Please assess the completion status of the following clinical trial:

Trial Title: Intravenous Dexamethasone to Increase the Analgesic Duration of Interscalene Block

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: QUADRUPLE
- Phase: None
- Number of Arms: 3.0

Eligibility Criteria:
Inclusion Criteria:~* Elective shoulder arthroscopy under ropivacaine single-shot interscalene brachial plexus block anesthesia (rotator cuff repair and shoulder decompression)~* ASA I-III~* Age 18-80 years old~Exclusion Criteria:~* Any contraindication to interscalene brachial plexus block anesthesia~* Interscalene brachial plexus block failure~* Known local anesthetics allergy~* Dexamethasone allergy or intolerance~* Any contraindication to acetaminophen~* Any contraindication to morphine or hydromorphone~* Brachial plexus neuropathies~* Chronic pain syndrome other than shoulder pain~* Routine use of opioid medication~* Routine use of systemic corticosteroid~* Pregnancy~* Weight below 50 kilograms~* Incapability to understand a numeric verbal pain scale~* Incapability to consent~* Patient refusal

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 80 Years
- Healthy Volunteers: f

Study Arms:
- Dexamethasone 10 mg intravenous (Type: EXPERIMENTAL): Dexamethasone 10 mg diluted with Normal Saline 17,5 mL i.v. (20 mL total) injected slowly during 30 seconds immediately after performing interscalene brachial plexus block
- Dexamethasone 4 mg intravenous (Type: EXPERIMENTAL): Dexamethasone 4 mg diluted with Normal Saline 19 mL i.v. (20 mL total) injected slowly during 30 seconds, immediately after performing interscalene brachial plexus block
- Normal Saline 20 mL intravenous (Type: PLACEBO_COMPARATOR): Normal saline 20 mL injected slowly during 30 seconds, immediately after performing interscalene brachial plexus block

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