Pre-Emptive Analgesia in Ano-Rectal Surgery

Summary

The perianal region is the region around the anus. Administering a pain medication before a surgery starts is called preemptive analgesia. In some studies, this technique has been shown to be an effective way to reduce the pain that a patient experiences in the post-operative timeframe to a greater extent than would be expected simply from the pain medications alone. One theory of why this occurs suggests that the preemptive analgesia desensitizes brain and nerves to pain, thereby decreasing the response to painful stimuli, like surgery when they occur. This leads to a decrease in the amount of narcotic pain medication required after the procedure, which leads to less side effects and a quicker return to normal functioning. As perianal surgeries do not usually include a long stay in the hospital, controlling post-procedure pain is a priority.

The use of preemptive analgesia is in other types of surgeries, such as orthopedics, is well established, but as the perianal region has not been well studied, its use is not the standard of care. This type of analgesia uses a combination of medications that are already in use for post-operative and non-operative pain control and administers them orally prior to the patient undergoing general anesthesia. The side effects of the medications are the same as if they had been given after surgery or for non-surgical pain.

The concept of preemptive analgesia is established in other types of surgeries and it has solid basic science to support its use. The purpose of this randomized, double-blind, placebo controlled study is to determine if patients undergoing perianal surgeries could benefit from preemptive pain control. The primary outcome will be whether patients experience less post-operative pain. Patient post-operative consumption and latency until use of narcotic pain medication will be the secondary outcomes. The investigators believe that the patients receiving pain medications before their operation will require less pain medication after surgery, with minimal increased risk to the patient.

Conditions

• Hemorrhoids
• Fissure in Ano
• Rectal Fistula
• Anal Condyloma

Interventions

DRUG

Gabapentin

DRUG

Ketamine

Prior to the incision in the operating room, the anesthesiologist administers 0.15 mg/kg of ketamine IV push in patients randomized to the experimental arm, only.

DRUG

Acetaminophen

DRUG

Dexamethasone

Prior to the incision in the operating room, the anesthesiologist administers 8 mg of dexamethasone IV push in patients randomized to the experimental arm, only.

DRUG

Placebo

Sponsors & Collaborators

• American Society of Colon and Rectal Surgeons

  collaborator OTHER

• University of Vermont

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

QUADRUPLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2014-06-30

Primary Completion

2017-05-31

Completion

2017-05-31

Countries

• United States

Study Locations