TAP Block: Does Volume Make a Difference?

Study Overview
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Brief Summary
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Patients who have abdominal surgery will experience pain from the incision. The lumbar TAP block is a procedure used to reach the nerve endings in the abdominal wall so that there is a reduction in pain after surgery. Using ultrasound guidance, a solution of ropivacaine will be injected after surgery. The aim of this study is to determine the effect of changes in the volume of the injection.

Detailed Description
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Pain from a surgical incision happens in most patients. During the perioperative period, the use of the TAP block has been shown to reduce pain scores, opioid consumption and sedation scores. Also, there is a trend towards a reduction of post-operative nausea and vomiting. The aim of the block is to reach the distal nerve endings of the abdominal wall from T6 to L1 dermatomes using ultrasound guidance with a single shot of ropivacaine at different volumes. Currently, there is consensus about optimal procedure-specific volumes and local anesthetic concentrations for lumbar TAP blocks. This is a pilot study and the purpose being is it feasible to do a large scale clinical study to determine the influence of increasing the local anesthetic volume.

Official Title
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Lumbar Transversus Abdominal Plane (TAP) Block: Does Volume Make a Difference?

Conditions
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Post-operative Pain

Intervention / Treatment
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* Drug: Ropivacaine
* Drug: Ropivacaine
* Drug: Ropivacaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18-70 years old total abdominal hysterectomy capable of completing informed consent no previous chronic opioid use no previous abdominal wall surgeries Exclusion Criteria: patient refusal contraindication to regional anesthesia: coagulopathy, anticoagulant use, bleeding disorders, local or systemic infection local anesthetic allergy BMI>35

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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: Supportive Care
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 20mLs of 0.5% ropivacaine per side<br> | Drug: Ropivacaine<br>* 20mLs of 0.5%<br>* Other names: naropin;|
| Experimental: 30mLs of 0.33% ropivacaine per side<br> | Drug: Ropivacaine<br>* 30mLs of 0.33%<br>* Other names: naropin;|
| Experimental: 40mLs of 0.25% ropivacaine per side<br> | Drug: Ropivacaine<br>* 40mLs of 0.25%<br>* Other names: naropin;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To assess the feasibility of a large scale clinical study to determine the influence on increasing the local anesthetic volume. | This will be shown as a number and a percenttage of patients recruited and randomized. | 6 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Using ice and pinprick, determine the dermatomal block distribution at 2,6,12,24 and 48 hours post block. | The assessor will measure the extend of the block distribution at the various time intervals. | 48 hours | 
| Pain scores at 2,6,12,24, and 48 hours post-block. | Using a visual analog scale, patient pain scores will be assessed. | 48 hours | 
| Patient-controlled analgesia opioid requirements at 2,6,12,24 and 48 post-block. | Record drug consumption at the time intervals | 48 hours | 
| Incidence of post-operative nausea and vomiting at 2,6,12,24, and 48 hours. |  | 48 hours | 
| Block failure rate. | Block failure rate is defined as the lack of any sensory block following the TAP block. | 48 hours | 
| Patient's overall satisfaction. | Using a LIKERT score, patient satisfaction will be measured. | 48 hours | 
| Discharge time from PACU. | The time in which the patient is discharged from the recovery room. | 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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TAP block, incision pain, total hysterectomy