Bradbury CL, Singh SI, Badder SR, Wakely LJ, Jones PM Prevention of post-dural puncture headache in parturients: a systematic review and meta-analysis. Acta Anaesthesiol Scand. 2013 Apr;57(4):417-30. doi: 10.1111/aas.12047. Epub 2012 Dec 28. Review.
Gómez-Ríos MÁ, Fernández-Goti MC Pneumocephalus after inadvertent dural puncture during epidural anesthesia. Anesthesiology. 2013 Feb;118(2):444. doi: 10.1097/ALN.0b013e31825e6ecc.
Liang MY, Pagel PS Bilateral interhemispheric subdural hematoma after inadvertent lumbar puncture in a parturient. Can J Anaesth. 2012 Apr;59(4):389-93. doi: 10.1007/s12630-011-9664-6. Epub 2012 Jan 4.
Sachs A, Smiley R Post-dural puncture headache: the worst common complication in obstetric anesthesia. Semin Perinatol. 2014 Oct;38(6):386-94. doi: 10.1053/j.semperi.2014.07.007. Epub 2014 Aug 19. Review.
Shah R, Kubisz-Pudelko A, Reid J Posterior reversible encephalopathy syndrome following an inadvertent dural puncture during an emergency laparotomy for ischemic colitis - a case report. Local Reg Anesth. 2014 Jan 20;7:1-4. doi: 10.2147/LRA.S57660. eCollection 2014.
Stannard D Epidural blood patching for preventing and treating postdural puncture headache. J Perianesth Nurs. 2011 Dec;26(6):411-2. doi: 10.1016/j.jopan.2011.09.002. Review.
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.