In the morning of the procedure, your pet will have a full veterinary examination. A blood sample is taken for a pre-anaesthetic blood test. The pre-anaesthetic blood test gives us an indicaiton of your pets kidney and liver health, protein and sugar levels and red blood cell count prior to anaesthesia. When there are abnormalities in the pre-anaesthetic blood test, this may alter the type of anaesthesia or fluid therapy or we may need to give fluids for a day before or after the procedure. Sometimes we need to do further tests or treatment before proceeding with anaesthesia.
Once we have the results of the blood test, we can formulate an anaesthetic protocol for you pet. First we give a pre-medicaton injection. The pre-med contains a mild tranquiliser and/or an opioid for pain relief.
30 minutes after the pre-med, your pet will be very relaxed and ready for anaesthesia. The first step is to place an intravenous catheter. The catheter is used to give the induction agent - an intravenous anaesthetic agent that makes the animal fall asleep so that we can intubate. We also give intravenous fluids through the catheter during and after the anaesthetic to provide cardiovascular support to your treasured pet.
Balanced anaesthesia is the only safe method of anaesthetising an animal for any procedure. This is where we use small quantities of multiple drugs, which has the effect of significantly reducing the quantity of every drug required. Your pet has received two medications already in the pre-med. They are calm, rested, sleepy, but not asleep and cannot be intubated. The induction drug is given slowly through the IV catheter until your pet is asleep, allowing us to insert an endotracheal tube through the mouth and larynx and into the trachea.
Once intubated, your pet is attached to the anaesthetic machine and further anaesthetic is given through the endotracheal tube to keep your pet asleep. This drug is called isoflurane and delivered in 100% oxygen gas. The tube also maintains an open airway, as often when an animal is anaesthetised, the body is so relaxed that the airway can close a little bit. This endotracheal tube will remain in place delivering vital oxygen to your pet until your pet is awake at the end of the procedure.
Monitors are attached to your pets tongue (or ears in light coloured animals) and hind limbs allowing us to monitor oxygenation, heart rate, body temperature and blood pressure. No electric monitor is better than a real live human, which is why there is also a fully qualified Veterinary Nurse monitoring your pet throughout the anaesthetic.
We have lots of patients under 10kg (and some less than 1kg) requiring anaesthesia. Small patients can lose heat very quickly under anaesthetic. Add to this the extra water that is flying around during the dental and becoming cold can be a big problem. Heating pads and hot water bottles can be dangerous due to risk of burns. We use a hot air blanket to provide warmth to all patients under anaesthetic. Hot air blankets are considered the safest method of providing warmth to anaesthetised patients and are used in human hospitals throughout the world. Thermostatically controlled warm air is forced into the blanket. Most of our patients lose no heat during their anaesthetic. When patients are warm, the anaesthetic is more stable and the patient wakes up faster and more comfortably.
Once the monitors are attached, the blanket is in place, IV fluids are started, the patient is asleep and the nurse has indicated the patient is ready, the dental can commence. This is a before photo, showing grade 2-3 dental disease in a 4.4kg chihuahua.
Every surface of the patients teeth is cleaned with the ultrasonic scaler. We also use the ultrasonic scaler to clean the peridontal space - generally only a few mm deep - the peridontal space lies between the gum and the tooth. The first scale is done with normal dsitilled water. Once the mouth is clean and any extractions are completed, we do a second scale with an antiseptic solution.
We do not like extracting teeth, anymore than you like having your pets teeth removed. However rotten teeth are painful. If rotten teeth are not removed, they remain a harbour for bacteria in the mouth and tartar can form again quickly. Some teeth are obviously cracked or have large cavities and require removal. Unlike humans, whose cavities can be filled, cats and dogs form cavities that extend below the surface of the tooth and into the root. Teeth with obvious holes or cracks needs to be removed. Sometimes teeth can look normal on the outside, but there is disease in the bone around the tooth. After scaling, every tooth in the mouth is probed with a special blunt instrument that cannot penetrate healthy tissue. This canine tooth looks fine on the outside, but the probe easily sinks into the diseased tissue around the tooth, and we will need to remove it. Luckily for this patient, the canine teeth are for catching prey and tearing at flesh. This little chihuahua does not have to hunt for his dinner tonight, and he will be much happier with this painful tooth removed.
After scaling and extraction, comes polishing. We use a special polishing paste formulated especially for animals. The polishing step is very important to protect and seal the tooth after scaling.
A final check and everything looks clean. This extraction site has been sutured. Sometimes there is a lot of infection (pus) present in the tooth socket after an extraction and in this case we would leave the socket open to allow for drainage. Either way, the gum will be completely healed in 1-2 weeks.
This photo was taken only 10 minutes after turning the anaesthetic off. Obviously this patient is feeling a little sleepy after his procedure, but he has woken up calmly, he is warm, well hydrated and comfortable. He has received additional pain relief in the form of a local anaesthetic injection at the extraction site and an extra pain relief injection as he woke up. This little old man is nearly 14, so we will leave the warming blanket on him until he wants to stand up. Younger and larger patients may not need warming in the recovery cage, but this is always available if required.