Breath Biomarkers May Revolutionize Monitoring of Surgical Stress, New Study Finds

Unveiling the Invisible: Surgical Stress and Your Breath

Surgical procedures are demanding not just for surgeons, but especially for patients, whose bodies undergo significant traumatic stress during operations. Traditionally, doctors have relied on monitors tracking heart rate and blood pressure to assess stress responses. However, these conventional methods can be slow, invasive, and sometimes unreliable in capturing real-time physiological shifts. Now, a pioneering study published in BMC Anesthesiology suggests that the answer may be right under our noses—quite literally.

The Science Behind the Study

The research team led by Wang et al. set out to explore whether volatile organic compounds (VOCs) in exhaled breath could serve as non-invasive indicators of surgical stress. The researchers enrolled 105 adult patients undergoing abdominal surgery under general anesthesia. Breath and blood samples were collected at three critical stages: before incision (Pre-op), two hours into the operation (Intra-op), and immediately before extubation (End-op).

Utilizing cutting-edge ultraviolet photoionization time-of-flight mass spectrometry (UVP-TOF-MS), the team analyzed 296 different mass spectral features in patients’ exhaled breath, seeking correlations with traditional stress biomarkers such as norepinephrine, epinephrine, and cortisol.

Key Findings: Breath as a Window into Surgical Trauma

The results were striking. The abundance of certain VOCs in the breath changed dramatically during surgery, closely mirroring rises and falls in stress hormone levels. Notably, specific mass spectral features (e.g., m/z 42.9177, m/z 61.0104, and m/z 177.982) showed strong correlations with key biomarkers of traumatic stress.

Interestingly, the study found that the type of surgery—whether open or laparoscopic—didn’t significantly alter the breath profile when it came to detecting surgical stress. This suggests the method may be robust across various surgical techniques.

Why This Matters: Towards Personalized, Non-Invasive Patient Care

VOCs are already making waves in disease diagnostics, from cancer to infections. This study adds surgical stress to their potential, hinting at a future where anesthesiologists can monitor patient stress in real-time, non-invasively, and with greater accuracy. Such innovation could enable quicker interventions, better outcomes, and more personalized care.

Limitations and the Road Ahead

While promising, this was a preliminary study with a modest sample size and only three sampling time points. The authors acknowledge the need for further research, including real-time VOC identification and control for possible confounding factors like anesthetic drugs. Still, this work lays a crucial foundation for larger, more definitive studies.

Key Takeaways

Exhaled breath contains volatile compounds that change in response to surgical trauma.

These changes closely match traditional blood markers of stress, like cortisol and norepinephrine.

Breath analysis is non-invasive and may offer real-time monitoring advantages.

The method appears robust across different types of abdominal surgeries.

More research is needed before this approach can be widely adopted in clinical practice.

Citation:

Wang Q, Zhao Y, Li S, Li X, Wang H, Zuo Y. (2025). Association of exhaled breath volatile organic compounds with surgical traumatic stress. BMC Anesthesiology, 25:265. https://doi.org/10.1186/s12871-025-03140-9