Optimal Timing of Parasternal Intercostal Nerve Block Application for Acute Pain Management in Cardiac Surgery

Study Overview
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Brief Summary
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Patients experiencing pain after undergoing cardiac surgery may also experience prolonged immobilization, insufficient respiratory functions, and the inability to cough due to median sternotomy. Therefore, duration of mechanical ventilation, length of intensive care unit (ICU) stay, and length of hospital stay of these patients will increase significantly. many facial plane blocks have been introduced as simple and safe intervention for thoracic wall anesthesia and analgesia. Parasternal intercostal nerve block (PSIB) is a superficial block which involves local anesthetic (LA) infiltration in the intercostal space around the sternum where the anterior branches of intercostal nerves exist. Intraoperative LA administration under direct vision of the surgeon ensures adequate delivery of drugs and minimizes bleeding complication or inadvertent administration in blood vessels. Meanwhile, Preoperative administration of LA guided by ultrasound imaging has been used in variable surgical settings with noticeable success because of preemptive inhibition of noxious stimuli.

Official Title
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Optimal Timing of Parasternal Intercostal Nerve Block Application (Pre-incisional Versus Post-incisional) for Acute Pain Management in Cardiac Surgery; a Randomized Double Blinded Clinical Trial

Conditions
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Pain, Acute

Intervention / Treatment
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* Procedure: pre-incisional parasternal intercostal block
* Procedure: post-incisional parasternal intercostal block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age from 20-70 years, Scheduled to undergo elective cardiac surgeries through median sternotomy involving cardiopulmonary bypass (CPB). Exclusion Criteria: Patients requiring preoperative inotropes, mechanical ventilation or intra-aortic balloon pump, patients who have previous cardiac surgery, prolonged CPB time (CPB>120 minutes), Intubation time more than 12hrs or planned for overnight ventilation. Allergy to any of used drugs, opioids addiction, Chronic liver disease, chronic renal disease, and cognitive impairment.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 70 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: Pre-incisional parasternal block<br>ultrasound guided parasternal intercostal block will be administrated before surgical incision. | Procedure: pre-incisional parasternal intercostal block<br>* LA will be administrated by the anesthesiologist under ultrasound guidance and before surgical incision On either side of thorax, 2 cm lateral to sternal edge from 2nd to 6th intercostal space, A volume of (4 mL) of 0.25% bupivacaine will be used<br>|
| Active Comparator: Post-incisional parasternal block<br>under direct vision parasternal intercostal block will be administrated after surgical incision and before closure of the sternum. | Procedure: post-incisional parasternal intercostal block<br>* LA will be administered by the cardiac surgeon before the sternal closure. injection will introduced 2 cm lateral to sternal edge from 2nd to 6th intercostal space and volume (4 mL) of 0.25% bupivacaine will be used.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Amount of rescue analgesia | Total amount of opioid administered as rescue analgesia postoperative. | 24 hours postoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraoperative total fentanyl requirements | the amount of consumed opioid during the procedure | during surgery | 
| intraoperative mean arterial blood pressure (MAP) | hemodynamic variability due to surgical stimulation | during surgery (baseline, at skin incision, at sternotomy, at sternal retraction) | 
| pain score (VAS) | VAS scores will be recorded by making a handwritten mark on a 10-cm line that represented a continuum between no pain and worst possible pain. | at extubation, 12th, 16th, 20th, and 24th hour postoperative | 
| adverse effects | nausea, vomiting, excessive sedation, respiratory depression | 24 hours postoperative | 
| patient satisfaction | 0 extremely unsatisfied to 10 extremely satisfied | 28 hours postoperative | 
| Intensive Care Unit (ICU) Length of Stay |  | up to 6 months |