Grand Rounds Recap 8/3/16

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Taming the SRU with Dr. Thompson

Case of a minor MVC with preceding stroke symptoms:

Depending on the study you read

  • 1.3% of MVCs are precipitated by medical emergencies (seizures, syncope, diabetic reactions, stroke)
  • 11% of patients in one study had a medical cause of their trauma

Factors that can increase the risk of a medical cause for trauma include

  • Age >85yo, single vehicle accident, h/o CVA, h/o valvular heart disease, h/o DM 

Factors specifically increasing the risk of stroke as a preceding cause of MVC

  • Age >70yo, h/o vascular disease, minor injury MVC, single car MVC

Patients found down +/- AMS can lead to delays in diagnosis, keep a broad differential (syncope, hypoglycemia, arrhythmias, stroke/TIA). 

 

R4 Case F/U with Dr. Axelson - STEMI and Other Musings

Case of a STEMI in a female with aspirin allergy and subclavian stenosis:

ASA/NSAID allergy is second only to antibiotics, with a prevalence of 0.5-7%

Intolerance to NSAIDS includes:

  • NSAID-induced asthma, NSIUA
  • Single NSAID induced urticarial/angioedema or anaphylaxis, SNIUAA

Both of these processes are secondary to the build up of the leukotrienes causing inflammatory symptoms and insensitivity, but are not true IgE mediated anaphylactic reactions.

Case reports do exist of IgE-mediated ASA allergy, however incidence of true anaphylaxis to ASA is unknown. 

Aspirin in STEMI

ASA use in STEMI dates back to 1988 and the ISIS-2 Trial: 

ISIS-2: Randomized STEMI patients to streptokinase, ASA, neither or both: both streptokinase and ASA decreased cardiovascular death by a quarter (From 12% to 9%). Aspirin was as efficacious as lytics in acute STEMI!

Dual anti-platelet therapy

Dual anti platelet therapy with aspirin and plavix decreases the odds of vascular death in ACS by 15% and by 30% in patients undergoing PCI! All cause mortality, however, is not significantly effected.

So if you can't give aspirin, consider dual anti platelet therapy with both P2Y12 load and 2B/3A inhibitor at the same time. 

Subclavian stenosis: 

Patients with aortic arch atherosclerotic disease tend to be older than patients with other vascular disease pattern. This type of vascular disease portends a worse prognosis for all cause mortality than other types of vascular disease (coronary artery disease, lower extremity arterial disease). 

Does the initial troponin in the ED correlate with infarct size?

No: 24, 48, 72, 96 h troponin does correlate with infarct size on cardiac MRI, but admission troponin does not.

Consultant of the Month with Dr. Tim Smith

Cangrelor:

  • IV reversible P2Y12 inhibitor
  • Significant reduction in adverse coronary events without any increased bleeding
  • Onset of effect within 2 minutes of IV bolus
  • Half-life 5 minutes
  • Don't give with clopidogrel or prasugrel (they are blocked and ineffective with cangrelor)
  • Approved, but expensive. Good when PO intake is an issue

Updates in PE

Massive PE: sustained hypotension, inotropic support, pulseless, persistent profound bradycardia

Submassive PE: systemic normotensive, RV dysfunction (+trop, BNP, EKG changes, RV/LV ratio) indicating myocardial necrosis

  • RV/LV ratio greater than 0.9 shown to be independent predictor of mortality
  • Intubate these patients at your peril, as they are preload dependent

The PEITHOS Trial

1005 patients with submassive PE randomized to single dose tenecteplase vs placebo, both groups received standard heparin therapy. 

  • Death and/or hemodynamic compromise were cut from 5.6% in the placebo group to 2.6% in the tenecteplase group (p=0.02). However, this came at an increased risk of extracranial bleeding of 6.3% compared to 1.2% in the placebo group (p=0.0001), as well as a 2.4% risk of hemorrhagic stroke in the tenecteplase group.