Demystifying General Anesthesia: Part II, General Anesthesia

September 11, 2012

In my previous blog, I wrote about the steps leading up to general anesthesia designed to minimize anesthetic risk. This blog continues with medications used prior to the anesthetic agent and concludes with recommendations for pet owners.

Premedications

Successful anesthesia is not just about the main inhaled or injected anesthetic agent. Most times, several drugs are administered in the hours or minutes prior to induction of anesthesia. These drugs reduce the amount of anesthetic agent required, calm the patient, and make the process better for everyone involved. If postoperative pain is anticipated, pain management may be initiated during this period.

Induction and anesthesia maintenance drugs

After the premedications take effect, administration of an agent to induce anesthesia begins. Sometimes the same drug is used to maintain anesthesia for the procedure; other times a second maintenance agent is administered. Typically a breathing tube is secured in place to allow free passage of oxygen and anesthetic gas into the lungs and carbon dioxide out. The breathing tube has a little expandable balloon cuff which acts as a safety feature. The cuff is expanded to prevent aspiration of saliva or stomach contents into the lungs during the procedure.

Emergency preparedness

Nearly every veterinary hospital has a poster of drug doses to be used in emergency situations. At The AMC, we calculate the exact dose of a long list of emergency medications for every patient undergoing anesthesia. The paper stays with the pet throughout the anesthetic procedure. Emergency equipment is also available in the anesthesia area, including tracheal suction and defibrillators. During every procedure, heart rate, respirations, blood pressure, and blood oxygen level are recorded every few minutes, so if a negative trend is occurring it can by recognized and corrected immediately.

Recovery period

The most critical time in anesthesia is the three hours following discontinuation as this is when the most anesthetic-related deaths occur. Pets are carefully monitored until they are fully awake, once again able to swallow and ambulate normally. Here is a description of Spencer in The AMC’s recovery room.

The pet owner’s role

In addition to asking questions about the procedure and understanding the precautions your pet’s veterinary team is taking to safeguard your pet, you have other important roles. Following your veterinarian’s directions about withholding food and water before the procedure are critical in safeguarding your pet’s health. A full stomach could result in vomiting, leading to aspiration pneumonia.

In most hospitals, you will be asked to sign an informed consent document only when you understand the procedure, its risks, and have had the opportunity to ask questions of the veterinary staff. Finally, if your veterinarian recommends your pet stay overnight and recover under their supervision, listen and heed their advice. On the few occasions I have given in to client pressure and released a pet before I wanted to, both the client and I regretted it. Leaving your pet overnight allows the team to adjust the pain medications, while taking her home means she waits until morning if the prescription needs adjustment.


Fracture Repair in Dogs and Cats

July 21, 2011

A couple of weeks ago I was interviewed by a reporter about pet owner administered first aid for dogs and cats when an injury may have resulted in a fractured bone. The article has good information for pet owners to read now in preparation for a potential emergency in the future. This blog post will pick up where that article left off and explain the fracture repair techniques used by veterinary surgeons The Animal Medical Center.

For the veterinarian, the critical piece of successful fracture management is to immobilize the fracture. This can be accomplished using one of several different methods. For some fractures, more than one method might be appropriate and for others there may be only one solution to fix the broken bone. All x-rays were taken by the AMC’s Diagnostic Imaging Service.

For centuries, fractures have been treated by immobilization using casts or splints. These days the old style plaster of Paris cast has been replaced in human medicine by plastic or fiberglass. In animals we tend to use splints of fiberglass or plastic for repair of simple fractures where the bones do not need realignment. The arrows in the photo to the right point to two toe fractures in a young dog which healed when the paw was placed in a splint.

Optimal healing of a fracture requires the joints above and below the fracture be immobilized. When the fracture occurs in a location where these joints cannot be adequately immobilized by an external bandage or cast, the fracture must be repaired internally via a surgical procedure. The x-ray to the left shows the use of two small pins in the front of the hind leg bone known as the tibia.

If a bone is fractured in multiple places or spirals along the length of a bone, a simple pin will not provide enough support to immobilize the fracture and allow healing. Shown below are before and after x-rays of a fractured arm (radius and ulna) in a dog. Notice the splint on the before films. The AMC’s Emergency Service placed the splint to immobilize the fracture until surgery could be performed. The AMC surgeons chose to repair the leg with a plate and screws since both bones of the leg were broken.

As research discovers more about fracture healing, methods of repair are changing. When possible, minimally invasive procedures are chosen as large invasive surgeries disturb the covering of the bone (periosteum), the blood clot at the fracture site and the muscles which provide the blood supply to the fracture. The AMC surgeons are using a new technique called MIPO (minimally invasive plate osteosynthesis) or percutaneous plating. This method of fracture stabilization, involves application of a bone plate through small skin incisions on either end of the fracture site. The fracture is aligned and the plate and screws are placed using guidance from a special intraoperative x-ray machine. Not all fractures are amenable to MIPO.

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This may also be found in the “Tales from the Pet Clinic” blog on WebMD.com.

For over a century, The Animal Medical Center has been a national leader in animal health care, known for its expertise, innovation and success in providing routine, specialty and emergency medical care for companion animals. Thanks in part to the enduring generosity of donors, The AMC is also known for its outstanding teaching, research and compassionate community funds. Please help us to continue these efforts. Send your contribution to: The Animal Medical Center, 510 East 62nd Street, New York, NY 10065. For more information, visit http://www.amcny.org. To make an appointment, please call 212.838.7053.

Images: AMC Diagnostic Imaging Department


National Pet Fire Safety Day

July 18, 2011

Last Friday, July 15, 2011, was National Pet Fire Safety Day. When we hear about pets and fires in the home, we often think of the dog who awakens his owner, saving lives with a warning bark about a fire in the house.

But pets are also the victims of fire. According to Pet Safety Alert, 40,000 pets are killed in fires annually, most of them in residential fires.

Every year, The Animal Medical Center provides care to pets who have been trapped in burning buildings and rescued by New York’s bravest, our friends at the NYC Fire Department.

As a pet lover, you can take action to prevent pet-related fires and to protect your pet if there is a fire.

To help firefighters find all of your pets, the folks at ADT Home Security Systems offer a free window cling to alert firefighters to the presence of pets in the home. You can request one through their website.

Firefighters want to help pets suffering from smoke inhalation, but the oxygen masks designed for humans are not shaped to fit a pet’s nose. If you are feeling philanthropic, donate a pet oxygen mask to your local firefighting team.

Pet proofing your home can help to prevent a catastrophic fire. Candles are a huge danger for pets. A wagging tail can knock a candle off the coffee table and into a pile of flammable papers. My own cat, who had a big puffy tail, swished it over a lit candle and nearly went up in flames! Space heaters and backyard grills present a hazard, as they can easily be knocked over by a pet and start a fire.

To protect the entire family, make sure your smoke detectors and carbon monoxide detectors have their batteries changed twice a year. A good time to change the batteries is when you change the clocks for daylight savings time in the spring and fall.

Like people, pets can suffer from carbon monoxide poisoning. If everyone in the family is ill and your pet is exhibiting the following signs, see your veterinarian and mention you are concerned about carbon monoxide poisoning.

  • Nausea
  • Vomiting
  • Cough
  • Loss of exercise stamina
  • Disturbances in gait

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This may also be found in the “Tales from the Pet Clinic” blog on WebMD.com.

For over a century, The Animal Medical Center has been a national leader in animal health care, known for its expertise, innovation and success in providing routine, specialty and emergency medical care for companion animals. Thanks in part to the enduring generosity of donors, The AMC is also known for its outstanding teaching, research and compassionate community funds. Please help us to continue these efforts. Send your contribution to: The Animal Medical Center, 510 East 62nd Street, New York, NY 10065. For more information, visit http://www.amcny.org. To make an appointment, please call 212.838.7053.

Photo: iStockphoto


The Pen Cap May Be Mightier than the Sword…

July 15, 2011

But it can’t beat a bronchoscope!

Barcley

One thing I love about pets is their unpredictability. You just can never guess what they will do next. Here’s the story of Barcley, the French bulldog and the nearly fatal pen cap.

The beginning seemed innocent enough: a dog playing with a bright blue highlighter pen. Suddenly, he couldn’t breathe and his owners rushed him to The Animal Medical Center. Quick administration of oxygen and a sedative by the ER staff seemed to alleviate the breathing problem enough to allow a chest x-ray to be taken.

No one would have predicted the x-ray would show Barcley’s windpipe contained what looked like the cap of the bright blue highlighter!

Barcley’s chest x-ray. Arrows point to outline of pen cap in his windpipe.

The ER staff had to think quickly and cleverly. Barcley needed anesthesia and a bronchoscope to remove the highlighter pen cap, but the standard anesthetic plan of placing a breathing tube into the windpipe was out of the question; it was already full of the highlighter cap. To further complicate matters, Barcley is a brachycephalic (short nosed) dog, a type of dog known to have a greater risk of anesthetic complications.

Dr. Stacy Burdick of The AMC’s Internal Medicine Service was called in at 1:30 am to perform the procedure which took 20 minutes, but seemed like a lifetime. She placed a small rubber tube in the windpipe to deliver oxygen and administered an injectable anesthetic agent into Barcley’s vein. Dr. Burdick cautiously advanced the bronchoscope down Barcley’s windpipe. She was worried the windpipe could have been damaged as the cap went down, or worse, the windpipe could tear when she pulled it back up.

Pen cap in windpipe

On the right, you can see what Dr. Burdick saw when the cap came into view. The cap blocked the entire lumen of the windpipe. Knowing she had to work quickly to restore the delivery of oxygen to the lungs, she passed a special grabber device through the bronchoscope, grabbed the cap and gently pulled it gently out through the mouth as she pulled out the bronchoscope.

Barcley’s life was saved from the pen cap by the mighty bronchoscope and the skilled Dr. Burdick.

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This may also be found in the “Tales from the Pet Clinic” blog on WebMD.com.

For over a century, The Animal Medical Center has been a national leader in animal health care, known for its expertise, innovation and success in providing routine, specialty and emergency medical care for companion animals. Thanks in part to the enduring generosity of donors, The AMC is also known for its outstanding teaching, research and compassionate community funds. Please help us to continue these efforts. Send your contribution to: The Animal Medical Center, 510 East 62nd Street, New York, NY 10065. For more information, visit http://www.amcny.org. To make an appointment, please call 212.838.7053.


Dogs and Cats as Diana and Orion, the Hunters

July 13, 2011

Photo: Hemera

Pet owners believe their well-fed, or more likely overfed, dog or cat should have no reason to hunt, but lately it seems my patients are on a hunting spree.

Most cat owners who allow their cats outside, become accustomed to freshly killed gifts of mice and other small rodents carefully placed as an offering on the back stoop. But this week the take has been much more substantial.

Take Francie, for example, a special needs Cavalier King Charles Spaniel on anti-seizure medication. Twice last week she captured an unidentifiable furry creature and dragged it in through the doggie door. One unfortunate victim was hauled into Francie’s crate and the other left with pride in the middle of the kitchen floor. Franice’s family was outwardly distressed over her behavior, but the diminutive “Diana” seemed pleased with her hunting success.

Dixie and Mabel, a pair of Labradors, have not been hunting because they are, of course retrievers! To their owners’ initial horror, they were about to retrieve what appeared to be a dead possum, when the possum stopped “playing possum” and safely scampered back into the woods.

The Orion of the group is Willie, a handsome black Standard Poodle. He was out romping in his yard when a fawn strolled by. He tackled the fawn and was immediately tackled by his owners, who saved the fawn and had it safely transferred to the care of a wildlife rehabilitator.

I can share all these stories with you because the pet owners called me; not to brag, but out of concern for their pet’s health. Most were concerned about the potential for rabies transmission from wildlife. This is a real concern for pet owners and just one very good reason for having your pet vaccinated for rabies. Rabies vaccines are very effective and rabies is very uncommon in vaccinated dogs and cats.

Another concern is for parasite which can be carried by wildlife and transmitted to your dog or cat. The Dianas and Orions need annual fecal examinations and routine year round parasite prevention as recommended by the Companion Animal Parasite Council.

These pet owners also called wondering how to handle injured wildlife. First, you should not attempt to touch or move injured wildlife as you may be bitten. In New York State, the Department of Environmental Conservation licenses wildlife rehabilitators who can provide assistance and care for injured wildlife. There is also a FAQ page with great information about wildlife in your yard.

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This may also be found in the “Tales from the Pet Clinic” blog on WebMD.com.

For over a century, The Animal Medical Center has been a national leader in animal health care, known for its expertise, innovation and success in providing routine, specialty and emergency medical care for companion animals. Thanks in part to the enduring generosity of donors, The AMC is also known for its outstanding teaching, research and compassionate community funds. Please help us to continue these efforts. Send your contribution to: The Animal Medical Center, 510 East 62nd Street, New York, NY 10065. For more information, visit www.amcny.org. To make an appointment, please call 212.838.7053.


Everything Old is New Again: Plague and Leprosy

July 7, 2011

Nine banded armadillo, which can carry leprosy, seen in Brooklyn’s DUMBO neighborhood at modern:ANTHOLOGY.

Last week there were two very interesting stories in the news about the intersection between people and animals. Both reported on diseases we rarely hear about anymore: plague and leprosy.

Leprosy is the older disease and has been reported since Biblical times. The first reported epidemic of plague occurred somewhat later, in the 6th or 7th century. Bubonic plague, or the Black Death, was the scourge of the Middle Ages.

Plague is an infectious disease caused by the bacteria Yesinia pestis. The usual source of Y. pestis is the rat flea, but hunting pets can contract the plague from eating infected rodents or rabbits. Even though Y. pestis is predominantly found in California, Utah, New Mexico, Arizona and Nevada, cases can be seen throughout the country if a human or pet travels to one of these areas and contracts the disease before they return home. An infected pet can, in turn, infect humans. The possibility of plague transmission is one reason prairie dogs may not make the best pets.

The name bubonic comes from the word bubo, which is a fancy word for enlarged lymph node. Wikipedia shows an illumination from a medieval Bible of sinners afflicted with buboes.

Both humans and pets with bubonic plague have enlarged lymph nodes, which are painful. Fever, malaise and non–specific flu-like symptoms are typical for plague in both humans and pets. Although last week’s plague case occurred in a dog, in general, cats are more susceptible to plague than dogs.

Leprosy was in the news too; not because of a sick dog or cat, but because of armadillos. Those prehistoric-looking armored mammals carry the leprosy bacteria, Mycobacterium leprae. Most leprosy cases occur outside the United States, but cases occur in people who have not traveled outside the USA. This finding puzzled researchers until the DNA of the M. leprae was studied. Both armadillos and humans infected with M. leprae in the USA share the same unique strain of the bacteria. This bacterium is different from the strain of M. leprae found outside the USA. The New England Journal of Medicine article concluded humans can contract leprosy from infected armadillos.

To help protect yourself and your pet from contracting diseases of wildlife:

  • Keep your pet leashed or indoors to prevent contact with wild animals which can cause serious diseases.
  • Never approach, pet or handle wildlife even if they are acting friendly.
  • If your pet is sick, always tell your veterinarian where your pet has traveled and do the same when you visit your physician. It may be just the perfect clue to the diagnosis.

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This may also be found in the “Tales from the Pet Clinic” blog on WebMD.com.

For over a century, The Animal Medical Center has been a national leader in animal health care, known for its expertise, innovation and success in providing routine, specialty and emergency medical care for companion animals. Thanks in part to the enduring generosity of donors, The AMC is also known for its outstanding teaching, research and compassionate community funds. Please help us to continue these efforts. Send your contribution to: The Animal Medical Center, 510 East 62nd Street, New York, NY 10065. For more information, visit www.amcny.org. To make an appointment, please call 212.838.7053.


Summer Noise Phobias

July 5, 2011

Lovely weather, summer holidays and a relaxed atmosphere make summer everyone’s favorite season – everyone except for dogs with noise phobias. Fireworks and thunderstorms create unexpected loud noises, frightening to many dogs and cats as well. The veterinarians at The Animal Medical Center see dogs and cats injured and lost over the Fourth of July weekend as a result of their noise phobias.

Signs of noise phobia:

Destructive behavior

  • Scratching/digging at door or wall
  • Chewing
  • Loss of housebreaking

Anxious behavior

  • Clinging to owner
  • Drooling
  • Hiding, especially cats
  • Panting
  • Expressing anal glands
  • Dilated pupils

Abnormal behavior

  • Skipping meals
  • Jumping out of windows/running out of doors
  • Shaking
  • Loss of training, i.e., not responding to commands

Home Remedies
Consider trying home remedies for noise phobia. One of my patients with thunderstorm phobia calms down if her owner wipes her fur down with a dryer sheet. Dryer sheets may decrease the buildup of static electricity caused by the impending thunderstorm. I suggest the unscented ones, since dogs don’t like smelling like an ocean breeze. Anxious dogs may feel calmer during storms or fireworks if you apply a dab of lavender oil to their ear tips. The lavender oil fragrance has calming properties and is available at health food stores and on the internet.

Noise Phobia Products

  • Along the lines of the antistatic dryer sheet is the Storm Defender Cape which has a special lining to diffuse static electricity.
  • The Thundershirt is a snug fitting dog T-shirt which some of my dog owners have used for anxiety related to car rides, veterinarian visits, as well as thunderstorms.
  • An interesting product I found is dog ear muffs, but I don’t have personal experience with them.

For additional tips on managing fireworks phobia in dogs read a previous blog, “Fireworks and Your Dog.”

If you need professional help managing noise phobias in your pet, a behavioral consult with a Diplomate of the American College of Veterinary Behaviorists can help set your dog or cat on the road to recovery.

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This may also be found in the “Tales from the Pet Clinic” blog on WebMD.com.

For over a century, The Animal Medical Center has been a national leader in animal health care, known for its expertise, innovation and success in providing routine, specialty and emergency medical care for companion animals. Thanks in part to the enduring generosity of donors, The AMC is also known for its outstanding teaching, research and compassionate community funds. Please help us to continue these efforts. Send your contribution to: The Animal Medical Center, 510 East 62nd Street, New York, NY 10065. For more information, visit www.amcny.org. To make an appointment, please call 212.838.7053.


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