Preeclampsia

Hi everyone, Our Thursday POTD inspiration comes from a case mentioned to us today by Dr. Kay Odashima. We're talking preeclampsia! This is a can't-miss diagnosis in our pregnant and postpartum patients, so let's review.

Interesting fact: "eclampsia" has its roots in the Ancient Greek eklámpō, meaning to “burst forth violently” 😱

Preeclampsia is seen in women >20 weeks gestation or up to 4 weeks postpartum, and is subdivided into mild or severe, based on the absence/presence of end-organ dysfunction:

Mild:

• BP >140/90
• 2+ on urine dipstick
• Well appearing, mild leg swelling, otherwise asymptomatic, normal bloodwork

Severe:

The diagnostic workup is similar to that done for hypertensive emergency: CBC, BMP, LFTs, coags (if the patient looks sick, to screen for DIC), uric acid, UA / urine dip looking for proteinuria.

Preeclampsia is associated with significant risk for morbidity and mortality, including:

• DIC
• Pulmonary edema
• Intracranial hemorrhage
• PRES (Posterior Reversible Encephalopathy Syndrome, dx on MRI brain)
• Placental abruption (in a preeclamptic with vaginal bleeding, assume abruption until proven otherwise!)
• HELLP syndrome
• Progression to eclamptic seizuresSafe antihypertensive drugs for treatment: Goal BP: <160/110. Maximize one agent before moving on to a second agent. 

In addition, IV magnesium should be given to any preeclamptic with severe features: dosed at 4 grams IV load (over 5-10 minutes) followed by infusion at 1-2 gram/hr for 24 hr.

Disposition: ALWAYS consult with OB/GYN in any patient with preeclampsia. Even if these mild patients qualify for discharge home, they need extremely close OB follow-up. Patients with severe features need to be admitted to the OB floor and monitored until delivery (ideally at/after 34 weeks if possible). Remember, delivery is the definitive treatment for preeclampsia!

For me, the key takeaways are:

• "High-normal" BP is NOT NORMAL in this population: >140/90 is considered mild preeclampsia!
• Preeclampsia can manifest up to 4 weeks postpartum!
• In a healthy woman presenting with new seizure and no obvious cause, think eclampsia and give mag!

References: http://www.emdocs.net/preeclampsia-and-eclampsia-common-pitfalls-in-diagnosis-and-management/ http://www.acog.org/Resources-And-Publications/Task-Force-and-Work-Group-Reports/Hypertension-in-Pregnancy

Warfarin Wednesday

Hey everyone,

After a somewhat heated (well as heated as us third years can get these days) conversation in small group regarding the epistaxis pt with a supra-therapeutic INR I decided to share some info regarding INR reversal based on the current guidelines.

Things to consider:

• Evidence of active bleeding
• Magnitude of INR
• Indicatino for anticoagulation
• RFs for bleeding
  • Recent bleed w/in 4 wks, surgery w/in 2 weeks, Plt < 50, Liver disease, antiplatelets
• Volume status?

Options:

• Vitamin K PO and IV- Warfarin is a VitK antagonist so makes sense right?
  • Similar affects between PO and IV at 24hrs but IV has onset of 6-8hrs
• FFP- Includes all coagulation factors, has an INR of 1.6
  • VitK dependent factors in concentration of 1U/mL
  • In a 70 kg Patient: 1 Unit Plasma increases most factors ~2.5% 4 Units Plasma increase most factors ~10%
• PCC (Prothrombin complex concentrate) 3 has Factor 2,9, 10, 4 has 7 also... we only have 4 in our ED I believe.

Bleeding Patient:

• ALWAYS STOP THE COUMADIN!!
• INR >1.5 w/ life threatening bleed ( ICH, GI, hemodynamic instability)
  • VitK 5-10mg IV
  • PCC 50IU/kg IV AND FFP 150-300mL
    • If PCC unavailable then 15mL/kg of FFP
• INR >2 w/ clinically significant but not life threatening bleed
  • VitK 5-10mg IV
  • PCC 35-50 IU/kg IV
• Minor bleeding:
  • Low risk? Rpt INR next day
  • High Risk or INR >4.5 PO VitK 1-2mg or IV 0.5-1mg and close followup w/in 24hrs

NOT Bleeding:

• INR <4.5 Omit next dose, resume at lower dose when INR is therapeutic
• 4.5-10: Omit dose
  • If High risk bleed consider PO VitK 1-2mg or IV 0.5-1mg and pt needs close followup within 24hrs
• >10: Stop warfarin, VitK, repeat INR at 12-24 hrs
  • High risk patient? Consider PCC 15-30IU/kg

A somewhat simplified algorithm:

A nice concise chart brought to you by our colleagues in Wales:

https://www.aci.health.nsw.gov.au/__data/assets/pdf_file/0010/319735/warfarin-reversal-guidelines-may-2016.pdf

Sources: Circulation, Surgical Critical Care guidelines, LITFL, CHEST

Trauma Tuesday: approach to C-spine imaging

For this week's edition of Trauma Tuesday, let's talk about our systematic approach to C-spine imaging in trauma patients, specifically focusing on if/when an MRI is warranted. We all know the initial workup -- Patient arrives in a cervical collar after an MVA. Depending on our level of suspicion for serious c-spine injury based on mechanism and exam, and perhaps depending also on whether the trauma team was called, there are a few ways to proceed: 1) Really low suspicion (minor fender bender, pt was able to ambulate out of the vehicle): apply one of your clinical decision rules (i.e. NEXUS), and if all criteria fit, clear the collar yourself and be done. 2) Moderate suspicion (mechanism still low but pt maaaybe has some midline tenderness on your exam): CT C-spine (has basically replaced x-rays due to superior sensitivity and specificity for detecting C-spine injuries)

Let's say that you proceed with a CT C-spine, and it comes back negative. You go and reassess your patient, who continues to report cervical spine pain upon palpation. What now?

In a large multi-center prospective study published in Dec 2016 by the Western Trauma Association (attached here), the authors concluded that in patients with both a negative CT scan and a normal neurologic exam, the sensitivity was 100% for determining absence of clinically significant C-spine injury.

How did they reach this bold conclusion? Let's backtrack. They included a convenience sample of over 10,000 adult trauma patients who received a CT C-spine after failing NEXUS (breakdown: 45% failed due to distracting injuries, 49% failed due to persistent midline ttp, 5% failed due to abnormal neurologic findings) 90% of these patients ended up with a normal CT C-spine. Of these 90%, a portion ended up getting an MRI C-spine (decision was left up to the treating physician rather than formal protocol). In the end, only 3 patients total were found to have a C-spine injury on MRI when the CT had been negative (in stats-speak, a false negative!) Moreover, all 3 of those patients had an abnormal neurologic exam prompting the decision for MRI, and all 3 were diagnosed with central cord syndrome (classically symptoms worse in upper extremities than lower, often presenting as paresthesias). For CT C-spine imaging alone, this study showed a sensitivity of 98.5% for ruling out clinically significant C-spine injury. Add on the presence of a normal neurological exam, and there were absolutely ZERO patients with significant C-spine injuries who were overlooked with CT C-spine imaging alone.

How's that for evidence? Next time our trauma colleagues might request a knee-jerk MRI C-spine on a patient with iffy "persistent midline tenderness" and a normal CT, we can engage in a respectful and productive discussion about the true utility of such imaging.

TL;DR Take Home Points: Trauma patients who fail NEXUS should get a CT C-spine. CT C-spine alone has excellent sensitivity MRI is indicated in patients with neuro deficits, regardless of negative CT C-spine. Combining your clinical gestalt with evidence-based practice = formula for success.

References: EM:RAP June 2017 https://www.ncbi.nlm.nih.gov/pubmed/27438681