Best Practices For Surgery on USDA Covered Species (non rodent)
Pre-Surgical Planning
Pre-surgical planning should include input from all members of the surgical team (e.g. the surgeon,
anesthetist, veterinarian, surgical technicians, animal care staff, and investigator). The plan should
identify personnel involved to ensure their roles are clear and training needs have been met. Equipment
needs and supplies should also be identified for any procedures planned. A pre-operative animal health
assessment can be a key part in improving the likelihood of success for a procedure. Animals should be
healthy and acclimated to the environment to be considered an acceptable surgical candidate. Overly
stressed and/or unhealthy animals make poor surgical subjects and are more likely to develop anesthetic
or post-surgical complications. ULAR recommends an acclimation period of 5 days prior to use for
survival experiments. Euthanasia/tissue harvest and non-survival surgeries are permitted the day of
arrival; however, the PI is advised to consider the potential effects of shipping stress resulting in
confounding experimental data.
Record Keeping
Investigators are responsible for maintaining accurate records of anesthesia, surgery, and post-operative
care (including analgesic administration). Only blue or black ink should be used for notations in medical
records to allow for clear communication and ease in photocopying as information is considered public
information, available on request. A single line should be used to mark through errors in the record with
the initials provided. Records must be kept near the animal so that they are readily available for
inspection by federal regulatory agencies and veterinary staff. Anesthesia and post-operative records are
available for download at http://ular.osu.edu/forms/. These are examples only; there is no requirement that
these specific forms be used. Regardless of the form(s) used, the following items should be included:



A brief description of the surgical procedure or event, noting the individuals involved i.e.
surgeon, anesthesiologist, post-op technician, etc.
All drugs administered to each patient noting the dose, time, and route of administration, as well
as any adverse reaction to a drug or drug combination.
Clear documentation of monitored parameters during anesthetic events and post-operative period
until incisions have healed.
Please note: If an anesthesia event lasts less than 30 minutes, separate anesthesia and post-op records are
not required. A notation in the medical record would be sufficient, but should address the reason for
anesthesia, agents administered (anesthesia, analgesia, experimental agents), and details regarding animal
recovery.
Anesthesia/Analgesia
The selection of an anesthetic regimen is based on the type of procedure to be performed, species of
animal, compatibility with the experimental design and availability of appropriate equipment/facilities.
Anesthetic recovery can be rapid for gas agents and short anesthetic episodes. Recovery time can be
prolonged when animals are under anesthesia for a long time or when injectable agents are used
Anesthesia provides a loss of feeling or pain during the surgical procedure, but does not provide residual
pain relief. Analgesia must be provided as stated in the IACUC protocol. If the planned pain
management is not sufficient based on observation and/or physiologic parameters, changes can be made
in consultation with a ULAR vet. Pain adversely impacts the welfare of animals and if not controlled, is a
variable that can confound the interpretation of experimental results.
Aseptic Technique
Aseptic technique refers to methods used to reduce microbial contamination to the lowest possible
practical level. No procedure, piece of equipment, or germicide alone can achieve that objective as it
requires the input and cooperation of everyone who enters the surgery area. This technique includes
preparation of the patient and surgeon, sterilization of the instruments, supplies, and implanted materials,
and the use of intraoperative techniques to reduce the likelihood of infection.
Preparation of the Surgical Environment
Surgical facilities should be sufficiently separate from other areas to minimize unnecessary traffic and
decrease the potential for contamination. The functional components of the space (surgical support,
animal preparation, surgeon’s scrub, operating room and postoperative recovery) would ideally have
physical barriers but distance between areas and/or timing of cleaning and disinfection of the space can
also achieve such separation. Control of contamination and ease of cleaning should be key considerations
in the design of a facility. Ventilation systems supplying filtered air at positive pressure can reduce the
risk of post-operative infection. Careful location of air supply and exhaust ducts and appropriate room
ventilation rates are also recommended to minimize contamination. Operating rooms should have little
fixed equipment. Other features to consider include surgical lights to provide adequate illumination;
sufficient electric outlets for support equipment, gas to support anesthesia, surgical procedures, and gaspowered equipment; vacuum, and gas-scavenging capability. If it is necessary to use an operating room
for other purposes, it is imperative that the room be returned to an appropriate level of hygiene before its
use for major survival surgery.
Preparation of the Surgical Equipment
Only sterile solutions are to be used for injectable anesthetics, fluids, or analgesics. Many supplies such
as surgical suture, gloves, catheters, and syringes, are commercially available in sterilized packs;
however, it is generally necessary to arrange for the sterilization of surgical instruments, implanted
materials, drapes, and other equipment. For additional details, see Disinfectant and Sterilization
Recommendations. Sterilization indicators should be used to validate that materials have been properly
sterilized. All sterile instruments and equipment should be placed on a sterile surface, such as a drape.
This provides a sterile workspace for the surgeon.
Preparation of the Surgeon
All members of the surgical team should be familiar with the procedures required to don needed personal
protective equipment; surgical face mask, bonnet, a sterile surgical gown and sterile surgical gloves. In
order to effectively perform a surgical scrub, it is recommended that a sink be available with an electriceye or foot/knee pedal but additional support staff can assist in this capacity. For appropriate hand
preparation, a 2-5 minute minimum scrub using long acting antimicrobial soap is recommended in
addition to proper drying of hands using a sterile towel.
Preparation of the Animal
An ophthalmic lubricant (e.g. Puralube®) should be applied to the animal’s eyes after sedation to prevent
drying of the cornea. Hair/fur should be removed from at least 1 cm on all sides of the intended surgical
site. Note that a separate area should be designated for animal preparation so as to prevent contamination
of the surgical area. Hair/Fur is typically removed with electric clippers or a razor. When scrubbing the
surgical site, begin at the center of the site and circle out toward the periphery. Sterile drapes help to
maintain a sterile field and preserve body heat. While drapes play an important role in reducing
contamination of the surgical site, faulty technique may increase contamination.
Intra-operative Animal Care
To help maintain core body temperature, the animal should be laid on an insulated material, such as a
clean surgical towel, for surgery preparation, surgery, and recovery. A circulating warm water or
microwavable heating pad can be used underneath the towel or drape to provide heat support. Do not use
electric heating pads on animals during surgery because of their irregular heating and potential to cause
thermal burns to the animals.
Anesthetic depth of the animal during surgery must be closely monitored. A general indicator of
adequate anesthesia is the animal’s lack of response to painful stimuli and/or jaw tone although
physiologic parameters such as heart rate and respiratory rate may also indicate anesthetic depth.
Electronic monitors are commonly used to measure oxygen saturation, heart rate and rhythm, and
respiratory rate and allow for emergency alarms when measurements are outside the ideal range. At a
minimum, continuous awareness of respiratory rate, heart rate and rhythm during anesthesia, along with
gross assessment of peripheral perfusion (pulse quality, mm color and CRT) are recommended.
Assessment of oxygenation should be done whenever possible by pulse oximetry, with blood gas analysis
being employed when necessary for more critically ill patients.
Wound Closure Materials
Suture and staples are most commonly used to close surgical incisions. For additional information
regarding wound closure and suture materials, please review the Wound Closure Guidelines and
Recommendations
Post-Operative Animal Care
Monitoring in recovery should include at the minimum evaluation of pulse rate and quality, mucous
membrane color, respiratory pattern, signs of pain, and temperature. Supportive equipment will depend
on the species and the types of procedures but it should be designed to be easily cleaned and to support
physiologic functions, such as thermoregulation and respiration.
Multiple Surgical Procedures
Major survival surgery refers to a surgical intervention that penetrates and exposes a body cavity or any
procedure which produces permanent impairment of physical or physiological functions, such as
laparotomy, thoracotomy, joint replacement, limb amputation. Animals recovering from minor surgical
procedures (wound suturing, peripheral vessel cannulation, percutaneous biopsy) typically do not show
significant signs of post-operative pain, have minimal complications, and return to normal function in a
relatively short time.
Multiple major survival surgeries on a single animal must be clearly described and scientifically justified
in the animal use protocol and approved by IACUC. Regardless of the classification, multiple surgical
procedures on a single animal should be evaluated to determine their impact on the animal’s well-being.
For further information:
Surgery in USDA species (non-rodent) Policy
Disinfectant and Sterilization Recommendations
Wound Closure Recommendations
References:
1.
2.
3.
4.
5.
The Guide for the Care and Use of Laboratory Animals. 8th Edition. NRC. 2011.
USDA Policy # 3: Veterinary Care
USDA Policy #14: Major Survival Surgery Dealers Selling Surgically-Altered Animals to Research
The Animal Welfare Act and Regulations, USDA
ACVA (American College of Veterinary Anesthesiologists) Small Animal Monitoring Guidelines Update,
2009