Tailored PCA Based on Preoperative Pain Sensitivity

Study Overview
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Brief Summary
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Opioids via intravenous patient-controlled analgesia (IV PCA) are widely used for postoperative pain control. However, effective pain control with minimized side effects of analgesic agents is still challenging. Several studies reported that preoperative pain sensitivity measured by quantitative sensory test could predict postoperative pain. Therefore, the investigators planned this trial to evaluate the effectiveness of tailored patient-controlled analgesia based on preoperative pain sensitivity measured by pressure pain threshold in patients undergoing gynecological surgery.

Official Title
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The Effectiveness of Tailored Patient Controlled Analgesia Based on Preoperative Pain Sensitivity in Gynecological Patients

Conditions
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Analgesia, Patient-Controlled

Intervention / Treatment
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* Other: Tailored regimen of IV PCA according to pain sensitivity
* Other: Regimen of IV PCA without considering pain sensitivity


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients scheduled to undergo elective gynecological surgery under general anesthesia patients scheduled to use IV PCA for postoperative analgesia patients with American Society of Anesthesiologists (ASA) physical status classification I, II, III Exclusion Criteria: contraindication to fentanyl use inability to communication age less than 18 years, or more than 80 years body weight less than 40kg, or more than 90kg morbid cardiovascular disease pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

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
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Tailored group<br>Tailored regimen of IV PCA according to pain sensitivity The regimen of IV PCA will be determined according to preoperative pain sensitivity of patients. Pressure pain threshold will be measured preoperatively in these patients using pressure algometer. Patients with low pain threshold will use high dose IV PCA containing fentanyl 1500mcg, while patients with high pain threshold will use low dose IV PCA containing fentanyl 1000mcg. | Other: Tailored regimen of IV PCA according to pain sensitivity<br>* In tailored group, fentanyl dosage in IV PCA will be determined according to preoperative pain sensitivity. In control, group, fentanyl dosage in IV PCA will be determined without consideration of patient's pain sensitivity.<br>|
| Sham Comparator: control group<br>Regimen of IV PCA without considering pain sensitivity The regimen of IV PCA will be determined according to experimental group patient assignments. Pressure pain threshold will not be measured in these patients. Patients will use IV PCA with fentanyl 1000mcg or fentanyl 1500mcg. The determination will be paired to assignment of experimental group. | Other: Regimen of IV PCA without considering pain sensitivity<br>* In control group, regimen of IV PCA will be determined without consideration about patient's pain sensitivity.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative nausea | Incidence of postoperative nausea | during the postoperative 3 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative pain scores | numeric rating scale | during the postoperative 3 days | 
| incidence of postoperative vomiting | incidence of postoperative vomiting | during the postoperative 3 days | 
| Severity of postoperative nausea | numeric rating scale | during the postoperative 3 days | 
| Incidence of other postoperative adverse effects | itching sense, urinary retention, drowsiness, dry mouth, sweating, respiratory depression | during the postoperative 3 days | 
| cumulative dose of drug that infused via IV PCA | cumulative dose of drug that infused via IV PCA | during the postoperative 3 days | 
| Incidence of IV PCA clamping | Incidence of IV PCA clamping | during the postoperative 3 days | 
| rescue analgesics | amount of administered rescue analgesics | during the postoperative 3 days | 
| antiemetic agents | amount of administered antiemetic agents | during the postoperative 3 days | 
| satisfaction score | Patient's satisfaction with postoperative analgesia (0:totally unsatisfied and 100: totally satisfied) | during the postoperative 3 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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fentanyl, Pain Threshold, predicted