Pectoralis and Serratus Nerve Blocks for Mastectomy: a Prospective, Randomized, Single-blind Trial

Study Overview
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Brief Summary
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Pectoral nerve block provides a good alternative to epidural or paravertebral block with a lower risk for the patient and that is shown as an optimal anesthetic option with reduction in postoperative pain, anesthetic and opioid consumption. The main objective of this study is to evaluate the quality of the perioperative analgesia of the PECS block in patients electively escalated for the accomplishment of mastectomy under general anesthesia.

Detailed Description
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The advent of ultrasound made possible greater safety and the creation of new peripheral blocks that aim to reduce the morbidity of the anesthetic technique on the cancer patient. Pectoral nerve block (PEC Block) is technically simple and easily reproducible. Inspired by the infraclavicular approach, it aims at the anesthesia of the pectoral, intercostobrachial, intercostal III-IV-V-VI nerves and the long thoracic nerve 8 being a safe, reproducible technique with little discomfort for the patients, with few complications and allowing a good control of acute pain. The hypothesis is that the realization of pectoral nerve block provides a good alternative to epidural or paravertebral block with a lower risk for the patient and that is shown as an optimal anesthetic option with reduction in postoperative pain, anesthetic and opioid consumption. Main objective is the evaluation of postoperative pain through opioid consumption in the first 24 hours postoperatively. Patients will undergo a prospective, randomized, single blind, placebo controlled study in which the examiners responsible for the postoperative evaluation will not know which of the two groups were randomly assigned: 40 patients in the Control and 40 patients in the PECS Group . Patients will be randomized through a list generated by www.randomizer.org into two groups. Patients will receive standard monitoring, pre-anesthetic medication with midazolam 0.05 mg / kg EV. All patients will receive balanced general anesthesia with fentanyl 2 mcg / kg, lidocaine 2 mg / kg, propofol 1-2 mg / kg, cisatracurium 0.15 mg / kg or Rocuronium 0.6 mg / kg. The PECS II group will receive an injection of 20mL of 0.5% Ropivacaine between the serratus and the smaller pectoralis and 10mL of 0.5% ropivacaine between the pectoralis major and minor muscles with the aid of ultrasonography. Maintenance of anesthesia in the two groups: general anesthesia balanced with sevoflurane (with and fraction expired from 1 to 3%, to maintain BIS between 40 and 60). Prophylaxis for postoperative nausea and vomiting will be performed with slow intravenous administration following the anesthetic induction of Dexamethasone 4 mg, and at the end of the surgery slow intravenous administration of Ondansetron 4 mg. At the end of surgery, patients in both groups will receive Dipyrone 2 g and Parecoxib 40 mg. Patients will be evaluated in the postoperative times: T1: arrival at the PACU, T2: 3 hours postoperatively or discharge from the PACU), T3: 12 hours postoperative, T4: 24 hours postoperative.

Official Title
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Pectoralis and Serratus Nerve Blocks for Mastectomy: a Prospective, Randomized, Single-blind, Controlled Trial

Conditions
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Postoperative Pain

Intervention / Treatment
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* Drug: sevoflurane and fentanil
* Drug: sevoflurane and fentanil plus PECS II block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female patients, aged 18 to 60 years, electively scheduled to perform mastectomy in the Base Hospital of the Federal District; Physical State 1, 2 or 3 the American Society of Anesthesiology (ASA); Exclusion Criteria: Patients with unstable angina Patient with poorly controlled asthma Substance abuse Heart failure, greater than first degree atrioventricular block Pregnant women Patients with allergy to dipyrone, morphine; Patients with chronic pain; Patients with severe hepatic disease; Patients with severe kidney disease; Patients with neurological diseases; Included patients in other clinical studies currently or in the past three months under general anesthesia; Patients who refuse to participate in the study; Any other condition that, in the opinion of the investigator, may pose a risk to the patient or interfere with the study objectives;

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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Female

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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo group<br>Patients in placebo group will receive general balanced inhaled anesthesia with sevoflurane and fentanil | Drug: sevoflurane and fentanil<br>* Patients will receive standard general anesthesia<br>* Other names: Standard general anesthesia;|
| Active Comparator: PECS II group<br>Patients in PECS II group will receive general balanced inhaled anesthesia with sevoflurane and fentanil | Drug: sevoflurane and fentanil plus PECS II block<br>* Pacients will receive standard general anesthesia with sevoflurane and fentanil associated to PECS II block<br>* Other names: Standard general anesthesia plus PECS II block;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain Scores on the Visual Analogue Scale | Quantify pain by Visual Analogue Scale (VAS, ranging from 0 to 10 cm, zero being found when the patient is no pain and ten, with maximum or un bearable pain | Within the first 24 hours after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Mastectomy, (PECs) pectoral block