# Ventilatory Parameters

## Presentation on theme: "Ventilatory Parameters"— Presentation transcript:

Ventilatory Parameters
AKA weaning parameters

Parameters Respiratory Rate Tidal Volume Minute Ventilation
Vital Capacity NIF (MIP,MIF) RSBI

How to measure You need some type of volume measuring device
Wright Respirometer is a hand held device for this Measure exhaled tidal volume for one minute, it will accumulate and give you a minute ventilation

How to Measure cont. Take the minute ventilation value and divide by the RR. This gives you the average Vt Coach the patient to do a Vital Capacity Take the largest volume you obtain With another device, a manometer, measure the amount of negative force a patient can generate Do this by attaching the manometer and occluding all air and watch the manometer

How to Measure cont. You should have four values
Respiratory rate Minute ventilation Vital capacity Negative inspiratory force From these you can calculate Tidal volume RSBI

Respiratory Rate Normal 12-20 bpm Minimal values Less than 25 bpm
More than 10 bpm

Tidal Volume The average size tidal volume
Measure the Minute Ventilation and divide by the rate

Tidal Volume Normal about 5ml/kg Minimal values More than 250ml
Minute ventilation and RSBI are more important

Minute Ventilation Normal 5-10 lpm Minimal Values Less than 10
More than 5

Vital Capacity The maximum amount of air you can breathe out after inhaling as much as possible. “take a big breath in and blow it all out” FVC is the basic test done in a PFT The patient is not to use force for this test, we are measuring just the volume

Vital Capacity Normal Minimal values 10 ml/kg 1 liter (1000ml)

NIF Negative Inspiratory Force Maximum Inspiratory Pressure (MIP)
Maximum Inspiratory Force (MIF) The maximum amount of force a patient can generate while breathing in with a closed circuit.

NIF Normal values >100 cmH2O Minimal Values Greater than 20 cmH2O

RSBI Rapid Shallow Breathing Index
The more rapid and shallow the breathing the less effective it is Respiratory rate(f) divided by tidal volume(Vt) Single best indicator of post extubation success

RSBI Normal <105 Use the Vt and RR from the parameters gathered