Basic mechanical ventilation

Basic Mechanical Ventilation
Jairo I. Santanilla, MD Clinical Assistant Professor of Medicine Section of Emergency Medicine Section of Pulmonary/Critical Care Medicine LSUHSC New Orleans & Section of Critical Care Medicine Ochsner Medical Center

Outline
Outline
Basic Science
Lingo
Initial Settings
Common Intern Mistakes

How do we breath?
Brainstem control
Chemoreceptors
Diaphragm contraction and Chest wall expansion  increased intrathoracic volume
Leads to negative intrathoracic pressure
Air flows from high to low pressure
Negative pressure ventilation

Why do we breath?
Duh
Oxygenation
Ventilation – the exchange of CO2

Important Principles
Ventilation/Perfusion Matching
Ventilation without Perfusion
Dead space ventilation
Perfusion without ventilation
Shunt
Ideal Body Weight (kg)
Males: IBW = 50 kg + 2.3 kg for each inch over 5 feet.
Females: IBW = 45.5 kg + 2.3 kg for each inch over 5 feet.

Why do people need ventilators?
Loss of airway anatomy
Edema, direct/indirect trauma, burns, infection
Loss of protective airway mechanisms
Intoxicants, brain injury, strokes
Inability to oxygenate appropriately
Shunt, alveoli filled with stuff
Inability to ventilate appropriately
Expected clinical course

Basic Ventilator Lingo
Control breath
Vent initiates the breath
Assist breath
the patient initiates the breath

What can I set?
Ventilator Target
Ventilator Mode
Respiratory Rate
PEEP
FiO2
Flow Rate
Other stuff… more later

Step 1: What is the target?
You pick what the ventilator is trying to attain
If the vent is trying to reach a Volume goal, its called Volume-Targeted
AKA volume-cycled, volume-assist, volume- control, volume-limited.
If the vent is trying to reach a Pressure goal, its called Pressure-Targeted
AKA pressure-cycled, pressure-assist, pressure- control, pressure-limited
Most adult ICUs use Volume-Targeted and most PICUs use Pressure-Targeted