Every 30 extra minutes under anesthesia raises complication risk in brachycephalic patients, underscoring the importance of perianesthetic management

Rebecca A. Johnson, DVM, PhD, DACVAA, said one of the key messages of her 2026 American Veterinary Medical Association (AVMA) Convention session on anesthetic and analgesic considerations for brachycephalic animals was that patient management is "just as important" as drug choice.¹

Johnson said brachycephalic animals have higher perianesthetic mortality than nonbrachycephalic dogs. She noted that the difference becomes smaller after accounting for American Society of Anesthesiologists (ASA) status, "but it doesn't go away." She put the figures at 1.6 times the mortality and 4.3 times the postanesthetic complications, among them regurgitation, aspiration pneumonia, dyspnea, dysphoria, and ventricular arrhythmias.

Every additional 30 minutes under general anesthesia raises complications by 18%, a point she returned to in urging short anesthetic times. Johnson also said no specific sedative or opioid has been identified as increasing complications, although she added that some protocols may still be preferable depending on the patient and procedure.

Risk scoring helps identify high-risk patients before anesthesia

Johnson encouraged attendees to score and record risk for every brachycephalic animal, pointing to brachycephalic risk (BRisk) scoring systems and conformation or the nostril grading system for pugs, French bulldogs, and other breeds. She noted that BRisk scores greater than 3 indicate a medium to high risk of complications, whereas scores greater than 4 indicate a high risk and warrant conversations with owners before anesthesia.

She paired those tools with the ASA classification, borrowed from human medicine, in which brachycephalic conformation alone moves a healthy elective patient from ASA 1 to ASA 2. "Even somebody coming off the street to spay their dog is an automatic ASA 2," she said, framing it as language clinics can use with owners. The score belongs in the record: "If you don't write it down, it doesn't happen," she added.

How brachycephalic anatomy complicates anesthesia

Beyond stenotic nares and everted saccules, Johnson emphasized the turbinates, which remain after surgery and help explain why procedures sometimes fail. A large tongue, floppy trachea, small epiglottis, and vocal fold granulomas compound the problem. Halving airway diameter increases resistance and work of breathing 16-fold, she said, and the resulting negative intrathoracic pressure worsens edema and can contribute to pulmonary edema, pushing PaCO₂ up and PaO₂ down. Johnson also emphasized that postoperative inflammation from the endotracheal tube itself can further narrow an already compromised airway, underscoring the importance of using appropriately sized tubes and minimizing trauma during intubation. High vagal tone, ventricular arrhythmias, chronic hypoxia, and gastrointestinal (GI) disease, including hiatal hernia and reflux, add further risk, with a history of GI disease raising the chance of aspiration.

Planning begins before the patient arrives

Because stress releases catecholamines that worsen many of these problems, Johnson recommended minimizing time in the waiting room, scheduling procedures first thing in the morning, signing consent ahead of the visit, and considering whether patients could wait in the owner's car rather than in the clinic (where appropriate and permitted by state regulations). Her behavioral modification, she said, is pharmacology: gabapentin the day before and morning of, plus "chill protocol" medications selected for the individual patient. She also discussed sending owners home ahead of time with preanesthetic medication kits that may include drugs such as gabapentin, trazodone, melatonin, maropitant, ondansetron, or cisapride, depending on the patient's needs, to help reduce stress and GI complications before the procedure.

She advised fasting for 4 to 6 hours with a small, digestible last meal, moving away from longer fasts, and stressed generous eye lubrication given the risk of proptosis and corneal ulceration. Johnson said preoxygenating patients for 3 minutes can extend the time before desaturation from about 1 minute to about 5 minutes, provided the mask remains in place.

Premedication and induction aim to reduce reliance on inhalants

When it comes to anticholinergics, Johnson said, "[They] are really controversial. I don't use them very often because…they take the watery part of the secretions away, but they leave the sticky part. Then it gets really sticky and hard to clear, so I don't use them very often."

Johnson also reviewed opioid options, ranging from butorphanol for short-duration, mild analgesia to fentanyl for short-duration, profound analgesia. She described using intravenous lidocaine or fentanyl to reduce coughing during intubation and a ketamine-propofol coinduction technique, emphasizing, "We are not going to mask these guys down."

She also cautioned against sedating brachycephalic patients and leaving them unattended, as muscle relaxation can quickly lead to airway obstruction. "Somebody needs to stand there because as they get muscle relaxed with their sedatives, they're going to obstruct," she said.

"Our goal is balanced anesthesia," Johnson added. She explained that using balanced anesthetic techniques and multimodal analgesia allows clinicians to use lower doses of individual drugs and reduce adverse effects.

Calling inhalants "the bad drugs," she described incorporating local anesthetic techniques, constant-rate infusions, and other adjunctive analgesic strategies to reduce inhalant anesthetic requirements.

Recovery is the most dangerous period

"Recovery is always going to be our most dangerous period," Johnson said, describing patients who obstruct, become hypoxic and hyperthermic, and aspirate. She walked through how to distinguish pain from dysphoria and emergence delirium, as each requires a different response. She recommended keeping patients sternal, extubating only once they can protect their airway, and closely monitoring them until they are fully awake, noting that many complications occur after extubation rather than during anesthesia.

Among the techniques Johnson discussed for managing postoperative airway obstruction were dexamethasone when appropriate, nebulized epinephrine, airway packing, and, as a last resort, tracheostomy, which is very invasive.

Johnson encouraged practices to develop hospital-specific protocols for brachycephalic patients, highlighting one example in which a hospital's protocol was associated with fewer postoperative respiratory distress events, although aspiration still occurred.

Johnson ended the session by returning to 3 key takeaways: (1) brachycephalic animals are at increased perianesthetic risk; (2) patient management is just as important as drug choice; and (3) most complications occur during recovery. "It's not so much about the drugs as it is the management," she said.

Reference

1. Johnson RA. From pugs to Persians…unique anesthetic and analgesic considerations and concerns for brachycephalic animals. Presented at: 2026 AVMA Convention; July 10-14, 2026; Anaheim, CA.