 & 34 & 25 & 22 & 27 & 31 & 36 & 32 \
\hline \text { EP } & 126 / 68 & 124 / 66 & 118 / 58 & 110 / 55 & 106 / 58 & 112 / 60 & 118 / 62 & 115 / 60 & 117 / 62 \
\hline \text { HR } & 108 & 108 & 105 & 100 & 100 & 102 & 105 & 106 & 105 \
\hline
\end{array}$
After the RM,the lungs are reinflated.At what level should the PEEP be set for this patient?

Accepted Answer

This is the PCV with increased PEEP recruitment technique.The point of decreased compliance on deflation represents the UIPd of the lungs.Once the lungs have been reinflated to allow reopening of lung units,PEEP is decreased until a pressure 2 cm H₂O above the UIPd is obtained.For this patient,that would be 12 cm H₂O.

Question 8

In which ventilator mode should a patient receiving a sustained inflation technique be placed?

Accepted Answer

To perform the sustained inflation technique,the ventilator needs to be set in the CPAP/spontaneous mode,because no mechanical breaths should be given during the procedure.The patient also requires sedation and short-term paralysis during this procedure.

Question 9

A patient with extensive infiltrates throughout the right lung should be placed in which of the following positions to improve oxygenation?

Accepted Answer

To improve oxygenation without uneven distribution of PEEP to the normal lung,the patient should be placed with the "good lung" down.

Question 10

Despite the risk,it is still important to use PEEP,because it can prevent alveolar collapse during exhalation and reopening,even when a low Vᴛ is used.It now is theorized that it is important to use the pressure-volume loop to set PEEP _____________________.

Accepted Answer

Regardless of the procedure used to establish an appropriate PEEP level,ventilating pressures should not be allowed to exceed the UIP on the UIPi,because injury to lungs can occur if the lungs become overstretched.The appearance of the UIP on the graphic display may be influenced by the type of recruitment procedure used.

Question 11

The point on a static pressure-volume curve (SPV)where the alveoli begin to open is referred to as which of the following?

Accepted Answer

At the lower inflection point on the inflation limb,the slope of the line changes significantly.It originally was believed that this point represents the opening of most of the collapsed alveoli.However,it is the point at which the alveoli begin to open.Even at the upper inflection point on the inflation limb,the alveoli are still being recruited in some parts of the lungs.

Question 12

To perform a slow-flow (quasi-static)technique for determining the appropriate PEEP level,the most appropriate ventilator flow setting is which of the following?

Accepted Answer

Although flow rates up to 9 L/min can be used,the higher flow rates cause a slight shift to the right of the resulting P-V curve.The single-breath slow flow should be 2 L/min.

Quiz 13: Improving Oxygenation and Management of ARDS