Policy on Analgesic Use

• Analgesics must be provided to all animals following survival surgery unless scientific justification for withholding post-operative analgesics is provided by the investigator and approved by the IACUC, or if a veterinarian examines the animal and determines that analgesic administration is no longer necessary. In cases where post-operative analgesics cannot be administered for scientific reasons, the animals must be listed in Pain Category D (i.e., pain/distress cannot be relieved by use of anesthetics, analgesics, or tranquilizers as the use of these agents would interfere with the experimental design).
• The use of local pain-relieving drugs such as Marcaine® (bupivacaine), in addition to systemic analgesia, may be indicated for some procedures that will result in significant disruption of the skin (e.g., Alzet pump placement, catheter exteriorization), as these drugs may help to block the onset of the pain cascade due to disruption of the dermal nerve cells. Local analgesics are not intended for use in lieu of systemic analgesics, unless the withholding of systemic analgesia is scientifically justified.
• Major survival surgeries require at least 48 hours of post-operative analgesia, and then as needed if the animal still appears to be in pain. For major survival surgeries, consultation with the veterinarian should also include consideration of pre-operative analgesia. A major survival surgery is defined as any procedure that penetrates and exposes a body cavity, produces substantial impairment of physical or physiologic functions, or any procedure that requires the use of more than a single application of a short-term anesthetic.
• Minor procedures require at least 24 hours of post-operative analgesia, and then as needed if the animal still appears to be in pain.

Basis

USDA Animal Welfare Act Regulations §2.31(d)(1)(iv)(A) and (ix): “Procedures that may cause more than momentary or slight pain or distress to the animals will be performed with appropriate sedatives, analgesics, or anesthetics, unless withholding such agents is justified for scientific reasons, in writing, by the principal investigator and will continue for only the necessary period of time…Activities that involve surgery include appropriate provision for pre-operative and post-operative care of the animals in accordance with established veterinary medical and nursing practices.”

PHS Policy IV.C.1.a-b: “Procedures with animals will avoid or minimize discomfort, distress, and pain to the animals, consistent with sound research design. Procedures that may cause more than momentary or slight pain or distress to the animals will be performed with appropriate sedation, analgesia, or anesthesia, unless the procedure is justified for scientific reasons in writing by the investigator.”

Guide for the Care and Use of Laboratory Animals, p. 64: “An integral component of veterinary medical care is prevention or alleviation of pain associated with procedural and surgical protocols…Pain is a stressor and, if not relieved, can lead to unacceptable levels of stress and distress in animals. The proper use of anesthetics and analgesics in research animals is an ethical and scientific imperative… In general, unless the contrary is known or established, it should be assumed that procedures that cause pain in humans also cause pain in animals.”

Anesthesia - complete loss of sensation or feeling

General - a state of unconsciousness accompanied by loss of pain sensation and some degree of muscle relaxation over the entire body

Local - limited to one part of the body

Surgical - general anesthesia at a depth, which allows surgery to be performed without pain to or movement of the patient

Analgesia - absence of sensibility to pain; more specifically the relief of pain without loss of consciousness

The majority of this section on anesthesia came from the NIH Guidelines and is used with permission. Other sources were also consulted. Please read the information carefully. If you have questions, consult with the Attending Veterinarian.

The following pages provide tables of drugs commonly used at the National Institutes of Health (NIH) for pre-anesthesia, anesthesia, analgesia, sedation, tranquilization, and restraint of laboratory animal species.

The dosage recommendations and other data presented on the following pages are based upon current data in the literature and the professional judgment of veterinarians on the NIH Animal Care and Use Committee Subcommittee on Training. Doses published in the literature are often variable. Proper drug doses may vary greatly depending on species, strain, sex, age, physiologic status of the animal, and the level of anesthesia/analgesia desired.

Post-Operative Analgesia

Analgesia must be provided to all animals following survival surgery unless scientific justification for withholding such agents is approved by the IACUC as part of the investigator’s research protocol, or if a veterinarian examines the animal and determines that analgesic administration is no longer necessary.

A list of commonly used analgesics is included in Table 6.

Although these lists provide a ready source of information on drug doses, individuals should not use these drugs without prior experience.

The animal facility veterinarian is available for consultation and additional information.

Following Table 6 is species-specific information. Controlled drugs are identified by a “C.” The Roman numeral classifies the drug into one of the five established schedules of controlled substances (e.g., sodium pentobarbital, C-II).

Abbreviations:

IV = intravenous
IM = intramuscular
IP = intraperitoneal
SC = subcutaneous
PO = per os, oral
IH = inhalation
qXh = every X hours