Upstairs Downstairs

Upstairs Downstairs

Director's Corner

How many clinical shifts does your chair need to work in the trenches in order to stay current with what’s…

Five-Year-Old With Dysuria, Abdominal Pain and Incontinence

Five-Year-Old With Dysuria, Abdominal Pain and Incontinence

Soundings

New patient is a 5-year-old male with a history of recurrent UTIs

Sudden Illness After Dental Procedure

Sudden Illness After Dental Procedure

Visual Dx

A 28-year-old male presents to the emergency department with a chief complaint of chest pain, coughing and shortness of breath.…

Bicep Tendon Rupture

Bicep Tendon Rupture

The Popeye Sign

A 45-year-old-male presents with sudden onset of right arm pain. He reports that he was lifting a heavy piece of…

Leaving Las Vegas... Hopefully

Leaving Las Vegas... Hopefully

By Greg Henry, MD

Travel to medical training venues is becoming more painful. People in line to check-in at hotels want to comment openly…

Understanding ACEP’s Clinical Policy on Seizures

Understanding ACEP’s Clinical Policy on Seizures

ACEP's 2014 Seizure Guidelines

In January, 2014, the American College of Emergency Physicians revised its policy on 'ED Evaluation and Management of Seizures in…

Mid-Level Providers

Mid-Level Providers

Who they are, what they do, and why they’re changing emergency medicine

How to make sense of the puzzle and improve your practice.

When Patients Lie

When Patients Lie

How to Spot Deception, What You Can Do, and Why it Matters

Accusing anyone of lying is serious business, but when that person is your patient, the stakes are even higher. 

Raves and Saves

Raves and Saves

Advanced Emergency Management at Mass Gatherings

EM is crucial at drug-fueled electronic dance festivals, like this month’s Electric Zoo in New York.  

Transfusion Confusion

Transfusion Confusion

Knowing the Real Risks of Blood Transfusion

This routine procedure bears real risks and should be handled accordingly.

The ABCs (and T) of Rural EM

The ABCs (and T) of Rural EM

Situational Awareness is Key

When you’re practicing in the middle of nowhere, planning out a timely patient transfer can be as critical as securing…

DNR Means Do Not Treat . . . and Other End-of-Life Care Myths

DNR Means Do Not Treat . . . and Other End-of-Life Care Myths

Debunking 5 Fallacies

Improve your EOL care and communicate more effectively.

Through the Looking Glass

Through the Looking Glass

Three Novel Use Cases for Google Glass in the ED

How might augmented reality change your practice?

Augmented ED

Augmented ED

The future of emergency medicine?

EPs in Rhode island overcome hurdles to trial Glass for telemedicine and consider other applications.

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    Earlier in the night, you saw a 41 year old with fever, headache, and neck pain.  The labs are back and it does not appear that he has meningitis.  You have just explained this to him, and are walking out of the room, when he complains to you that the LP hurt more than he had expected.  Last year he had an LP for the worst headache of his life and he barely felt a thing.  While initially shocked since you consider yourself one of the “nicer” docs in your group as you use eutectic mixture of local anesthetics (EMLA) prior to performing an LP, you begin to wonder if there is a superior product on the market.

    This meta-analysis included 25 randomized control trials.  The trials compared the efficacy of topical anesthetics to dermal infiltration with local anesthetics and also compared those topical anesthetics to EMLA.  The trials included both men and women who were 3 years old and above.  The authors felt 3 years was the lowest age that children could credibly quantify pain.  All trials had to use some validated pain score such as the visual analogue scale (VAS).  In order to minimize the variability in the meta-analysis, the trials could only involve certain superficial procedures (intravenous cannulation, venipuncture) or deeper instrumentation (arterial cannulation, lumbar puncture).  Studies involving non-intact skin (laceration repair) were not included.  Also all studies involving EMLA had to apply it for at least 45 minutes before the procedure.  The manufacturer suggests one hour, but per the authors, EMLA has been found to work after 45 minutes of application.
   
Ten trials compared EMLA to infiltration with local anesthetic with mixed results.  Five studies involved superficial procedures and five involved deep procedures.  In both subgroups the results were mixed with some trials showing a greater efficacy in EMLA and some showing dermal infiltration to be superior.  Because of significant heterogeneity, the studies involving deep infiltration were not statistically combined.  No study compared EMLA plus local infiltration to either one alone.  The EMLA patch was also compared to EMLA cream in 4 trials.  The analgesic efficacy of each product was found to be the same.  Two of these studies had their results statistically combined but still did not find a statistical difference on the visual analogue pain scale.
   
One study compared lidocaine ointment (xylocaine) to EMLA when used for analgesia in intravenous cannulation.  EMLA was found to be superior; however, it only included 7 patients.  Liposomal lidocaine cream (LMX) was also compared to EMLA in 2 studies.  Both studies found them to have an equivalent amount of analgesia.  In both studies EMLA was applied 60 minutes before the procedure and LMX was applied 30 minutes before the procedure.  Since LMX only had to be applied half as long to work just as well as EMLA, it was concluded to be preferable to EMLA.  When LMX was applied for 60 minutes, the patient did not receive a greater amount of analgesia compared to when it was applied for 30 minutes.  The studies used different pain scales so their results could not be combined.
   
One study compared tetracaine gel to local infiltration in arterial puncture and found comparable efficacy.  Four trials compared tetracaine gel versus EMLA.  In all 4 trials, topical tetracaine was found to provide greater analgesia than EMLA.  However in one of the trials, the difference was not statistically significant. Three trials used the VAS and had their results combined.  Once again a difference favoring tetracaine gel was found to be statistically significant.  However the weighted mean difference of 8.1 mm on the pain scale is less than the 13 mm other studies have found as the minimum decrease in pain that is clinically significant.
   
The last 2 studies compared liposomal encapsulated tetracaine (LET) to EMLA in superficial instrumentation.  Both trials concluded that LET had a greater efficacy even though one trial did not show a statistically significant difference.  When the results of the trials were combined, LET was concluded to be more efficacious.  While the results were statistically significant the difference was still less than the 13 mm found to be clinically significant.
   
While most results were mixed, the authors were able to draw some conclusions.  When EMLA was compared to local infiltration, there was no difference in analgesia.  However since the application of EMLA is painless, whereas local infiltration is painful, EMLA is preferable to local infiltration.  While LMX was not found to have an increase in analgesia compared to EMLA, it did offer two benefits.  First it only had to be applied half as long to work just as well.  Second LMX ($42 for 30 gram tube) is cheaper than EMLA cream ($51 for 30 gram tube). 
 
 

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