Serratus Anterior Plane Block for Minimal Invasive Cardiac Surgery

Study Overview
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Brief Summary
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Analgesia in cardiac surgery is historically based on large doses of intravenous opiods. However, this practice is rapidly changing due to Enhanced Recovery After Surgery (ERAS) protocols with proven benefits on morbidity and mortality. Also, the opioid crisis caused by opioid abuse, has changed anaesthesia practice to reduce the use of opioids after surgery. Therefore, perioperative multimodal pain management with regional anaesthesia in minimal invasive cardiac surgery (MICS) has gained a lot of interest. Serratus Anterior Plane Block (SAPB) is one example of the fascial plane chest wall blocks and aims at achieving complete sensory loss of the anterolateral hemithorax via blockade of the lateral cutaneous branches of the thoracic intercostal nerves (T2-T12). SAPB has already proved its efficacy in thoracic surgery as it reduced pain scores and opioid consumption compared to systemic analgesia in the first 12-24h after surgery. However only few studies investigated the effects of SAPB in minimal invasive cardiac surgery. Therefore the primary aim of this study is to investigate the analgesic effects of a superficial SAPB in Minimal Invasive Cardiac Surgery compared to a control group with standard intravenous opioid analgesia.

Detailed Description
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2 x 40 patients scheduled for mitral valve surgery via port access, aortic valve replacement via right anterior thoracotomy and minimal invasice direct coronary artery bypass (MIDCAB) surgery will be randomized in a control or SAPB group. Every patient will receive the standard anaesthetic treatment. At the end of the surgery, patients in the SAPB group will receive levobupivacaine 0.25 %, 2.5 mg/ml (dosage scheme: 1.25 mg/kg levobupivacaine 0.25%, with a maximum of 100 mg). Levobupivacaine will be given via ultrasound-guided infiltration, in plane, midaxillary, 4-5th rib, between the latissimus dorsi and serratus anterior muscle, at the end of the surgery. For both the SAPB group and the control group, the ICU nurse will repeatedly administer piritramide 2 mg intravenously, till numerical rating scale (NRS) are less than 4. Also paracetamol 1 g will be continoued 4 times daily.

Official Title
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Serratus Anterior Plane Block for Minimal Invasive Cardiac Surgery: a Single Center Randomized-controlled Trial

Conditions
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Minimal Invasive Cardiac Surgery, Mitral Valve Surgery, Aortic Valve Replacement, Minimal Invasive Direct Coronary Artery Bypass

Intervention / Treatment
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* Drug: Levobupivacaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Patients scheduled for mitral valve surgery via port access, aortic valve replacement via right anterior thoracotomy and minimal invase direct coronary artery bypass Exclusion Criteria: Patients who are pregnant or breastfeeding BMI >35 Opioid abuse Patients known with chronic pain Patients known with allergy to local anaesthetics (in this case levobupivacaine) Patients known with hypersensitivity to piritramide Patients who receive medication that could possibly interact with levobupivacaine (sa. mexilatine, ketoconazol, theophylline) Patients who simultaneously participate in another interventional clinical trial, unless the Principal Investigators of the clinical trials give consent by mutual agreement that the patient can participate in another interventional clinical trial Soft tissue infection in the area of the procedure

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: SAPB<br>The IMP is levobupivacaine 0,25%, 2,5 mg/ml, solution for injection. The dosage scheme is as following:1.25 mg/kg levobupivacaine 0,25%, with a maximum of 100 mg, As the standard anaesthetic management already contains levobupivacaine, a maximum dosage of 100 mg (40 ml) levobupivacaine will be administered during the SAPB. The IMP is given via ultrasound-guided infiltration, in plane, midaxillary, 4-5th rib, between the latissimus dorsi and serratus anterior muscle, at the end of surgery. | Drug: Levobupivacaine<br>* The IMP is levobupivacaine 0,25%, 2,5 mg/ml, solution for injection. The dosage scheme is as following:1.25 mg/kg levobupivacaine 0,25%, with a maximum of 100 mg, As the standard anaesthetic management already contains levobupivacaine, a maximum dosage of 100 mg (40 ml) levobupivacaine will be administered during the SAPB. The IMP is given via ultrasound-guided infiltration, in plane, midaxillary, 4-5th rib, between the latissimus dorsi and serratus anterior muscle, at the end of surgery.<br>|
| No Intervention: Control<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Analgesic effect of superficial SAPB in MICS | Numeric (pain) Rating Scale every 2 hours | In the first 48 hours after surgery | 
| Analgesic effect of superficial SAPB in MICS | Total opioid consumption in the intensive care unit | In the first 48 hours after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of postoperative nausea and vomiting | PONV every 2 hours | In the first 48 hours after surgery | 
| Time to extubation in the intensive care unit |  | From arrival on the ICU until discharge on the ICU | 
| ICU length of stay |  | From arrival on the ICU until discharge on the ICU | 
| PaCO2 | PaCO2 every 4 hours, calculated by an arterial blood gas test | In the first 48 hours after surgery |