Evaluating the role of Serratus anterior plane block to manage post-thoracotomy pain: a randomized controlled trial, Phase II

investigate the effect of Serratus anterior plane block to manage post-thoracotomy pain

This is a randomized, double-blind clinical trial (phase II) with parallel groups that is performed on 120 patients who are candidate for thoracotomy. Randomization is conducted by using online block randomization software. The severity of post-surgical pain is evaluated by using Visual analog scale (VAS).

This study is conducted in the surgery department of Shariati Hospital in Tehran. All patients receive IV morphine, 5 mg every 6 hours, IV Apotel 1 gr every 8 hours, and Diclofenac suppository every 8 hours for pain control. In addition to these treatments, the intervention group undergoes Serratus anterior plane block before closing the surgical incision, So, the patient is blind about the study group. That researcher who evaluates the outcome, dose not participates in randomization and surgery procedure so is blind about the patient group too.

Patients over 18 years of age candidate for thoracotomy, who met the American Society of Anesthesiology (ASA) Class I-II classification criteria. Participants who has met any of the following criteria were excluded from the study: Participants who refused to cooperate History of sensitivity to local anesthesia Patients with American Society of Anesthesiologists (ASA) class IV-V criteria. Unstable hemodynamic (systolic blood pressure <90 mm-Hg or mean arterial pressure <60 mm-Hg) Coagulation disorders Surgical site infection

Control: control pain with opioids, NSAIDs or acetaminophen Intervention: control pain with opioids, NSAIDs or acetaminophen and, they will undergo Serratus anterior plane block.

Post-thoracotomy pain/ Visual analog scale (VAS) is used to evaluate this outcome in 6, 12 and 24 hours after operation.

In this study randomization performs based on the blocked randomization method. Information such as the number of study groups (2 main groups: intervention (for example A) and control (for example (B), block size (a multiple of the number of groups that will be chosen in this study to reduce the complexity of the work, size 4) and the total number of patients (sample size 60 people), were enter into the online software machines specific for this calculation (for example available at https://www.sealedenvelope.com/simple-randomiser/v1/lists) and according to the codes that it is obtained by the final analysis (including the number of specific groups of 4, which will be 17 groups here) (for example (group B 1, 4, 1, each of the patients being studied is given a specific code respectively. Blocking is usually used in order to create a balance in the number of samples assigned to each of the studied groups. In this method, equal blocking will be used. In this way, the samples are randomized in two groups as much as possible.

All steps of group assignment are done by a researcher who does not have a role in the data collection, and the data will be recorded by a researcher who is blind to the group allocation and was not involved or present during the surgery, and will not know about the sample group until after the data analysis. Patients do not know which group they are in and the intervention is done before the patient regains consciousness.