subgroup settings

Question 1

What are some specific patient subgroups

Answer 1

1. COPD
2. neuromuscular
3. asthma
4. closed head injury
5. acute respiratory distress syndrome (ARDS)
6. acute cardiogenic pulmonary edema (CHF)

Question 2

What is the R and C in COPD?

Answer 2

increase resistance and compliance

Question 3

What is the goals when ventilating COPD?

Answer 3

1. reduce WOB
2. increase pt-ventilator synchrony
3. long and complex wean

Question 4

which modes are suitable for COPD?

Answer 4

PC- CMV or DC-CMV

• descending flow waveform better match patient flow demand
• allow longer E time

VC-CMV

• need to match patient demand
• use decending ramp to avoid high pressure and maximizing distribution of ventilation

Question 5

What is the tidal volume range for COPD?

Answer 5

5 - 8 ml/kg

Question 6

What is a precaution for COPD patient?

Answer 6

monitor for Autopeep

Question 7

How to reduce chance of autopeep?

Answer 7

• lower VE
• permissive hypercapnea
• bronchdilators
• optimal E time

Question 8

What is the PaCo2 accept for these patient?

Answer 8

normal paCo2 : 50 - 60 mmhg

Question 9

What is the normal PaO2 for these patient?

Answer 9

55 - 75 mmhg

Question 10

Why not use PSV for COPD patient?

Answer 10

• patient is controlling the trigger and cycling meaning:
  1. I time can be too short or long
  2. can increase WOB and poor patient ventialtor synchrony

Question 11

What is the deal with neuromuscular disease?]

Answer 11

patient have normal:

• ventilatory drive
• normal or near to normal lung function
• require mechanical venilation because of respiratory msucle weakness

Question 12

What can respiratory muscle weakness lead to?

Answer 12

• limits patient ability to cough and clear secretion

- result: develop atelectasis and pneumonia , broncho-hyigene problem

Question 13

What is the ideal setting for NM?

Answer 13

Vt: 7 - 8ml/kg

mode: VC-CMV, with higher flowrate
weaning: straight forward

Question 14

What are the indication of ventilating Asthma patient?

Answer 14

1. exhaustion
   - ->RR decrease
   - ->decrease ph, increase Paco2
   - ->respiratory acidosis superimposed on metabolic acidosis
2. poor air entry
   - ->bilateral wheezes
   - ->air trapping increases
3. severe hypoxemia
   - ->refractory hypoxemia
4. depression of hemidiaphrams
   - ->air trapping
5. altered mental state
   - -> decrease LOC
6. dysrthymias
7. cardiac or resp arrest

Question 15

What are the ventialtor settings for asthma?

Answer 15

Fio2: as needed as long as it keeps Pao2 above 60

permissive hypercapnea: allow but watch ph because there maybe underlying metabolic acidosis

I:E: allow for longer E time

Vt: 4 - 8 ml/kg

Question 16

What is a closed head injury?

Answer 16

• brain injured but skull remains intact

- swelling of the brain leads to increase IP

Question 17

What is the formula of CPP?

Answer 17

CPP = MAP - ICP

Question 18

What happens to the CPP when there is a closed head injury?

Answer 18

due to increase in ICP, assuming no change in MAP, the CPP will decrease

Question 19

What does brain do when the CPP drops?

Answer 19

it decreases the CVR to increase the flow of blood

Question 20

what is the normal ICP?

Answer 20

less than 10 mmhg

Question 21

What is iatrogenic hyperventilation?

Answer 21

deliberate lowering of

PaCO2

Question 22

what is the effect of reducing PaCo2?

Answer 22

• result in cerebral vasconstriction, thus decreasingg ICP

Question 23

Whhat is the relationship between ph and CVR?

Answer 23

increase ph will increase CVR, decreasing the ICP

Question 24

What is another effect of increasing CVR

Answer 24

increase CVR decrease the blood flow reach to the brain–> decrease CPP

Question 25

What is the current recommendation for close head injury?

Answer 25

- PaCO2 < 35 mmHg is not recommended during first 24 hours because CBF is already lessened - It may be helpful for brief periods of time when ICP rises or until other measures can be instituted to decrease ICP - In normal ICP settings, hyperventilation should not be used - All attempts should be made to decrease Paw (low PEEP, moderate VT)

Question 26

What are the ventilator settings for close head injury?

Answer 26

Mode: - Full support is needed (VC, PC, DC CMV) VT: - 5-8 mL/kg and keep Pplat < 30mm MV: - to keep PaCO2 ~35mm, - target 30 - 35 mmhg if necessary Keep PaO2 70-100mmHg

Question 27

What is the primary strategy when treating ARDS?

Answer 27

1. Employ lung protective strategy | 2. keep pplate <30mmhg withh adequate oxygenation

Question 28

what are the settings for ARDS according to the guidlines?

Answer 28

VT: initially 8 ml/kg and titrate down from there, depending on Pplat --> If 4 mL/Kg still causes high Pplat then allow for permissive hypercapnia (pH as low as 7.20) RR: as high as possible without causing autopeep Flow: higher flow to reduce I time

Question 29

Why is Peep important for ARDS?

Answer 29

Prevents atelectrauma, improves shunt, improves compliance

Question 30

What is the optimal peep for ARDS?

Answer 30

be just above the inflection point on the deflation limb of a PV curve after the lung is maximally recruited

Question 31

What is the purpose of putting ARDS patient in a prone position?

Answer 31

improve V/Q, improve oxygenation

Question 32

how to position patient if they have unilateral lung disease (alveolar consoldiation)?

Answer 32

put the good lung down | -->gets better ventilation and gravity dependent lung always get better blood flow