High Versus Low Dose Serratus Anterior Plane Block After Minimally Invasive Valve Surgery.
- Conditions
- Cardiac DiseaseSurgeryAnalgesiaPost Operative Pain
- Interventions
- Procedure: Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight)Procedure: High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight)
- Registration Number
- NCT06205875
- Lead Sponsor
- Jessa Hospital
- Brief 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.
- 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.
Recruitment & Eligibility
- Status
- RECRUITING
- Sex
- All
- Target Recruitment
- 100
- 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%
- 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)
- 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,...)
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Intervention group PCIA with morphine Patients in the intervention group will receive a mixture of high-dose local anesthetic and epinephrine administered via a serratus anterior plane block. Control group PCIA with morphine Patients in the control group will receive a serratus anterior plane block with a low dose local anesthetic (based upon our primary trial). Control group Low dose serratus anterior plane block (1.2mg/kg patient ideal body weight) Patients in the control group will receive a serratus anterior plane block with a low dose local anesthetic (based upon our primary trial). Intervention group High dose serratus anterior plane block (2.4 mg/kg patient ideal body weight) Patients in the intervention group will receive a mixture of high-dose local anesthetic and epinephrine administered via a serratus anterior plane block.
- Primary Outcome Measures
Name Time Method Cumulative opioid consumption by patient-controlled intravenous analgesia (PCIA) 24 hours after block placement Morphine consumption will be directly read from the PCIA-system after 24 hours
- Secondary Outcome Measures
Name Time Method Bupivacaine dosage at 30minutes as well as at 1, 2, 4 and 8 hours after block placement 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.
Opioid consumption during predetermined time intervals after surgery Every 4 hours until 24 hours after placement of the SAP block Morphine consumption will be directly read from PCIA-system at predetermined time intervals after performing the SAP block.
Postoperative pain score in rest and on deep respiration 4, 8, 12 and 24 hours after performing the SAP block and at postoperative day 7. 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.
Time to extubation Throughout study completion, an average of 7 days Time from arrival to the ICU until extubation in minutes.
Time to first mobilization Intended at 6 hours after surgery Time from arrival to the ICU until first mobilization.
Postoperative nausea and vomiting (PONV) 24 hours after performing the SAP block at postoperative day 1 The simplified PONV impact scale will be used to asses PONV. Clinically important PONV will be defined as a score of 5 or more.
ICU length of stay Until postoperative day 7 Time from arrival to the ICU until meeting discharge criteria to the ward in postoperative hours.
Hospital length of stay Throughout study completion, an average of 7 days Time to discharge out of the hospital in postoperative days (day of surgery = day 0)
Opioid free patients first 24 postoperative hours First 24 hours Number of patients that do not require any additional opioids within the first 24 hours after block placement.
Overall patient Satisfaction with analgesic therapy 24 hours after performing the SAP block at postoperative day 1. 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)
Constipation Until postoperative day 7 Time to first defecation (postoperative days) or need for laxatives during hospital stay (number of patients)
Pneumonia Until postoperative day 7 Defined as empirical antibiotic therapy for suspicion of pneumonia during hospital stay, in number of patients.
Quality of recovery At postoperative day 2 and 7 Quality of recovery will be assessed with Quality of Life questionnaires: EuroQol\*5D (EQ5D) and short form health survey (SF-36).
Trial Locations
- Locations (1)
Jessa hospital
🇧🇪Hasselt, Limburg, Belgium