Aspen Vet Warns Anesthesia Risks for Senior Pets

Aspen —Voss: Anesthesia complications.

That is the headline in the Aspen Times, and it covers a reality that pet owners across the valley face every time they bring an older dog or cat into a clinic for surgery. The piece, written by Dr. Voss, breaks down why the "routine" procedure can turn complicated and what owners should be asking their veterinarians before signing a consent form.

The core argument is straightforward: age itself isn't the enemy, but the diseases that travel with it are. "Age is not a disease; however, disease often comes with age," Voss wrote in the Aspen Times. "My older patients are more likely than younger ones to have heart disease, kidney disease or respiratory disease, all of which can increase anesthetic risk."

For folks around here who have senior pets — those golden retrievers and dachshunds that have been part of the family for a decade or more — this is less about fear and more about preparation. The physiology is unforgiving. Anesthetic gases must be inhaled and exhaled, so any respiratory issue complicates the process. The liver metabolizes the drugs; the kidneys filter them out. And the heart has to pump oxygen to every organ while those drugs alter blood pressure and vascular resistance.

The most common complication isn't dramatic in the moment, but it can be devastating later. Hypotension, or low blood pressure, is the primary concern. "When blood pressure drops too low for too long, organs such as the kidneys may not receive adequate blood flow and oxygen, potentially resulting in kidney injury," Voss wrote. "Sometimes the effects aren’t evident until days after the anesthetic event and can be severe or even life-threatening."

This is where the pre-anesthetic bloodwork comes in. It’s not just a box to check for billing purposes; it’s the diagnostic tool that tells the vet if the animal has enough physiological reserve to survive the procedure. "We use complete blood counts (CBC) and chemistry panels to evaluate blood cells and assess organ function, including the kidneys and liver," Voss wrote. "Any significant abnormalities should be investigated before proceeding with anesthesia, so we can identify potential risks and make an appropriate anesthetic plan."

The question is whether owners are actually reading those results or just trusting the vet to handle it. Voss emphasizes that even animals with no known underlying disease can experience complications if not monitored appropriately during the procedure. Continuous ECG monitoring is standard to catch arrhythmias, but a preoperative ECG can help identify existing rhythm abnormalities before the animal is even induced. For pets with heart murmurs, an echocardiogram becomes the best way to assess the heart’s structure and function.

The math holds up when you look at the stakes. The benefits of the procedure must outweigh the potential risks, but that calculation changes depending on whether your pet has a healthy heart or one that’s struggling to maintain blood pressure. Voss noted that sometimes, if a significant arrhythmia develops and cannot be safely managed, "a procedure must be postponed or stopped."

For neighbors in the valley, this means a conversation with your vet before the appointment. It’s not about avoiding anesthesia; it’s about ensuring the monitoring and pre-testing are commensurate with your pet’s age and health status. The goal is to identify the risks so they can be managed, not just discovered after the fact.

To hear them tell it, the process is a balance of vigilance and acceptance that risk can never be zero. "Although we cannot predict every event, a preoperative ECG may help identify certain existing rhythm abnormalities before anesthesia is induced," Voss wrote. "Additionally, pets with heart murmurs may need further evaluation before an anesthetic procedure."

For any pet owner in the region, the message is simple: ask about the bloodwork. Ask about the ECG. And if your pet has a murmur, ask for the echo. The details in that pre-procedure window are where safety is built or lost.