Effectiveness of TAP (Transversus Abdominis Plane) Block for Abdominal Aortic Surgery

Study Overview
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Brief Summary
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The goal of this study is to learn about the effectiveness of TAP block for pain relief after vascular surgery on the abdominal aorta. The main question the investigators are looking to answer is whether the TAP block lowers the dose of opioid required after abdominal aortic surgery.

Detailed Description
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The surgery on the abdominal aorta requires extended haemodynamic monitoring and is performed under general anaesthesia. After applying general anaesthesia, the patients will receive a TAP block (subcostal approach) before the start of the surgery. During the procedure the patients will receive both opioid and nonopioid analgesics, as part of the standard perioperative protocol for abdominal aortic surgery. After the procedure all patients will receive following the standard protocol for pain relief after abdominal aortic surgery - NSAIDs and nonopioid analgesics regularly. All patients will postoperatively receive opioid as a rescue drug as needed (PCA). Participants will be randomly allocated in two groups, where one group will receive local anaesthetic for the TAP block and the control group will receive normal saline for the TAP block. The anaesthetist, the nurses and doctors in the postoperative care will all be blinded as to the group in which each patient is allocated. The participants will be followed from surgery until discharge from hospital.

Official Title
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Effectiveness of TAP (Transversus Abdominis Plane) Block for Postoperative Pain Relief After Abdominal Aortic Surgery

Conditions
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Abdominal Aortic Aneurysm, Abdominal Aortic Stenosis, Syndrome, Leriche

Intervention / Treatment
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* Other: ropivacaine
* Other: normal saline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients admitted for an elective vascular surgery on abdominal aorta that agree and give written consent to be included in the study. Exclusion Criteria: Patients allergic to the drugs we will use in the study, local anaesthetic, nonopioid analgesics, NSAIDs. Patients with pain syndromes that are preoperatively already on any kind of chronic pain therapy. Patients that will experience surgical complications that requires reoperation will be excluded postoperatively.

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 |
| --- | --- |
| Active Comparator: ropivacaine<br>Participants in this group will receive TAP block with 0,75%, bilaterally. | Other: ropivacaine<br>* single shot bilateral TAP block<br>|
| Placebo Comparator: normal saline<br>Participants in this group will receive TAP block with normal saline, bilaterally. | Other: normal saline<br>* single shot bilateral TAP block<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cumulative dose of opioid in the first 48 hours after surgery | Cumulative dose of opioid, administered in the first 48 hours after surgery | 48 hours after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Length of hospital stay | Length of hospital stay after surgery measured in days | up to 2 weeks | 
| Patient satisfaction with pain relief | The participants will be asked to grade their satisfaction of pain relief on a 5 rating satisfaction scale from 1 - 5 (where 1 is best and 5 is worst). 1.very satisfied 2.satisfied 3. neither satisfied nor dissatisfied 4.dissatisfied 5. very dissatisfied | up to 7 days postoperatively | 
| Return of peristalsis | Return of peristalsis after surgery measured in days | up to 2 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Abdominal aorta, TAP