Effects of Dexmedetomidine Used in Continuous Thoracic Paravertebral Blocks

Weifeng Tu

Status and phase: Completed; Phase 4

Conditions: Post-thoracotomy Pain Syndrome

Treatments: Device: Mindray M7 series; Drug: Ropivacaine; Drug: Dexmedetomidine

Study type: Interventional

Funder types: Other

Identifiers

NCT02619513

Dexmedetomidine TPVB

Details and patient eligibility

About

The purpose of this study is to explore the effectiveness of dexmedetomidine as an adjunctive analgesic, used in ultrasound-guided continuous thoracic paravertebral blocks for Post-thoracotomy Pain Syndrome(PTPS).

Full description

Thoracic surgical procedures are among the most painful operations, and their outcomes are affected adversely by postoperative discomfort. Post-thoracotomy pain syndrome (PTPS) is a well-recognized complication of thoracotomy. Post-thoracotomy pain control improves patient satisfaction and decreases postoperative complication morbidity. Epidural analgesia used to be considered as the best method of pain relief after major surgery despite its side-effects, which includes hypotension, respiratory depression, incomplete or failed block, etc. Recently, paravertebral block is an alternative technique that may offer a comparable analgesic effect and a better side-effect profile for post-thoracotomy pain. Dexmedetomidine(DEX) is a Food and Drug Administration-approved, parenteral, selective α2-agonist that induces anxiolytic and analgesia without respiratory depression. It could provide dose-dependent sedation , analgesia , anti-anxiety and inhibition of sympathetic nerves and other effects . Current studies with regard to the effectiveness of DEX as an adjunctive medicine, used in ultrasound-guided continuous thoracic paravertebral blocks for PTPS. The mechanical withdrawal threshold and VAS scores are recorded. The consumption of opioid and general anesthetics during perioperative period are also recorded. To compare the incidence rates of side effects, such as nausea, vomiting, dizziness, hypotension and bradyarrhythmia in the first 3 days after operation among the groups.Also,to measure and compare the level of inflammatory factor in different group.A questionnaire is adopted to investigate whether there are chronic pain symptoms happen at 6 months after the operation which aim to PTPS.

Enrollment: 60 patients

Sex: All

Ages: 19 to 76 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. ASA Ⅰ～Ⅲ patient undergoing thoracotomy;
2. Written informed consent from the patient or the relatives of the participating patient.
3. BMI:18～25kg/m2

Exclusion criteria

1. Mental illness;
2. Epidural anesthesia or thoracic paravertebral blocks contraindicated;
3. People who have Slow-type arrhythmias or hypotension;
4. People who have lung infection or sleep apnea syndrome;
5. People who have chronic renal failure;
6. Alcohol or drug abuse;
7. Already taking gabapentin, pregabalin, benzodiazepin or antidepression drug;
8. Local anesthetics allergy;

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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60 participants in 4 patient groups

General anesthesia group(Group GA)

No Intervention group

Description:

Group GA received general anesthesia only and intravenous analgesia pump.

TEB group(Group GE)

Experimental group

Description:

Group GE received continuous thoracic epidural block(TEB) combined with general anesthesia and postoperative continuous thoracic epidural analgesia, and only added ropivacaine in PVB as an postoperative adjuvant.

Treatment:

Drug: Ropivacaine

PVB without DEX group (Group GT)

Experimental group

Description:

Group GT received ultrasound-guided(Mindray M7 series) continuous thoracic paravertebral nerve block(PVB) combined with general anesthesia and continuous thoracic paravertebral nerve block patient-controlled analgesia, and only added ropivacaine in PVB as an postoperative adjuvant.

Treatment:

Device: Mindray M7 series

Drug: Ropivacaine

PVB with DEX group(Group GTD)

Experimental group

Description:

Group GTD received ultrasound-guided(Mindray M7 series) continuous thoracic paravertebral nerve block combined with general anesthesia and continuous thoracic paravertebral nerve block patient-controlled analgesia,but with dexmedetomidine 0.5μg/kg added to ropivacaine in PVB as an adjuvant.

Treatment:

Drug: Dexmedetomidine

Device: Mindray M7 series

Drug: Ropivacaine