What is the optimal PEEP level given the following information? ...

[leilurhhh]

What is the optimal PEEP level given the following information?
 
  Time 0600 0615 0625 0635 0640 0650
  PEEP 0 5 8 10 12 15
  PaO2 (FIO2 = 0.6) 50 62 75 81 86 103
  Cs (mL/cm H2O) 16 21 28 38 34 30
  BP 140/90 130/90 120/90 120/90 118/80 100/70
 
  a. 8 cm H2O
  b. 10 cm H2O
  c. 12 cm H2O
  d. 15 cm H2O

Question 2

Which of the following is the most appropriate PEEP level for the patient whose information is in the table below?
 
  Time 0140 1050 0155 0200 0205 0210
  PEEP (cm H2O) 5 8 10 12 15 18
  CO (L/min) 3.5 3.5 3.6 3.6 3.2 3.2
  Mixed ve-nous PO2 (mm Hg) 28 39 43 45 42 27
  BP 140/90 133/90 124/90 120/80 115/78 100/70
 
  a. 10 cm H2O
  b. 12 cm H2O
  c. 15 cm H2O
  d. 18 cm H2O

[jamesnevil303]

Answer to Question 1

ANS: B
At a PEEP of 10 cm H2O, the Cs is at its highest level, and the PaO2 and BP are at acceptable levels. At 12 cm H2O, the Cs is reduced, and it declines further at a PEEP of 15 cm H2O.

Answer to Question 2

ANS: B
At a PEEP of 12 cm H2O, the cardiac output is at its highest level (3.6 L/min), and the mixed venous PO2 is at its highest level. This correlates with an enhancement in cardiac performance. However, at a PEEP of 15 cm H2O, both these indices, as well as the blood pressure, are re-duced, meaning that the alveoli are overdistended and the point of optimum PEEP is no longer present.