The Impact of Pecs Blocks on Postmastectomy Pain Syndrome

Breast cancer is the commonest type of malignancy in women. Chronic postoperative neuropathic pain may appear either in the early postoperative period or at a later stage, usually 3-6 months post-operatively. Chronic post-operative pain syndrome of any magnitude usually involves 19-57% of patients that have undergone any kind of surgical procedure, while 5% of them experience intense symptoms. Risk factors for developing post-mastectomy pain syndrome include younger age, increased Body mass Index (BMI), psychological profile, co-existence of other painful conditions, pre-operative radiotherapy/chemotherapy, type of surgical procedure and anaesthesia, persistent acute postoperative pain, etc. Consequently, chronic post mastectomy pain syndrome results in significant psychosomatic sequelae with variable social impacts for the female patients.

The aim of the present study will be to investigate the incidence of chronic pain following breast cancer surgery in Cyprus, discover its associated risk factors and explore the impact of Pecs Blocks on the appearance of post mastectomy chronic pain symptoms.

During the preoperative visit, the women will be informed about the study and will be instructed to the use of the pain numeric rating scale (NRS) graded from 0 to 10. Standardized anesthesia will be administered. All patients will receive 1000 mg of paracetamol and 0.07 mg/ Kg of morphine intraoperatively. In the Post-Anesthesia Care Unit (PACU), patients will receive additional morphine boluses on request, until NRS score is lesser or equal than 4. Postoperative nausea and vomiting will be treated with ondansetron 4 mg iv. After discharge from PACU, patients will receive a combination of paracetamol 1 gr/6h and im pethidine 75 mg on request, as per hospital protocol.

Numerical rating scores (NRS) at rest and movement will be measured at 6h, 12h and 24h postoperatively. Additionally, the time to first request for analgesia after surgery will be noted.

All patients will also be evaluated 3 and 6 months after surgery with the use of NRS at rest and movement and additionally, via the use of Douleur Neuropathique (DN4) questionnaire for the occurence of neuropathic pain.

Inclusion criteria

• American Society of Anesthesiologists (ASA) I-III patients
• Breast cancer patients
• Patients who receive operative treatment

Exclusion criteria

• inability to consent to the study due to language barriers or cognitive dysfunction -
• skin infection at the puncture site
• contraindication to paracetamol administration
• known previous hepatic or renal impairment as assessed by the patients' history and routine biochemical markers