Casati A, Spreafico E, Putzu M, Fanelli G New technology for noninvasive brain monitoring: continuous cerebral oximetry. Minerva Anestesiol. 2006 Jul-Aug;72(7-8):605-25. Review. English, Italian.
Davie SN, Grocott HP Impact of extracranial contamination on regional cerebral oxygen saturation: a comparison of three cerebral oximetry technologies. Anesthesiology. 2012 Apr;116(4):834-40. doi: 10.1097/ALN.0b013e31824c00d7.
Green DW A retrospective study of changes in cerebral oxygenation using a cerebral oximeter in older patients undergoing prolonged major abdominal surgery. Eur J Anaesthesiol. 2007 Mar;24(3):230-4.
Hoppenstein D, Zohar E, Ramaty E, Shabat S, Fredman B The effects of general vs spinal anesthesia on frontal cerebral oxygen saturation in geriatric patients undergoing emergency surgical fixation of the neck of femur. J Clin Anesth. 2005 Sep;17(6):431-8.
Kwak HJ, Park SK, Lee KC, Lee DC, Kim JY High positive end-expiratory pressure preserves cerebral oxygen saturation during laparoscopic cholecystectomy under propofol anesthesia. Surg Endosc. 2013 Feb;27(2):415-20. doi: 10.1007/s00464-012-2447-5.
Lee A, Kim SH, Hong JY, Hwang JH Effect of anesthetic methods on cerebral oxygen saturation in elderly surgical patients: prospective, randomized, observational study. World J Surg. 2012 Oct;36(10):2328-34. doi: 10.1007/s00268-012-1676-z.
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.