Please assess the completion status of the following clinical trial:

Trial Title: Perioperative Opioid-induced Hyperalgesia and Its Prevention With Ketamine and Methadone

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: DOUBLE
- Phase: None
- Number of Arms: 4.0

Eligibility Criteria:
Inclusion Criteria:~* patients undergoing open colo-rectal surgery~Exclusion Criteria:~* ASA status more than II, history of chronic pain, ischemic heart disease or chronic pulmonary disease, allergy to any drugs used in the protocol. Body Max Index more than 35.

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 75 Years
- Healthy Volunteers: f

Study Arms:
- zero/morphine (Type: NO_INTERVENTION): Patient received a standard balance anaesthesia and morphine for post operative pain.
- ketamine/morphine (Type: EXPERIMENTAL): Ketamine infusion scheme: 5mcg/Kg/min from induction od anaesthesia for 10 min, than 2,5mcg/Kg/min for 20 min and than 2 mcg/Kg/min to the end of surgery.
- zero/metadone (Type: EXPERIMENTAL): Methadone PCA
- ketamine/methadone (Type: EXPERIMENTAL): Ketamine infusion scheme: 5mcg/Kg/min from induction od anaesthesia for 10 min, than 2,5mcg/Kg/min for 20 min and than 2 mcg/Kg/min to the end of surgery.~Methadone administered by a PCA system (dose 2 mg, lock-out 12min.).

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