Summary: Researchers at The Ohio State University have developed a ventilator-on-a-chip that compares the types of lung injury caused by mechanical ventilation. The study revealed that shear stress from the collapse and reopening of air sacs causes more damage and slower recovery than other mechanical stresses.

Key Takeaways:

  • The ventilator-on-a-chip enables real-time comparison of lung injuries caused by mechanical ventilation, showing that collapse and reopening of air sacs cause the most severe damage.
  • This model is a step forward in identifying therapeutic targets for ventilator-induced lung injury and will be used to model diseases like pneumonia and trauma in ICU patients.

For the first time, scientists have directly compared different types of injuries that mechanical ventilation causes to lung cells. Using a ventilator-on-a-chip model developed at The Ohio State University, researchers found that shear stress from the collapse and reopening of air sacs causes the most significant damage.

Innovative Ventilator-on-a-Chip Model

This “organ-on-a-chip” model simulates lung injury during mechanical ventilation, as well as repair and recovery, using human-derived cells in real time, according to co-lead author Samir Ghadiali, PhD, professor and chair of biomedical engineering at Ohio State.

“The initial damage is purely physical, but the processes after that are biological in nature – and what we’re doing with this device is coupling the two,” Ghadiali said. The team hopes the device will aid in developing therapies for ventilator-induced lung injury.

“This is an important advance in the field that will hopefully allow for a better understanding of how lung injury develops in mechanically ventilated patients and identification of therapeutic targets,” said co-lead author Joshua Englert, MD, associate professor of pulmonary, critical care, and sleep medicine at The Ohio State University Wexner Medical Center.

The research was published in the journal Lab on a Chip.

Comparison of Lung Injury Forces

Ventilators save lives in patients with severe respiratory problems, but mechanical forces exerted on the lungs can cause injury. These forces can lead to fluid buildup that interferes with oxygen transfer.

The ventilator-on-a-chip measures the effects of three types of mechanical stress: lung cell stretch from overinflation, increased pressure, and the cyclical collapse and reopening of air sacs. While both overinflation and collapse/reopening caused lung barrier leakage, recovery was slower from the latter.

The device uses an innovative approach: growing human lung cells on a synthetic nanofiber membrane that mimics the lung matrix. This provides real-time insights into the integrity of the lung barrier. Englert noted, “Our data suggests both forces are injurious, but collapse and reopening seems to be more severe and makes recovery harder.”

Next Steps in Lung Injury Research

Next, the researchers plan to use the ventilator-on-a-chip to model diseases such as pneumonia and traumatic injuries experienced by ICU patients.

“We’re in the early stages of developing some of those models,” Englert said. “This model is a platform we can build upon.”