Standard on Pain Identification and Post-Operative Analgesia

Title

University of North Carolina at Chapel Hill Standard on Pain Identification and Post-Operative Analgesia

Introduction

Purpose

The standards and procedures described below provide guidance to all researchers and animal handlers regarding identification of pain in animals and appropriate analgesia for post-operative and Pain Category D procedures to prevent pain.

Scope

This Standard applies to all personnel engaged in the care and husbandry of animals and laboratory members administering post-operative analgesia and/or performing post-operative monitoring.

The University of North Carolina at Chapel Hill ("UNC-Chapel Hill" or "University") Institutional Animal Care and Use Committee (IACUC) expects that anyone involved in animal work at the University will comply with this Standard. Requests for exceptions to this Standard must be reviewed and approved by the IACUC.

Standard

In order to alleviate pain and/or distress post-operatively, the IACUC requires the administration of analgesics for all survival surgeries. Selection of the appropriate analgesic agent(s) should be based on the type of surgical procedure, be provided for a minimum of 24 hours to 48 hours based on species and type of procedure (see DCM formularies) and continued longer if the animal is displaying any symptoms associated with pain. Those in contact with animals post-operatively should be familiar with the potential signs associated with pain or distress to ensure analgesia is provided as needed (refer to table and links at the end of this standard as well as species-specific literature).

Dependent on the procedure, different forms of anesthesia may be utilized to alleviate pain. A major surgery may require the administration of a narcotic agent such as Buprenorphine (Buprenex®) for adequate pain control and/or relief. Non-steroidal anti-inflammatory agents such as carprofen or meloxicam may be suitable for major or minor surgeries. Combinations of analgesics may be recommended, in order to provide multimodal analgesia, particularly for major surgeries. Depending on the procedure, administration of a local anesthetic, such as lidocaine or bupivacaine, may aid in pain reduction.

Note: Sedatives (able to reduce irritability/excitement) and anxiolytics (able to prevent or reduce anxiety) do not relieve pain. However, they may be used in conjunction with appropriate analgesics to provide an appropriate level of restraint or surgical anesthesia..

The US Department of Agriculture and Public Health Service policies require proper documentation of animal care and use to assess compliance with research protocols and clinical care procedures. UNC-Chapel Hill specifically requires the use of the pink "Post-Operative Monitoring/Analgesia" cards on all post-operative cages receiving monitoring or analgesia. Cards must be kept on the cage during the specified monitoring or analgesia period described within the protocol. The lab may utilize these cards as the required documentation for all observations and treatments performed during the post-operative period. Dates and times (including AM/PM) of all time-sensitive observations or treatments (post-operative evaluations, pain medication) must be recorded. If these cards are the only documentation of the post-operative analgesic administration, they must be kept with the lab’s surgery records for review and made available during inspections.

Written records are a standard form of documentation which verify experimental procedures and protocol compliance. As part of an effective animal care and use program, research personnel working with animals must develop and maintain accurate study records. Specific parameters (body weight measurements, clinical signs, tumor size, etc.) outlined in an approved protocol must be documented with attention given to the type of monitoring, frequency, and duration outlined in the approved protocol (e.g., the statement in the approved protocol "We will monitor the animal daily after surgery," requires written documentation of the daily observation.)

Regulatory and accrediting agencies expect proper documentation of animal care and use as a means for the institution to ensure compliance with research protocols and clinical care procedures. The extent of records varies based on the nature of the procedure. However, at a minimum, records of the procedure must consist of:

• Animal /cage/group ID;
• date of procedure;
• type of procedure;
• anesthetics/analgesics used (dose, route, and time);
• anesthesia chart (verification of toe pinch);
• drugs given (dose, time); and
• general procedures (e.g., intubation, beginning and end of surgery, etc.).

See the UNC IACUC Rodent Anesthesia/Analgesia/Procedure Record.

Exceptions

Requests for exceptions to this Standard must be reviewed and approved by the IACUC.

Definitions, Table and Links for Reference

• AWA: Animal Welfare Act
• ACLAM: American College of Laboratory Animal Medicine
• ILAR: Institute for Laboratory Animal Research
• NIH: National Institutes of Health
• Distress: the biological responses an animal exhibits in an attempt to cope with a threat to its homeostasis.
• Non-survival Surgery: Surgical procedure where an animal is euthanized before recovery from anesthesia.
• Major Survival Surgery: Surgical procedure that penetrates and exposes a body cavity. This also includes procedures that induce substantial impairment of physical or physiologic functions (such as laparotomy, thoracotomy, joint replacement, and limb amputation), or involves extensive tissue dissection or transection.
• Minor survival surgery: does not expose a body cavity and causes little or no physical impairment.

Please see chapter 3 of the following document for additional species-specific information on pain assessments in laboratory animals:

• National Research Council. (2009.) Recognition and Alleviation of Pain in Laboratory Animals. Washington, DC: The National Academies Press.

The following links provide pictorial examples of pain in rats, mice, and rabbits:

• The Mouse Grimace Scale
• The Rat Grimace Scale
• The Rabbit Grimace Scale

Related Requirements

External Regulations and Consequences

• Animal Welfare Act: Page 58, §2.31(d)(iv)(A)
• Guide for the Care and Use of Laboratory Animals (8th ed.), Veterinary Care: Pages 120, 121, 122, 123

University Policies, Standards, and Procedures

• Anesthesia & Analgesia Formularies by Species & Rodent Procedure Regimens
• For more detailed guidance, please refer to the University Policy on the Care and Use of Vertebrate Animals for Research, Training and Teaching Purposes.

Contact Information

Important Dates

• Effective Date and title of Approver: January 2011; UNC IACUC
• Revision and Review Dates, Change notes, title of Reviewer or Approver: April, 2014, June 2018; UNC IACUC

Approved by: UNC IACUC