The effectiveness of the analgesic and anti-nausea prevention techniques of the investigators justifies being evaluated regularly in order to adapt the management strategy to the specificities of each surgical act.

A first evaluation took place in June 2016 and allowed to identify a category of patients (partial breast surgery with or without axillary gesture) not benefiting from an ideal algological management because justifying in 30% of the cases of a level 3 analgesic remedy in the postoperative recovery room. This use of morphine results in a significant incidence of postoperative nausea and prolonged recovery time before return home harmful to the patient.

With their experience in locoregional anesthesia technique in complete breast surgery (total mastectomy) and aware of the effectiveness of this type of anesthesia on the management of immediate and chronic pain, the investigators have extended their indications of ALR to partial breast surgery in ambulatory.

During the anesthesia consultation, the risk of postoperative nausea and vomiting (PONV) is evaluated by the Apfel score (Apfel CC, Anesthesiology 1999) and a preventive strategy correlated to this score is then determined. An order including anti-emetics and analgesics is given to the patient for the return home after the outpatient surgery.

On the day of the outpatient surgery, patients receive in the operating room the prevention of PONV according to their level of risk (according to the recommendations of the Société Française d'Anesthésie et de Réanimation - SFAR 2008 and Guidelines 2014) and analgesics including a level II and NSAIDs (in the absence of contraindication).

All patients underwent general anaesthesia with sufentanil and propofol. Mechanical ventilation was performed with laryngeal mask. A echoguided regional anesthesia was performed by injection of 20 ml of ropivacaine 3.75 mg/ml above and under the serratus muscle as described by Blanco and al (ref 3)" In the postoperative recovery room, PONV is treated if necessary by an anti-emetic class different from those used in the block. In postoperative pain with EVA> 3, morphine titration is performed as recommended.

Patients are then monitored in an outpatient surgery unit until they have a home-based return capability assessed by the CHUNG score, including the level of pain (moderate and well relieved), the absence of persistent nausea, and the ability to ambulation.

All outpatient surgery patients are called the day after their return home to ensure the absence of complications according to the regulatory procedure related to outpatient anesthesia.

As part of this evaluation, information on the level of pain at rest and mobility, as well as the frequency of PONV are also recorded and this follow-up is repeated in D2 and D3 after the intervention.

This information is then correlated with the type of anesthesia performed, the surgical procedure as well as the analgesic strategy (ALR) and the antinausea strategy performed.

Inclusion Criteria:

• patients admitted for ambulatory surgery under general anesthesia
• patients admitted during the period from 01 to 30 June 2016 or during the period from 18 to 5 July 2018

Exclusion Criteria:

• Patient neither French nor English,
• Patient refusing to participate in this study
• Minor patients were excluded to ensure the homogeneity of the surveyed population (satisfaction of minors not meeting the same characteristics as that of adults)

During the period from 01 to 30 June 2016, all patients admitted for ambulatory surgery under general anesthesia were included in this prospective "before-after" study.

To have two perfectly comparable populations, we chose to reassess all patients in outpatient surgery combined, on the second period (18 to 5 July 2018), even if our changes of care only concerns breast.