GUIDE TO UNDERSTANDING ANESTHESIA IN HORSES
Studies have shown that less than 0.1% of horses undergoing anesthesia experience complications that are fatal. The dedicated and caring professionals at MSU VMC provide the highest level of care for your horse before, during, and after anesthesia. With our careful preparation, proven techniques, and impeccable attention to detail, the possibility of an adverse event is low.
General Anesthesia in the Horse
There are risks associated with any anesthetic and surgical procedure, and because of their large size and athleticism, horses require special handling during anesthesia. Your horse receives one-on-one care from their anesthesia provider from the moment they are anesthetized until they recover and stand back up.
The Process
1) A small area of hair on the neck is clipped and a catheter is placed in the jugular vein for administration of medications and IV fluids.
2) The horse is sedated.
3) The horse is taken into a padded stall for induction of anesthesia. A swing gate helps ease them to the ground.
4) A tube is placed into the trachea for administration of anesthetic gas and oxygen.
5) We carefully monitor the horse using blood pressure, ECG, pulse oximeter, capnograph, and blood gas analysis.
6) Recovery occurs in a padded recovery stall.
Specific Anesthetic Complications
Even with expert care, serious complications affect approximately one in one thousand horses that are anesthetized. Although adverse events are rare, we feel it is important to outline some of the most significant of the potential complications.
Recovery problems: Stumbling, incoordination, or falling can cause:
- Abrasions
- Lacerations
- Joint injuries
- Rarely, fractured bones.
Risk management: The recovery stalls are well padded. Horses are observed until they are standing. Sedation and rope assistance are provided as needed.
Paralysis: Young draft horses are at particular risk.
Risk management: Blood pressure support, good padding, minimize down time.
Nerve Damage: Horses cannot stand on the affected limb. Some recovery of nerve function usually occurs, but may take weeks to months.
Risk management:
- Proper positioning
- Thick pads made of high density foam in surgery and recovery
Myopathy: Heavily muscled horses, those who have recently exercised, or with a history of cramping or HYPP are at increased risk of muscle damage during surgery.
Risk management:
- Proper positioning
- Blood pressure support
- Thick pads made of high density foam in surgery and recovery
Other Uncommon Complications: Very rarely encountered problems that may also occur include allergic reaction, cardiac arrhythmias, laryngeal paralysis and airway obstruction, hypoxia, pulmonary edema, aspiration pneumonia and sudden death.
Horses at Increased Risk for Problems
- Draft breeds
- Impressive-bred (quarter horses)
- Heavily muscled
- Pregnant and foaling
- Airway surgery
- Colic surgery
- Fit athletes
Potential Complications of Anesthesia in the Horse
- Corneal ulceration
- Upper airway obstruction
- Pulmonary aspiration
- Myopathy/Neuropathy
- Long bone fracture
- Paralysis
- Anaphylactic reaction
- Sudden death
Some of these complications may require humane euthanasia
Source : msu.edu