Is PECS Block Equivalent to Paravertebral Block in Preventing Postoperative Pain After Breast Surgery? A Randomized, Controlled, Double-blind, Multicenter Trial

Aim of the study is to compare paravertebral block and PECS block success rate in patients undergoing elective breast surgery (mastectomy or quadrantectomy) with a combined anesthesia technique.

Primary outcome is block success rate defined as a VAS score of 30 or less in PACU and at 6, 12 and 24 hours after surgery. Secondary outcomes are: rescue opioids requirement; incidence of procedure related complications; incidence of postoperative side-effects; patients' quality of life level during the first 24 postoperative hours; patients' satisfaction.

A prospective, randomized, controlled, double-blinded, non-inferiority trial was designed in order to compare paravertebral block and PECS block with regard to block success over the first 24 hours postoperatively in patients undergoing mastectomy or quadrantectomy procedures with a combined anesthesia technique.

Inclusion criteria: adult patients, ASA class 1 to 3, scheduled for elective mastectomy or quadrantectomy. Exclusion criteria: patients refusal, contraindication to regional anaesthesia (coagulopathies, concurrent anticoagulant therapy, allergy to local anaesthetics, infection at puncture site).

After written informed consent, patients will be randomized into two cohorts, the first being treated with a paravertebral block, while the second with a PECS block. Both procedures will be standardized with regard to injection technique, local anaesthetic drug and volume and performed under ultrasound real-time guidance. Both groups will undergo the regional anesthesia technique after induction of general anaesthesia to be blinded with regard to the type of block. This will be standardized as well, according to our centers current clinical practice. Postoperative pain will be than measured on a validated visual analogue scale (VAS 0-100) in the recovery room and periodically after discharge to the ward until 24 hours postoperatively. Rescue opioids requirement will be recorded. Eventual procedural complications occurred will be recorded as well as postoperative side effects. A questionnaire about patients' satisfaction and quality of life during the first 24 postoperative hours will be filled in for every patient. Data collected will be initially inserted in a form and subsequently collected, pooled and anonymously registered in an electronic data base.