TAP Block Efficacy After Lumbar Spine Surgery Through Anterior Approach: a Randomized, Placebo-controlled Study

Study Overview
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Brief Summary
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Anterior Lumbar Interbody Fusion (ALIF) as well as Direct Lateral Interbody Fusion (DLIF) are established techniques for lumbar interbody fusion. In contrast with posterior approaches, they allow free approach to the anterior disc space without opening of the spinal canal or the neural foramina. However, the additional anterior approach conveys specific concerns, including abdominal pain that may delay recovery after surgery. The transversus abdominis plane (TAP) block is a validated approach for postoperative pain relief following abdominal surgeries. There is currently no evidence of the possible benefits of TAP block as part of multimodal pain management after ALIF/DLIF surgery. The investigator hypothesize that a single-injection TAP block reduces opioid consumption after anterior lumbar fusion surgery. The main goal of this prospective, randomized, double-blind, placebo-controlled study is to demonstrate a >35% reduction in opioid consumption during the 24h following ALIF/DLIF surgery.

Detailed Description
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Clinical trial : therapeutic, prospective, randomized,double blind, placebo-controlled, with parallel group, of superiority, in intention to treat, monocentric study. The main steps of the study are: preoperative assessment of eligibility exclusion and inclusion criteria, written informed consent, baseline preoperative assessment (see specific section) randomization (using a computer generated list) immediately before induction of anesthesia TAP block: ropivacaine + clonidine (experimental group, n=20) OR saline (control group; n=20) anesthesia (propofol, sufentanil, cisatracurium, ketamine and desflurane) and postoperative analgesia (paracetamol, ketoprofen, nefopam, and patient-controlled analgesia with morphine) similar in both groups surgical procedure primary outcome parameter (morphine consumption first 24 hours; see specific section) secondary endpoints (see specific section, up to 6 months following surgery)

Official Title
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Analgesic Efficacy of Transversus Abdominis Plane (TAP) Block After Lumbar Spine Surgery Through Anterior Approach (Anterior Lumbar or Direct Lateral Interbody Fusion): a Prospective, Randomized, Double-blind Placebo-controlled Study

Conditions
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Pain, Postoperative

Intervention / Treatment
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* Drug: ropivacaine plus clonidine
* Drug: Placebo
* Device: ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Man or woman over the age of 18 yr Patients with insurance coverage Patients able to provide free and informed consent Patients undergoing surgery by the ALIF or DLIF approaches Exclusion Criteria: Patients receiving opioids as chronic treatment Patients with contra-indication to regional anesthesia or TAP block Patients unable to consent Patient refusal Patients with contra-indication to any drug included in the anesthesia or analgesia protocol Pregnancy or breast-feeding women

Ages Eligible for Study
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Minimum Age: 18 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: TAP block with ropivacaine<br>Bilateral single shot TAP block under ultrasound guidance: 20 mL ropivacaine 3.75 mg/ml + 75 µg clonidine, per side | Drug: ropivacaine plus clonidine<br>* 20 mL ropivacaine 3.75 mg/ml + 75 µg clonidine, per side<br>Device: ultrasound<br> <br> |
| Placebo Comparator: TAP block with placebo<br>Placebo administration: bilateral single shot TAP block under ultrasound guidance: 20 mL saline 0.9%, per side | Drug: Placebo<br>* 20 mL saline 0.9%, per side<br>Device: ultrasound<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Morphine consumption | patient-controlled administration | During the first 24 postoperative hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| intraoperative sufentanil consumption | infusion adjusted according to heart rate and arterial pressure | At the end of anesthesia | 
| Sedation scale | using WHO Sedation scale - 0 = awake and alert /- 1 = quietly awake / - 2 = asleep but easily roused / - 3 = deep sleep | During the first 6 hours | 
| Morphine consumption | patient-controlled administration | between the 24 and the 48 postoperative hours | 
| Postoperative nausea and vomiting (PONV) Score | Measure the presence and severity of postoperative nausea and vomiting the PONV score :- 1 = mild /- 2 = moderate / - 3 = severe | first 24 postoperative hours | 
| Antiemetics consumption |  | During the first 24 postoperative hours | 
| resumption of intestinal transit |  | Up to the end of hospital stay | 
| visual analog scale | Measure the pain severity | At Baseline, at wake up, during the first 48 postoperative hours, At 3 and 6 months after surgery | 
| Area peri-incisional hyperalgesia | von frey's hair | At 48 hours | 
| Questionnaire Douleur de Saint-Antoine (QDSA) , | evaluation with validated scores for chronic and neuropathic pains | At Baseline, At 3 and 6 months after surgery | 
| Questionnaire d'Evaluation des Douleurs Neuropathiques (QEDN), | evaluation with validated scores for chronic and neuropathic pains | At Baseline, At 3 and 6 months after surgery | 
| Sullivan's pain catastrophising scale, | evaluation with validated scores for chronic and neuropathic pains | At Baseline, At 3 and 6 months after surgery | 
| Hospital Anxiety and Depression Scale (HAD scale), | evaluation with validated scores for chronic and neuropathic pains | At Baseline, At 3 and 6 months after surgery | 
| Oswestry score | evaluation with validated scores for chronic and neuropathic pains | At Baseline, At 3 and 6 months after surgery |