Mechanical Ventilation for Thoracic CT in Canine and Feline Patients

Written and posted by Robert Whitaker - July 20, 2026

Thoracic CT has become a very useful diagnostic modality for evaluating pulmonary disease, metastatic cancer, mediastinal masses, and airway disorders in both canine and feline patients. While advances in CT technology have dramatically improved image resolution, one of the greatest determinants of image quality has to do with patient respiration.

Utilizing a mechanical ventilator during thoracic CT allows the imaging team to produce consistent, repeatable breath-holds that minimize respiratory motion artifacts. This results in better and more consistent image quality. The visualization of small pulmonary nodules and other fine details within the lungs should never be compromised because we skimped on the budget and didn't buy a good ventilator. It makes sense that each patient is scanned under the same controlled conditions to maximize consistency. Manual ventilation alone can never be as consistent as mechanical. 

Mechanical ventilation in feline patients should absolutely be required in veterinary practices with a CT. Cats are particularly susceptible to lung overinflation when manual breath-holds are performed. A ventilator allows the CT tech to deliver a preset tidal volume and inspiratory pressure. This gives the patient adequate lung inflation while reducing the risk of excessive distention. The patient is safer and the images are much nicer versus a manual breath-hold. 

Teaching manual apnea techniques to new technicians can be challenging. Achieving the proper inspiratory volume, coordinating the breath-hold with the CT acquisition, and maintaining consistency between patients all require experience. Mechanical ventilation simplifies this process by standardizing the technique, reducing variability between operators, and making it easier to train new staff members while maintaining a high standard of image quality.

As veterinary CT continues to evolve, attention should extend beyond the scanner itself. Optimizing patient ventilation is one of the most effective ways to maximize image quality, improve workflow, and increase diagnostic confidence. Investing in standardized ventilation protocols may prove just as valuable as investing in the latest CT technology.

At Veterinary Intelligence, we believe exceptional imaging begins with exceptional technique. Standardized ventilation protocols are another step toward helping practices achieve consistent, high-quality diagnostic studies. We cannot diagnose what we cannot see.

Source Materials

For those of you who are interested; here are three peer-reviewed publications that I drew upon to write this:

• Hordle T, Navarro-Carrillo I, Schofield I, et al. A Comparison of Two Different Methods for Inducing Apnoea During Thoracic Computed Tomography of Dogs. Animals. 2025;15(7):1014. This study demonstrates how controlled mechanical ventilation can provide reliable, repeatable apnea and improve image quality during canine thoracic CT examinations.

• Martins ARC, Ambrósio AM, Fantoni DT, et al. Computed Tomography Assessment of Tidal Lung Overinflation in Domestic Cats Undergoing Pressure-Controlled Mechanical Ventilation During General Anesthesia. Frontiers in Veterinary Science. 2022;9:842528. Using CT, this study identified ventilator pressure settings that minimize pulmonary overinflation in healthy cats, reinforcing the importance of controlled ventilation for obtaining diagnostic images while protecting delicate feline lungs.

• Bailey K, et al. The American College of Veterinary Anesthesia and Analgesia (ACVAA) Small Animal Anesthesia and Sedation Monitoring Guidelines 2025. Veterinary and Analgesia. These guidelines provide current recommendations for monitoring ventilation, oxygenation, and anesthetized canine and feline patients, supporting the safe use of mechanical ventilation during advanced imaging procedures.