Ultrasound in Ectopic Pregnancy

Brief HPI:

A 27 year-old female is brought in by ambulance with syncope. Pre-hospital providers report that the patient developed pelvic pain, vaginal bleeding and lost consciousness. On their arrival, her blood pressure was 80mmHg systolic, point-of-care glucose was normal – a peripheral IV was started, fluids were administered and the patient was transported to the emergency department. On arrival, vital signs were notable for tachycardia and hypotension. The patient was lethargic, maintaining arousal only with constant verbal or noxious stimulation. Her abdomen was markedly tender throughout with rebound and involuntary guarding. Her last menstrual period was 5 weeks ago and she suspected that she was pregnant. Peripheral venous access was expanded and uncrossmatched blood products were rapidly transfused. Whole blood on a point-of-care pregnancy test was positive1, and a bedside FAST demonstrated free intraperitoneal fluid in the hepatorenal recess with large free pelvic fluid. Gynecology was consulted for emergent operative management of suspected ruptured ectopic pregnancy with hemorrhagic shock and the patient was taken to the operating room.

Algorithm for the Evaluation of Suspected Ectopic Pregnancy

Algorithm for the evaluation of ectopic pregnancy

Gallery

The POCUS Atlas
The ultrasound images and videos used in this post come from The POCUS Atlas, a collaborative collection focusing on rare, exotic and perfectly captured ultrasound images.
The POCUS Atlas

Ruptured Cornual Ectopic

Tubal Ectopic Pregnancy

Tubal Ectopic Pregnancy

Ectopic Pregnancy

Ectopic Pregnancy

Positive FAST in Ruptured Ectopic

Positive FAST in Ruptured Ectopic

The evaluation of suspected ectopic pregnancy, as with all complaints in the emergency department, begins with an assessment of patient stability: airway, breathing and circulation. The unstable patient requires immediate interventions to secure each critical component, all temporizing measures until the patient can be taken to the operating room for definitive management.

The evaluation and management algorithm for stable patients is dependent on findings of transabdominal & transvaginal ultrasonography, quantitative hCG level (relative to the institution-dependent discriminatory zone), and the identification of high risk historical and examination features that would prompt specialist consultation despite otherwise benign diagnostic tests.

If ultrasonography demonstrates a definite ectopic pregnancy (extrauterine live embryo,  adnexal mass containing yolk sac), gynecology consultation is warranted – the table below details candidates for attempts at pharmacologic therapy.

Requirements for methotrexate administration2,3

Absolute
Hemodynamic stability
Ultrasound findings consistent with an ectopic pregnancy
Willingness of the patient to adhere to close follow-up
No existing organ dysfunction: hepatic, renal, pulmonary, hematologic, immune
Relative
Unruptured ectopic mass <3.5cm
No fetal cardiac activity detected
hCG <5000 mIU/L

If an intrauterine pregnancy is identified such as a live embryo or yolk sac, barring the presence of risk factors for heterotopic pregnancy (namely, the use of assisted fertilization methods 2, 4-6), then an alternative cause for the patient’s symptoms should be sought.

If the ultrasound is non-diagnostic, patients should be stratified according to risk based on historical features, examination findings and quantitative hCG. If the hCG is above the institutional discriminatory zone, the absence of a definitive IUP is concerning, elevating suspicion for a non-visualized ectopic and warrants gynecology consultation. If the hCG is below the discriminatory zone, then certain features such as the presence of abdominal, adnexal or cervical motion tenderness, or high-risk ultrasonographic features including greater-than-moderate free pelvic fluid, complex fluid, or complex adnexal masses may be secondary features of ectopic pregnancy – again warranting consultation. If no high-risk features are present, close follow-up with repeat hCG and ultrasonography is reasonable.

Risk factors for ectopic pregnancy3

Risk factor OR
Previous tubal surgery 21
Sterilization 9.3
Previous ectopic 8.3
In utero exposure to diethylstilbestrol 5.6
Current IUD 5.0
History of PID 3.4
Infertility 2.7
Advanced maternal age 1.4-2.9
Smoking 1.5-3.9

Examination Findings in Ectopic Pregnancy6

Finding LR+
Cervical motion tenderness 4.9
Peritoneal irritation 4.2
Adnexal mass 2.4
Adnexal tenderness 1.9

Ultrasound Findings in Ectopic Pregnancy 7

Finding LR+
Ectopic cardiac activity >100
Ectopic gestational sac 23
Ectopic mass and fluid in Pouch of Douglas 9.9
Fluid in Pouch of Douglas 4.4
Ectopic mass 3.6
No IUP 2.2
Normal adnexa 0.55

Algorithm for the Evaluation of Vaginal Bleeding

Algorithm for the evaluation of vaginal bleeding

References:

  1. Fromm C, Likourezos A, Haines L, Khan ANGA, Williams J, Berezow J. Substituting whole blood for urine in a bedside pregnancy test. J Emerg Med. 2012;43(3):478-482. doi:10.1016/j.jemermed.2011.05.028.
  2. Bhatt S, Ghazale H, Dogra VS. Sonographic Evaluation of Ectopic Pregnancy. Radiol Clin North Am. 2007;45(3):549-560. doi:10.1016/j.rcl.2007.04.009.
  3. Barash JH, Buchanan EM, Hillson C. Diagnosis and management of ectopic pregnancy. Am Fam Physician. 2014;90(1):34-40.
  4. Lin EP, Bhatt S, Dogra VS. Diagnostic Clues to Ectopic Pregnancy. Radiographics. 2008;28(6):1661-1671. doi:10.1148/rg.286085506.
  5. Winder S, Reid S, Condous G. Ultrasound diagnosis of ectopic pregnancy. Australas J Ultrasound Med. 2011;14(2):29-33. doi:10.1002/j.2205-0140.2011.tb00192.x.
  6. Crochet JR, Bastian LA, Chireau MV. Does this woman have an ectopic pregnancy?: the rational clinical examination systematic review. JAMA. 2013;309(16):1722-1729. doi:10.1001/jama.2013.3914.
  7. Mol BW, van Der Veen F, Bossuyt PM. Implementation of probabilistic decision rules improves the predictive values of algorithms in the diagnostic management of ectopic pregnancy. Hum Reprod. 1999;14(11):2855-2862.
  8. First-Trimester Emergencies: A Practical Approach To Abdominal Pain And Vaginal Bleeding In Early Pregnancy. October 2003:1-20.
  9. Paspulati RM, Bhatt S, Nour S. Sonographic evaluation of first-trimester bleeding. Radiol Clin North Am. 2004;42(2):297-314. doi:10.1016/j.rcl.2004.01.005.
  10. Anderson FWJ, Hogan JG, Ansbacher R. Sudden Death: Ectopic Pregnancy Mortality. Obstet Gynecol. 2004;103(6):1218-1223. doi:10.1097/01.AOG.0000127595.54974.0c.
  11. Lozeau A-M, Potter B. Diagnosis and management of ectopic pregnancy. Am Fam Physician. 2005;72(9):1707-1714.
  12. Stone MB. Emergency Ultrasound Diagnosis of Ruptured Ectopic Pregnancy. Academic Emergency Medicine. 2009;16(12):1378-1378. doi:10.1111/j.1553-2712.2009.00538.x.
  13. Stein JC, Wang R, Adler N, et al. Emergency Physician Ultrasonography for Evaluating Patients at Risk for Ectopic Pregnancy: A Meta-Analysis. Ann Emerg Med. 2010;56(6):674-683. doi:10.1016/j.annemergmed.2010.06.563.
  14. Fromm C, Likourezos A, Haines L, Khan ANGA, Williams J, Berezow J. Substituting whole blood for urine in a bedside pregnancy test. J Emerg Med. 2012;43(3):478-482. doi:10.1016/j.jemermed.2011.05.028.
  15. Alkatout I, Honemeyer U, Strauss A, et al. Clinical diagnosis and treatment of ectopic pregnancy. Obstet Gynecol Surv. 2013;68(8):571-581. doi:10.1097/OGX.0b013e31829cdbeb.
  16. Arleo EK, DeFilippis EM. Cornual, interstitial, and angular pregnancies: clarifying the terms and a review of the literature. Clinical Imaging. 2014;38(6):763-770. doi:10.1016/j.clinimag.2014.04.002.
  17. Rodgers SK, Chang C, DeBardeleben JT, Horrow MM. Normal and Abnormal US Findings in Early First-Trimester Pregnancy: Review of the Society of Radiologists in Ultrasound 2012 Consensus Panel Recommendations. Radiographics. 2015;35(7):2135-2148. doi:10.1148/rg.2015150092.
  18. Diagnosis and Management of Ectopic Pregnancy: Green-top Guideline No. 21. BJOG. 2016;123(13):e15-e55. doi:10.1111/1471-0528.14189.
  19. Hahn SA, Promes SB, Brown MD, et al. Clinical Policy: Critical Issues in the Initial Evaluation and Management of Patients Presenting to the Emergency Department in Early Pregnancy. Ann Emerg Med. 2017;69(2):241–250.e20. doi:10.1016/j.annemergmed.2016.11.002.
  20. Lee R, Dupuis C, Chen B, Smith A, Kim YH. Diagnosing ectopic pregnancy in the emergency setting. Ultrasonography. 2018;37(1):78-87. doi:10.14366/usg.17044.

Ultrasound in Dyspnea

Brief H&P:

A 68 year-old male with a history of hypertension, diabetes, hyperlipidemia, chronic obstructive pulmonary disease and congestive heart failure (CHF) with depressed ejection fraction presents via ambulance with a chief complaint of shortness of breath. EMS reports that the patient was tachypneic and saturating 80% on ambient air on their arrival. En route, he received nebulized albuterol, nitroglycerin and was started on non-invasive positive pressure ventilation (NI-PPV).

On arrival, he remains uncomfortable-appearing with a respiratory rate of 35 breaths/min and accessory muscle use. His heart rate is 136bpm, blood pressure is 118/85mmHg, and he is saturating 95% on an FiO2 of 100%. Attempts to obtain a history are limited due to difficulty comprehending his responses with the PPV mask on, and prompt desaturation with it off. Lung auscultation is similarly challenging due to ambient and transmitted sounds, although basilar crackles and diffuse expiratory wheezing are appreciated. Cardiovascular examination reveals a rapid and irregularly irregular rhythm. Assessment of jugular venous distension is limited due to the patient’s body habitus and the presence of mask straps around the patient’s neck. Lower extremities demonstrate 2+ pitting edema, symmetric bilaterally. Intravenous access is established and laboratory tests are sent. The ECG technician and portable chest x-ray are called.

The case presentation above demonstrates a common emergency department scenario: a critically-ill patient with undifferentiated dyspnea. Specifically, the scenario reveals a situation where the physical examination is either obfuscated by technical challenges or otherwise indeterminate. The patient is at risk for deterioration and targeted intervention is mandatory. If a COPD exacerbation is assumed, additional nebulized breathing treatments are indicated – a potentially costly jolt of beta agonists if the patient’s atrial fibrillation and rapid ventricular response are the consequence of decompensated systolic heart failure. Take the route of decompensated CHF and prompt afterload reduction with diuresis would be next – if incorrect, not only would the primary cause go untreated, but his tenuously-maintained blood pressure may suffer.

Algorithm for the Use of Ultrasound in the Evaluation of Dyspnea

Algorithm for the Use of Ultrasound in the Evaluation of Dyspnea

1. Lung Ultrasound

An approach incorporating point-of-care ultrasonography may be useful. First, a thoracic ultrasound is performed where certain causative etiologies might be identified immediately – for example absent lung sliding suggesting pneumothorax, or signs of generalized or subpleural consolidation.

The POCUS Atlas
The ultrasound images and videos used in this post come from The POCUS Atlas, a collaborative collection focusing on rare, exotic and perfectly captured ultrasound images.
The POCUS Atlas

Pneumothorax

Hepatization

Shred Sign

Pleural Effusion

2. Cardiac Ultrasound

Other findings on lung ultrasound may point to causes that are not primarily pulmonary. For example, if diffuse B-lines are encountered a focused cardiac ultrasound can be performed to grossly evaluate ejection fraction and estimate right atrial pressure.

B-Lines

Depressed EF

Dilated IVC

3. Venous Ultrasound

Finally, if the lung ultrasound is largely unremarkable (A-lines), a sequence of ultrasonographic findings including right ventricular dilation and the presence of a deep venous thrombosis would point to pulmonary embolism as the diagnosis.

DVT

RV Dilation

All ultrasound graphics from the algorithm are available for free, licensed (along with all content on this site) under Creative Commons Attribution-ShareAlike 4.0 International Public License.

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References

  1. Lichtenstein DA, Mezière GA, Lagoueyte J-F, Biderman P, Goldstein I, Gepner A. A-lines and B-lines: lung ultrasound as a bedside tool for predicting pulmonary artery occlusion pressure in the critically ill. Chest. 2009;136(4):1014-1020. doi:10.1378/chest.09-0001.
  2. Copetti R, Soldati G, Copetti P. Chest sonography: a useful tool to differentiate acute cardiogenic pulmonary edema from acute respiratory distress syndrome. Cardiovasc Ultrasound. 2008;6(1):16. doi:10.1186/1476-7120-6-16.
  3. Gallard E, Redonnet J-P, Bourcier J-E, et al. Diagnostic performance of cardiopulmonary ultrasound performed by the emergency physician in the management of acute dyspnea. Am J Emerg Med. 2015;33(3):352-358. doi:10.1016/j.ajem.2014.12.003.
  4. Lichtenstein DA. Lung ultrasound in the critically ill. Ann Intensive Care. 2014;4(1):1. doi:10.1186/2110-5820-4-1.
  5. Zanobetti M, Scorpiniti M, Gigli C, et al. Point-of-Care Ultrasonography for Evaluation of Acute Dyspnea in the ED. Chest. 2017;151(6):1295-1301. doi:10.1016/j.chest.2017.02.003.
  6. Lichtenstein DA, Mezière GA. Relevance of lung ultrasound in the diagnosis of acute respiratory failure: the BLUE protocol. Chest. 2008;134(1):117-125. doi:10.1378/chest.07-2800.
  7. Images from The POCUS Atlas
  8. Special thanks to Dr. Timothy Jang, Director Emergency Ultrasound Program, Director Emergency Ultrasound Fellowship, Associate Professor of Clinical Emergency Medicine, Department of Emergency Medicine at Harbor-UCLA

Hypotension

Brief H&P:

A 50 year-old male with a history of colonic mucinous adenocarcinoma on chemotherapy presented with a chief complaint of “vomiting”. He was unwilling to provide further history, repeating that he had vomited blood prior to presentation. His initial vital signs were notable for tachycardia. Physical examination showed some dried vomitus, brown in color, at the nares and lips; left upper quadrant abdominal tenderness to palpation; and guaiac-positive stool. Point-of-care hemoglobin was 3g/dL below the most recent measure two months prior. As his evaluation progressed, he developed hypotension and was transfused two units of uncrossmatched blood with adequate blood pressure response – he was started empirically on broad-spectrum antibiotics for an intra-abdominal source. Notable laboratory findings included a normal hemoglobin/hematocrit, acute kidney injury, and elevated anion gap metabolic acidosis presumably attributable to serum lactate of 10.7mmol/L. Computed tomography of the abdomen and pelvis demonstrated pneumoperitoneum with complex ascites concerning for bowel perforation. The patient deteriorated, was intubated, started on vasopressors and admitted to the surgical intensive care unit. The initial operative report noted extensive adhesions and perforated small bowel with feculent peritonitis. He has since undergone multiple further abdominal surgeries and remains critically ill.

Imaging

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CT Abdomen/Pelvis

Free air is seen diffusely in the non-dependent portions of the abdomen: in the anterior abdomen and pelvis, inferior to the diaphragm, and in the perisplenic region. There is complex free fluid in the abdomen.

Algorithm for the Evaluation of Hypotension1

This process for the evaluation of hypotension in the emergency department was developed by Dr. Ravi Morchi. In the case above, a systematic approach to the evaluation of hypotension using ultrasonography and appropriately detailed physical examination may have expedited the patient’s care. The expertly-designed algorithm traverses the cardiovascular system, halting at evaluable checkpoints that may contribute to hypotension.

  1. The process begins with the cardiac conduction system to identify malignant dysrhythmias (bradycardia, or non-sinus tachycardia >170bpm), which, in unstable patients are managed with electricity.
  2. The next step assesses intravascular volume with physical examination or bedside ultrasonography of the inferior vena cava. Decreased right atrial pressure (whether due to hypovolemia, hemorrhage, or a distributive process) is evidenced by a small and collapsible IVC. If hemorrhage is suspected, further ultrasonography with FAST and evaluation of the abdominal aorta may identify intra- or retroperitoneal bleeding.
  3. If a normal or elevated right atrial pressure is identified, evaluate for dissociation between the RAP and left ventricular end-diastolic volume. This is typically caused by a pre- or intra-pulmonary obstructive process such as tension pneumothorax, cardiac tamponade, massive pulmonary embolism, pulmonary hypertension, or elevated intra-thoracic pressures secondary to air-trapping. Thoracic ultrasonography can identify pneumothorax, pericardial effusion, or signs of elevated right ventricular systolic pressures (RV:LV, septal flattening).
  4. Assuming adequate intra-vascular volume is arriving at the left ventricle, rapid echocardiography can be used to provide a gross estimate of cardiac contractility and point to a cardiogenic process. If there is no obvious pump failure, auscultation may reveal murmurs that would suggest systolic output is refluxing to lower-resistance routes (ex. mitral insufficiency, aortic insufficiency, or ventricular septal defect).
  5. Finally, if the heart rate is suitable, volume deficits are not grossly at fault, no obstructive process is suspected, and cardiac contractility is adequate and directed appropriately through the vascular tree, the cause may be distributive. Physical examination may reveal dilated capillary beds and low systemic vascular resistance.

Algorithm for the Evaluation of Hypotension

References

  1. Morchi R. Diagnosis Deconstructed: Solving Hypotension in 30 Seconds. Emergency Medicine News. 2015.

Ultrasound Gallery

Appendicitis

Appendicitis

Non-compressible tubular structure in the RLQ of a patient with focal abdominal tenderness. >6mm in diameter.

Common Bile Duct

Common Bile Duct

A tubular structure typically anterior to the portal vein without flow. Normally measures <4mm, increases by 1mm per decade after 40yrs.

Cellulitis

Cellulitis

"Cobblestone" appearance of soft tissue suggesting infection/edema.

Fetal Heart Rate

Fetal Heart Rate

Placing the M-Mode marker over the most visibly active portion of the fetal heart allows for measurement of the fetal heart rate.

Free Fluid

Free Fluid

Free fluid in the hepatorenal recess.

Hydronephrosis

Hydronephrosis

Severe hydronephrosis.

Thoracic Aorta Aneurysm

Thoracic Aorta Aneurysm

Subxiphoid view of thoracic aorta, markedly dilated (>3cm) with thrombus.

Pericardial Effusion

Pericardial Effusion

Mild pericardial effusion in a patient with pleuritic chest pain.

Inferior Vena Cava

Inferior Vena Cava

IVC without significant respiratory variation.

B-lines

B-lines

B-lines extending deep from pleura suggestive of interstitial fluid accumulation (pulmonary edema).

"Shred" sign

"Shred" sign

Irregular, "shredded" pleural line suggestive of consolidation.

Pneumothorax

Pneumothorax

Transition point with loss of lung sliding in a patient with a small spontaneous pneumothorax.