Skip to airway content Airway of the MonthRead the patient. Rescue the airway. Run the room.

Vent control

Recognize auto-PEEP

The best bedside clue is expiratory flow that has not returned to zero before the next breath starts.

Now check BP/MAPDynamic hyperinflation can cause shock.Increase expiratory timeGive the patient more time to exhale.

Flow, volume, and expiratory-hold clues

Flow, volume, and expiratory-hold clues

The pressure-time trace usually returns to set PEEP; intrinsic PEEP is quantified with a valid expiratory hold, not by eyeballing airway pressure alone.

Original Airway of the Month teaching diagrams redrawn from standard ventilator scalar and loop conventions. Interpretation is anchored to the AARC 2024 Patient–Ventilator Assessment guideline, the peer-reviewed Basics of Ventilator Waveforms review, the 2026 SYNAPsE asynchrony consensus, and the University of Pennsylvania Ventilator Overview and Troubleshooting tip sheet. Waveforms are pattern-recognition aids, not diagnoses; display colors, labels, and orientation vary by ventilator brand.

Look for

  • Expiratory flow remains below zero when the next inspiration begins.
  • Volume-time may not return to baseline.
  • Rising chest volume, increasing difficulty bagging, hypotension, or worsening hypercapnia may accompany severe dynamic hyperinflation.

Evidence and use limits

Last reviewed: 2026-07-17. Designed for: emergency medicine learners, clinicians, EMS, RT, and airway educators.

This is an educational cognitive aid, not a bedside order set. Confirm medications, ventilator changes, pediatric dosing, procedures, and escalation decisions against the patient’s physiology, the ventilator in use, and local ED/ICU/anesthesia/pharmacy/RT/EMS/pediatric policy.

Full references · Editorial policy · AARC 2024 ventilator assessment · ATS/ESICM/SCCM lung-protective ventilation · ATS 2024 ARDS update

About this resource
Created by: Andrew Pirotte, MD; Kyle Brown, MD; Reba Hodge, MD; Amanda Vanderwerf, PharmD, BCEMP; Morgan Kimball, PharmD, BCEMP; Joshua Mohess Clinical review: Emergency medicine faculty review completed. Medication content reviewed by Amanda Vanderwerf, PharmD, BCEMP, and Morgan Kimball, PharmD, BCEMP. Last reviewed: 2026-07-23 Next scheduled review: 2027-01-23 Designed for: EM residents, emergency physicians, EMS clinicians, airway educators, and simulation faculty Important: Educational resource and cognitive-aid guide only; not a bedside order set or substitute for local protocol, medical direction, or clinical judgment. Website contact: [email protected]