What happens during anesthesia for my pet?
Prior to any anesthesia some type of blood work is checked. This can be performed at your regular veterinarian’s clinic or in our hospital. The blood work evaluates major organ function (i.e. liver and kidneys) and looks for any evidence of infection or other major diseases (i.e. diabetes, pancreatitis, etc.). If everything looks fine on the blood work evaluation and surgery is indicated following your pet’s consultation then general anesthesia will be performed.
Anesthesia starts with premedications (a.k.a. premeds). Animals are generally given the combination of a sedative and a pain medication as a premed. This helps to calm your pet and reduces any stress associated with the induction of anesthesia. Fifteen to twenty minutes following the administration of the premedication an intravenous (IV) catheter is placed in all animals undergoing general anesthesia. The catheter allows us to administer an induction agent, which is needed to begin general anesthesia. The IV catheter also allows us to deliver pain medications to your pet and administer intravenous fluids to support major organ function during and following surgery. Finally the catheter allows us to deliver life saving drugs and fluids in case there is a major complication during or after surgery.
Following placement of the catheter an induction agent is given which allows us to place an endotracheal tube. The induction agents are generally very short acting. Maintenance of general anesthesia is provided through the inhalation of an anesthetic gas and 100% oxygen combination delivered from an anesthesia machine.
A licensed veterinary technician continually monitors all animals that are placed under general anesthesia. Vital sign measurements are recorded every 5-10 minutes on an anesthetic flow sheet. Anesthetic parameters and vital signs that are monitored included heart rate, respiratory rate, blood pressure, electrocardiogram (i.e. ECG), end tidal carbon dioxide (a.k.a. ETCO2), blood oxygenation (a.k.a. pulse oximetry) and body temperature. The vast majority of animals are maintained on a ventilator during anesthesia to ensure a consistent supply of anesthetic gas and maintain ventilatory or lung function.
Following the completion of the surgical procedure a licensed veterinary technician stays with each animal until they are completely awake and breathing comfortably on their own. At that point they are transferred to the intensive care unit and will be closely monitored until their body temperature has returned to normal and they are resting comfortably on their own. They are then monitored at least hourly for the remainder of the day and overnight by the overnight hospital staff. Immediately following surgery and overnight the vast majority of anesthetized patients will be on intravenous fluids and injectable pain medications. Once adequately awake animals will be given a chance to walk outside with assistance.
How will pain be controlled for my pet?
All animals will receive some type of pain medication with surgery. Pre anesthetic medications used for sedation generally contain an opioid pain medication (i.e. morphine or something similar). Most animals will also receive a C.R.I. or constant rate infusion of a combination of pain medications during the surgical procedure. This C.R.I. will generally be continued overnight to deliver constant pain relief to our surgical patients while they recover from anesthesia. The advantage of a C.R.I. is that it can be delivered faster if a particular animal seems painful or slower if an animal seems to be too sedate. This provides maximum control to minimize pain for our patients. Most animals will also receive an injectable anti-inflammatory medication soon after their recovery from anesthesia. This helps to control pain as well. Other means that are commonly used to minimize pain include epidurals regional nerve blocks and pain patches.