Please assess the completion status of the following clinical trial:

Trial Title: Efficacy Study of Ketamine for Postoperative Pain in Opioid Dependent Patients

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: SINGLE_GROUP
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: QUADRUPLE
- Phase: PHASE4
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~* Chronic pain \> 6 months~* Long term use of opioids~* Major surgery~Exclusion Criteria:~* Use of regional anesthetic techniques~* No need for intravenous (IV) patient controlled analgesia (PCA) after surgery

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: None
- Healthy Volunteers: f

Study Arms:
- Ketamine (Type: ACTIVE_COMPARATOR): Participants received postoperative hydromorphone patient-controlled analgesia (PCA) and continuous ketamine (0.2 mg/kg/hour). Ketamine is being compared to the use of placebo, in addition to intravenous opioids, for postop pain control in opioid dependent patients who undergo major surgery.
- Placebo (Type: PLACEBO_COMPARATOR): Participants received postoperative hydromorphone PCA and continuous ketamine-matching placebo (infusion of saline).

Based on this trial design, predict the completion outcome and termination type (if applicable).