AnalgesiaNCT06205875
High Versus Low Dose Serratus Anterior Plane Block After Minimally Invasive Valve Surgery.
A study testing High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight), Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight) and PCIA with morphine in people with Analgesia and Surgery, run by Jessa Hospital at 1 site in Belgium.
Trial summary
This study aims to compare the efficacy and quality of pain relief provided by the high-dose serratus anterior plane (SAP) block with the standard SAP block in preventing and treating acute postoperative pain after total endoscopic aortic or mitral valve surgery. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Analgesia, Surgery, Cardiac Disease
- What is being tested?
- High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight), Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight) and PCIA with morphine
- Type of treatment
- Injection or infusion, Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 100 participants
- Where
- 1 siteBelgium
- Study dates
- 21 Feb 2024to 31 Dec 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Scheduled for elective aortic valve surgery or elective mitral valve surgery via right anterolateral thoracotomy
- Adult patients (minimally 18 years old)
- Bodyweight > 50kg
- EuroScore ii < 3%
Who cannot join
- Refusal to participate
- Inability to communicate due to language or neurologic barriers
- Inability to control and self-administer opioids with PCIA or to comprehend the NRS pain score due to confusion or learning difficulties
- Chronic use of opioids
- Chronic use of analgesic antidepressants and/or antiepileptics
- Use of prohibited medication which possibly interacts with bupivacaine-epinephrine or opioids (mexiletine, ketoconazole, theophylline, IMAO, Digitalis and cimetidine)
Show all 13Show fewer
- History of major trauma or surgery to right chest wall
- History of chronic pain at right chest wall
- Allergy to opioids and/or local anesthetics
- Allergy to paracetamol
- Class 3 obesity (BMI 40 or more)
- Pregnancy
- Intraoperative events compromising early postoperative recovery (aortic dissection, systolic anterior motion of the mitral valve, cardiac tamponade, brady-arrhytmias requiring external pacing,...)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Belgium1 site, 1 recruiting
- Recruiting
Jessa hospital
Hasselt, Limburg, 3500
Björn Stessel, Dr., 003211339856, bjorn.stessel@jessazh.be
Ina Callebaut, PhD, 003211339848, ina.callebaut@jessazh.be
About this study
Official title: High Versus Low Dose Serratus Anterior Plane Block After Minimally Invasive Valve Surgery: a Double-blinded Randomized Controlled Trial.
This study aims to compare the efficacy and quality of pain relief provided by the high-dose serratus anterior plane (SAP) block with the standard SAP block in preventing and treating acute postoperative pain after total endoscopic aortic or mitral valve surgery.
Read the detailed description
During the last two decades, cardiac surgical techniques have changed dramatically. Evidence for good short and long-term outcomes after endovascular and minimally invasive procedures is rising. This shift made it possible to avoid sternotomy and thus facilitating earlier patient recovery without compromising safety. Therefore, enhanced recovery after surgery (ERAS) protocols have been implemented to aim for early extubation and ambulation. While policies for early extubation and discharge from the hospital have been implemented, the analgesic regimen has not been modified. Opioids remain the standard treatment in the postoperative setting after cardiac surgery despite known side effects such as nausea, constipation and the risk of addiction. Neuraxial anaesthesia techniques, which require fewer opioids in cardiac surgery, have been studied and validated but not yet implemented.
In 2013, the serratus anterior plane (SAP) block was described as a pain relief option for chest surgery. This anaesthesia technique injects local anaesthetics under the serratus muscle and between the latissimus dorsi and serratus anterior using ultrasound. Successful pain relief with this SAP block has been reported in thoracotomy, chest surgery, and rib fractures. In our previous study, we demonstrated a 40% reduction in morphine consumption during the first 24 hours after total endoscopic aortic valve replacement with an SAP block compared to a control group without an SAP block. Lower pain scores were also observed in the SAP group
As such, in this proposed study, we aim to optimise the intensity of the Serratus anterior plane block (SAPB) to decrease opioid requirements further and to encounter more favourable secondary clinical outcome parameters. One strategy to increase the duration of action of plane blocks is injecting higher doses of local anaesthetics. A meta-analysis by De Oliveira et al. on transabdominal plane (TAP)-blocks for abdominal surgery showed a correlation between the local anaesthetic dose and the late block effect, impacting both pain scores and opioid consumption. In a randomised controlled trial by Suresh, a TAP block with bupivacaine 1.25 mcg/kg was compared to a TAP block with bupivacaine 2.5 mcg/kg, revealing a longer duration of analgesia and a lower need for additional analgesics up to 24 hours post-surgery. Moreover, loading doses up to 2mg/kg body weight are recommended for truncal blocks in general, but the mean injected dose in our intervention group was 1.25mg/kg, considering a mean patient body weight of 79.2kg. Notably, a pharmacokinetic study by Maximos and colleagues on an adrenalised bupivacaine mixture after pectointercostal fascial plane block (PIFB) after cardiac surgery showed that, despite injecting 2mcg/kg adrenalised bupivacain, both total and free arterial serum bupivacaine levels were 10-20 times lower than levels associated with neurologic or cardiovascular toxicity in the literature.
In conclusion, we are convinced we can safely improve the late effects of our SAPB compared to our first study by increasing the dose of the local anesthetic injectate.
- Conditions
- Analgesia, Surgery, Cardiac Disease, Post Operative Pain
- Being tested
- High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight), Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight), PCIA with morphine
- Keywords
- Aorta/mitral valve surgery, Serratus anterior plane block, Enhanced recovery after surgery, post operative pain
- Medical subject headings
- Agnosia, Heart Diseases, Pain, Postoperative
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight)Procedure or surgery
The needle will be introduced in-plane from supero-anterior to postero-inferior until the needle tip is positioned in the plane underneath the serratus muscle (deep compartment). Under continuous ultrasound guidance, 3/4th of the bupivacaine 0.25% plus epinephrine solution will be injected in the deep compartment. After the deep component of the serratus anterior plane block is completed, the needle will be withdrawn to the subcutaneous tissues. The needle will be flattened and advanced in-plane to the plane superficial to the serratus muscles. The remainder quarter of the bupivacaine 0.25% plus epinephrine solution will be injected superficial to the serratus muscles after correct placement of the needle tip is confirmed on ultrasound. In total a dose of 2.4mg/kg patient ideal body weight will be administered. There is a maximal dose of 200 mg adrenalized bupivacaine for patients with an ideal body weight of 83 kg or more.
Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight)Procedure or surgery
The needle will be introduced in-plane from supero-anterior to postero-inferior until the needle tip is positioned in the plane underneath the serratus muscle (deep compartment). Under continuous ultrasound guidance, 3/4th of the bupivacaine 0.25% will be injected in the deep compartment. After the deep component of the serratus anterior plane block is completed, the needle will be withdrawn to the subcutaneous tissues. The needle will be flattened and advanced in-plane to the plane superficial to the serratus muscles. The remainder quarter of the bupivacaine 0.25% will be injected superficial to the serratus muscles after correct placement of the needle tip is confirmed on ultrasound.
PCIA with morphineDrug
Also called PCIA with Sterop
A patient controlled intravenous analgesia system (Bodyguard 595 Colorvision®) with morphine (Sterop®) using following settings: bolus 1.5 mg and lockout interval 7 min with maximal dose of 30mg per 4 hours.
| Study group | Role | What they receive |
|---|---|---|
| Intervention group | Experimental | Patients in the intervention group will receive a mixture of high-dose local anesthetic and epinephrine administered via a serratus anterior plane block. Receives: Procedure: High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight); Drug: PCIA with morphine |
| Control group | Active comparator | Patients in the control group will receive a serratus anterior plane block with a low dose local anesthetic (based upon our primary trial). Receives: Procedure: Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight); Drug: PCIA with morphine |
What is being measured
The primary outcome is the main question the study is designed to answer.
Cumulative opioid consumption by patient-controlled intravenous analgesia (PCIA)
Morphine consumption will be directly read from the PCIA-system after 24 hours
Measured: 24 hours after block placement
Secondary outcomes (13)
Opioid consumption during predetermined time intervals after surgery
Morphine consumption will be directly read from PCIA-system at predetermined time intervals after performing the SAP block.
Measured: Every 4 hours until 24 hours after placement of the SAP block
Opioid free patients first 24 postoperative hours
Number of patients that do not require any additional opioids within the first 24 hours after block placement.
Measured: First 24 hours
Postoperative pain score in rest and on deep respiration
The postoperative pain in rest, as well as with deep respiration on the surgical site, is evaluated based on an 11-point numeric scale (NRS) where 0 = no pain and 10 = worst pain ever.
Measured: 4, 8, 12 and 24 hours after performing the SAP block and at postoperative day 7.
Overall patient Satisfaction with analgesic therapy
Overall patient satisfaction with analgesic therapy will be assessed with an 11-point NRS scale (where 0 = not satisfied at all and 10 = extremely satisfied)
Measured: 24 hours after performing the SAP block at postoperative day 1.
Time to extubation
Time from arrival to the ICU until extubation in minutes.
Measured: Throughout study completion, an average of 7 days
Time to first mobilization
Time from arrival to the ICU until first mobilization.
Measured: Intended at 6 hours after surgery
Postoperative nausea and vomiting (PONV)
The simplified PONV impact scale will be used to asses PONV. Clinically important PONV will be defined as a score of 5 or more.
Measured: 24 hours after performing the SAP block at postoperative day 1
Constipation
Time to first defecation (postoperative days) or need for laxatives during hospital stay (number of patients)
Measured: Until postoperative day 7
ICU length of stay
Time from arrival to the ICU until meeting discharge criteria to the ward in postoperative hours.
Measured: Until postoperative day 7
Hospital length of stay
Time to discharge out of the hospital in postoperative days (day of surgery = day 0)
Measured: Throughout study completion, an average of 7 days
Pneumonia
Defined as empirical antibiotic therapy for suspicion of pneumonia during hospital stay, in number of patients.
Measured: Until postoperative day 7
Quality of recovery
Quality of recovery will be assessed with Quality of Life questionnaires: EuroQol*5D (EQ5D) and short form health survey (SF-36).
Measured: At postoperative day 2 and 7
Bupivacaine dosage
In the first 36 study patients, arterial blood samples will be taken to calculate the dosage of total and free plasma bupivacaine levels. For each patient 5 samples will be collected, with a total amount of 50 ml blood per patient.
Measured: at 30minutes as well as at 1, 2, 4 and 8 hours after block placement
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Jan 2024
- Study start21 Feb 2024
- Primary completion31 Dec 2027 (estimated)
- Study completion31 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for AnalgesiaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- This trial is designed as a mono-center, double-blinded, prospective, randomized controlled superiority trail comparing 2 groups of patients
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Jessa Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Stessel Björn, Jessa Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06205875
- Sponsor's protocol ID
- f/2023/119
- Status last verified
- May 2025
- First submitted
- 4 Jan 2024
- Last updated
- 14 May 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 14 May 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- High Versus Low Dose Serratus Anterior Plane Block After Minimally Invasive Valve Surgery: a Double-blinded Randomized Controlled Trial.
- ClinicalTrials.gov ID
- NCT06205875
- Acronym / sponsor ID
- f/2023/119
- Conditions
- Analgesia, Surgery, Cardiac Disease, Post Operative Pain
- Keywords
- Aorta/mitral valve surgery, Serratus anterior plane block, Enhanced recovery after surgery, post operative pain
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Jessa HospitalUniversity, hospital or other
- Study start
- 21 Feb 2024 (actual)
- Primary completion
- 31 Dec 2027 (estimated)
- Study completion
- 31 Dec 2027 (estimated)
- First posted
- 16 Jan 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to compare the efficacy and quality of pain relief provided by the high-dose serratus anterior plane (SAP) block with the standard SAP block in preventing and treating acute postoperative pain after total endoscopic aortic or mitral valve surgery.
Detailed description
During the last two decades, cardiac surgical techniques have changed dramatically. Evidence for good short and long-term outcomes after endovascular and minimally invasive procedures is rising. This shift made it possible to avoid sternotomy and thus facilitating earlier patient recovery without compromising safety. Therefore, enhanced recovery after surgery (ERAS) protocols have been implemented to aim for early extubation and ambulation. While policies for early extubation and discharge from the hospital have been implemented, the analgesic regimen has not been modified. Opioids remain the standard treatment in the postoperative setting after cardiac surgery despite known side effects such as nausea, constipation and the risk of addiction. Neuraxial anaesthesia techniques, which require fewer opioids in cardiac surgery, have been studied and validated but not yet implemented.
In 2013, the serratus anterior plane (SAP) block was described as a pain relief option for chest surgery. This anaesthesia technique injects local anaesthetics under the serratus muscle and between the latissimus dorsi and serratus anterior using ultrasound. Successful pain relief with this SAP block has been reported in thoracotomy, chest surgery, and rib fractures. In our previous study, we demonstrated a 40% reduction in morphine consumption during the first 24 hours after total endoscopic aortic valve replacement with an SAP block compared to a control group without an SAP block. Lower pain scores were also observed in the SAP group
As such, in this proposed study, we aim to optimise the intensity of the Serratus anterior plane block (SAPB) to decrease opioid requirements further and to encounter more favourable secondary clinical outcome parameters. One strategy to increase the duration of action of plane blocks is injecting higher doses of local anaesthetics. A meta-analysis by De Oliveira et al. on transabdominal plane (TAP)-blocks for abdominal surgery showed a correlation between the local anaesthetic dose and the late block effect, impacting both pain scores and opioid consumption. In a randomised controlled trial by Suresh, a TAP block with bupivacaine 1.25 mcg/kg was compared to a TAP block with bupivacaine 2.5 mcg/kg, revealing a longer duration of analgesia and a lower need for additional analgesics up to 24 hours post-surgery. Moreover, loading doses up to 2mg/kg body weight are recommended for truncal blocks in general, but the mean injected dose in our intervention group was 1.25mg/kg, considering a mean patient body weight of 79.2kg. Notably, a pharmacokinetic study by Maximos and colleagues on an adrenalised bupivacaine mixture after pectointercostal fascial plane block (PIFB) after cardiac surgery showed that, despite injecting 2mcg/kg adrenalised bupivacain, both total and free arterial serum bupivacaine levels were 10-20 times lower than levels associated with neurologic or cardiovascular toxicity in the literature.
In conclusion, we are convinced we can safely improve the late effects of our SAPB compared to our first study by increasing the dose of the local anesthetic injectate.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- This trial is designed as a mono-center, double-blinded, prospective, randomized controlled superiority trail comparing 2 groups of patients
| Arm | Type | Receives |
|---|---|---|
| Intervention group | Experimental | Procedure: High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight), Drug: PCIA with morphinePatients in the intervention group will receive a mixture of high-dose local anesthetic and epinephrine administered via a serratus anterior plane block. |
| Control group | Active comparator | Procedure: Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight), Drug: PCIA with morphinePatients in the control group will receive a serratus anterior plane block with a low dose local anesthetic (based upon our primary trial). |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Scheduled for elective aortic valve surgery or elective mitral valve surgery via right anterolateral thoracotomy
- Adult patients (minimally 18 years old)
- Bodyweight > 50kg
- EuroScore ii < 3%
Key exclusion criteria (13 listed)
- Refusal to participate
- Inability to communicate due to language or neurologic barriers
- Inability to control and self-administer opioids with PCIA or to comprehend the NRS pain score due to confusion or learning difficulties
- Chronic use of opioids
- Chronic use of analgesic antidepressants and/or antiepileptics
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight)The needle will be introduced in-plane from supero-anterior to postero-inferior until the needle tip is positioned in the plane underneath the serratus muscle (deep compartment). Under continuous ultrasound guidance, 3/4th of the bupivacaine 0.25% plus epinephrine solution will be injected in the deep compartment. After the deep component of the serratus anterior plane block is completed, the needle will be withdrawn to the subcutaneous tissues. The needle will be flattened and advanced in-plane to the plane superficial to the serratus muscles. The remainder quarter of the bupivacaine 0.25% plus epinephrine solution will be injected superficial to the serratus muscles after correct placement of the needle tip is confirmed on ultrasound. In total a dose of 2.4mg/kg patient ideal body weight will be administered. There is a maximal dose of 200 mg adrenalized bupivacaine for patients with an ideal body weight of 83 kg or more. | Procedure or surgery | Intervention group |
| Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight)The needle will be introduced in-plane from supero-anterior to postero-inferior until the needle tip is positioned in the plane underneath the serratus muscle (deep compartment). Under continuous ultrasound guidance, 3/4th of the bupivacaine 0.25% will be injected in the deep compartment. After the deep component of the serratus anterior plane block is completed, the needle will be withdrawn to the subcutaneous tissues. The needle will be flattened and advanced in-plane to the plane superficial to the serratus muscles. The remainder quarter of the bupivacaine 0.25% will be injected superficial to the serratus muscles after correct placement of the needle tip is confirmed on ultrasound. | Procedure or surgery | Control group |
| PCIA with morphineAlso: PCIA with SteropA patient controlled intravenous analgesia system (Bodyguard 595 Colorvision®) with morphine (Sterop®) using following settings: bolus 1.5 mg and lockout interval 7 min with maximal dose of 30mg per 4 hours. | Drug | Control group, Intervention group |
Primary outcome
Cumulative opioid consumption by patient-controlled intravenous analgesia (PCIA)
Time frame: 24 hours after block placement
Morphine consumption will be directly read from the PCIA-system after 24 hours
13 secondary outcomes
Opioid consumption during predetermined time intervals after surgery
Time frame: Every 4 hours until 24 hours after placement of the SAP block
Opioid free patients first 24 postoperative hours
Time frame: First 24 hours
Postoperative pain score in rest and on deep respiration
Time frame: 4, 8, 12 and 24 hours after performing the SAP block and at postoperative day 7.
Overall patient Satisfaction with analgesic therapy
Time frame: 24 hours after performing the SAP block at postoperative day 1.
Time to extubation
Time frame: Throughout study completion, an average of 7 days
Time to first mobilization
Time frame: Intended at 6 hours after surgery
Postoperative nausea and vomiting (PONV)
Time frame: 24 hours after performing the SAP block at postoperative day 1
Constipation
Time frame: Until postoperative day 7
ICU length of stay
Time frame: Until postoperative day 7
Hospital length of stay
Time frame: Throughout study completion, an average of 7 days
Pneumonia
Time frame: Until postoperative day 7
Quality of recovery
Time frame: At postoperative day 2 and 7
Bupivacaine dosage
Time frame: at 30minutes as well as at 1, 2, 4 and 8 hours after block placement
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 May 2025.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight), Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight) and PCIA with morphine in people with Analgesia and Surgery, run by Jessa Hospital at 1 site in Belgium.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 13 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 14 May 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Belgium. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Björn Stessel, Dr (003211222107, bjorn.stessel@jessazh.be), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Cumulative opioid consumption by patient-controlled intravenous analgesia (PCIA) (time frame: 24 hours after block placement). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 May 2025.