Nociception Level Monitor (NOL) During Guided Analgesic Delivery in Breast Surgeries

Influence of Nociception Level Monitor (NOL) During Guided Analgesic Delivery in Breast Surgeries on the Perioperative Course, Quality of Recovery and Hospital Stay

To assess if perioperative consumption of opioids can be optimized with the assistance of a Nociception Level (NOL) monitor in breast surgery patients receiving pectoral and parasternal nerve blocks as supplementation to general anaesthesia.

Hypothesis:

1. NOL monitor guidance optimizes perioperative analgesic consumption and postoperative length of stay and offers a better quality of recovery in breast surgery.
2. Intraoperative NOL monitoring can detect the efficacy of pectoralis and parasternal nerve blocks.
3. Incidence of persistent neuropathic pain after breast cancer surgery is lower in patients receiving lower doses of perioperative opioids.

Optimal perioperative pain management is important not only for patient satisfaction but also for hemodynamic stability and effective restitution. Despite being the principal element of anaesthesia, analgesia delivery has long been based on non-objective surrogate parameters such as blood pressure and heart rate. This may lead to hemodynamic inconsistency, poor restitution and patient dissatisfaction, which are some of the observed challenges. In that context, there has long been a search for a monitor which can guide the meticulous administration of analgesics. Recently, a nociception level monitor (NOL) based on an advanced software algorithm was developed using multiple physiological parameters. It offers an objective number (NOL Index) which relates to the level of intra-operative pain. NOL technology has been validated and found superior to existing pain indicators in peer-reviewed publications. With the availability of NOL monitors, a meticulous adjustment in the administration of opioids became a possibility. Therefore, the investigators are planning a randomised study to investigate if opioid consumption can be reduced and if immediate and long-term postoperative complications can be minimised.

Inclusion Criteria:

• American Society of Anaesthesiologists (ASA) class I-IV patients scheduled for an elective mastectomy with or without axillary resection

Exclusion Criteria:

• Inability to give consent,
• atrial fibrillation,
• local anesthetic allergy,
• lumpectomy converted to Mastectomy.