Dexmedetomidine in Serratus Plane Block for Mastectomy

Alaa Mazy

Status: Completed

Conditions: Postoperative Pain

Treatments: Drug: Bupivacaine; Drug: General anesthesia; Drug: Bupivacaine-Dexmedetomidine

Study type: Interventional

Funder types: Other

Identifiers

NCT03498092

MD/16.06.08

Details and patient eligibility

About

The serratus plane block (SPB) described by Blanco et al, 2013 is a progression from the work with the Pecs I and II blocks. The serratus muscle is a superficial and easily identified muscle and considered a true landmark to perform thoracic wall blocks because lateral cutaneous branches of the intercostal nerves pierce it in the mid-axillary line. A local anesthetic (LA) is injected under ultrasound (US) guidance either superficial or deep to serratus anterior muscle providing predictable and relatively long-lasting regional anesthesia, which would be suitable for surgical procedures performed on the chest wall.

The linear US probe of frequency (6-13 MHz) is placed over the mid-clavicular region in a sagittal plane.The ribs are counted inferiorly and laterally until the fifth rib in the midaxillary line is identified.The latissimus dorsi, teres major, and serratus muscles are identified.

Full description

Possible regional techniques for breast surgery include selective intercostal nerve blockade, thoracic paravertebral blockade, thoracic epidural, intrapleural, local wound infiltration. Each of these techniques has advantages and disadvantages. In general, local or wound infiltration is safe but limited in terms of duration of action, depending on the local anesthetic (LA) used. More invasive techniques such as selective intercostal nerve blocks and thoracic paravertebral blockade may be complicated by pneumothorax or transient Horner's syndrome These techniques are also may be associated with higher risk of local anesthetic toxicity. Besides the neurological side-effects associated with thoracic epidural and paravertebral blocks such as post-sympathectomy hypotension and bradycardia, total spinal block, paraplegia, epidural hematoma, unpredictable spread, intravascular injection also requires special skill precluding their routine use in the setting of day-case surgery. With the use of ultrasound (US) devices in anesthetic practice, newer regional techniques based on detailed knowledge of innervations of the breast are developed as the pectoral nerve (Pecs) block I and II.The breast innervations briefly include lateral and medial pectoral nerves that arise from the brachial plexus innervating the pectoral muscles.The anterior divisions of the thoracic intercostal nerves from T2 to T6. They give off lateral and anterior branches. The Lateral branches pierce the external intercostalis and the serratus anterior muscles at the mid-axillary line to give off anterior and posterior terminal cutaneous branches. The lateral cutaneous branch of the second intercostal nerve does not divide and it is called the intercostobrachial nerve.The Anterior branches pierce the internal intercostalis muscle, the intercostal membranes, and pectoralis major to supply the breast in its medial aspect.The long thoracic nerve passes on the serratus anterior muscle supplying it. The thoracodorsal nerve innervates the latissimus dorsi muscle.

Enrollment: 150 patients

Sex: Female

Ages: 20 to 60 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Patients of American Society of Anesthesiologists (ASA) grade I - III.
2. Scheduled for unilateral modified radical mastectomy.

Exclusion criteria

1. Patient with the skin infection in the axilla.
2. Allergy to local anesthetics of the amide type.
3. Patient refusal.

Trial design

Primary purpose: Supportive Care

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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150 participants in 3 patient groups, including a placebo group

Bupivacaine-Dexmedetomidine group

Experimental group

Description:

After general anesthesia, patients will receive a cocktail of isobaric bupivacaine 2.5 mg/ml plus 5 micrograms (mcg)/ml adrenaline and 1mcg/kg dexmedetomidine in a volume of 0.5 ml/kg injected superficial to serratus muscle between and below latissimus dorsi muscle.

Treatment:

Drug: Bupivacaine-Dexmedetomidine

Bupivacaine group

Active Comparator group

Description:

After general anesthesia, patients will receive a cocktail of isobaric bupivacaine 2.5 mg/ml plus 5 micrograms (mcg)/ml adrenaline in a volume of 0.5 ml/kg injected superficial to serratus muscle between and below latissimus dorsi muscle.

Treatment:

Drug: Bupivacaine

Saline group

Placebo Comparator group

Description:

This group will serve as a control and blinding group and will receive saline infiltration in the same manner.

Treatment:

Drug: General anesthesia