December 2004

Contributed by readers • Edited by Donald B. Middleton, MD
 

MULTITASKING TEST

Asterixis, also known as the "liver flap," is more than just a bedside assessment of hepatic encephalopathy. It tests for any type of encephalopathy due to a metabolic cause, including renal failure, drug toxicity, and—probably the most useful—elevated pCO₂. To remember the causes of asterixis, Dr. Brady Pregerson in Los Angeles, California, uses an ABCD mnemonic: A for ammonia; B for BUN (renal failure); C for pCO₂, CVA, CNS infection (malaria, encephalitis), or CNS tumor; and D for drugs (aspirin, antidiabetics, seizure medications, and psychiatric medications).
 

THE TOPIC OF TOPICAL ANESTHESIA

Everyone wants local anesthetics to work without injecting; in my experience, topical products often fall short. In Overland Park, Kansas, Dr. Dan Harpt claims that dripping several drops of an anesthetic into a wound and waiting a few minutes will provide some decent anesthesia. That effect combined with slow injection during wound infiltration largely eliminates pain, he says. I believe that gauze soaked with anesthetic is even better, especially if left in place for 10 to 15 minutes. Others favor LAC or TAC (lidocaine or tetracaine with adrenalin and cocaine) or lidocaine gels. Trial and error may help you find your favorite.
 

SCOPE TO THE RESCUE

A foreign body sensation after eating fish is not uncommon. It may be due to a bone that has scratched the throat or has become trapped behind the tonsil or near the larynx. (The husk of a piece of popcorn can do the same thing.) After trying several methods to examine the throat in such situations, Dr. Tomer Begaz of Chicago reports that the technique of Dr. Joseph Milton works best. First spray the throat with topical anesthetic, but be frugal—too much can induce methemoglobinemia, although that is a rare effect. With the patient supine, gently insert a direct laryngoscope as if to intubate. The foreign body is often easily seen for removal.
 

GOOD POINT

To do sharp (pin) discrimination testing without using a pin, which can draw blood and is hard to find sterilized, Lawrence Adler, MD, from Beverly Hills, California, just breaks a cotton applicator in half and uses the point at the break. It is quick, convenient, and sharp enough to elicit the pin sensation without drawing blood.
 

MASK THE PROBLEM

Instead of the paper bag treatment for hyperventilation, Mr. William Fisher, MT-P, PA-S of Forest Grove, Oregon, recommends setting up the patient with a standard oxygen mask or appropriately sized nonrebreather mask so that the patient rebreathes carbon dioxide. As a safety precaution, Mr. Fisher monitors the patient's blood oxygen saturation and if it drops below 91%, he simply turns on the oxygen. He reports that this method, by avoiding the patient anxiety sometimes associated with the "brown bag" technique, tends to produce a quicker resolution of the hyperventilation problem.
 

BREATHLESS

To avoid hyperventilation effects during auscultation, Dr. John Wipfler in Peoria, Illinois, auscultates the back first, followed by the cardiac exam, and then the anterior lung exam. The brief pause in deep breathing during the cardiac exam prevents his patients from becoming dizzy, lightheaded, and perhaps fainting.
 

RUBBER SOLE

From Grand Rapids, Michigan, Dr. Richard Crissman warns that a patient with a puncture wound through a rubber sole may have a piece of rubber embedded in the wound. If the rubber fragment is not removed, infection could follow. Having never encountered this problem, I wonder how often it really occurs and how often the wound needs to be deeply explored. Any advice from readers?
 

MEASURE OF A MAN

What to do to assure accurate measurement when a ruler isn't always handy? In New York City, Dr. Marc Felberbaum eliminated the problem once and for all by photocopying a ruler, cutting it to the appropriate length, and taping it to the back of his ID badge.
 

HAND-OFF COMPLETE

At the change of shift in his Portland, Oregon, emergency department, Dr. Stephen Acosta gives his reliever a four-point summary on a card for each waiting patient. The card lists the two most likely diagnoses, pending labs or procedures, pending consultations, and disposition if not admitted.