Additive Effect of Intravenous Acetaminophen on Postoperative Pain Control

Study Overview
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Brief Summary
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This study aimed to evaluate the additive effect of acetaminophen on postoperative pain control in patients receiving nefopam and fentanyl-based patient-controlled analgesia. Participants undergoing laparoscopic hysterectomy will be randomly assigned to treatment group or control group. After end of surgery, acetaminophen or normal saline (placebo) will be administered intravenously depending on the group assigned.

Official Title
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Additive Effect of Intravenous Acetaminophen Administered at the End of Surgery on Postoperative Pain Control With Nefopam and Fentanyl-based Patient-controlled Analgesia: A Double-blind Randomized Controlled Trial

Conditions
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Postoperative Pain, Gynecologic Disease

Intervention / Treatment
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* Drug: Acetaminophen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing total laparoscopic hysterectomy due to uterine myoma, cervical cancer, endometriosis, uterine prolapse Exclusion Criteria: Liver disease (aspartate transaminase OR alanine transaminase > 80 IU/L) Chronic kidney disease (GFR < 30 ml/min/1.73m2) History of drug allergy Chronic pain lasting more than 3 months Conversion to laparotomy Complex surgery (co-operation with colon surgeon or urologist) Limitation in expressing pain

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Double-blind randomized controlled trial
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Treatment<br>Patients in this group will receive 1 gram of acetaminophen intravenously after the end of surgery. | Drug: Acetaminophen<br>* Acetaminophen will be intravenously administrated to treatment group after the end of surgery.<br>* Other names: treatment;|
| No Intervention: Control<br>Patients in this group will receive 100 ml of normal saline intravenously after the end of surgery. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total volume of administered analgesics during postoperative 24 hours | morphine equivalent dose of patient-controlled analgesics administered during first 24 hours after end of surgery | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain score | 11-point numeric rating scale ranging from '0' representing one pain extreme (e.g. no pain) to '10' representing the other pain extreme (e.g. pain as bad as you can imagine or worst pain imaginable) | 24 hours | 
| Patient satisfaction score | 11-point numeric rating scale ranging from '0' representing one extreme (e.g. extremely dissatisfied) to '10' representing the other extreme (e.g. extremely satisfied) | 24 hours | 
| Postoperative nausea and vomiting | 4-scales scoring (none; mild; moderate; severe) | 24 hours | 
| Opioid-related adverse effect | Incidence of respiratory, gastrointestinal, and central nervous system complications | 24 hours | 
| Use of alternative analgesics | Additional administration of other analgesics | 24 hours | 
| Length of stay | Hospital length of stay | From date of hospital admission until the date of discharge, an average of 1 week |