UCONN Emergency Medicine Interest Group

Posts Tagged ‘OB/GYN’

Venous Thromboembolism in Pregnancy

In BRIEFING on August 14, 2011 at 3:20 PM

Overview
Venous thromboembolism is a life threatening condition that has the unfortunate combination of both increased occurrence and increased difficulty of diagnosis in pregnancy. It is the leading cause of maternal mortality in the developed world (20%), greater than both maternal hemorrhage and pregnancy associated hypertension. As such it is very important to have a high index of suspicion in any pregnant patient seen in the emergency department in distress.

Risk Factors in Pregnancy:
Every pregnant woman is at increased risk of venous thromboembolus due to normal pregnancy changes influencing Virchow’s triad of stasis, hypercoagulability, and endothelial damage.

Stasis

  • Reduction in venous flow velocity in the legs by 50% by 25-29 weeks
  • IVC compression by gravid uterus
  • Compression of left iliac vein by right iliac artery (70-90% of DVTs found in left leg in the pregnant population!)

Hypercoagulability

  • Fibrin generation ↑, fibrinolytic activity ↓, Coagulation factors II, VII, VIII and X ↑, free protein S ↓, resistance to Protein C.

Endothelial damage

  • Delivery associated with vascular injury and changes at uteroplacental surface.
Signs and Symptoms
Unfortunately, many of the classic signs and symptoms of pulmonary embolism and deep vein thrombosis are very similar to the symptoms of normal pregnancy.  Lower extremity swelling, pain in lower abdomen, tachycardia, tachypnea, and dyspnea can all be found in both normal pregnancy and venous thromboembolus.
So when should we work patients up? 

Predictive Scoring Systems
Unfortunately the Well’s criteria has not been validated in pregnancy and is often unhelpful.
A small pilot study (n=194 pregnant women with 17 documented DVTs) described  the LEFt criteria. (Chan et al. Ann Internal Med 2009)
The LEFt Criteria assigns one point to each of the three following criteria:
  • L: Symptoms in the left leg
  • E: Calf circumference difference ≥ 2 cm
  • Ft: First trimester Presentation
This study demonstrated that risk could be stratified based on number of positive criteria. In the group with 0 points, there were no documented DVTs. In the group with one or more points, there were 16% with documented DVT, and in the group with 2 or 3 points there were 58% documented DVT.
While these results are from a small study, it may be helpful in increasing level of suspicion for further workup.

Please click below to see the rest of this post.

Journal Article Synopsis: β-hCG, Ultrasound, and Ectopic Pregnancies

In JOURNAL CLUB on August 8, 2011 at 3:32 PM

Summary of “Use of a β-hCG Discriminatory Zone With Bedside Pelvic Ultrasonography” By Ralph Wang et al, Annals of Emergency Medicine vol 58: pp. 12-20. 2011.

What is already known on this topic:
Currently, pregnant women presenting to the ED with abdominal pain, vaginal bleeding, or syncope are assessed with pelvic ultrasonography and quantitative serum β-human chorionic gonadotropin (β-hCG) to rule out the possibility of an ectopic pregnancy. In 10-30% of these cases pelvic ultrasound is unable to reveal either an intrauterine (IUP) or ectopic pregnancy- an “indeterminate result”. A level of β-hCG above the “discriminatory zone” of 1500-3000 mIU/mL, in combination with an indeterminate ultrasound, has been shown to be associated with ectopic pregnancy.

What question this study addressed:
What is the utility of the β-hCG discriminatory zone in differentiating between ectopic and intrauterine pregnancies after an indeterminate bedside pelvic ultrasonography in symptomatic pregnant patients presenting to the ED?

What was the study design:
Cross-sectional study of 256 first-trimester pregnant patients presenting to ED with symptoms of abdominal pain or vaginal bleeding. All pelvic ultrasonography was performed by emergency physicians who were blinded to the patient’s β-hCG levels. Research assistants (blinded to the ultrasound results) contacted and performed a standardized interview with all enrolled patients at 8 weeks.

What this study adds to our knowledge:
A β-hCG cutoff of 3000 mIU/mL is not acceptable for use in clinical practice when attempting to identify ectopic pregnancy in symptomatic patients with an indeterminate result on bedside pelvic ultrasonography (sensitivity of 35% and specificity of 58%). On follow up, it was found that 65% of patients with an ectopic pregnancy have a β-hCG < 3000 mIU/mL.

How this is relevant to clinical practice:
When pelvic ultrasound is indeterminate for intrauterine pregnancy, serum β-hCG level alone does not differentiate intrauterine and ectopic pregnancy. A β-hCG cutoff of 3,000 mIU/mL will not aid with the exclusion of ectopic pregnancy and will cause 65% of cases to be missed.

Other considerations:
In the future the discriminatory zone of β-hCG must be re-evaluated. The bedside pelvic ultrasound can reliably exclude ectopic pregnancy only when they demonstrate a clear intrauterine pregnancy in symptomatic pregnant ED patients. Practitioners should avoid an inappropriate interpretation of β-hCG levels in patients without a clear diagnostic result.

Ultrasound Case #3

In RADIOLOGY on June 16, 2011 at 8:43 AM

Syndicated from the UCONN EM Residency website; credit to Dr. Russell and Dr. Kleinberg for cases and images.

CC: RLQ abdominal pain.

HPI: 25 yo female presents to ED with severe right lower quadrant abdominal pain beginning yesterday.  LMP about 7 weeks ago.  Denies vaginal discharge or bleeding.  No history of abnormal pap smears, STI’s or previous pregnancies.  Sexually active without protection.

FH: denies alcohol, smoking or drug use.

PE: Afebrile. VSS.  Abdomen tender to palpation suprapubic, right and left lower quadrants.  Pelvic exam with bilateral adnexal tenderness.  Cervical os closed.

Labs: Urinalysis negative for infection.  Urine pregnancy positive. H/H stable.  Quantitative B-hCG: 83,000.

Bedside U/S: (see beginning of post for 1st still image): click for video.

What is the next step in management? (click below to see answer below the fold)

Read the rest of this entry »

Off Service #1: OB/GYN

In OFF SERVICE on April 18, 2011 at 8:02 PM

This is the first entry in what will be a recurring series. Seasoned attendings from specialties outside EM will be asked the following question: “What clinical advice would you give students going into Emergency Medicine regarding an acute issue in your field?”

Dr. Larhmann, OB/GYN, Hartford Hospital:

1. Order type and Rh on pregnant women that come into the ED with a complaint of bleeding, and give Rhogam if appropriate. Rhogam needs to be given within 72 hours to be effective.

2. Consider the diagnosis of preeclampsia if a pregnant woman comes in with headache and visual changes- order a UA and LFTs!

3. Don’t rely on serum B-hCG level for figuring out gestational age; remember that it has a bell-shaped curve.

%d bloggers like this: