Programmed Intermittent Bolus Infusion of Thoracic Paravertebral Block for Hepatectomy

Study Overview
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Brief Summary
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Hepatectomy induces moderate to severe postoperative pain. Patient-controlled intravenous analgesia has been used in many medical centers for post-hepatectomy analgesia, but the effects are limited and often cause undesirable adverse effects. Regional Block has been used for postoperative analgesia in many surgeries. Some studies suggest that regional analgesia has an opioid-sparing effect and can reduce the incidence of chronic pain. Also, the programmed intermittent bolus infusion is better than continuous infusion, with less analgesic consumption and fewer adverse effects. Studies on the early and late postoperative analgesia and recovery effects of paravertebral block for open hepatectomy are scarce. Therefore, the investigators aim to conduct a prospective, randomized, subject and assessor-blinded, parallel-group, placebo-controlled study to test the hypothesis that the programmed intermittent bolus infusion of right thoracic paravertebral block reduces postoperative intravenous analgesic use and pain scores and improved patients' satisfaction.

Detailed Description
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This study aims to compare the early postoperative morphine consumptions, pain scores, rescue analgesics, adverse effects and recovery indices, and the late postoperative life quality between patients with and without paravertebral block.

Official Title
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Early and Late Postoperative Analgesia and Recovery Effects of Programmed Intermittent Bolus Infusion of Thoracic Paravertebral Block for Hepatectomy: A Prospective, Randomized, Double-blinded, Controlled Study

Conditions
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Paravertebral Block, Hepatectomy, Analgesia, Postoperative Recovery

Intervention / Treatment
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* Procedure: Paravertebral block-ropivacaine
* Procedure: Paravertebral block-saline
* Drug: patient controlled analgesia with morphine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-70 yrs American Society of Anesthesiologists physical statusⅠ-Ⅲ Undergo hepatectomy with J-shape subcostal incision Informed consent Exclusion Criteria: A known allergy to the drugs being used Coagulopathy, on anticoagulants Analgesics intake, history of substance abuse Participating in the investigation of another experimental agent Unable to cooperate, eg. inability to properly describe postoperative pain to investigators

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: PTPVB-ropivacaine<br>Programmed intermittent bolus infusion of a thoracic paravertebral block with ropivacaine and patient-controlled analgesia with morphine | Procedure: Paravertebral block-ropivacaine<br>* Inject 25 ml 0.5% ropivacaine in the T8 paravertebral space followed with catheter insertion and continuous 0.2% ropivacaine infusion(infusion rate: 0.125ml/kg/pulse,1pulse/h)<br>* Other names: PVB group;Drug: patient controlled analgesia with morphine<br>* Morphine was given as intravenous patient-controlled analgesia bolus: 1-2mg, lock time: 5min, 1h limitation: 8mg<br>* Other names: PCIA;|
| Placebo Comparator: PTPVB-saline<br>Programmed intermittent bolus infusion of a thoracic paravertebral block with saline and patient-controlled analgesia with morphine | Procedure: Paravertebral block-saline<br>* Inject 25 ml 0.9% saline in the T8 paravertebral space followed with catheter insertion and continuous 0.9% saline infusion(infusion rate: 0.125ml/kg/pulse,1pulse/h)<br>* Other names: Control group;Drug: patient controlled analgesia with morphine<br>* Morphine was given as intravenous patient-controlled analgesia bolus: 1-2mg, lock time: 5min, 1h limitation: 8mg<br>* Other names: PCIA;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative 48hrs morphine | Cumulate morphine consumption 48 hours after hepatectomy | Postoperative 48 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart rate | The average value of the heart rate during the operation measured at 10 minutes interval | During the operation | 
| Mean blood pressure | The average value of the mean blood pressure (=1/3 systolic pressure + 2/3 diastolic pressure) during the operation measured at 10 minutes interval. | During the operation | 
| Sevoflurane concentration | The average value of the sevoflurane concentration during the operation measured at 10 minutes interval | During the operation | 
| Intraoperative medication dose | Doses of fentanyl, ephedrine, atrophin, phylepherine and urapidil used during the operation | During the operation | 
| Fluid volumes | Fluid volumes including volumes of crystalloid, colloid, red blood cells, plasma, platelet, Urine and hemorrhage. | During the operation | 
| Awake and extubation time | Time from stop of sevoflurane use to patient awake and extubation. | At the end of the operation | 
| Postoperative morphine consumption | Cumulative morphine consumption at 2, 4, 12, 24 hours after hepatectomy | Postoperative 2, 4, 12, 24hours | 
| Operation time | Time from the start to the end of the operation | During the operation | 
| The pain scores(at rest and with cough) determined by the numeric rating scale | NRS is an internationally recognized pain scale with 11 points ranging from 0 to 10 points, with 0 defined as no pain and 10 defined as the worst pain imaginable. | Postoperative 0, 2, 4, 12, 24 and 48 hours | 
| Adverse effects | Adverse effects of morphine including nausea, vomiting, pruritus and respiratory depression, bowel movement and Foley catheter removal. | Postoperative 0-48 hours | 
| Rescue analgesia | Times of rescue analgesia | Postoperative 0-48hours | 
| Postoperative recovery indices | Postoperative recovery indices including drowsiness, thirsty, cold feeling, cognitive decline and shiver evaluated using a 0-3 points Likert scale, with 0 defined as none, 1 defined as mild, 2 defined as moderate and 3 defined as severe. | Postoperative 48 hours | 
| Satisfaction indices | Emergence, analgesia and overall satisfaction evaluated using a 1-5 points Likert scale, with 1 defined as very unsatisfied, 2 defined as unsatisfied, 3 defined as no comments, 4 defined as satisfied and 5 defined as very satisfied. | Postoperative 48 hours | 
| Length of hospital stay | Number of in-hospital days from admission to discharge | Two weeks after hospital discharge | 
| Chronic recovery data | Chronic recovery data including incidence of pain, numbness, hypoesthesia and sleep disorder | Postoperative 3 months | 
| Chronic pain characteristics | Incidence of difference types of pain including throbbing, aching, pricking and stabbing. | Postoperative 3 months | 
| Chronic pain NRS score | NRS is an internationally recognised pain scale with 11 points ranging from 0 to 10 points, with 0 defined as no pain and 10 defined as the worst pain imaginable. | Postoperative 3 months |