November 2016 New in EM

Clinical Question to be answered

• How does a novel bespoke ED risk score for patients with suspected cardiac chest pain (EDACS) compare with TIMI in everyday practice?

Title of paper

• Effectiveness of EDACS Versus ADAPT Accelerated Diagnostic Pathways for Chest Pain: A Pragmatic Randomized Controlled Trial Embedded Within Practice

Journal and year

• Annals of Emergency Medicine 2016

Lead Author

• Martin Than

Name of contributor

• Edd Carlton

Patients studied

• 560 adult ED patients with possible cardiac symptoms suggestive of acute myocardial infarction for which the attending clinician(s) intended to perform serial troponin analysis to investigate for possible acute myocardial infarction.

Intervention (if therapeutic)

• EDACS accelerated diagnostic pathway for identification of low risk patients (0/2hr testing)

Comparison

• ADAPT accelerated diagnostic pathway (0/2 hr testing with TIMI score)

Primary outcome

• Successful discharge within 6 hours of attendance with no Major Adverse Cardiac Events at 30 days

Summary of results

• No difference in proportion of patients successfully discharged between intervention and control arms (EDACS-ADP arm 90 [32.3%] versus ADAPT-ADP arm 96 [34.4%]; difference -2.1% [-10.3% to 6.0%], P=0.65). EDACS identified a greater proportion of patients as low risk but this did not translate to improved clinical effectiveness

Strengths

• Diagnostic RCT (a rare thing) and pragmatic. Compares risk model developed in high risk patients (TIMI) versus a model developed in low risk patients (EDACS).

Weaknesses

• Single centre. Both pathways reliant on 0/2hr sampling rather than a single test. Sex-specific cut-offs used. Contamination and clinician behaviour (ie not following pathway) a significant issue.

Clinical Bottom Line

• Both EDACS and TIMI, in combination with 0/2hr high sensitivity troponin testing will improve ED efficiency

Clinical Question to be answered

• Does the HEART pathway aid discharge decisions?

Title of paper

The HEART Pathway Randomized Trial. Identifying Emergency Department Patients With Acute Chest Pain for Early Discharge

Journal and year

• Circulation Cardiovascular Outcomes, 2015 (we all read that right…)

Lead Author

• Simon Mahler

Name of contributor

• Barbara Backus (if you haven’t caught on already, Barbara created the HEART score…)

Patients studied

• The usual for this type of study – if you had symptoms that someone thought could be ACS and needed ECG and troponin. Excluded STEMI pts.

Intervention (if therapeutic)

• The HEART pathway – Calculate their HEART score and a zero and 3 hour old school troponin. If low risk heart score and normal trops then it advises discharge with no follow up. Ultimate decision was down to the physician.

Comparison

• “Usual care” which is recommended along AHA guidelines but is down to the physician ultimately. The usual practice in USA is often admission for further provocative testing.

Primary outcome

• cardiac testing within 30 days

Summary of results

• 70% in the usual care and 57% in the heart pathway got objective tetsing (this was stat significant and their primary outcome)
• 40% discharge v 18% in the usual care
• No MACE for anyone on follow up
• 4% lost to follow up (10 pts) likely all fine but can’t prove it and of course this would radiaclly change things if they all died of MI
• note average age was 55 in this study.

Strengths

• RCT of a diagnostic pathway – brilliant
• pragmatic – ie allowed the physicians to make the final decision – this is reflective of real life practice

Weaknesses

• Single centre
• non blinded (obviously)
• Primary outcome of cardiac testing is maybe not the most patient orientated outcome.

Clinical Bottom Line

• The HEART pathway reduces testing and improves discharge in this single centre American trial

Clinical Question to be answered

• Does routine anticoagulation reduce important VTE in lower limb fractures?

Title of paper

A Double-Blind, Randomized Controlled Trial of the Prevention of Clinically Important Venous Thromboembolism After Isolated Lower Leg Fractures

Journal and year

• Journal of orthopedic trauma

Lead Author

• Selby

Name of contributor

• Dan Horner

Patients studied

• surgically managed lower leg fractures (no foot or patella aloowed), also excluded pre specificed major trauma patients

Intervention (if therapeutic)

• Prophylactic dalteparin

Comparison

• Placebo injections

Primary outcome

• “Clinically Important VTE”
  • prox DVT on a routine 14 day leg scan
  • VTE in follow up over 90 days(mainly chart review)

Summary of results

• 250 pts recruited but stopped early as an interim analysis found a very low incidence of VTE in both groups and felt it would be futile to continue

Strengths

• Lots of good things, randomised, placebo, important question.
• Reasonable power calculation
• Clinically important VTE sounds good

Weaknesses

• Not immediately relevant to the ED
• They excluded almost all patients with RF for VTE. It’s therefore not surprising that they found a very low rate of VTE in their study when their only risk factor was the surgery.
• Stopped early so it throws off the significance of any potential findings

Clinical Bottom Line

• In this study of post op patients they found a very low rate of VTE and it is possible that very low risk patients do not need prophylaxis. This says little about patients with other risk factors for VTE or patients being discharged from the ED with lower limb casts.

Any other FOAM sites where you found it or who have discussed it already so that we can be sure to give kudos

• Dan has of course done his own work on this with the GEM NET guidelines
• This is the observational trial referred to in this section.

Clinical Question to be answered

Should we cool patients during cardiac arrest?<

Title of paper

induction of therapeutic hypothermia During Out-of-hospital cardiac arrest Using a rapid infusion of cold saline the RINSE trial (rapid infusion of cold normal saline)

Journal and year

• Circulation 2016

Lead Author

• Steve Bernard

Name of contributor

• Simon Carley

Patients studied

• Multi centre, pre hospital study of patients undergoing CPR

Intervention (if therapeutic)

• Up to 2L of 3 degrees saline

Comparison

• Usual care

Primary outcome

• Survival to hospital discharge

Summary of results

• Powered for 2500 pts but stopped early because the TTM trial came out and everyone changed their protocols
• Ultimately had 1200 pts analysed
• No difference in outcomes. There were some “trends” but we’ll stay away from them…

Strengths

• Big numbers, important question, good methods overall

Weaknesses

• As always you could question the choice of primary outcome – surely neuro outcome more important
• Stopped early which always raises the problem of a possible false negative
• They only acheived a small difference in temperature (34.7 in the cold group and 35.4 in the control)

Clinical Bottom Line

• Cooling patients during arrest does not seem to be beneficial