Patient-controlled intravenous analgesia (PCA) has already proven its quality. However, with new strategies starting to emerge and the current concept of opioid sparing, it is a goal to find the optimal PCA strategy capable of improve patient satisfaction and, at the same time, individualize opioid dose.

In a prospected randomized study, it was compared the use of Sufentanil Sublingual PCA System with intravenous PCA Morphine in terms of postoperative pain control satisfaction, total dose of opioid required, adverse effects, impact on the quality of postoperative recovery and the incidence of postoperative chronic pain.

In a prospected randomized study, it was compared the use of Sufentanil Sublingual PCA System (15mcg per tablet, 20 minutes lockout) with intravenous PCA Morphine based on 1mg morphine on-demand 10 minutes lockout and a baseline perfusion of 1mg/hour.

45 patients capable of comply a PCA regime submitted to total knee arthroplasty, total hip arthroplasty and abdominal hysterectomy were enrolled in the study. During the first 48 hours, it was accessed daily pain scores, PCA use, need for rescue therapy, adverse effects, global satisfaction as well as postoperative quality recovery. Brief Pain Inventory was performed before surgery and 4 months later.

Inclusion Criteria:

• Informed consent signed;
• Age superior to 18 years;
• Physical status according to the American Society of Anesthesiology (ASA) 1-3;
• Scheduled gynecological surgery: abdominal hysterectomy
• Scheduled orthopedic surgery: total knee arthroplasty or total hip arthroplasty.

Exclusion Criteria:

• Patient refusal to participate in the study;
• Age <18 years or legal dependence;
• Neurological or psychiatric pathology or altered state of consciousness that does not allow for the Patient Controlled Analgesia strategy;
• Documented drinking habits and/or consumption of illicit drugs;
• Patients tolerant to opioid therapy (use of >15 mg oral morphine or its equivalent per day for the last 3 months);
• Documented obstructive Sleep Apnea Syndrome (OSAS);
• Patients on long-term oxygen therapy;
• Intraoperative use of intrathecal morphine;
• Use of anesthetic techniques in order to provide postoperative analgesia (eg, epidural catheter; peripheral nerve block; infiltration of the surgical wound with local anesthetic).