Biradar PA, Kaimar P, Gopalakrishna K Effect of dexamethasone added to lidocaine in supraclavicular brachial plexus block: A prospective, randomised, double-blind study. Indian J Anaesth. 2013 Mar;57(2):180-4. doi: 10.4103/0019-5049.111850.
Shrestha BR, Maharjan SK, Tabedar S Supraclavicular brachial plexus block with and without dexamethasone - a comparative study. Kathmandu Univ Med J (KUMJ). 2003 Jul-Sep;1(3):158-60.
Tandoc MN, Fan L, Kolesnikov S, Kruglov A, Nader ND Adjuvant dexamethasone with bupivacaine prolongs the duration of interscalene block: a prospective randomized trial. J Anesth. 2011 Oct;25(5):704-9. doi: 10.1007/s00540-011-1180-x.
Yadav RK, Sah BP, Kumar P, Singh SN Effectiveness of addition of neostigmine or dexamethasone to local anaesthetic in providing perioperative analgesia for brachial plexus block: A prospective, randomized, double blinded, controlled study. Kathmandu Univ
Yaghoobi S, Seddighi M, Yazdi Z, Ghafouri R, Khezri MB Comparison of Postoperative Analgesic Effect of Dexamethasone and Fentanyl Added to Lidocaine through Axillary Block in Forearm Fracture. Pain Res Treat. 2013;2013:761583. doi: 10.1155/2013/761583.
A Randomized Comparison Between Intravenous and Perineural Dexamethasone for Ultrasound-Guided Axillary Blocks
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.