When the PERC Rule Fails
Kline et al developed a clinical decision tool based on parameters that could be obtained from a brief initial assessment to reasonably exclude the diagnosis of pulmonary embolism (PE) without the use of D-dimer in order to prevent unnecessary cost and the use of medical resources. 1 Many of us have used the Pulmonary Embolism Rule-out Criteria (PERC) rule by now, but we should be clear on what it includes. Are we using it appropriately?
What’s the first thing that pops into your head when you see an older woman presenting to the ED from a nursing facility with atraumatic altered mental status? If you’re like me, ‘UTI’ comes quickly to mind. I then banish the thought of a UTI and force myself to go through a worst-first differential diagnosis to exclude, either through the history and clinical assessment or through testing, more dangerous causes. This is a case of a 67-year-old woman with an unusual cause of altered mental status… and a UTI.
Intracranial injury is the leading cause of death and disability in children. It can arise after severe, moderate, or minor head injury. Children with minor head injury present the greatest diagnostic dilemma for emergency physicians, as they appear well but a small number will develop intracranial injuries. The question that often arises in the ED is:



