Blood or plasma fentanyl concentrations are expected to be in a range of 0.3–3.0 μg/L in persons using the medication therapeutically, 1–10 μg/L in intoxicated people, and 3–300 μg/L in victims of acute overdosage. Paper spray-mass spectrometry (PS-MS) may be useful for initial testing of samples. History
Fentanyl was first synthesized in Belgium by Paul Janssen under the label of his relatively newly formed Janssen Pharmaceutica in 1959. It was developed by screening chemicals similar to pethidine (meperidine) for opioid activity. The widespread use of fentanyl triggered the production of fentanyl citrate (the salt formed by combining fentanyl and citric acid in a 1:1 stoichiometric ratio). Fentanyl citrate entered medical use as a general anaesthetic in 1968, manufactured by McNeil Laboratories under the trade name Sublimaze.In the mid-1990s, Janssen Pharmaceutica developed and introduced into clinical trials the Duragesic patch, which is a formulation of an inert alcohol gel infused with select fentanyl doses, which are worn to provide constant administration of the opioid over a period of 48 to 72 hours. After a set of successful clinical trials, Duragesic fentanyl patches were introduced into medical practice. Following the patch, a flavored lollipop of fentanyl citrate mixed with inert fillers was introduced in 1998 under the brand name of Actiq, becoming the first quick-acting formation of fentanyl for use with chronic breakthrough pain.In 2009, the US Food and Drug Administration approved Onsolis (fentanyl buccal soluble film), a fentanyl drug in a new dosage form for cancer pain management in opioid-tolerant subjects.
Management
After initial diagnosis of oligohydramnios has been made, the next step is to perform a thorough history and physical exam, followed by diagnostic testing if indicated. Retaking a maternal and family history and performing a physical exam can point to maternal conditions or medications that might be causing the oligohydramnios. Premature prelabor rupture of membranes or prelabor rupture of membranes is ruled out with a nitrizine test, evidence of ferning, or evidence pooling of liquid in the cervix. Sonographic evaluation of the fetus is done to identify fetal anomalies, aneuploidy, fetal growth restriction, or placental abnormalities. The National Institute of Health recommends detailed documentation of certain fetal organs that are most likely to be involved such as the kidneys, bladder, and the umbilical cord. If the lack of amniotic fluid prevents accurate visualization on ultraosund, MRI imaging can be considered. Genetic testing can be useful if fetal anomalies are documented on imaging. An elevated maternal serum alpha fetal protein (MSAFP) can indicate leaking amniotic fluid due to damage to fetal membranes or the placenta. This is associated with a poor prognosis. A maternal blood test or amniotic fluid test can be performed if suspicion of a TORCH infection is high. Increasing amniotic fluid
There is no way to permanently increase the volume of amniotic fluid, but it can be temporarily increased to allow for a complete anatomy scan of the fetus on ultrasound.One way to achieve this is through an amnioinfusion, which is the insertion of 200mL of saline into the amniotic sac.