The Berlin definition, proposed in 2012, breaks with tradition by establishing three risk strata that are based on the degree of hypoxemia as assessed at a minimum positive end-expiratory pressure (PEEP).
Benign paroxysmal positional vertigo (BPPV) is characterized by brief spinning sensations, usually lasting less than 1 minute, which are generally induced by a change in head position with respect to gravity.
Guidelines for urinary indices whereby established Acute Renal Failure (ARF) can be distinguished from renal vasoconstriction with intact tubular function (prerenal azotemia).
Acute: Subtle low signal (hypointense) on T1, often difficult to see at this stage, and high signal (hyperintense) on spin density and/or T2-weighted and proton density-weighted images starting 8 h after onset; should follow vascular distribution. Mass effect maximal at 24 h, sometimes starting 2 h after onset, even in the absence of parenchymal signal changes. No parenchymal enhancement with paramagnetic contrast agent. Territorial intravascular paramagnetic contrast enhancement of “slow-flow” arteries in hyperacute infarcts; at 48 h, parenchymal and meningeal enhancement can be expected.
Infarction: focal hypodense area, in cortical, subcortical, or deep gray or white matter, following vascular territory, or watershed distribution. Early subtle findings include obscuration of gray/white matter contrast and effacement of sulci, or “insular ribbon.”
A DNR order may be written any time that two of the following clinical criteria are present and the prognosis has become clear for and shared whenever possible between physician(s), patient, and family (or appropriate surrogate).