Postoperative Opioid Consumption of Serratus Posterior Superior Intercostal Plane Block Versus Thoracic Paravertebral Block

Postoperative Opioid Consumption of Serratus Posterior Superior Intercostal Plane Block Versus Thoracic Paravertebral Block After Open Thoracotomy: A Randomized Prospective Trial

Previous studies found that paravertebral and thoracic epidural continuous infusions of opioid-free local anaesthetic were found to be comparable, but paravertebral analgesia (PVA) was associated with less respiratory complications and hypotension. The newly emerging Serratus posterior superior intercostal plane block (SPSIPB) provided excellent analgesia in most studies that have focused on video-assissted thoracoscopic surgery (VATS) and breast surgery. The aim of this clinical trial is to achieve better high quality pain control with less opioid consumption either by Serratus Posterior Superior Intercostal Plane Block (SPSIPB) or Thoracic Paravertebral Block after Open thoracotomy. This study will assess and compare the analgesic efficacy of both blocks to reduce opioid consumption, the efficacy of both blocks on postoperative respiratory functions after open thoracotomy. The main question it aims to answer is:

Is there a difference between Serratus Posterior Superior Intercostal Plane Block (SPSIPB) and Thoracic Paravertebral block following open thoracotomy as regard postoperative opioid consumption, postoperative pain score, and postoperative respiratory functions? All patients will take a single dose of local anesthesia either through serratus posterior superior intercostal plane block (SPSIPB) or thoracic paravertebral block and the end of open thoracotomy then total opiod consumption willbe recorded after 24 hours postoperatively.

Study Overview

• Status: Active, not recruiting
• Conditions: Opioid Consumption, Postoperative
• Intervention / Treatment: Procedure: Serratus Posterior Superior Intercostal Plane Block (single injection); Procedure: Thoracic Paravertebral block (single injection)

Detailed Description

Prospective double-blind randomized clinical trial. All patients will be randomly allocated into two equal groups:

Group S (Serratus Posterior Superior Intercostal Plane Block group) Group P (Paravertebral Block group) Using computer generated randomization table, each group consists of 24 patients.

• All patients will be hospitalized and visited a day before the surgery, full history with physical examination and routine investigation will be done, the nature and complications of the study will be explained in detail to the patient and informed written consent will be obtained from all patients.
• Age, sex, body mass index (BMI), and ASA data will be recorded. All patients in both groups will be informed about the numerical rating scale (NRS) for post-operative pain assessment prior to surgery. The NRS is a numerical scale ranging from 0 to 10, where 0-2 mean no pain, 3 mean mild pain, 4-7 mean moderate pain, 8 mean severe pain, and 9-10 mean unbearable pain.11 Also respiratory function will be assessed using spirometry and the forced expiratory volume in 1st second (FEV1).
• All patients will be kept nil orally 8 hours before the operation except for clear fluid 2-3 hours preoperative.
• In the operating room, standard monitors including non-invasive blood pressure (NIBP), digital pulse oximetry and electrocardiogram (ECG) will be connected to the patients, 18 G venous cannula will be inserted with ringer lactate infusion 10 ml/kg/h, also arterial cannula will be inserted for invasive blood pressure monitoring. Capnogram and temperature probe will be applied to each patient and central venous catheter will be inserted after induction of anesthesia.
• All patients will be premedicated with 0.03mg/kg midazolam. General anesthesia will be induced by 2 µg/kg fentanyl, 1.5 mg/kg propofol and 0.6 mg/kg rocuronium will be injected i.v to facilitate tracheal intubation with a left double-lumen endotracheal tube (35-37 French) for one lung ventilation. Patients will be connected to the operating room ventilator immediately after intubation with FIO2 =1, tidal volume =6-8 ml/kg and respiratory rate to maintain Etco2= 35-40mmHg. Anesthesia will be maintained with opioid (fentanyl 1µg/kg/hr), neuromuscular blocking agent (rocuronium 0.6 mg/kg in repeated boluses), and isoflurane (minimum alveolar concentration 1-1.5).
• At the end of the surgery, all patints will take 1 g paracetamol i.v infusion followed by 30 mg/kg ketolac i.v. Also, all patients will take 8 mg ondansteron i.v to prevent postoperative nausea and vomiting (PONV). After that, both groups will undergo regional blocks following the surgical closure and before the reversal of residual neuromuscular blockade in the lateral decubitus with the operative side up and the skin will be prepared with 10% povidone-iodine.

• The blocks will be performed by the same anesthesiologist (performer) who is experienced by at least 20 successful uncomplicated blocks before. The post-operative assessment will be performed by a blinded second anesthesiologist (evaluator). The patient and the evaluator will be blinded to the performed block. The performer anesthesiologist may know the patients included in the block group due to the nature of the study. Both blocks will be performed by a high-frequency (7-12 MHz) linear ultrasound probe, using in-plane technique, 80 mm block needle, and 30 ml of 0.25% bupivacaine for injection.

  1. All patients will be turned into the supine position, and then neuromuscular reversal (with 4mg/kg sugammadex i.v.) and extubation will be performed in the supine position. Patients will be transferred to the recovery room and they will be assessed for pain site and pain score (NRS) at rest and during coughing. Need for analgesia will be defined as NRS ≥ 3 when 0.1 mg/kg i.v. morphine will be given as a rescue analgesia and that will be beside regular i.v. 1 g paracetamol every 8 hours from the initial intraoperative dose for all patients (as a standard analgesia with maximum dose 4 g/ 24 h). The rescue analgesic morphine dose may be repeated 10 minutes later if the pain score is still ≥ 3 with caution for avoidance of sedation or respiratory depression. The NRS will be recorded at 2, 4, 6, 12, 18, 24 hours postoperative while the patient resting (NRS static) and coughing (NRS dynamic). The 1st time for rescue analgesia, the total first 24 hours opioid consumption and its side effects such as nausea, vomiting and pruritus will be recorded. Also respiratory functions (FEV1) will be re-assessed using spirometry and recorded at the same NRS timing in the in-hospital period, and patient satisfaction at 24 hours postoperative by five-point Likert scale.

• Study Type: Interventional
• Enrollment (Estimated): 48
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Egypt
  • Sharqia Province
    • Zagazig, Sharqia Province, Egypt
      • Zagazig university hospitals

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• BMI (25-35kg/m²).
• Physical status: ASA I-II - III.
• Patients undergoing posterolateral thoracotomy for lung resection.

Exclusion Criteria:

• Emergency surgeries.
• Uncooperative patient.
• History of allergy to study drugs.
• Patients with coagulation disorders, advanced hepatic, renal, cardiovascular, respiratory disease and neuropsychiatric disorders (e.g. Alzheimer, Dementia, Delirium, mental retardation and cognitive dysfunction).
• Infection at the site of block .

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Group S (Serratus Posterior Superior Intercostal Plane Block group); patients will receive ultrasound-guided serratus posterior superior intercostal plane block	Procedure: Serratus Posterior Superior Intercostal Plane Block (single injection); As described by Tulger et al., the block will be performed by a high-frequency (7-12 MHz) linear ultrasound probe. After slight scapular lateral displacement, the probe will be placed transversely at the level of the scapular spine. The upper border of the scapula, trapezius muscle, serratus posterior superior muscle (SPSM), and 2nd and 3rd ribs will be visualized. Using in-plane technique, the 80 mm block needle will be introduced from the level of the 3rd rib in the caudocranial direction through the medial scapular border passes through the skin and subcutaneous tissue to target the 3rd rib. After negative aspiration, the needle tip will be placed between the 3rd rib and the SPSM, hydro-dissection using 1-2 ml saline to ensure the correct needle placement then 30 ml of 0.25% bupivacaine will be injected between the SPSM and the 3rd rib.
Active Comparator: Group P (Paravertebral Block group); patients will receive ultrasound guided thoracic paravertebral nerve block	Procedure: Thoracic Paravertebral block (single injection); A high-frequency (7-12 MHz) linear ultrasound probe will be placed 2-3cm lateral to the upper edge of the spinous process of the 5th thoracic vertebrae body which identified by counting down from the seventh cervical vertebrae. After visualizing the transverse process, the underlying muscles, the paravertebral space, the internal intercostal membrane, and the pleura, 80 mm block needle will be inroduced by the in-plane technique till the paravertebral space over the superior border of the transverse process. After identification of the paravertebral space using a loss of resistance technique, 30 ml of 0.25% bupivacaine will be injected.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total opioid consumption	Total first 24 hours opioid consumption	up to 24 hours postoperative

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time of the block performance	time from ultrasound probe placement on patient's skin till the local anesthetic injection	perioperative
1st time for rescue analgesia	time from patient's recovery till numerical rating scale (NRS) ≥ 3	perioperative
Postoperative pain score	The numerical rating scale (NRS) for post-operative pain assessment prior to surgery. The NRS is a numerical scale ranging from 0 to 10, where 0-2 mean no pain, 3 mean mild pain, 4-7 mean moderate pain, 8 mean severe pain, and 9-10 mean unbearable pain.	2 hours, 4 hours, 6 hours, 12 hours, 18 hours, 24 hours postoperative
Forced expiratory volume in 1 second (FEV1)	measuring the maximum amount of air patient can exhale in one second	baseline, 2 hours, 4 hours, 6 hours, 12, hours, 18 hours, 24 hours postoperative
Patient satisfaction	Patient satisfaction at 24 hours postoperative by five-point Likert scale (1 = very dissatisfied, 2 = dissatisfied, 3 = neutral, 4 = satisfied, and 5 = very satisfied	24 hours postoperative

Collaborators and Investigators

• Sponsor: Zagazig University

Study record dates

Study Major Dates

• Study Start (Actual): May 15, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 15, 2026

Study Registration Dates

• First Submitted: May 22, 2026
• First Submitted That Met QC Criteria: May 28, 2026
• First Posted (Actual): May 29, 2026

Study Record Updates

• Last Update Posted (Actual): May 29, 2026
• Last Update Submitted That Met QC Criteria: May 28, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Thoracic Paravertebral Block; Serratus Posterior Superior Intercostal Plane Block; Open Thoracotomy
• Additional Relevant MeSH Terms: Therapeutics; Drug Administration Routes; Drug Therapy; Injections
• Other Study ID Numbers: ZU-IRB # 2312

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No