How to improve oxygenationwith Conventional Ventilator

Muhammad Asim RanaBSc, MBBS, MRCP, FCCP, EDIC, SF-CCM

Critical Care Medicine King Saud Medical City

Riyadh, KSA

Patient’s Data

• 37 yrs old alcoholic female with history of recurrent gall stones.

• Admitted with pancreatitis• Lipase 1120, Amylase 560.• 5th day developed SOB, worsened so electively

intubated.• FiO2 90%, Sat O2 78%, PaO2 48.

Chest Radiology

You only have Conventional Ventilator!

How can she be helped further to improve Oxygenation?

Modalities to Improve Oxygenation

• Increase Respiratory Rate• Increase PIP• Increase Volume• Increase PEEP• Increase Flow• Increase Inspiratory Time (I:E Ratio)

By Increasing MEAN AIRWAY PRESSURE

Can we say it more logically

Mean Airway PressureIncrease FlowIncrease peak pressureLengthen Inspiratory TimeIncrease RateIncrease PEEP

Pressure

T im e

Increasing Mean Airway Pressure1. Increase flow2. Increase peak pressure3. Lengthen inspiratory time4. Increase PEEP5. Increase Rate

Extra for the Experts

• The pt is on PCV with the following settings PEEP=12, FiO2=1.0, IP=18, PIP=28, Vt=350 ml (down from 450ml) & Slope is set at the slowest possible flow delivery.

• ABG’s on these settings are: • 7.28/49/53 (↓O2 ↑CO2 from previous). • The RT notices that PIP reaches only

23cmH2O. No leaks are found in the system. • What recommendations might be made to

improve this patient’s ABG’s?

Decrease the Rise Time

Better ventilation is actually accomplished by adjusting the slope to achieve a faster pressure delivery and increase the Vt,

The PIP will return to 28 cm H2O and the patient's ABG values will improve without further adjustments

Thank you