ICEM 2014

ICEM 2014

Tintinalli Headlines & Holliman Assumes Presidency

On June 11, EPM Editor-in- Chief and renowned educator Judith Tintinalli took to the stage in Hong Kong to address…

The Medical Malpractice Rundown: A State-by-State Report Card

The Medical Malpractice Rundown: A State-by-State Report Card

When it comes to medical liability laws and culture, where you live matters.

Find out how your state stacks up against the other 49.

CT – Lowering Cost and Radiation

CT – Lowering Cost and Radiation

Medicare pays only about 20% of typical charges and radiation can be reduced by 90%.

The cost of a CT is actually quite nominal – the charge, however, is an entirely different matter. 

 Aftermath: The Night Shift Season 1 Finale Review

Aftermath: The Night Shift Season 1 Finale Review

At Loose Ends

It’s strange calling this a season finale, because it’s only been an 8-episode summer run, and nearly every episode has…

Doximity’s Next Trick: Connectivity at the Point of Care

Doximity’s Next Trick: Connectivity at the Point of Care

You’ve raised $81 million in investments and your physician membership now exceeds that of the AMA. What’s next?

If you're Doximity, it's time to dream big. 

Subcutaneous Insulin in DKA: Safe — But Not Better

Subcutaneous Insulin in DKA: Safe — But Not Better

Newer Isn't Always Better

Studies show that the benefits of subcutaneous insulin over old fashioned IV insulin are marginal at best.

A Return to (Lousy) Form: Episode 7 of The Night Shift

A Return to (Lousy) Form: Episode 7 of The Night Shift

Forks! Strippers! Guns!

Once again, our characters are responding to the (frankly unbelievable) events unfolding around them, rather than driving the action.

Oxygen is a Drug— Act Accordingly

Oxygen is a Drug— Act Accordingly

Understanding the dangers of indiscriminate oxygenation in the ED setting

As with many things in medicine, dogma seems to overpower the evidence in this arena. 

Oh Henry: A Sucker is Born Every Minute

Oh Henry: A Sucker is Born Every Minute

Pharmaceutical Ads, Government, and the Physician-Patient Relationship

Though it pains me to say it, this is one time where caveat emptor doesn’t apply. 


A Ray of Hope

A Ray of Hope

The Night Shift, episode 6

This was the first episode where it felt like the characters were driving the plot.

The Downside of the Upswing

The Downside of the Upswing

You should have cashed in big-time. 
But did you?

The last several years of returns have been among the best ever.

5 Things Your Patients Might Think After Watching ‘Code Black’

5 Things Your Patients Might Think After Watching ‘Code Black’

An inside view of the ED

Code Black provides a harrowing and enlightening window into the front lines of healthcare. 

Talking Points

Talking Points

Link your vision to action

As an ED leader, you must not only have a vision and plan, but you must communicate that vision effectively…

Toxic Liquid Nicotine

Toxic Liquid Nicotine

New FDA regulations proposed for E-cigs

Highly unregulated, the sale of toxic nicotine concoctions for e-cigarette refills pose a serious threat to children.

All Choked Up

All Choked Up

Best Practices for Battery Ingestion

A two-year-old presents at a clinic with persistent cough and neck discomfort and winds up in the ED.

Gag Order

Gag Order

New ruling prohibits would-be ACEP leaders from answering questions from non-ACEP publications.

Greg Henry seldom fails to deliver on a promise. But this time, it looks like it’s out of his control.

Lock the Gates!

Lock the Gates!

Board certification is vital in EM

Last month, Rick Bukata suggested that ACEP open its gates to non-boarded EPs. 
This would be an insult to EM…

AMA Meeting Highlights

AMA Meeting Highlights

Association Gives Nod to First EP President-elect

This June’s AMA Annual Meeting proved as eventful as ever, with one exciting twist that has the potential to impact…

The Storm Episode!

The Storm Episode!

Episode 5 of NBC's "The Night Shift"

It’s time for the passion that’s been building up between the two lead ED doctors for … the past few…

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Sinert and Spektor analyze a systematic review published by McGee and coworkers evaluating the utility of the physical exam in determining if a patient is hypovolemic. McGee and co-workers reviewed studies from 1966 to 1997 which assessed the operating characteristics of physical exam findings in hypovolemia. Two types of studies were included in the review: studies of healthy volunteers who lost a standardized amount of blood via phlebotomy and patients presenting to the emergency department with suspected non-traumatic hypovolemia.

Studies showed postural vital signs may be abnormal in a significant portion of normovolemic subjects. Postural hypotension, defined as a greater than a 20 mm Hg decrease in systolic blood pressure, was seen in 10% of normovolemic subjects less than 65 years of age and between 11–30%of subjects older than 65. The studies of phlebotomized healthy volunteers showed that postural vital signs are highly specific but insensitive (Table 1). In patients with moderate blood loss (450 to 630 ml) no vital sign measurement achieved a sensitivity greater than 27%. In patients with large blood loss (630 to 1150 ml) no measurement exceeded a sensitivity of 33% with the exception of the presence of severe dizziness or increase in heart rate of more than 30 beats per minute, which had a sensitivity of 97%. Delayed capillary refill was highly specific (95%) but insensitive (34%).
 
alt 

In patients presenting to the emergency room with suspected hypovolemia from nontraumatic causes no individual physical exam finding appeared to be useful (postural hypotension, pulse increase >30, dry axilla or mucous membranes or tongue, longitudinal furrows on the tongue, sunken eyes, confusion, upper and lower extremity weakness, garbled speech, and prolonged capillary refill). No exam finding yielded a sensitivity greater than 85% (the presence of dry mucous membranes and longitudinal furrows on the tongue had sensitivities of 85%) and the remainder of findings are far less sensitive. Positive likelihood ratios for changes in postural vital signs were only 1.7 for hypotension and 1.5 for pulse increase greater than 30 beats per minute, making these findings unhelpful in diagnosing hypovolemia. It should be noted that these studies used elevated BUN to creatinine ratios, an unproven gold standard. Studies show physical exam findings may be more helpful when used in combination. Elevated BUN to creatinine ratios correlated with an average of four to six physical exam findings, whereas the BUN to creatinine ratio was not elevated when only one finding was present
This LLSA article focuses on the role of likelihood ratios in evaluating diagnostic tests. When used in combination with the pretest probability, the likelihood ratio allows one to arrive at the statistical probability of the presence or absence of disease, the posttest probability.

 A positive likelihood ratio represents the ratio of true positives to false positives provided by a given test. Mathematically speaking, the positive likelihood ratio is represented as sensitivity divided by 1-specificity. For example, if a test provides a true positive 90% of the time and a false positive 10% of the time the positive likelihood ratio would be 0.9/0.1, or 9.0. This means that when a positive result is found it is 9 times more likely to be a true positive than a false positive. A negative likelihood ratio represents the ratio of false negatives to true negatives. For example, if a test provided a false negative test 9% of the time and a true negative 91% of the time, the negative likelihood ratio would be 9:91, approximately 0.1. Thus, a negative result suggests that it is 10 times more likely that disease is absent. A smaller negative likelihood ratio implies that a negative result is more likely to be a true negative. It is generally accepted that a positive test result using a test with a positive likelihood ratio of 10 or greater is almost conclusive of disease and a negative test result using a test with a likelihood ratio of 0.1 or less nearly excludes disease. Likelihood ratios of 1 imply that the test is not useful in ruling in or ruling out disease.

This article suggests that vitals signs, both traditional and postural, are not helpful by themselves in determining if a patient is hypovolemic. Traditional vital signs are insensitive for blood loss. Postural vital signs are similarly unhelpful (i.e. have low likelihood ratios) except in the setting of otherwise healthy individuals with large (greater than 1 liter) blood loss. The reviewers suggest that measurement of serum lactate and base deficit may be a more valuable indicator of hypoperfusion and therefore a better predictor of mortality. While abnormal vital signs are highly specific for hypovolemia, this does not translate well to the emergency room where there are many explanations for tachycardia and hypotension and ruling out emergent conditions is the priority. Instead of vital sign measurements and specific physical exam findings, an organized history, physical exam, and clinical judgment continue to be the best marker for determining volume status.
 
 

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