How to Read a Ventilator: A Beginner's Guide

Ventilators are one of the most intimidating pieces of equipment in the ICU — but once you understand the basics, they become much less scary. Here's a beginner-friendly breakdown:

What is a ventilator?

A ventilator is a machine that supports or replaces a patient's breathing. It delivers oxygen and removes carbon dioxide when a patient can't do it effectively on their own.

Key settings to know:

• Tidal Volume (TV) — the amount of air delivered with each breath
• Respiratory Rate (RR) — how many breaths per minute the vent delivers
• FiO2 — the percentage of oxygen being delivered
• PEEP — positive end-expiratory pressure that keeps the alveoli open

Common vent modes:

• AC (Assist Control) — delivers a set breath with every patient effort, plus backup breaths
• SIMV — allows spontaneous breathing between set breaths
• Pressure Support — supports the patient's own breathing efforts

What to watch for:

High peak pressures, patient-vent dyssynchrony, and sudden changes in oxygen saturation are all red flags that need immediate attention.