Ventilator Basics: Settings
Ventilators can look like spacecraft control panels, but once you understand the core settings, everything else falls into place. Today we're focusing on the "must-know" ventilator settings that will build your confidence and keep your patients safe.
The Fantastic Five Ventilator Settings
Mode: The Ventilator's Personality
Volume Control (AC/VC): "I promise to deliver exactly this much air, whatever pressure it takes!"
Pressure Control (PC): "I'll push with exactly this much pressure, whatever volume results!"
SIMV: "I'll give scheduled breaths, but I'll let you breathe on your own too."
PSV: "I'm just here to boost your own efforts. You lead, I'll support."
Tidal Volume (VT): The Air Package Delivery
Standard starting point: 6-8 mL/kg of ideal body weight
Too high? Hello, volutrauma and barotrauma!
Too low? Not enough gas exchange - not a great plan either
Pro tip: Shorter patients need smaller tidal volumes! Calculate, don't estimate.
Rate: The Breathing Rhythm
Adult starting range: 12-16 breaths/minute
Higher rates = more minute ventilation = more CO2 removal
Lower rates = less minute ventilation = CO2 retention
Remember: Rate × Tidal Volume = Minute Ventilation
PEEP: The Alveoli's Best Friend
Think of it as the minimum pressure maintained to keep alveoli from collapsing
Standard starting point: 5 cmH2O for most patients
Higher PEEP (10-24 cmH2O) often needed in ARDS to recruit collapsed alveoli
Too much PEEP can reduce cardiac output and cause barotrauma
FiO2: The Oxygen Dial
Start high (100% or 1.0), then wean down to target SpO2 of 92-96% (case dependent)
Goal: Keep FiO2 ≤ 60% when possible to avoid oxygen toxicity
Remember: High FiO2 feels safe but can cause absorption atelectasis and free radical damage
The Ventilator Alarm Cheat Sheet
High Pressure Alarm: Check for secretions, kinked tubing, patient biting tube, coughing, or bronchospasm
Low Pressure Alarm: Check for disconnections, cuff leaks, or circuit leaks
Low Volume Alarm: Similar to low pressure - look for leaks!
High Respiratory Rate: Patient distress? Pain? Anxiety? Acidosis? Time to investigate
Reality Check
Remember that the "perfect" ventilator settings don't exist - each patient is unique. Start with standard parameters, then assess and adjust based on ABGs, patient comfort, and clinical presentation.
Tomorrow: The most common pulmonary function test patterns and what they really mean!