August 2026 |Ventilation During Anesthesia: The Quiet Driver Behind Recovery Quality
VITALS Newsletter — by Niki DeValk, AAS, LVT, SRS
Interventional & Surgical Specialist | Owner, NiKara Preclinical
Let’s Dive In
Hi everyone —
Running anesthesia in a research setting is never static. Every month brings new challenges, new insights, and new opportunities to sharpen our skills. This summer, I’ve spent a lot of time reviewing recovery trends across large‑animal studies, and one theme keeps rising to the surface: ventilation — not the dramatic kind, but the quiet, steady physiologic driver that shapes outcomes long before an animal wakes up.
This month’s issue digs into how CO₂ trends, alveolar recruitment, and oxygenation influence recovery quality, healing trajectories, and even study data. Ventilation deserves more attention, especially in facilities running long‑duration or high‑complexity procedures.
Let’s get into the August issue of VITALS — and explore the ventilation strategies that make recoveries smoother, safer, and more predictable.
Why This Topic Matters
Ventilation is one of the most overlooked variables in large‑animal anesthesia, yet it’s often the reason recoveries run long, animals emerge dysphoric, or post‑op physiology looks “off.” Even mild hypoventilation or V/Q mismatch can shift acid‑base balance, alter drug clearance, and change how an animal transitions out of anesthesia.
Ventilation issues often appear as:
ETCO₂ creeping above 55–60 mmHg
SpO₂ holding steady while PaO₂ quietly drops
shallow, inconsistent spontaneous breaths
delayed return of purposeful movement
These trends matter — and they predict recovery quality long before inhalants are discontinued.
Key Insights
ETCO₂ trends are more meaningful than single readings.
SpO₂ can look perfect even when PaO₂ is low.
Dorsal recumbency and long procedures increase dependent lung collapse.
Recruitment maneuvers prevent atelectasis before it starts.
PEEP improves oxygenation when used thoughtfully.
Positioning adjustments can dramatically improve ventilation.
What’s Changing
More teams are recognizing that ventilation must be actively managed throughout anesthesia. Common updates include:
adjusting tidal volume and rate based on CO₂ trends
performing recruitment maneuvers every 20–30 minutes
adding PEEP cautiously to support oxygenation
monitoring ETCO₂–PaCO₂ gradients when possible
repositioning animals to reduce dependent lung compression
These refinements reduce recovery delays, dysphoria, and prolonged apnea.
Clinical Connections
Ventilation challenges appear most often in:
long‑duration procedures
dorsal recumbency
deep inhalant planes
heavy body mass compressing dependent lung regions
Key strategies include:
Ventilation Targets
ETCO₂: 35–45 mmHg
PaO₂: >90 mmHg
pH: 7.35–7.45
Action Steps
increase rate or tidal volume when CO₂ rises
perform recruitment maneuvers every 20–30 minutes
add PEEP (start at 3–5 cmH₂O)
adjust positioning to reduce lung collapse
SpO₂ alone is not enough — PaO₂ can be low even when saturation looks perfect.
Case Study: The Yorkshire That Took Forever to Breathe on Its Own
The scenario: A 42‑kg Yorkshire pig undergoing a 2‑hour cardiovascular device procedure remained apneic long after inhalants were discontinued. ETCO₂ had been climbing for 45 minutes, spontaneous breaths were shallow, and recovery was slow and dysphoric.
The pivot: Ventilation had been set to a fixed rate without adjusting for rising CO₂. No recruitment maneuvers were performed, and the pig remained in deep dorsal recumbency with significant dependent lung compression.
Interventions included:
increasing tidal volume and rate to target ETCO₂ 35–45 mmHg
performing a recruitment maneuver
adding 5 cmH₂O PEEP
adjusting positioning
The outcome: Spontaneous breathing returned within minutes. Recovery stabilized, and purposeful movement returned quickly.
The takeaway: Ventilation is not a “set it and forget it” parameter. Rising CO₂ predicts recovery delays long before the animal wakes up.
Practical Takeaways
Watch trends, not snapshots — rising ETCO₂ is meaningful.
Recruit early — prevent atelectasis before it starts.
Position with intention — even small adjustments reduce lung collapse.
Use PEEP thoughtfully to support oxygenation.
Reassess ventilation frequently during long procedures.
Wrapping Up
Thank you for spending time with this month’s issue of VITALS. Ventilation may not be the flashiest part of anesthesia, but it’s one of the most powerful levers we have for smoother recoveries, stronger data, and safer procedures.
If your team is ready to strengthen ventilation skills, improve recovery consistency, or build study‑specific anesthesia confidence, I’m booking fall sessions now — virtual or hands‑on, individual or group.
Stay sharp. Stay supported. Stay vital.
— Niki
Niki DeValk, AAS, LVT, SRS
Independent Surgical & Anesthetic Specialist | Owner, NiKara Preclinical
📧 niki@nikarapreclinical.com 🌐 www.nikarapreclinical.com
