A Multicenter Study: Dexmedetomidine Combined With Sufentanil for Patient Controlled Intravenous Analgesia After Caesarean Section

Study Overview
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Brief Summary
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The purpose of this multicenter study is to evaluate the effectiveness and safety of dexmedetomidine combined with sufentanil for patient-controlled analgesia after caesarean section

Conditions
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Postoperative Pain

Intervention / Treatment
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* Drug: Normal saline
* Drug: Dexmedetomidine
* Drug: Sufentanil
* Drug: Sufentanil and dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Parturients undergoing elective caesarean delivery under spinal anaesthesia American Society of Anesthesiologists class I and II parturients aged 18-45 years, with term singleton pregnancies Parturients with the ability to understand verbal and written mandarin Parturients who want to use PCA intravenous analgesia and can use the pump correctly Parturients whose written informed consent have been obtained Exclusion Criteria: A history of allergy to dexmedetomidine or other study drugs A long use history of opioid analgesic, NSAIDs, tranquilliser use Psychiatric disorders A history of neuromuscular and endocrine disease or allergic disease A history of lower abdominal surgery Preoperative heart rate (HR) less than 50 bpm, SBP less than 100 mmHg or cardiac conduction or rhythm abnormalities spinal anaesthesia was unsuccessful or an epidural catheter had to be used to achieve adequate anaesthesia A second operation is required during the study. Participating other study during the latest three months Body mass index more than 30 kg/m2 Difficult airway ( Mallampati score more than 3 and anatomic deformity ) Not suitable for participation estimated by investigation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Control Group<br>Parturients in this group receive 20ml intravenous normal saline immediately after delivery. Their patient controlled analgesia (PCA) protocol after surgery consists of 100 mcg sufentanil diluted into 100ml and administer at a background infusion of 1ml/h,and a bolus of 2ml, with a lock-out of 8min. | Drug: Normal saline<br>* Control Group receives normal saline bolus after delivery<br>Drug: Sufentanil<br>* sufentanil PCA after surgery<br>|
| Experimental: Dex Group<br>Parturients in this group receive 0.5mcg/kg intravenous dexmedetomidine diluted to 20ml with normal saline. Their PCA protocol after surgery is 100mcg sufentanil and 300mcg dexmedetomidine diluted to 100ml in saline, with the continuous infusion of 1ml/h, and a bolus of 2 ml, with a lock-out of 8min. | Drug: Dexmedetomidine<br>* Dex Group receives dexmedetomidine bolus 0.5mcg/kg after delivery<br>Drug: Sufentanil and dexmedetomidine<br>* sufentanil combined with dexmedetomidine PCA after surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sufentanil consumption | The total consumption of sufentanil during 24h after surgery are recorded. | During 24h after surgery | 
| Changes in pain score | Pain scores at rest and movement are evaluated with a visual analogue scale (VAS). | At 0, 4, 8 and 24 h after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in Ramsay sedation score (RSS) | Sedation intensity measured with RSS is recorded at the 4, 8 and 24 h after surgery. | At 4, 8 and 24 h after surgery | 
| Changes in systolic blood pressure | Systolic blood pressure is recorded at 0 min, 5 min, 10 min, 30 min after intervention during surgery and at 8h,24 h after surgery. | At 0 min, 5 min, 10 min, 30 min after intervention during surgery and at 8h,24 h after surgery. | 
| Press times of analgesic pump | The total press times and invalid press times are recorded during 24h after surgery. | During 24h after surgery | 
| Changes in heart rate (HR) | HR is recorded at 0 min, 5 min, 10 min, 30 min after intervention during surgery and at 8h,24 h after surgery. | At 0 min, 5 min, 10 min, 30 min after intervention during surgery and at 8h,24 h after surgery | 
| Changes in saturation of blood oxygen (SpO2) | SpO2 is recorded at 0 min, 5 min, 10 min, 30 min after intervention during surgery | At 0 min, 5 min, 10 min, 30 min after intervention during surgery and at 8h,24 h after surgery | 
| Changes in diastolic blood pressure | Diastolic blood pressure is recorded at 0 min, 5 min, 10 min, 30 min after intervention during surgery and at 8h,24 h after surgery. | At 0 min, 5 min, 10 min, 30 min after intervention during surgery and at 8h,24 h after surgery | 
| Changes in mean arterial blood | Mean arterial blood pressure is recorded at 0 min, 5 min, 10 min, 30 min after intervention during surgery and at 8h,24 h after surgery. | At 0 min, 5 min, 10 min, 30 min after intervention during surgery and at 8h,24 h after surgery |