EM Clerkship

Introduction

Pulmonary embolism (PE) is caused when a deep venous thrombosis from somewhere else in the body “embolizes” and becomes lodged in the pulmonary arteries

Can cause pulmonary infarction (which mimics pneumonia on chest x-ray)

Basic Approach to the Diagnosis of PE

* Step 1: Consider PE in any patient with signs or symptoms consistent with the disease* Common signs/symptoms* Shortness of breath* Chest pain* Syncope* Tachycardia* Hypoxemia* Hypotension* Step 2: Do not do additional testing for PE in patients with a CLEAR alternative diagnosis* Common alternative diagnoses* COPD exacerbation* Acute coronary syndrome* Pneumonia* Keep in mind that these diagnoses are also the most frequent misdiagnoses in cases of missed PE!!! Be careful.* Step 3: Calculate Wells Score and PERC criteria* Wells score* (I personally use Wells’ Criteria for PE by MDCalc)* Define patient as either “Low” “Medium” or “High” risk* PERC criteria* I use the PERC Rule for PE by MDCalc for this as well* If patient is both low risk wells and meets all PERC criteria…* No additional testing needed!!!* Step 4: Get a D-Dimer* IF… * Low risk Wells but fails PERC criteria* Medium risk Wells score* Step 5: Get a CTA* IF…* Wells score is high* Elevated d-dimer* (Update: it is now established that you can safely use AGE ADJUSTED D-DIMER)* ACEP’s clinical policy supporting this can be found HERE

Final Thoughts

* Bilateral lower extremity ultrasounds not sensitive enough to rule out PE* The classic EKG finding is S1Q3T3

Additional Reading

* Emergency Evaluation of PE: Diagnosis (Journal of Emergency Medicine)* Wells Criteria (MDCalc)* PERC Criteria (MDCalc)* Age Adjusted D-Dimer Policy (ACEP)

There are 3 main “categories” of hemoptysis…

Mild, “Streaky” Hemoptysis

* Most common diagnosis* Bronchitis* Testing plan* Chest xray* Rules out alternative causes of hemoptysis* Pneumonia* Cancer* Pulmonary Embolism* Vasculitis

Scary but Stable Hemoptysis

* Patient is coughing up frank blood* Testing plan* CTA of the chest* CBC* PTT/PT/INR* Electrolytes* Need renal function if giving IV contrast

Oh-My-God-That’s-A-Lot-Of-Blood!!!

* Intubate the patient* Consult cardiothoracic surgery/interventional radiology

Additional Reading

* Hemoptysis: An EM Primer (emDOCs)

Salicylate toxicity is the great toxicologic mimicker!!!

Step 1: When to Suspect Salicylate Overdose

* Signs of CNS stimulation* Tachypnea* Hyperthermia* Altered mental status* Signs of GI irritation* Nausea/Vomiting* Abdominal pain* Common “mimicker”* Sepsis* Acute abdomen

Step 2: Testing Plan

* Electrolyte panel* Anion gap metabolic acidosis* Sodium – Chloride – Bicarb* Normal anion gap (AG) is <10* Caused by salicylic acid and lactic acid* Blood gas* Mixed respiratory ALKALOSIS and metabolic ACIDOSIS

Step 3: Obtain Serum Salicylate Level

Step 4: Treatment Plan

* Mild salicylate toxicity* Alkalinize urine with sodium bicarbonate (NaHCO3) drip* Severe salicylate toxicity* Dialysis

Additional Reading

* Salicylate Poisoning (LITFL)

Acetaminophen is the most important overdose in toxicology

Step 1: Check a Serum Acetaminophen Level

* Common situations where testing is ordered* Suicidal ideation* Severe depression* Overdose

Step 2: Consult the Rumack-Matthew nomogram

* Only works for acute/single ingestions of acetaminophen* Loses reliability if patient is on drugs that affect bowel motility* If the time of ingestion is KNOWN* Measure acetaminophen level 4 hours post-ingestion* Plot on nomogram and treat if above line* If time of ingestion is UNKNOWN* Determine earliest possible time of ingestion* Plot on nomogram and treat if above line

Step 3: Order hepatic labs (LFTs)

* AST* ALT* Alk Phos* PTT/PT/INR

Step 4: Identify Phase of Toxicity

* Phase 1/Day 1* High acetaminophen levels* Normal LFTs* Minimal symptoms* Phase 2/Day 2* Acetaminophen level starts decreasing* LFTs level starts increasing* Mild GI symptoms develop* Abdominal pain* Nausea/vomiting* Phase 3/Day 3* Acetaminophen levels are normalized* LFTs are peaking* Phase 4* Recovery

Step 5: Give N-Acetylcysteine (NAC)

* If patient meets criteria on Rumack-Matthew nomogram* If patient is in phase 1, 2, or 3

Additional Reading

* Acetaminophen Overdose and NAC Dosing (MDCalc)

T→ Episode Summary

This week we will discuss some Emergency Medicine 101. This is my personal approach to the initial management of crashing patients. Not only does this algorithm work well in real life, it also works well in sim, and during verbal cases with my attendings. Listen to the old ABC episodes if you want to go more in depth.

Common Causes

* Structural* Cancer* Post-menopausal bleeding is cancer until proven otherwise* Fibroids* Adenomyosis* Polyps* Coagulopathy* Present in approximately 20% of non-pregnant vaginal bleeding* Most common = Von Willebrand Disease* Hormonal causes* Dysfunctional uterine bleeding

Basic Approach to Non-Pregnant Vaginal Bleeding

* Step 1: Pelvic exam* The utility of this is debated* It is best to sound thorough on your clerkship* Have a chaperone present and document this (include the chaperones name)* Step 2: Obtain Labs* CBC* Anemia?* Thrombocytopenia?* Coags* aPTT is prolonged in 50% of patients with Von Willebrand Disease!* Thyroid (TSH)* Can be obtained outpatient* Common cause of hormonal related vaginal bleeding* Step 3: Pelvic ultrasound* Evaluates for ANATOMIC causes of vaginal bleeding* Step 4: NSAIDS* This treats both abdominal pain/cramping* Also improves bleeding* Step 5: Oral contraceptive pills* Can be started on an outpatient basis* Useful in patients with hormonal/dysfunctional uterine bleeding* Stabilizes endometrial lining

Additional Reading

* NBME Shelf Review: OBGYN (EM Clerkship)* Non-Pregnant Vaginal Bleeding (WikiEM)

Today we are learning what to do when somebody cuts their fingertip off. Trust me, it’s not as straight-forward as you would think.

The pregnancy test is the most important test in females of reproductive age!

Five Important Tests in 1st Trimester Vaginal Bleeding

* CBC* Hemoglobin/Hematocrit* Mild anemia in pregnancy is physiologic and normal* Thrombocytopenia* Type and Screen* Required for blood transfusion* Determines if patient needs RhoGAM* Rho(D) immune globulin* Binds fetal Rh antigens from a fetus so that mother doesn’t develop antibodies against future Rh positive children* Prevents hemolytic disease of the newborn* Give to Rh negative mothers to protect future Rh positive children* Quantitative hCG* hCG >1500* “Cutoff” where definitive pregnancy should be seen on ultrasound* If no pregnancy is seen, highly concerning for ectopic pregnancy* hCG <1500* Ectopic pregnancy still possible* Common for healthy early pregnancies to not be visualized below this level* Urinalysis (UA)* Treat asymptomatic bacteriuria in pregnant patients* One of the only times UTI should be treated in asymptomatic patients* Theoretical increased risk of miscarriage* Pelvic ultrasound* Evaluates for ectopic pregnancy* Subchorionic hemorrhage* Miscarriage

Additional Reading

* Ectopic Pregnancy (EM Clerkship)

Common Causes of Constipation

* Lifestyle* Low fiber diet* Minimal water intake* Poor exercise* Medications* Especially opiates* Endocrine/electrolytes* Hypothyroidism* Hypercalcemia* Bowel obstruction* Delayed colonoscopy* Unintentional weight loss* Previous abdominal surgeries* Rectal problems* Anal fissures* Fecal impaction* Masses

How to Treat Constipation

* Fiber (ex. Metamucil, Citrucel)* Adds structure to the stool* Water (polyethylene glycol/miralax)* Hydrates the stool* Fat (colace)* Softens the stool* Stimulants (Senna)* Increases intestinal activity* Decreases transit time* Suppositories (Glycerine, Dulcolax, Fleet)* Stimulate rectum and cause reflexive bowel movements

Additional Reading

* Constipation Treatment and Management (Medscape)