Chapter 12: Improve Ventilation

Question 1

How do you find desired Vt to get desired Paco2

Answer 1

Desired Vt = known Paco2 x known Vt / desired Paco2

Question 2

How do you adjust F to get desired PaCo2?

Answer 2

F desired = F known x Paco2 known / Paco2 desired

Question 3

What 3 factor affect Paco2 in mechanical ventilation ?

Answer 3

Total ventilation Ve

Dead space

CO2 production

Question 4

Two methods of increasing the Vt in pressure control ventilation are?

Answer 4

Increase set inspiratory pressure and increase inspiratory time

Question 5

What two formulas are used to predict the change in pressure necessary to achieve a desired PaCO2

Answer 5

Desired VT = actual VT X actual PAC02/desired PaCO2

Desired P = desired VT/Cs

Question 6

What is a normal VD/VT ratio?

Answer 6

0.2-0.4

Critical > 0.6

Question 7

Calculate a Vd/Vt ratio

Answer 7

Vd/Vt = (PaCo2-PetCo2)/PaC02

Question 8

List eight clinical disorders that may result in a hyper metabolic state

Answer 8

Fever, burns, multiple trauma, sepsis, hyperthyroidism, muscle tremors or seizures, agitation, and those patients who have undergone multiple surgical procedures

Question 9

List the suction pressure ranges for adults children and infants

Answer 9

Adults -100 to -120 mmHg,
children -80 to -100 mmHg,
infants -60 to -100 mmHg

Question 10

What is the estimated suction catheter size for a 7.0 ET

Answer 10

ET tube size x 3÷2

Question 11

What pressure should be used with a CASSET tube?

Answer 11

20 mmHg

Question 12

List the four types of aerosol generating devices that can be used to administer aerosolized medications during mechanical ventilation

Answer 12

Small volume nebulizer’s, pressurized metered dose inhaler’s,
ultrasonic nebulizers,
vibrating mesh nebulizers

Question 13

Which mode of mechanical ventilation is thought to be more effective for aerosol delivery

Answer 13

VCCMV

Question 14

What helps increase aerosol medication delivery

Answer 14

Although ventilator settings cannot always be adjusted for aerosol delivery, they can be helpful whenever possible to use low flow rates, high VT, and low respiratory rates during the treatment

Pressure meter does inhaler’s should use spacers roughly 7 inches from Y- connector

Larger ET 7mm or greater preferred

***Heated humidifiers can also affect aerosol delivery increase humidity increases particulate size is likely to reduce the amount of medication delivered to the patient. Place SVN proximal to heater

Question 15

List the sequence of four recommended positions that aid in secretion clearance for ventilated patients

Answer 15

Supine,
45° rotation prone with left side up,
45° rotation prone with right side up,
return to supine

Question 16

What type of patient problem should be suspected when the patient’s cardiac output in Reno output or decrease in the pulmonary artery occlusion pressure is increased?

Answer 16

These findings indicate left-sided heart failure

Question 17

What is considered normal urinary output

Answer 17

50 to 60 mL per an hour or approximately 1 mL per kilogram per an hour

Question 18

What affect does fluid balance have on blood cell counts

Answer 18

Fluid retention can cause dilution effect , called hemodilution, which leads to low hemoglobin, Low hemocrit, and low cell counts.

Do you hydration can cause hemoconcentration and falsely high readings of the same variables

Question 19

How to implement permissive hypercapnia

Answer 19

1) Hypercapnia should be implemented progressively in increments of 10 mmHg/H to a maximum of 80 mmHg/day. Paco2 allowed to rise >50-150< and PH can fall >7.1 to 7.3

Most believe ph 7.2-7.25 is acceptable. Increases in carbon dioxide have additional physiological effects are higher than normal PaCO2 stimulates the drive to breathe and therefore it is appropriate to provide sedation to patients with acute lung injury in a home permissive hypercapnia is being used the sedation may improve the patient comfort

2) If hypercapnia should exceed 80 mmHg, progress more slowly
3) FiO2 is adjusted to maintain arterial oxygen saturation (SaO2) of 85 to 90% this can require intermittent use of 100% O2
4) If permissive hypercapnia is used for less than 24 hours, PaCO2 can be allowed to decrease by 10 to20 mmHg/H, provided that PaCo2 is greater than 80 mmHg. The closer the patient is a norocapnia, the slower the process should be.
5) If permissive hypercapnia is used for more than 24 hours, or large amounts of buffer agents are use, discontinue even more slowly over 1 to 3 days

Question 20

Procedure for managing permissive hypercapnia

Answer 20

Allow PaCO2 to Rise Mph to fall without changing the mandatory rate or volume. Do nothing other than sedate the patient and avoid high ventilator pressures and maintain oxygenation.

Reduce CO2 production by using paralytic agents, cooling the patient, and restricting glucose intake

Administer agents such as sodium bicarb to keep pH greater than 7.25

Question 21

When is permissive hypercapnia contra indicated?

Answer 21

Carbon dioxide is a powerful vasodilator of the cerebral vessels does increase in CO2 levels can result in cerebral edema and increased ICP, which can aggravate cerebral disorders, such as cerebral trauma or hemorrhage, and cerebral occupying lesion’s. For this reason the use of permissive hypercapnia is contra indicated in the presence of disorders such as head trauma and intercranial disease