Analgesia Nociception Index (ANI) After Unilateral Radical Mastectomy as an Evaluation of Paravertebral Block Failure

Institut de Cancérologie de Lorraine100 enrolled

Overview

Paravertebral Block (PVB) combined with general anesthesia (GA) is a conventional pain treatment for breast surgery but sometimes failures can occurs. The efficacy of this block has to be evaluated. Also, for the intra-operative analgesic evaluation of this block, it is necessary to measure intra-operative analgesia index. A monitor of nociception for patients under GA, the PhysiodolorisTM device, offers an index for measuring nociceptive inputs during surgery in anesthetized patients : the ANI index (based on the single R-R interval analysis). The purpose of this observational and prospective study is to assess the variations of this ANI index during breast surgery with or without axillary node dissection with a PVB. This will allow us to quantify the analgesic effect of a PVB during GA for unilateral radical breast surgery with or without axillary node dissection.

Study Type

OBSERVATIONAL

Enrollment

100

Conditions

Breast Cancer

Interventions

Analgesia Nociception IndexOTHER

A monitor of nociception for patients under general anesthesia

Medical Language ↔ Plain English

Inclusion Criteria: * American Society of Anesthesiologists score (ASA) I or II * Woman * Patients aged over 18 years * BMI between 17 and 30 kg/m2 * Radical mastectomy with or without axillary node dissection. Exclusion Criteria: * Preoperative consumption of opioid * Local Anesthesia allergy * Local skin inflammation at the puncture area * Inability to respond to pain assessment using a Numerical Rating Score (NRS) * Any contra-indication or patient's refusal for regional anesthesia B blocker medication * Pace maker * Inability to perform the PVB (at the appreciation of the anesthesiologist) * Change of surgical procedure other modified radical mastectomy with or without axillary node dissection. * Patient with a severe side effect or who cannot be controlled by additional therapy will be removed from the trial

Outcomes

Primary Outcomes

Assessment of the ANI index

Assessment of the area under the curve of the variation of the ANI index for the first minute of the surgical incision according to the PVB failure: incomplete or ineffective vs effective. The PVB failure will be evaluate with a cold test on the thoracic levels T2 and T6.

Time frame: first minute of the surgical incision

Secondary Outcomes

Post Anesthesia Care Unit total dose of morphine will be compare according to the PVB failure or not groups.

Time frame: Just after surgery (day 0)

Evaluation of pain

Evaluation of the Numerical Rating Score (NRS) (no pain = 0, worst pain =10): NRS at arrival in the post anesthesia care unit , NRS at leaving of the post anesthesia care unit and at the postoperative day 1. NRS will be compare according to the PVB failure

Time frame: Just after surgery (day 0) and the day after surgery (day 1)