Keywords: D-Dimer, Aortic Dissection (PubMed Search)
Can you use a serum d-dimer to rule out aortic dissection?
The answer to the question, in 2010, is no.
There has been a flurry of recent literature about the use of serum d-dimer to rule out aortic dissection. Some studies have shown a sensitivity of nearly 100%, but other studies have shown sensitivities of only 60-70%....pretty abysmal sensitivities. And despite some of the authorities on the subject touting how good the test is, there is not firm literature to support it. Better yet, there are some active medical malpractice cases I am aware of in which the diagnosis of aortic dissection was missed based on a "negative d-dimer."
My suggestion, and the vascular pearl for the day, is to avoid using d-dimer as a aortic dissection rule out strategy until good evidence (if it ever becomes available) exists. I know that people are using this test to rule out the disease, just realize that EVERY time I have ever given a talk on acute aortic disasters, 2-3 people from the audience always share that they had a case of a "d-dimer negative dissection."
Keywords: ischemia (PubMed Search)
Evaluation of the acutely ischemic limb
Some considerations when evaluating/treating patients with acute limb ischemia:
Keywords: bleeding (PubMed Search)
How to stop dialysis fistula/graft bleeding
The number of patients being placed on hemodialysis seems to be increasing. And the ED is where they will go when there is a any complication from their fistula or graft.
Hemodialysis shunts require cannulation with large bore instruments. This combined with heparinization may lead to prolonged bleeding from puncture sites.
What to do when a patient shows up in the ED with persistent bleeding from a fistula puncture site:
Vorwerk D, et al. A simple trick to facilitate bleeding control after percutaneous hemodialysis fistula and graft interventions. Cardiovasc Intervent Radiol 1997.
Keywords: Thrombosis (PubMed Search)
Effort thrombosis, also called Paget von Schrotter disease, occurs when either the axillary and or subclavian veins thrombose. The condition is more common in young, healthy (>males) patients and presents with the usual DVT symptoms of arm pain, swelling, and pain.
The disease was originally described in patients performing vigorous activities, like weight lifting or repetitive over-the-head lifting. This type of activity has been reported to kink the subclavian vein and lead to clot formation.
Diagnosis and therapy is the same for any other type of DVT.
Keywords: Varicocele (PubMed Search)
A varicocele is a collection of venous varicosities in the spermatic veins in the scrotum. This is caused by imcomplete drainage for the pampiniform plexus. This may be seen is up 20% of males and is asymptomatic most of the time. Most are found on the left side.
Why should you care, you might ask? Well, the right spermatic vein drains into the IVC and then into the renal vein, whereas the left spermatic vein drain drains directly into the renal vein.
In the patient with new onset, unilateral varicocele, consider an IVC thrombus/tumor if right sided and a left renal clot if left sided.
A case we had recently was a 30 yo male with nephrotic syndrome (a HUGE risk factor for renal vein thrombosis) who presented with left-sided scrotal swelling. He was found to have a left-sided varicocele. Based on this finding, a renal sono was performed and the diagnosis of left renal vein thrombosis was made.
1. Junnila J, Lassen P. Testicular masses. Am Fam Physician 1998;57:685-92
Got some interesting info today on the costs of some commonly used antihypertensive medications. Keep in mind that in patients with severe hypertension, your options of IV drips are limited.
Here is some info from our hospital:
Fenoldopam - $113.28
Nicardipine - $94.67
Esmolol - $82.15
Nitroprusside - $20.86
Labetalol - $14.40
Nitroglycerin - $2.90
Although Fenoldopam (Corlopam), which has been around for years, is more expensive than Nitroprusside, it is just as effective and without the side effects.
A new drug on the market that we don't have yet, Clevidipine, is just as effective as the big guns Nipride and Fenoldopam. Costs at this point are unknown.
More on antihypertensive medications next week....
Keywords: aortic dissection, syncope (PubMed Search)
Painless thoracic aortic dissection (TAD) and syncope
Patients with TAD do not always present with chest pain. In the International Registry of Aortic Dissection (IRAD) study, 2.2% of TAD cases were painless and approximately 13% of TAD cases presented with isolated syncope (i.e. NO PAIN). Other studies have shown that as many as 15% of TAD cases are painless.
Patients with TAD may present after a syncopal episode. The underlying pathophysiology of syncope is related to proximal rupture into the pericardium with resultant tamponade.
Add TAD to your differential diagnosis of unexplained syncope, especially in older folks and especially if a patient "looks bad" and you don't have a reason.
Keywords: AAA (PubMed Search)
Unusual Presentations of AAA
Many unusual presentations of AAA have been reported in the literature and include:
One more note on the whole urge to deficate thing: any thing that leads to hemoperitoneum may cause this strange complaint (ruptured AAA, ruptured ectopic pregnancy).
Beware of older patients with groin pain!
Lower abdominal pain (mimicking diverticulitis) and isolated groin/hip pain are relatively common presentations of AAA and iliac artery aneurysm and rupture. As many as 15-20% of symptomatic AAAs wil present with hip and/or groin pain.
Bottom line: AAA and iliac artery aneurysm should at the very least be considered in older patients (and in patients with vascular disease) who present with unexplained groin/hip pain.
New Antihypertensive agent coming our way...
Well, we have nitroprusside, labetalol, nicardipine, fenoldopam, etc. Say hello to a new drug that is "reported" to be a great drug for ED patients with severe hypertension (emergencies)....Clevipidine (Cleviprex).
Clevidipine is an ultrashort acting calcium channel blocker that has been found to be a powerful antihypertensive medication.
Unique properties of the drug:
Remains to be seen if this drug will play in a role in the treatment of our severely hypertensive patients....stay tuned...
Keywords: Hypertensive, Encephalopathy (PubMed Search)
Hypertensive encephalopathy (HE) is one of the true hypertensive emergencies. Although usually seen with diastolic BPs greater than 120 mm Hg, it can occur in patients with lower numbers. And the diagnosis can be really tricky to make. Sometimes the diagnosis isn't clear until symptoms resolve from BP reduction .
The presentation is variable and includes:
The goal of treatment is to reduce the BP NO MORE THAN 25% (of the MAP) within the first few hours. In addition, drugs like Hydralazine (which may lead to a precipitous decline in BP) and Clonidine (which can alter mental status) should be avoided.
Medications to consider for treating HE include intravenous drips-Fenoldopam, Nicardipine, Labetalol. Drugs like Nipride are probably best avoided since cyanide toxicity may alter a patient's mental status further.
Keywords: Transvenous pacing (PubMed Search)
We had a very interesting case the other day in the ED. A 60 yo male presented after a syncopal episode. After arriving in the ED he was awake (with a pulse of 50) but then became asystolic, without warning. He then woke up and 10 minutes later became asystolic again. He then woke up again. So, we decided to put in a transvenous pacer.
Some considerations when putting in a transvenous pacer:
Keywords: venous thromboembolism, microalbuminuria (PubMed Search)
Risk of PE/DVT in patients with microalbuminuria....another risk factor to consider??
Microalbuminuria (protein in the urine) is a known risk factor for arterial thromboembolic disease, and recent studies suggest that arterial thromboembolism and venous thromboembolism (VTE) have common risk factors. In a prospective community-based cohort study in the Netherlands, researchers enrolled 8574 adults (age range, 28-75) who were followed for 9 years. People with insulin-dependent diabetes or pregnancy were excluded.
Of 129 identified episodes of VTE, roughly half were deep venous
thromboses, and half were pulmonary embolisms. The annual VTE incidence
rate was 0.12% in patients with normoalbuminuria (<30 mg/24 hours)
versus 0.40% in those with microalbuminuria. After adjustment for known VTE
risk factors and other factors (including hypertension, known coronary arterydisease, and elevated C-reactive protein level), the hazard ratio for
VTE in people who had microalbuminuria, compared with those who had
normoalbuminuria, was 2.0.
Comment: The importance of this study is not in the clinical value of
usingmicroalbuminuria as a marker for VTE risk, because the absolute risk
conferred by microalbuminuria is very low, and the therapeutic
implicationsare unclear. Rather, this study suggests that microalbuminuria is a
marker for endothelial dysfunction in both arterial and venous systems, and it
suggests a mechanism for how statins interact with the endothelium to
prevent VTE (JW Cardiol Mar 29 2009).
So, does this affect us as emergency physician? Unclear. But it may very well mean that we might be dealing with a new risk factor that needs to be taken into consideration when evaluating patients with chest pain or SOB. Obviously, we might need medical records to find this risk factor...can you imagine asking a patient if they have microalbuminuria?
Mahmoodi BK et al. Microalbuminuria and the risk of venous
thromboembolism. JAMA 2009 May 6; 301:1790
Keywords: Nitroprusside (PubMed Search)
Nitroprusside-Friend or Foe?
Nitroprusside is a direct venous and arteriolar vasodilator and is very effective at lowering blood pressure. It has been used for the treatment of hypertensive emergencies for many years and most of are comfortable with using it.
The problems with the drug:
Marik PE, etc. Hypertensive crises: challenges and management. Chest 2007;131:1949-62
Keywords: Hypertensive (PubMed Search)
Follow-up for the Hypertensive Patient
We see hypertensive patients every day, every shift. And, we discharge many of them. So, when do you get them follow-up?
The JNC-7 recommends that patients with BPs > 180/110 mm Hg have follow-up within 7 days. Like most of the HTN recommendations in the primary care setting, this recommendation is based on a "smart person" concensus....and no data.
This is a tremendous issue for us in the ED, because we don't want to see a bad outcome in our discharged hypertensive patients.
Some pearls regarding discharging the very hypertensive (but asymtomatic) patient:
Keywords: Hypertension, End-Organ Damage (PubMed Search)
Evaluation of End Organ Damage in Hypertensive Patients
No evidence to date supports the ED workup for end-organ damage in asymptomatic hypertensive patients.
End-Organ Damage Pearls:
Keywords: AV fistulas, bleeding (PubMed Search)
Bleeding AV Fistulas
It is not an uncommon complaint for dialysis patients to present with bleeding from their fistula. They can lose a large amount of blood in a short period of time if not treated promptly, and if treated too agressive their fistula can clot off. Some tips on how to control the bleeding.
Most of the bleeding occurs at the site that the needle puntured the fistula. If it is due to an ulcer eroding into the fistula these tips may not be effective.
I typically check a CBC and coags. Once the bleeding is controlled observe the patient for awhile [typically the hour to hour and half to get the labs back] and then road test them with a walk around the Emergency Department to ensure it does not start bleeding again.
Keywords: aortic dissection (PubMed Search)
BEWARE sudden onset thoracic back pain
Just reviewed a case last week of a person who presented with back pain (thoracic) as the sole manifestation of an aortic dissection. No chest pain, belly pain, etc. JUST severe, acute, thoracic back pain.
Keys to staying out of trouble:
Keywords: Pulmonary Embolism (PubMed Search)
Pulmonary Embolism-Beware Two Important Atypical Presentations
Seems like we have had several atypical PE presentations recently so I thought it timely to quickly highlight some of the well-reported presentations of pulmonary embolism. Remember, although we won't and can't diagnose every case, these types of presentations should at the very least prompt us to consider the diagnosis.
Atypical PE Presentations:
Thrombolytic Therapy for Pulmonary Embolism
Indications for administration of fibrinolytic therapy for acute PE:
Kline. Carolinas Medical Center.
Stein. Pulmonary Embolism. 2008