Safety and Clinical Utility Study of SSEC Fentanyl 40 mcg for Acute Post-op Pain Management in Pediatric Participants

Inclusion Criteria: * Participants whose parent(s) or guardian(s) have/has signed and dated an informed consent form for the participant to participate in the study, or participants who have provided written assent to participate in the study * Male or female inpatients, age 12 to \<18 years of age inclusive on the day of surgery * Participants capable of understanding and cooperating with the requirements of the study, including being able to report their pain intensity using the 11-point Numeric Rating Scale and operate the SSEC * American Society of Anesthesiologists physical status I, II or III * Body weight of at least 40.0 kilogram (kg) * Postoperative participants who have undergone general or regional anesthesia for abdominal, pelvic/genitourinary, orthopedic, or thoracic surgery * Postoperative participants who have been observed during recovery and are expected to remain hospitalized and have pain requiring parenteral opioids (that is, intravenous \[IV\] patient-controlled anesthesia) for the next 24 hours or longer * Participants who are awake and breathing spontaneously with a respiratory rate of 14 to 18 breaths per minute, peripheral capillary oxygen saturation ≥93% (with or without supplemental oxygen), and able to answer questions and follow commands * Participants who have been observed during recovery, who are awake, able to answer questions and follow commands, and who have been comfortable for at least 30 minutes, with a pain intensity score ≤4 (numeric rating scale 0-10), with or without titration to comfort with IV opioids Exclusion Criteria: * Participants who have undergone any surgery on the airway, head, or neck * Participants who received an extended-release opioid within 48 hours prior to Hour 0 or who are expected to have postoperative analgesia supplied by a continuous regional technique or participant-controlled epidural analgesia * Participants with a history of allergy or hypersensitivity to fentanyl, skin adhesives, and/or cetylpyridinium chloride * Participants who are expected to require intensive care or will likely require additional surgical procedures within 36 hours * Participants who received intra-operative and/or postoperative administration of opioids other than morphine, hydromorphone, fentanyl, sufentanil, or alfentanil. Exception: If there are no medical contraindications, meperidine (pethidine) up to 0.5 milligram/kg IV is permitted during recovery for shivering * Participants who require airway support (nasal or oropharyngeal airway intubation, or laryngeal mask airway at the time of final baseline assessments (that is, at the time of IONSYS application \[Hour 0\]) * Participants who are known or suspected to be opioid tolerant, have a history of opioid dependence within 3 months before the start of the study, or who are known to have used illicit drugs or alcohol within 14 days of the start of the study * Participants with active generalized skin disorders or active local skin disease that precludes SSEC application to the chest or upper arm * Participants with any coexisting major medical conditions that are likely to interfere with study procedures including, but not limited to, psychiatric conditions, chronic depression, suicidal ideation, autism * Positive pregnancy test for any female