The Phone Call Nobody Wants
Last October, I got a call from a woman named Patricia in upstate New York. Her eight-year-old Rough Collie, Jasper, had been diagnosed with a splenic mass. The vet recommended surgery - soon. Patricia knew Jasper was MDR1 mutant/mutant. She’d tested him as a puppy, kept the results in his file, reminded her vet at every appointment. She’d done everything right.
But now she was facing something she hadn’t prepared for: a major surgery. A full anesthetic event. Hours on a table while drugs flowed through her dog’s veins - drugs that his compromised blood-brain barrier might not handle the way a genetically normal dog would.
“I know which pills to avoid,” she told me, her voice cracking. “But I don’t know the first thing about anesthesia. I don’t know what questions to ask. I don’t even know if surgery is safe for him.”
Patricia isn’t alone. I hear some version of this conversation at least twice a month. Owners who’ve mastered the medication danger list, who carry vet visit checklists in their wallets, who can recite the MDR1 mutation’s mechanism from memory - but who freeze when surgery enters the picture.
This guide is for Patricia, and for everyone who will eventually face the same situation. Because every dog, at some point in their life, will likely need anesthesia. Dental cleanings, mass removals, spay and neuter procedures, emergency interventions. The question isn’t if - it’s when.
Yes, MDR1 Dogs Can Have Surgery Safely
Let me say this clearly before we go any further: having the MDR1 mutation does not mean your dog cannot have surgery. It does not mean anesthesia is off the table. It does not mean you should refuse a procedure your dog genuinely needs out of fear.
What it means is that the anesthesia protocol matters more for your dog than it does for a genetically normal dog. It means your veterinary team needs to know your dog’s status, plan accordingly, and monitor more carefully. It means you need to be informed and involved in the conversation before your dog ever enters the operating room.
Dogs with the MDR1 mutation undergo successful surgeries every day. Dental cleanings, tumor removals, orthopedic repairs, emergency procedures. The outcomes are overwhelmingly positive when the team is prepared. The tragedies happen when they’re not.
Start the Conversation Early
The worst time to discuss anesthesia protocols with your vet is the morning of surgery. The best time is weeks before, when everyone is calm and there’s room for research, consultation, and planning.
The moment surgery is recommended - or even discussed as a future possibility - schedule a separate appointment specifically to talk about the anesthetic plan. This isn’t part of the pre-surgical bloodwork visit. This isn’t a five-minute sidebar during a checkup. This is a dedicated conversation, and it deserves dedicated time.
Bring your dog’s MDR1 test results. Bring a printed copy even if they’re in the file. Bring the vet visit checklist we’ve developed for exactly these situations. And bring questions. Lots of questions.
The Questions You Need to Ask
I’ve compiled these from conversations with veterinary anesthesiologists, pharmacologists, and dozens of MDR1 dog owners who’ve been through surgical procedures. Not every question will apply to every situation, but having the full list means you won’t forget the critical ones.
About the Anesthesia Protocol
“What pre-anesthetic sedation will you use?”
This is the first drug your dog receives, usually given as an injection before the main anesthesia. Acepromazine is one of the most commonly used pre-anesthetic sedatives in veterinary medicine, and it’s on the MDR1 danger list. In affected dogs, it causes prolonged and exaggerated sedation that can complicate the entire procedure.
Safer alternatives include dexmedetomidine (which has the critical advantage of being reversible with atipamezole) and midazolam. Ask specifically what will be used and whether it interacts with the P-glycoprotein pathway.
“What induction agent will you use?”
Induction is the transition from sedation to full anesthesia. Propofol is widely considered safe for MDR1 dogs and is the most common induction agent in modern veterinary practice. Alfaxalone is another option with a good safety profile. Ask your vet to confirm which they’ll use.
“What maintenance anesthesia will you use?”
Once your dog is under, they’ll be kept anesthetized with an inhalant gas. Isoflurane and sevoflurane are both generally well-tolerated by MDR1-affected dogs. These gases are eliminated through the lungs rather than being processed through the liver and P-glycoprotein pathway, which makes them inherently safer for MDR1 patients.
“What pain management will you use during and after surgery?”
This is where things get nuanced. Butorphanol, a commonly used veterinary opioid, is a P-glycoprotein substrate and can cause exaggerated effects in MDR1 dogs. Ask about alternatives. Non-steroidal anti-inflammatory drugs like carprofen or meloxicam are generally safe. For more extensive pain control, our guide to safer drug alternatives covers the full landscape of options.
“Do you have reversal agents on hand?”
One of the advantages of certain modern anesthetic drugs is that they can be reversed. Dexmedetomidine can be reversed with atipamezole. Some opioids can be reversed with naloxone. Having reversal agents immediately available means that if your dog shows an exaggerated response, the team can act quickly rather than simply waiting for the drug to wear off - a process that takes much longer in MDR1 dogs.
About Monitoring
“Will someone be dedicated to monitoring anesthesia throughout the procedure?”
In larger practices and specialty hospitals, a veterinary technician is assigned exclusively to monitor the patient’s vital signs during surgery while the surgeon operates. In smaller practices, the surgeon might also be monitoring. Neither is inherently wrong, but knowing the setup helps you understand the level of oversight your dog will receive.
“What monitoring equipment will be used?”
At minimum, you want pulse oximetry (blood oxygen levels), capnography (CO2 levels), ECG (heart rhythm), and blood pressure monitoring. These are standard in modern veterinary surgery. If a practice doesn’t use all of these, consider whether a better-equipped facility is available.
“Will you adjust drug doses based on MDR1 status?”
Many anesthesiologists recommend starting with lower doses for MDR1-affected dogs and titrating up as needed, rather than giving a standard dose and hoping for the best. This “start low, go slow” approach is particularly important for pre-anesthetic sedatives and any opioid pain medications.
About Recovery
“How long do you expect recovery to take?”
MDR1-affected dogs often take longer to recover from anesthesia than genetically normal dogs. This isn’t necessarily a sign that something went wrong - it’s a known characteristic of how their bodies process these drugs. Understanding this in advance prevents panic during the recovery period.
“Will my dog be monitored continuously during recovery?”
The recovery period is arguably the most critical phase for MDR1 dogs. As anesthetic drugs redistribute and are metabolized, an MDR1-affected dog’s compromised P-glycoprotein pump means these drugs may linger longer in the brain. Continuous monitoring until your dog is fully alert and responsive is essential.
“When can I take my dog home, and what should I watch for?”
Get specific discharge criteria. Don’t accept “when he seems ready.” Ask for measurable benchmarks: walking unassisted, responsive to voice, eating and drinking, stable vital signs for a defined period. And ask what signs should prompt an immediate return to the hospital.
The Pre-Surgical Preparation Timeline
Here’s what a well-prepared surgical experience looks like for an MDR1-affected dog, working backward from the procedure date.
Two to Four Weeks Before Surgery
- Schedule a dedicated anesthesia discussion with your vet or the surgeon
- Confirm your dog’s MDR1 test results are in the surgical facility’s file - not just your regular vet’s file, if they’re different
- Request the complete anesthesia protocol in writing
- Research the proposed drugs using resources like MDR1 Gene Guide, which maintains detailed information on how specific drugs interact with the MDR1 mutation
- If your regular vet isn’t performing the surgery, ensure the surgical team has your dog’s complete medical history
One Week Before Surgery
- Complete pre-surgical bloodwork (CBC, chemistry panel, coagulation profile)
- Confirm the surgical date, arrival time, and fasting instructions
- Prepare a one-page summary of your dog’s MDR1 status, including the test result, known drug sensitivities, and emergency contact information
- Make two copies: one for the surgical file, one to physically hand to the attending veterinarian on the day of surgery
The Night Before
- Follow fasting instructions precisely (typically no food after midnight, water usually permitted until morning)
- Prepare a carrier or comfortable space in your car for transport home
- Charge your phone - you’ll want it available for calls from the surgical team
- Write down the hospital’s phone number, the surgeon’s name, and the closest emergency veterinary hospital in case complications arise after hours
Day of Surgery
- Arrive early enough to speak directly with the veterinarian or anesthesiologist who will be managing your dog’s case
- Hand them the written summary of your dog’s MDR1 status, even if it’s already in the file
- Verbally confirm: “My dog is MDR1 [mutant/mutant or normal/mutant]. Please confirm the anesthesia protocol accounts for this.”
- Ask what time you should expect an update call, and who will call you
- Leave your phone on. Answer immediately.
When to Consider a Specialist
There are situations where a general practice veterinarian is perfectly capable of safely anesthetizing an MDR1-affected dog. Routine dentals, simple mass removals, spay and neuter procedures - these are well within the wheelhouse of most competent general practitioners who are informed about your dog’s status.
But there are also situations where a veterinary anesthesiologist or a specialty hospital is the better choice:
- Complex or lengthy surgeries where your dog will be under anesthesia for more than an hour
- Emergency procedures where there’s less time to plan and the stakes are higher
- If your regular vet is unfamiliar with MDR1 and seems uncertain about protocol modifications
- If your dog has other health conditions that complicate anesthesia (heart disease, kidney disease, advanced age)
- If previous anesthetic events have been problematic - prolonged recovery, unexpected reactions, or difficulty maintaining stable vital signs
Veterinary teaching hospitals affiliated with universities often have the most experience with MDR1-specific anesthesia protocols. If you’re near a veterinary school, it’s worth exploring whether they accept referral cases for surgery.
Patricia’s Story: How It Ended
I want to circle back to Patricia and Jasper, because their story illustrates what preparation looks like in practice.
After our phone call, Patricia scheduled a consultation with a veterinary surgeon at Cornell University’s animal hospital, about two hours from her home. She brought Jasper’s MDR1 test results, his complete medical history, and a printed list of questions based on an earlier version of this guide.
The surgical team at Cornell was familiar with MDR1. They’d operated on herding breeds before. They developed a customized anesthesia protocol: dexmedetomidine for pre-anesthetic sedation (with atipamezole standing by as a reversal agent), propofol for induction, isoflurane for maintenance, and carprofen for post-operative pain management. No acepromazine. No butorphanol.
Jasper’s surgery lasted ninety minutes. The splenic mass was removed successfully. It turned out to be benign - a hemangioma, not the hemangiosarcoma Patricia had feared.
Recovery took longer than average. Jasper was groggy for about six hours post-surgery, compared to the two-to-three hours typical for a normal dog. The team at Cornell expected this and monitored him continuously. By the next morning, he was eating, wagging his tail, and ready to go home.
Patricia called me a week later. “He’s fine,” she said, and then she cried. Not from grief this time, but from relief. She’d faced the thing that terrified her, she’d prepared for it, and her dog came through the other side.
What Jasper’s Story Teaches Us
Jasper’s successful surgery wasn’t luck. It was the result of a chain of decisions that started years earlier, when Patricia got him tested as a puppy. It continued through every vet visit where she reminded the staff of his status. It culminated in a surgical team that had the knowledge and the tools to keep him safe.
Every link in that chain mattered. Remove any one of them - the test, the documentation, the informed surgical team, the modified protocol - and the outcome might have been very different.
This is what advocacy looks like. Not confrontation. Not distrust. Just steady, consistent, informed participation in your dog’s medical care. Knowing the right questions. Insisting on the right answers. Being present, being prepared, and being the voice your dog can’t have for himself.
A Final Word on Fear
I understand the fear. Believe me, I understand it. After Cooper, I couldn’t walk into a vet’s office without my heart racing. Every medication was a potential threat. Every procedure was a potential disaster. Fear is a rational response to having lived through - or learned about - the worst-case scenario.
But fear that paralyzes you isn’t protecting your dog. It’s endangering them. A dog who needs surgery and doesn’t get it because their owner is too afraid of anesthesia complications is a dog who suffers unnecessarily. The mass grows. The dental disease progresses. The condition worsens.
Preparation is the antidote to fear. When you know the protocol, when you’ve asked the questions, when you’ve confirmed the plan, when you’ve chosen a competent team - you’ve done everything within your power. The rest is in skilled hands.
Jasper is twelve now. Patricia sent me a photo last week - him lying on a plaid blanket in a patch of winter sunlight, his scar barely visible under his coat. He looked peaceful. He looked like a dog who was loved enough to be protected, and trusted enough to be given the care he needed.
That’s what we’re all trying to do here. Love them enough to learn. Trust enough to act. Prepare enough to let the fear become something smaller than the love.
This guide is for educational purposes and does not constitute veterinary medical advice. Anesthesia protocols should be determined by a licensed veterinarian based on your individual dog’s health status, age, and specific medical needs. If you have questions about your dog’s upcoming surgery, please consult with your veterinary team. You can also reach out to us for support and additional resources.