TAP Using Dexmedetomidine and Ropivacaine for Cesarean Section Analgesia

Study Overview
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Brief Summary
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To evaluate the effect of dexmedetomidine as an adjuvant of ropivacaine in the TAP block on cesarean section parturients under multimodal analgesia, optimize the multimodal analgesia program for cesarean section, and guide perioperative analgesia managemen。This is a single center, double-blind, randomized clinical trial.

Official Title
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Effect of Dexmedetomidine Combined With Ropivacaine Transverse Abdominal Plane Block (TAP) on Opioid Dosage After Cesarean Section Under Multimodal Analgesia

Conditions
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Multimodal Analgesia, Cesarean Section

Intervention / Treatment
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* Drug: Dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1) 37-42 weeks of gestation 2) Plan cesarean section 3) Receiving patient controlled intravenous analgesia 4) Age>18 years 5) ASA（American Society of Anesthesiologists) grade I-III 6) Voluntary participation and informed consent Exclusion Criteria: 1)The anesthesia method for cesarean section is general anesthesia or intraspinal anesthesia, and epidural administration is used 2) Combined with other opioids during operation 3) High risk pregnancy (multiple pregnancy, in vitro pregnancy, etc.) or pregnancy related complications (hypertension, preeclampsia, chorioamnionitis, etc.) 4) Times of previous cesarean section ≥ 3 5) BMI ≥ 50kg/m2 is not suitable for TAP block 6) Allergies or contraindications to the drugs involved in the study 7) Combined with operations other than tubal ligation and ovariectomy 8) Severe renal function impairment (SCR>176 µ mol/L and/or blood urea nitrogen>17.9 mmol/L), severe liver function impairment (ALT and/or aspartate aminotransferase exceed 3 times the upper limit of normal value) 9) Increased risk of coagulation dysfunction or bleeding (PLT<80 × 109/L or international normalized ratio> 1.5) 10) History of chronic pain or opiate abuse 11) Other clinical trials in the last three months

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: dexmedetomidine + ropivacaine<br>each side dexmedetomidine 0.5ug/kg+0.25% ropivacaine 20ml TAP block | Drug: Dexmedetomidine<br>* each side dexmedetomidine 0.5ug/kg TAP block<br>|
| No Intervention: ropivacaine<br>each side 0.25% ropivacaine 20ml TAP block | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Consumption of hydromorphone | Consumption of hydromorphone 48 hours after surgery | 48 hours after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Consumption of hydromorphone | Consumption of hydromorphone 24 hours after surgery | 24 hours after surgery | 
| First time to press bolus | Time between end of surgery and first time to press bolus | 48 hours after surgery | 
| Attempts of pressing bolus | Attempts of pressing bolus at 4 hours, 12 hours, 24 hours and 48 hours after surgery respectively | 48 hours after surgery | 
| Numeric Rating Scale | Numeric rating scale sores at rest , ambulation and uterine contraction. Postoperative pain will be scored on a scale of 0 to 10 on the NRS, with nil (0) representing no pain and 10 representing the worst imaginable pain. | 48 hours after surgery | 
| Postoperative satisfaction | Self-planned satisfaction with postoperative analgesia 0 point: dissatisfied, persistent pain, unable to sleep; point: satisfied, slight pain, pain when breathing deeply or coughing; points: very satisfied, painless when breathing deeply or coughing, quiet to sleep | 48 hours after surgery | 
| Postoperative Ramsay score | It divides a patient's level of sedation into six categories ranging from severe agitation to deep coma. Level 1 sober: the patient is anxious, restless or irritable; Level 2 sober: the patient is cooperative, has good orientation or is quiet; Level 3 sober: the patient only responds to commands; Level 4 sleep: the patient responds quickly to light tapping between the eyebrows or strong sound stimulation; Grade 5 sleep: the patient is slow to respond to light tapping between the eyebrows or strong sound stimulation; Grade 6 sleep: the patient has no response to light tapping between the eyebrows or strong sound stimulation. | 48 hours after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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dexmedetomidine, transversus abdominis plane block